CN114292307A

CN114292307A - Method for preparing bitter-taste-free mogroside from naturally immature momordica grosvenori

Info

Publication number: CN114292307A
Application number: CN202210020596.6A
Authority: CN
Inventors: 刘庚贵; 黄华学; 曾润清
Original assignee: Jiangxi Haifu Bioengineering Co ltd
Current assignee: Jiangxi Haifu Bioengineering Co ltd
Priority date: 2022-01-10
Filing date: 2022-01-10
Publication date: 2022-04-08
Anticipated expiration: 2042-01-10
Also published as: CN114292307B

Abstract

The invention relates to a method for preparing bitter taste-free momordica grosvenori sweet glycosides by using momordica grosvenori which cannot be naturally matured, which takes old Chinese olive and/or garden balsam fruit as raw materials and comprises the following steps: (1) internal ripening acceleration: selecting old Chinese olive and/or greenhouse-sweeping fruit from fresh collected fructus Siraitiae Grosvenorii, stacking according to size grade, spraying adenosine triphosphate, methionine, jasmonic acid and/or its methyl ester solution in sequence, and standing for ripening; (2) external saccharification; (3) extracting; (4) filtering and clarifying; (5) membrane separation and resin combined refining: cooling the clear liquid of the ceramic membrane, sequentially performing ultrafiltration, performing broad-spectrum macroporous adsorption resin enrichment on the ultrafiltration permeate, decoloring by using ion exchange resin, and desalting and debitterizing by using the adsorption resin; (6) the limited components are as follows: concentrating the desalted and debitterized solution obtained in the step (5), removing pesticide residues and heavy metals, and removing a plasticizer; (7) concentrating; (8) drying to obtain the momordica glycosides without bitter taste.

Description

Method for preparing bitter-taste-free mogroside from naturally immature momordica grosvenori

Technical Field

The invention relates to the field of plant extraction and separation technology and the fructus momordicae industry, in particular to a method for preparing bitter and astringent taste-free momordica glycoside by using naturally immature fructus momordicae.

Background

Momordica grosvenori (Siraitia grosvenorii (Swingle) c. jeffrey), the fruit of perennial vine plants of the cucurbitaceae family, is mainly produced in the township county, the baishou town, the autonomous county of the dragon victory county, the Huanshou county, the Huanyuan province, the Yongzhou province, the shaoyang province and the like.

The fresh momordica grosvenori is collected from the middle of 9 months to the end of 12 months every year, but the fresh momordica grosvenori collected from the middle of 11 months and later has a certain proportion of old Chinese olive fruits and greenhouse-sweeping fruits, and compared with common fruits, the momordica grosvenori cannot naturally mature due to climate and plant nutrition consumption and has bitter taste. The bitter components such as mogrosides II and III are intermediate substances in the formation process of mogroside V, and have not been converted into mogroside V, and the bitter taste cannot be removed by the conventional extraction and separation process, so that the taste and the mouthfeel of the momordica grosvenori product are seriously influenced.

After the momordica grosvenori is harvested, the momordica grosvenori cannot ripen old Chinese olive fruits and green house fruits harvested in 11 middle ten days regardless of being stored at normal temperature or low temperature, and the fresh momordica grosvenori only gradually deteriorates in the storage process. The maturation of Lo Han Guo is a complex process that takes place in the presence of enzymes. The fruit has the formation of ethylene in the natural ripening process, the closer to the fruit ripening, the higher the ethylene content is, once the fruit ripens, the ethylene content is reduced again, and the ethylene generated by the fruit has the effect of promoting the fruit ripening. However, the method for accelerating ripening by adopting exogenous ethylene has no effect or weak effect on the momordica grosvenori, and particularly has no effect of accelerating ripening on old Chinese olive and greenhouse-sweeping fruit harvested in 11 middle-month.

The bitter and astringent taste of mogrosides is due to a number of factors: bitter saponins, i.e., mogrosides II and III and the like, exist in momordica grosvenori which cannot be naturally matured, 2 components generally exist in old Chinese olive and green house sweeping fruit which are collected in autumn and winter after 11 th-middle-ten days, and the content of the momordica grosvenori is higher than that of common momordica grosvenori, and the components are difficult to be effectively removed in the production process and the main component, i.e., mogroside V, by the existing mogroside extraction process, so that the finished product, i.e., the mogroside, has bitter taste in the mouth; the inventor finds that foreign impurities introduced by decolorization of ion exchange resin cannot be completely removed only by technologies such as cation exchange resin desalination or membrane separation desalination and the like in the production process, the taste and the mouthfeel of the mogroside can be greatly influenced, and the product has slightly bitter and astringent taste; the inventor also finds that phenolic acid, pigment and the like existing in fresh grosvenor momordica can also influence the taste and the mouthfeel of the mogroside, and the pure white mogroside has the best taste and mouthfeel, namely the fresh sweet taste of cane sugar on the premise that the product does not contain bitter saponin. Therefore, in the technical process of the production process, the foreign impurities introduced by decoloring the ion exchange resin, and phenolic acid and pigment components existing in the mogroside are removed as much as possible, and the mogroside which has no bitter taste, excellent taste and mouthfeel and sucrose-like fresh sweet taste can be prepared, and the method is also a key technical problem to be solved for further popularization and application of the mogroside.

1, there are known techniques for treating harvested luo han guo to promote ripening:

CN202010872757.5 discloses a processing method of isolated momordica grosvenori and the isolated momordica grosvenori, wherein the processing method comprises the following steps: the immature momordica grosvenori is treated alternately in a first environment with high-intensity red light illumination, high-temperature and high-concentration carbon dioxide and a second environment with low-intensity red light illumination and low temperature. The method provided by the invention can effectively reduce the content of mogroside IIe in the momordica grosvenori, improve the content of mogroside V, promote the maturation of the momordica grosvenori, shorten the maturation and saccharification time of the momordica grosvenori, and is suitable for large-scale industrial application. The method realizes the maturation of the immature momordica grosvenori by only utilizing the condition control of red light illumination, temperature and carbon dioxide, the maturation of the fresh momordica grosvenori is a complex physiological and biochemical process because the fresh momordica grosvenori is picked and separated, the conditions of the synergistic action of relative humidity, oxygen concentration and temperature are not existed only by the adjustment of illumination and temperature, the material basis for promoting the maturation is not existed, and the scientificity of the method is to be demonstrated; carbon dioxide can cause respiratory damage to fresh momordica grosvenori, increase the rate of fruit damage and promote the momordica grosvenori to rot, and the carbon dioxide is a substance with the concentration needing to be controlled and becomes a condition for promoting the momordica grosvenori to mature. Therefore, the effects of the above method are to be further demonstrated.

CN202010874745.6 discloses a method for increasing the content of mogroside substances, which comprises the following steps: (1) sterilizing; (2) breaking shells; (3) treating with a ripener; (4) and (5) adjusting the indoor microenvironment factors. The method breaks through the previous method for promoting the after-ripening of the momordica grosvenori and improving the content of the sweet glycoside substances only by adjusting the external temperature and the illumination conditions, starts from the endogenous mechanism of the after-ripening of the momordica grosvenori, creatively aims at key limiting factors of the after-ripening of the momordica grosvenori, increases exogenous ripening intervention measures, and is matched with the adjustment of external environmental factors, so that the efficient and rapid after-ripening of the momordica grosvenori is realized. Compared with the prior art, the method has the advantages of great improvement range of the content of the sweet glycoside substance, short after-ripening time and capability of eliminating bitter taste. The method comprises the steps of firstly breaking shells of fresh momordica grosvenori and then promoting the maturation of the momordica grosvenori by controlling a ripener and environmental conditions, but has strict time control requirements, and because the fresh momordica grosvenori contains a large amount of glucose, fructose, protein and other substances, the microorganisms and bacteria can be polluted and easily deteriorate in the process of breaking shells and then maturing, the time is not easy to control, and the manual operation difficulty is increased; the maturation of fresh momordica grosvenori is a complex physiological and biochemical process, and the old Chinese olive and the greenhouse fruit collected in 11-month middle ten days are extremely difficult to mature, and cannot mature in a short time even if the shells are broken.

CN201610234523.1 discloses a method for promoting after-ripening of fructus momordicae, belonging to the technical field of fructus momordicae processing. Which comprises the following steps: (1) picking the green siraitia grosvenorii 5: 00-7: 00 in the morning of the green siraitia grosvenorii picking season, lightly taking the green siraitia grosvenorii, putting the green siraitia grosvenorii into a container, timely transporting the green siraitia grosvenorii into a warehouse, taking the picked green siraitia grosvenorii out of the container, and flatly laying the green siraitia grosvenorii on a shelf one by one; (2) adjusting the temperature in the warehouse to be 15-25 ℃, and the illumination condition is that the white light is scattered by 30-60W, the illumination is carried out for 3-18 h every day, the illumination intensity is 800-1580 lx, and the treatment lasts for 6-9 d. The invention can effectively utilize raw materials, shorten the post-treatment time and improve the production efficiency; secondly, the content of mogroside before processing is improved, and a raw material with high content of glycoside V is provided for extracting the mogroside; thirdly, the raw materials are prevented from mildewing in the after-ripening, which is beneficial to ensuring the quality of the dulcoside V extract and has important function and significance for the development of the fructus momordicae industry. The method only adjusts the temperature and the illumination to promote the after-ripening of the momordica grosvenori, and the ripening of the fresh momordica grosvenori is a complex physiological and biochemical process because the fresh momordica grosvenori is picked and separated, the adjustment of the illumination and the temperature is only needed, the synergistic action conditions of the relative humidity, the oxygen concentration and the temperature are not available, the material basis for promoting the ripening is not available, the fruit failure rate and other factors in the ripening process are not considered, and the scientificity of the momordica grosvenori is to be demonstrated.

In summary, regarding the prior disclosed technical solution for processing the harvested fresh momordica grosvenori to promote the maturation, the prior disclosed technical solution is mainly developed around temperature and illumination, the synergistic effect of relative humidity is ignored, and the applicant finds that the temperature has a certain effect through a comparative experiment, but the illumination has no significant effect on the maturation of the harvested fresh momordica grosvenori. The maturation of the fresh momordica grosvenori is a complex physiological and biochemical process without consideration, so that the basis of chemical components participating in or promoting the maturation is ignored; the point is that the fresh momordica grosvenori is mature, and the phenomena of fruit rot such as rottenness and deterioration in the mature process are not considered.

2, the extraction and separation process technology of mogroside in the prior art

CN201811250821.5 discloses a method for producing high-content mogroside V, which takes frozen momordica grosvenori which is subjected to instantaneous high-temperature heating treatment as a raw material, and 1) pre-treatment: freezing raw material momordica grosvenori, immediately heating at high temperature, freezing the raw material momordica grosvenori at-25 to-10 ℃ for 1 to 2 hours, and immediately heating at 105 to 120 ℃ for 5 to 50 seconds; 2) extraction: peeling the preprocessed fructus momordicae, crushing the pulp, adding water for countercurrent circulation extraction to obtain an extracting solution; 3) and (3) filtering: centrifuging the extracting solution, and filtering the supernatant obtained by centrifuging by using a ceramic membrane to obtain filtrate; 4) adsorption and desorption: adsorbing the filtrate with macroporous resin column, and resolving with ethanol solution to obtain resolving solution; 5) and (3) decoloring: sequentially passing the desorption solution through cation exchange resin and anion exchange resin, and collecting column passing solution; 6) concentration and drying: concentrating and drying the column passing liquid to obtain mogroside V; wherein the content of mogroside V is more than or equal to 50%.

CN201510634737.3 discloses a method for improving purity of mogroside V in mogroside, which takes fresh or dried fruits of Momordica grosvenori as raw materials and comprises the steps of 1) extraction, 2) preconcentration, 3) enzymolysis, 4) primary filtration, 5) resin adsorption, elution, 6) concentration, secondary filtration, 7) resin column desalination, 8) resin column decolorization, 9) activated carbon further decolorization, and 10) sterilization and drying.

CN201410190403.7 discloses a method for extracting mogroside V, which comprises the following steps of taking fresh fruits of momordica grosvenori as raw materials, washing, crushing and extracting: 1) saccharifying fresh momordica grosvenori; 2) water extraction and concentration; 3) settling and centrifuging; 4) macroporous resin adsorption and separation, namely selectively adsorbing by adopting a multi-resin column group, collecting the analytic solution in sections, and combining the analytic solutions in batches according to different contents; 5) refining the ion exchange resin; 6) concentrating and recovering ethanol; 7) refining silica gel; 8) concentrating and spray drying to obtain final product mogroside V extract.

CN201410192274.5 discloses a preparation method of mogroside V. The preparation method uses mature fresh momordica grosvenori fruits as starting raw materials, and momordica grosvenori glycoside V is obtained by crushing, extracting, clarifying, removing impurities, filtering, adsorbing by macroporous adsorption resin, eluting, adsorbing by secondary ion exchange resin, concentrating, drying and refining by ethanol.

The invention discloses a preparation method of high-purity mogroside V, which comprises the following steps: (1) beating fresh fructus Siraitiae Grosvenorii into paste, adding deionized water, heating, performing high-shear extraction, filtering, extracting the residue, mixing the filtrates, and concentrating under reduced pressure to obtain A; (2) separating the A with AB-8 type macroporous adsorbent resin column, eluting with alkaline water to colorless, eluting with deionized water to neutral, eluting with ethanol solution, and concentrating the eluate under reduced pressure to obtain B; (3) separating B with 001 × 16 strong acid styrene cation exchange resin column, eluting with acid water, and concentrating the eluate under reduced pressure to obtain C; (4) separating C with D941 weakly basic anion exchange resin column, eluting with water, concentrating the eluate under reduced pressure to obtain D, and spray drying to obtain mogroside V.

CN200910044558.9 discloses a method for producing a grosvenor momordica extract with mogroside V content of more than 60%. The method comprises the following steps of processing fresh momordica grosvenori: crushing → saccharification → water extraction → concentration → sedimentation and centrifugation → refining of ion exchange resin → refining of macroporous resin → concentration → refining of alumina → concentration → spray drying → process flow of finished product.

CN200710049737.2 discloses a milk white momordica grosvenori extract with mogroside V more than or equal to 40% and mogroside more than or equal to 98% and a preparation method thereof, which takes fresh momordica grosvenori as a raw material and is prepared by water extraction → concentration → enzymolysis → macroporous adsorption resin refining → ion exchange resin decoloration → concentration → spray drying.

In summary, regarding the extraction and separation of mogroside, the process route in the prior art is that the mogroside V with about 50% purity is obtained by the main process steps of clarification, enzymolysis/non-enzymolysis, macroporous adsorption resin refining, ionic resin decoloring, activated carbon decoloring/non-activated carbon decoloring, silica gel refining and the like of a grosvenor momordica extract, and relates to biological enzymolysis, concentration before filtration, silica gel refining and the like, so that the separation and purification of the mogroside V are realized, the removal of phenolic acid components influencing the taste and the taste of the mogroside V is not involved, harmful substances such as pesticide residues, heavy metals, plasticizers and the like in the mogroside V are removed, and the desalination by using macroporous adsorption resin, especially simultaneous desalination and further decoloring under the alkalescent condition is not involved.

3, the bitter taste and the like of the momordica grosvenori are removed in the prior art to improve the taste and the mouthfeel of the momordica grosvenori sweet glycosides

CN201811397385.4 discloses a method for separating mogroside V from fructus momordicae, which comprises the steps of adding water into fructus momordicae, pulping, sequentially carrying out plant enzyme enzymolysis and biological enzyme enzymolysis, collecting enzymolysis liquid, carrying out yeast fermentation after enzyme deactivation, purifying by composite anion and cation exchange resin, concentrating and drying to obtain the mogroside V. The product prepared by the preparation method is snow white, has no bitter taste, little solvent residue, no pesticide residue and stable product quality, and the obtained mogroside V is more than 60 percent and the total glycoside is more than 90 percent. The method only uses anion-cation exchange resin for purification, only uses chemical exchange adsorption, does not have a special macroporous adsorption resin step, can not obtain snow-white mogroside, and still has a certain amount of phenolic acid residue; foreign substances remain, and the alleged no bitter taste cannot be realized; this technique does not result in mogroside V greater than 60%.

Cn201711064166.x discloses a purification method of flavored mogroside V, which comprises the following steps: (1) polyamide adsorption: dissolving the crude extract of mogroside with water, loading onto polyamide resin chromatographic column, and collecting effluent; (2) alkali adjustment and ultrafiltration: adjusting the pH value of the effluent to 8-10, standing, coarsely filtering, ultrafiltering, and collecting the filtrate; (3) ion exchange adsorption: sequentially loading the filtrate on a cation exchange resin column and an anion exchange resin column, and collecting effluent liquid; (4) and (3) decoloring and drying: and (3) passing the effluent through a decolorizing resin column, collecting the effluent, concentrating, and performing spray drying to obtain the flavored mogroside V. In the product obtained by the method, the mass content of mogroside V is more than 60%, the yield is more than or equal to 90%, the mass content of the afterbitter source substance is less than 0.06%, the removal rate is more than 99.5%, no afterbitter exists, and the product is fresh and cool in taste, pure in taste, good in uniformity and stable in property; the method is simple, has strong operability and is suitable for industrial production. The method adopts anion and cation exchange resin for purification, and decolorizes with decolorizing resin, and has the basic principle of introducing foreign substances and residue, and can not completely remove bitter component without afterbitterness, but still has obvious bitter taste and can not be removed.

CN201610860141.X discloses a method for extracting mogroside without bitter taste, which comprises the following steps: 1) dissolving mogroside in water, loading onto DM130 macroporous resin, eluting with water to colorless, eluting with ethanol, collecting ethanol eluate, and recovering ethanol from the eluate to obtain extract; 2) dissolving the extract in water, loading onto D101+ macroporous resin, eluting with water, collecting eluate, concentrating, and drying. The method only uses broad-spectrum macroporous adsorption resin for refining, the two resins have strong adsorption capacity on mogroside, flavone, pigment and the like, separation cannot be realized, phenolic acid substances in mogroside cannot be removed, decoloration cannot be realized, and the product does not have bitter taste and needs further research.

CN201610860168.9 discloses a preparation method of a debitterized fructus momordicae extract, which comprises the following steps: 1) adding fructus Siraitiae Grosvenorii into ethanol for extraction, filtering the extractive solution, and recovering ethanol from the filtrate to obtain extract A; 2) dissolving the extract A in water, adding AB-8 macroporous resin, eluting with water to colorless, eluting with ethanol, collecting ethanol eluate, and recovering ethanol from the eluate to obtain extract B; 3) dissolving the extract B in water, loading onto D101+ macroporous resin, eluting with water, collecting eluate, concentrating, and drying. Compared with the prior art, the fructus momordicae extract prepared by the invention does not contain bitter substances, has pure sweet taste and does not have bitter taste. The method only uses broad-spectrum macroporous adsorption resin for refining, the resin has strong adsorption capacity on mogroside, flavone, pigment and the like, separation cannot be realized, phenolic acid substances in mogroside cannot be removed, and whether the product is debittered or not cannot be decolored needs further research.

CN200710003364.5 discloses a preparation method of a decolored and debitterized fructus momordicae extract, which is characterized in that: using water as solvent, adopting reflux extraction method, filtering and concentrating the extract, decolorizing with decolorizing resin, eluting with ethanol, deodorizing with deodorizing agent, recovering ethanol, concentrating, spray drying, and pulverizing to obtain decolorized and debitterized fructus Siraitiae Grosvenorii extract, which is white and crystalline powder with pure sweet taste and no traditional Chinese medicine taste or afterbitterness, wherein the content of mogroside by weight is above 90%. The method only uses decolorizing resin for refining, and cannot prepare 90% mogroside V; and the decolorizing resin is eluted by ethanol, all components are eluted together, no refining step is actually carried out, mogroside flows out in the feeding process without being exchanged and adsorbed by the decolorizing resin, the pigment is exchanged and adsorbed, and the ethanol eluting part is the components such as the pigment, impurities and the like. The method cannot debitterize mogroside.

In conclusion, the prior art debitterizes mogrosides, mainly involves the steps of enzymolysis, anion-cation exchange resin treatment, macroporous adsorption resin treatment and the like, does not involve debitterizing from the source improvement of the maturity of fresh raw material of the grosvenor momordica, does not involve removing foreign impurities introduced by ion exchange resin decoloration through macroporous adsorption resin, does not involve completely removing phenolic acid, pigment and other components in the mogrosides, which affect the taste and the mouthfeel, and the debitterizing effect needs to be further researched.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects and provide a method for preparing momordica grosvenori sweet glycoside without bitter taste by using momordica grosvenori which cannot naturally mature, old Chinese olive and/or green house sweeping fruit which cannot naturally mature after 11 months are taken as raw materials, and the bitter taste of the momordica grosvenori sweet glycoside is solved from the following three aspects: 1. promoting the ripening of fresh fruits, converting bitter saponin components, and removing bitter taste from the source of raw materials; 2. extracting and separating mogroside with high efficiency, and removing foreign impurities introduced by anion exchange resin decoloration, thereby removing bitter and astringent taste; 3. removing substances affecting taste and flavor such as mogroside and pigment, and further removing bitter taste.

The inventor records in a previous patent CN202111522661.7 that external adenosine triphosphate activates cell activity, cooperates with methionine to induce and stimulate endogenous methionine in fresh fructus momordicae to combine with oxygen, promotes transfer and metabolism of carbohydrate and improves resistance in a maturation process through exogenous jasmonic acid and methyl ester thereof, thereby generating a large amount of endogenous ethylene and protective substances, reducing respiratory injury and bacterial invasion injury of carbon dioxide to fresh fructus momordicae, greatly reducing a fruit damage rate, and improving the maturation degree of fructus momordicae.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a method for preparing momordica grosvenori sweet glycosides without bitter taste from momordica grosvenori which cannot naturally mature takes old Chinese olive and/or broom cypress fruit as raw materials, and comprises the following steps:

(1) internal ripening acceleration: selecting old Chinese olive and/or greenhouse-sweeping fruit from fresh collected fructus Siraitiae Grosvenorii, stacking according to size grade, spraying adenosine triphosphate, methionine, jasmonic acid and/or its methyl ester solution in sequence, and standing for ripening;

(2) external saccharification: standing the ripened fresh momordica grosvenori in a well-ventilated place for 4-6 days for saccharification;

(3) extraction: crushing saccharified fructus momordicae, keeping seeds intact, and carrying out water extraction to obtain an extracting solution;

(4) filtering and clarifying: centrifuging and filtering the extracting solution, heating the centrifugate to 45-65 ℃, and performing cross-flow filtration by using ceramic membrane complete equipment to obtain clear and transparent ceramic membrane clear solution;

(5) membrane separation and resin combined refining: cooling the clear liquid of the ceramic membrane, sequentially performing ultrafiltration, performing broad-spectrum macroporous adsorption resin enrichment on the ultrafiltration permeate, decoloring by using ion exchange resin, and desalting and debitterizing by using the adsorption resin;

(6) the limited components are as follows: concentrating the desalted and debitterized solution obtained in the step (5), removing pesticide residues and heavy metals in special pesticide residue removal resin and special heavy metal removal resin, concentrating again, heating, adding rice bran-derived fatty acid, performing heat preservation extraction, standing, cooling, collecting a water phase, and removing plasticizer;

(7) concentration: concentrating the limited component removing feed liquid obtained in the step (6) to 17-25 Baume;

(8) and (3) drying: drying to obtain the momordica glycosides without bitter taste.

The grosvenor momordica fruit which cannot be naturally matured is mainly old Chinese olive and greenhouse fruit, and is normally harvested after 11 days of the month. For common naturally mature momordica grosvenori, the method has better effect. The criteria for screening old olives and greenhouse-swept olives are well known in the art, and in particular, old olives: the fruit peel is dark green and green, the texture is hard, the smell is green and has no fruity flavor, the fruit flesh is sticky and has no or little sugar thread, and the fruit tastes sweet and bitter; sweeping greenhouse fruits: collected when the momordica grosvenori vine withers or is close to wither and cannot mature, generally the momordica grosvenori vine is small in size and belongs to the same outer fruits. The fruit peel is dark green and green, the texture is hard, the gap between the fruit peel and the fruit pulp is large, the smell is green and astringent, the fruit fragrance is not generated, the fruit pulp is sticky and has no or little sugar thread, and the fruit pulp tastes sweet and bitter.

In the step (1), the sizes and the like of the momordica grosvenori are special fruit measuring plates which are standards known by the momordica grosvenori industry. The size of the fruits and the like are the pricing mode in the sale of the momordica grosvenori, the price is mainly determined by the size, and the effect of the maturity of the momordica grosvenori is not obviously influenced and distinguished; and the stacking height of the fresh momordica grosvenori stored in the warehouse is 3-5 layers of the momordica grosvenori. The excessive accumulation causes the waste of storage space, and is not beneficial to the accumulation of volatile substances of the fresh momordica grosvenori in the basket in the maturation process and the maturation promotion among the momordica grosvenori; if the height is too high, the bearing capacity is easy to exceed the bearing range of the standard fructus momordicae basket, and the fresh fructus momordicae is easy to crush so as to increase the fruit damage rate.

In the step (1), the warehouse standard is to set a raw lime point and a saturated lime water point, carry out air exchange at regular time and control the stacking height, the temperature and the relative humidity; further, the lime points are every 4-5 m²Setting 1 lime point and 1 saturated lime water point, wherein the distance between the lime point and the saturated lime water point is more than 1 meter. The quicklime can absorb excessive water vapor in the air and generate certain heat to keep relatively constant humidity and temperature in the warehouse; the saturated lime water can absorb carbon dioxide generated by the fresh momordica grosvenori in the storehouse due to respiration, so that the respiratory damage of the carbon dioxide to the fresh momordica grosvenori is reduced, and the bad fruit rate is obviously reduced; the timing ventilation is to enable the oxygen to reach the level close to the air (namely about 20%) when the volume concentration of the oxygen is 10-12%. Under the condition in the warehouse, the air is exchanged once in about 22-26 hours to promote the maturation of the fresh momordica grosvenori. The temperature of the storehouse is 20-26 ℃, and the relative humidity is 75-90%. Under the conditions of temperature and humidity, the maturation of the momordica grosvenori can be remarkably promoted by combining with an external additive substance.

In the step (1), the spraying sequence of the three medicaments, namely adenosine triphosphate, methionine, jasmonic acid and/or methyl ester solution thereof cannot be changed, adenosine triphosphate is used for activating cell activity, exogenous methionine is further used for activating methionine in endogenous protein and promoting the methionine to be combined with oxygen, and jasmonic acid and methyl ester thereof are used for improving metabolism and generating protective substances so as to improve resistance. The technical effects of improving the maturity, reducing the bad fruit rate and having good taste and mouthfeel of the mature fructus momordicae are not achieved by changing the reagent spraying sequence.

Preferably, in the step (1), the concentration of adenosine triphosphate is 350-500 ppm, the concentration of methionine is 900-1100 ppm, and the concentration of jasmonic acid and methyl ester thereof is 400-600 ppm. The concentration of the sprayed agent cannot be too high or too low, and the concentration is too low, so that the spraying volume is too large, water is accumulated in fresh fruits (the water quantity carried by the surface of the fresh momordica grosvenori is limited), the relative humidity in the air is too high, the absorption of quicklime to water and the conversion of quicklime into slaked lime are influenced, the maturation period is prolonged, and mildewed fruits are more easily generated; the concentration is too high, the spraying volume is too small, so that the fresh momordica grosvenori is not wet enough, the relative humidity in the air is low, and the quicklime absorbs less moisture, so that the heat production is low, and the maturation of the fresh momordica grosvenori is not facilitated.

Preferably, in the step (1), the spraying time interval of the three reagents is 1-5 hours, preferably 2-3.5 hours, different reagents are sprayed at a certain time interval, so that the reagents can be fully contacted with the momordica grosvenori cells and then sprayed with another substance on the premise that the solution of the former substance soaks the surface of the fresh momordica grosvenori, and a certain time difference is controlled, thereby being beneficial to exerting a synergistic linkage effect. Too short a time interval is not favorable for the sufficient absorption of the latter substance, and too long a time interval is not favorable for the synergistic linkage effect between different substances.

Preferably, in the step (1), the ripening condition is that the relative humidity is 75-90% at 20-26 ℃, and the ripening time is 160-170 h; more preferably, the temperature and humidity gradient is gradually reduced during the ripening of step (3).

In a preferred embodiment of the present invention, three exogenous agents are sprayed according to the following procedure: I. 0-1 h and 72-74 h: spraying adenosine triphosphate solution; 2-3 h and 74-76 h: spraying methionine solution; 4-6 h and 77-80 h: spraying jasmonic acid and methyl ester solution.

In a more preferred embodiment of the present invention, the temperature and humidity are set according to the following procedure: 0 to 100-110 h: the temperature is 23-26 ℃, and the relative humidity is 85-90%; 100-110-140-150 h: the temperature is 23-26 ℃, the absolute value of the relative humidity is reduced by 2-10%, preferably by 3-7%; 140-150h to the end of ripening: the temperature is 20-23 ℃, and the absolute value of the relative humidity is reduced by 2-10%, preferably 3-7%. With the storage of the fresh momordica grosvenori, the water in the fresh momordica grosvenori is gradually evaporated and lost, the maturity is gradually improved, the environmental temperature and the humidity are reduced, the internal environment and the external environment of the fresh momordica grosvenori can be well coordinated, the whole maturation is facilitated, and the maturation with uniform surface color is obtained; in addition, the environmental temperature and humidity are gradually reduced, the fruit damage rate is reduced, and the damage of high temperature and humidity to fresh fruits is reduced.

Preferably, in the step (2), the external saccharification condition is good ventilation, so that direct sunlight and rain are avoided; stacking 4-5 baskets in height, and stacking 4-6 baskets in length and width; standing for 4-6 days; the condition for completing saccharification is that more than 65% of the fruit surface is yellow, and the weight of the fruit is 85-92% of that before standing. After the siraitia grosvenori which can not be ripened naturally is ripened in the storehouse, the quality of the siraitia grosvenori which can not be ripened naturally is equivalent to that of the siraitia grosvenori which is ripened normally. Because the temperature and humidity in the ripening accelerating process are greatly different from the external natural conditions, in order to keep the consistency of the production process, the fruits need to be stored for a period of time under the external natural conditions, so that the water in the fruits is further evaporated, the fruits after ripening are further cured, more sugar substances are generated and accumulated, the taste and the mouthfeel are better, the color of the fruit peels is further yellowed, the yellow ripening is realized, and obvious sugar threads are picked up by the pulp.

Preferably, in step (3), the water extraction includes, but is not limited to, continuous countercurrent extraction, extraction tank extraction.

Further, the conditions of the continuous countercurrent extraction are: temperature: 10-95 ℃; time: 2-3 h; adding water: 1.2-3.0 times (water volume/fresh fructus momordicae, V/W); two extraction tanks, each of which is extruded and filtered after extraction, and the continuous extracted extracting solution is combined to obtain the countercurrent extracting solution.

The extraction conditions of the extraction tank are as follows: temperature: 10-95 ℃; time: 1.5-2.5, 1.0-2.0 and 0.5-1.5 hours; the times are as follows: 3 times; adding water: 2-4 times (water volume/fresh fructus momordicae, V/W) each time; stirring mode: mechanical stirring or compressed air back flushing is started. Filtering after each extraction, extracting residue for the 1 st and 2 th times for the next extraction, and mixing extractive solutions for 1 and 2 times to obtain extractive solution in extraction tank.

Preferably, in the step (4), the filtration is a combination of horizontal screw centrifugation, disc centrifugation and ceramic membrane clarification at a temperature of 45-65 ℃. Wherein the ceramic film is made of alumina or zirconia, and the aperture is 50-800 nm.

The fresh fructus momordicae contains macromolecular substances such as pectin, protein and the like, is easy to deposit and adhere at a lower temperature, and can obviously block a ceramic membrane if the temperature of the ceramic membrane is low.

Preferably, in the step (5), the ultrafiltration membrane decolorization, the first broad-spectrum adsorption resin enrichment, the ion exchange resin decolorization, the second broad-spectrum adsorption resin desalination and debitterizing and the special adsorption resin debitterizing for the phenolic acid are sequentially carried out. Wherein, the decolorization is the combination of an ultrafiltration membrane, ion exchange resin and macroporous adsorption resin, the purification is the combination of broad-spectrum adsorption resin and ion exchange resin, the desalination is the chromatography of second broad-spectrum adsorption resin, and the debitterizing is the combination of the 2 nd-time broad-spectrum adsorption resin and special adsorption resin.

Mogroside as triterpene saponin with molecular weight of about 1300 can permeate an ultrafiltration membrane with certain molecular weight cut-off, but part of pigment is cut off due to large molecular steric hindrance, and the other part of pigment and mogroside permeate together. Part of the pigment is separated by the ultrafiltration membrane, so that the decolorizing effect of the resin is improved. And adjusting the pH value of the feeding liquid of the first broad-spectrum adsorption resin to be about 5-6.5, wherein the mogroside, phenolic acid and pigment can be well adsorbed within the pH range, but reducing sugar such as glucose and fructose, and substances such as protein are not adsorbed and separated. The anion exchange resin has exchange adsorption effect on phenolic acid substances, the ion exchange resin with a certain specification and model has good decoloration effect, and the mogroside is a neutral substance of triterpenoid saponins and is not adsorbed by the ion exchange resin, so that the separation of the mogroside from most of phenolic acid and pigment is realized. But the effluent liquid still contains partial phenolic acid and pigment, the pH value of the ion exchange resin is adjusted to be 8-9.5, the second broad-spectrum macroporous adsorption resin has good adsorption on mogroside as a neutral substance under the alkalescent condition, but a small amount of phenolic acid is also adsorbed, the salt substances generated by the exchange adsorption of the rest phenolic acid, pigment and ion exchange resin are not adsorbed and flow out under the alkalescent condition, and the salt substances generated by the exchange adsorption of the ion exchange resin can be completely removed through the further separation of the macroporous adsorption resin, so that the bitter taste of the mogroside is further removed. The special adsorbent resin for phenolic acid has specific selective adsorption on phenolic acid, basically has no adsorption or little adsorption on mogroside, can further realize basically complete adsorption on residual phenolic acid substances without regulating the pH value again under the alkaline condition of weak effluent of the second broad-spectrum macroporous adsorbent resin, thereby removing bitter substances which influence the taste and the mouthfeel of the mogroside for the third time.

The ultrafiltration membrane decolorization is mainly used for removing pigments with large steric hindrance and improving the decolorization effect of the ion exchange resin; the first broad-spectrum adsorption resin is mainly used for adsorbing mogroside, phenolic acid and pigment to realize the enrichment of mogroside; the ion exchange resin is mainly used for exchanging and adsorbing most of phenolic acid and pigment, so that the purity of the mogroside is further improved, but part of the phenolic acid and the pigment cannot be completely exchanged and adsorbed; after the second broad-spectrum adsorption resin is subjected to ion exchange resin, the feed liquid is weakly alkaline, mogroside is completely adsorbed, phenolic acid and pigment are further removed under alkaline conditions, and salt substances in the alkaline solution can be completely removed through purification and water washing, so that double effects of decolorization and desalination are realized; the special adsorption resin for the acid phenol is mainly phenolic acid which adsorbs micromolecules and is not adsorbed by ion exchange resin, and has specific selective adsorption on phenolic acid substances.

Furthermore, the temperature for decoloring the ultrafiltration membrane is below 40 ℃, the molecular weight cut-off of the membrane is more than or equal to 50KD, and the collected part is permeate. The ultrafiltration membrane with a certain molecular weight cut-off has a good decolorization effect at the temperature below 40 ℃, and because the molecular weight of the mogroside is about 1300 and the mogroside is a triterpenoid, part of the pigment and the mogroside permeate the ultrafiltration membrane;

the first broad spectrum adsorption resin and the second broad spectrum adsorption resin can be the same or different, and preferably the same broad spectrum macroporous adsorption resin is adopted, such as D101, LX-100B, LX-T28, LX-T81 and weak polarity AB-8; adjusting the pH value of the first broad-spectrum adsorption resin feeding liquid to about 5-6.5, wherein the mogrosides, the phenolic acid and the pigment can be well adsorbed under the weak acidic condition; and adjusting the pH value of the feed liquid of the second broad-spectrum adsorption resin to be about 8-9.5, wherein the feed liquid is in alkalescence, mogroside serving as a neutral substance is adsorbed, a small amount of phenolic acid is also adsorbed, and the rest of phenolic acid, pigment and salt substances generated by ion exchange adsorption of the ion exchange resin are not adsorbed and flow out under the alkalescence condition.

The ion exchange resin is alkaline anion resin, including gel type and macroporous acrylic acid weak base anion resin, acrylic acid series strong base and weak base anion resin, gel type and macroporous styrene series strong base anion resin, macroporous acrylic acid strong base anion resin, macroporous styrene series weak base anion resin, the preferred model: d900, D941, D316, D296, D280.

The specification and model of the special phenolic acid adsorption resin is one or any combination of a nonpolar styrene material LXD-200, a polar polyamide material LX-8, an acrylic acid material LX-17 and a styrene brominated resin LX-207. The resin has specific and selective adsorption on phenolic acid, basically has no adsorption or little adsorption on mogroside, and can be further processed to recover a small amount of mogroside. The column liquid of the special phenolic acid adsorption resin is alkalescent, under the pH condition, the mogroside as a neutral substance flows out without being exchanged and adsorbed, and most of the phenolic acid and the pigment are exchanged and adsorbed.

In the step (6), the limited components comprise harmful substances such as pesticide residues, heavy metals, plasticizers and the like. Because the momordica grosvenori is difficult to use pesticides in the planting process, the momordica grosvenori can accumulate heavy metals in the growth process, and the momordica grosvenori glycoside is correspondingly limited by the limited components when resin is used in the production and processing processes: pesticide residues, heavy metals and plasticizers. In the process steps of the method, the pesticide residues and the heavy metals are basically and completely removed through combined treatment of the adsorption resin and the ion exchange resin for 2 times in the earlier step, and then the pesticide residues and the heavy metals are further treated by special resin for removing the pesticide residues and the heavy metals, so that the pesticide residues can be completely removed, and the content of the heavy metals is further reduced. The rice bran-derived fatty acid is a by-product produced during the refining of rice bran oil, is immiscible with water, is liquid in a hot state, and is solid at normal temperature. The applicant finds that the momordica grosvenori glycoside plasticizer has a good dissolving effect on the plasticizer, the separation of an oil phase and a water phase can be further realized through the change of the temperature, and the momordica grosvenori glycoside is kept in the water solution.

Further, the special resin for removing pesticide residues and heavy metals comprises gel type and macroporous acrylic resin, gel type and macroporous styrene resin, macroporous acrylic resin, macroporous styrene resin and acrylic gel resin. The preferable model of the pesticide residue removing resin is as follows: LSA-900B, LSA-900D; the preferred types of heavy metal removal resin are as follows: LX-500, LX-800 and LSC-As. Before entering special resin for removing pesticide residues and heavy metals, the feed liquid is concentrated by a reverse osmosis membrane until the content of solid matters is 6-12%. Through the combined treatment of the two times of adsorption resin and ion exchange resin in the earlier step, the pesticide residue and the heavy metal are basically and completely removed, and the pesticide residue and the heavy metal special resin are used for further treatment, so that the complete removal of the pesticide residue can be realized, and the content of the heavy metal is further reduced. The plasticizer is removed, and the used reagent is rice bran derived fatty acid; concentrating the feed liquid with pesticide residues and heavy metals removed by the reverse osmosis membrane to the solid content of 14-18%, continuously stirring, heating to 60-75 ℃, adding the rice bran-derived fatty acid with the volume of 0.4-1.0 time (V/V) of the concentrated feed liquid, preserving heat, standing, cooling, and collecting the water phase. The rice bran-derived fatty acid is immiscible with water, is liquid in a heated state, and is solid at normal temperature. The applicant finds that the momordica grosvenori glycoside plasticizer has a good dissolving effect on the plasticizer, the separation of an oil phase and a water phase can be further realized through the change of the temperature, and the momordica grosvenori glycoside is kept in the water solution.

Further, the concentration in the step (7) is carried out at a temperature of 50-65 ℃ and a vacuum degree of-0.1-0.05 MPa until 17-25 Baume is obtained.

Further, the drying in the step (8) is carried out by spray drying or microwave vacuum drying, preferably spray drying, under the conditions that the air inlet temperature is 170-.

The invention carries out a series of operations after ripening of grosvenor momordica fruit (old Chinese olive and/or broom cypress fruit) which can not ripen naturally in the storehouse, and finally the obtained mogrosides are close to the level of the mogrosides extracted from normal grosvenor momordica fruit. Through the combination of the process technology, the momordica grosvenori glycoside without bitter taste is prepared from the momordica grosvenori which cannot be naturally matured, wherein the purity of the momordica grosvenori glycoside V is more than or equal to 50%.

The invention has the beneficial effects that:

(1) the invention provides a method for preparing bitter-taste-free momordica glycoside by using momordica grosvenori which cannot be naturally matured. The momordica grosvenori which is collected in 11 th-month middle ten days and cannot naturally mature is used as a raw material, the bitter taste of the momordica grosvenori sweet glycosides is solved from the source of the raw material through internal ripening acceleration and external saccharification, unknown substances such as salts with bitter taste and the like generated by ion exchange resin and phenolic acids coexisting with the momordica grosvenori sweet glycosides are removed through a membrane separation and resin combined technology, and thus the momordica grosvenori sweet glycosides without the bitter taste are prepared.

(2) The invention provides a ripening method of fresh momordica grosvenori. The method changes the prior art that fruits and vegetables are ripened by adjusting temperature, illumination and carbon dioxide or by exogenous ethylene directly, reduces the concentration of carbon dioxide by controlling the proper temperature, humidity and oxygen concentration in a storehouse, and stimulates the combination of endogenous methionine and oxygen of the fresh momordica grosvenori by the synergistic effect of exogenous methionine on adenosine triphosphate, jasmonic acid and methyl ester thereof, so that the endogenous ethylene is generated, the resistance is improved and the bad fruit rate is reduced while the ripening of the fresh momordica grosvenori is remarkably promoted. The ripening method can ripen the momordica grosvenori which can not ripen naturally, particularly the old Chinese olive and the broom cypress fruit, greatly improve the ripening degree of the old Chinese olive and the broom cypress fruit, has low fruit-destroying rate and high mogroside V content, and the taste of the ripened momordica grosvenori which can not ripen naturally is close to that of the common momordica grosvenori.

(3) The method solves the problem that the momordica grosvenori which can not be naturally mature is mature after being harvested, so that the old Chinese olive and/or the greenhouse fruit can be used as raw materials for producing the momordica grosvenori sweet glycosides to be applied to the plant extraction industry instead of being limited to baking the dried momordica grosvenori. The fresh fructus momordicae which can be used for extracting the mogroside not only has good taste, but also has higher content of the mogroside V, so the application range of old Chinese olive and greenhouse fruit is expanded, and the development of the fructus momordicae industry is promoted.

(4) The method of the invention not only breaks through the technical bottleneck that the purity V of the mogroside cannot be more than or equal to 50% and the finished product mogroside has bitter taste in the prior art, but also enables the content of limited components such as heavy metal, pesticide residue, plasticizer and the like to be lower than the national standard by 50%, thereby realizing the industrialized scale production of the ecological green mogroside serving as a food additive.

Detailed Description

The present invention will be further described with reference to the following examples.

The fresh momordica grosvenori used in the embodiment of the invention is purchased in Jingzhou county of Huai city, Hunan province, and the harvesting time is 12 months.

The quicklime, methionine, adenosine triphosphate, jasmonic acid and methyl ester thereof used are obtained by conventional commercial routes if not specified; the saturated limewater is prepared by adding tap water into quick lime.

The used purified water is prepared by secondary pure water equipment used in a production workshop, and the used macroporous adsorption resin, anion exchange resin, special adsorption resin for phenolic acid, special resin for removing pesticide residues and heavy metals and rice bran-derived fatty acid are all obtained by conventional commercial approaches if no special description is provided.

In the embodiment of the invention, the content of mogroside V is determined by High Performance Liquid Chromatography (HPLC) according to '2020 edition of Chinese pharmacopoeia'; the taste and mouthfeel of mogroside are determined by perception.

Example 1

1. And (5) placing in the container to accelerate ripening.

(1) And selecting fruits and warehousing. Firstly, 1500kg of old Chinese olive and greenhouse fruit are manually selected from harvested fresh momordica grosvenori, the fruits are divided into 5 grades of special fruits, big fruits, medium fruits, small fruits and outer fruits according to the sizes by using momordica grosvenori measuring plates, and then the intact fruits, the fruits without damage and mildew are selected and separated according to the following standards: 240 small fruits/basket, 180 medium fruits/basket, 140 big fruits/basket; the weight of the special fruits and the external fruits is 14.0 kg/basket. And (5) basket filling, and warehousing and stacking according to grades.

(2) Library criteria. Stacking height: 5 layers of siraitia grosvenorii standard baskets; and (3) timing ventilation: ventilating every 24h for 1 time; lime point: every 5.0m²Setting 1 lime point and 1 saturated lime water point, wherein each point releases 3.5kg lime and 3.0L saturated lime water (containing calcium hydroxide precipitate).

(3) Adenosine triphosphate, methionine, jasmonic acid and methyl ester solution were sprayed according to the following procedures and conditions.

0.1 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 2.1 h: spraying methionine solution with concentration of 1100 ppm; 4.5 h: spraying jasmonic acid solution with the concentration of 600 ppm; 72.5 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 75.0 h: spraying methionine solution with concentration of 1100 ppm; 78.5 h: spraying jasmonic acid solution with the concentration of 600 ppm; the spraying amount of the medicament is about 80mL per kilogram of fructus momordicae.

0-108 h: the temperature is 26 +/-1 ℃, and the relative humidity is 87%; 108-144 h: the temperature is 24 +/-1 ℃, and the relative humidity is 84%; 144-168 h: the temperature is 22 +/-1 ℃, and the relative humidity is 77%.

(4) Time: inspecting at 160h, finding that the peel of more than 93% of fresh fructus Siraitiae Grosvenorii turns into mung bean yellow, pressing pulp with hand to remove sticky thread, and ripening and taking out.

Inspecting, wherein the bad fruit rate of the fresh momordica grosvenori discharged from the warehouse is 0.68% in the step of internal ripening; the taste of the tasted pulp is pure, has no bitter taste and astringent taste, and has basically the same taste and mouthfeel as the taste of the naturally grown mature fresh momordica grosvenori.

2. External saccharification.

Placing the internal ripened momordica grosvenori in a well-ventilated shed, stacking the momordica grosvenori in 5 layers, wherein each stack is 5 baskets long and wide, and a distance of 50cm is kept between the stacks. Inspecting at any time, standing for 6 days, and finding that more than 70% of the fresh fructus Siraitiae Grosvenorii has yellow surface, the weight of the fruit is 90% of that before standing, and peeling with hands to press pulp to obtain obvious sugar threads, so as to reach the standard of extracting fresh fructus Siraitiae Grosvenorii.

3. And (4) extracting.

Crushing the saccharified fresh fructus Siraitiae Grosvenorii with fructus Siraitiae Grosvenorii crusher while keeping seeds intact, and conveying the crushed material to 6m³The extraction tank is used for extracting with tap water.

The operating conditions are as follows: the temperature is 90 ℃; time: 2.0, 1.5 and 0.5 h; the times are as follows: 3 times; adding water: 4000L, 3000L, 4000L; stirring mode: compressed air is started to recoil for 5min every 15 min. Filtering after each extraction, extracting residue for the 1 st and 2 th times for the 3 rd time, collecting the 3 rd time extractive solution in another container, and mixing the 1 st and 2 rd time extractive solutions to obtain 6200L extractive solution.

4. And (5) filtering and clarifying.

And (3) reducing the temperature of the extracting solution to 53 ℃ through a plate heat exchanger, performing horizontal spiral sedimentation centrifugation, performing disc centrifugation, and finally performing ceramic membrane complete equipment with the material of zirconium oxide and the aperture of 500nm to obtain clear and transparent ceramic membrane clear solution.

5. Refining by combining membrane separation and resin.

(1) And (5) decolorizing with an ultrafiltration membrane. And (3) cooling the clear solution of the ceramic membrane to 32 ℃ by using a plate heat exchanger, passing through ultrafiltration membrane complete equipment with the molecular weight cutoff of 50KD, and collecting the permeate to obtain the decolorized solution of the ultrafiltration membrane.

(2) And (4) enriching the broad-spectrum adsorption resin. The stainless steel chromatographic column is filled with 700kg of D101 macroporous adsorption resin in advance, and the regeneration treatment is carried out for standby. Adjusting pH of ultrafiltration membrane decolorization solution to 6.5 with saturated limewater, introducing into resin column, washing resin column with 3500L purified water after feeding till effluent liquid is clear and transparent and nearly colorless, desorbing with 1800L 65% edible ethanol, and collecting desorption solution. Concentrating under reduced pressure at vacuum degree of-0.09 MPa and temperature of 62 deg.C, recovering ethanol until no alcohol smell exists, and collecting the adsorption resin enriched solution.

(3) Decolorizing with ion exchange resin. The stainless steel chromatographic column lined with plastic inside is filled with 150kg of D941 weak base anion exchange resin and is regenerated with acid and alkali for later use. And (3) feeding the enrichment solution of the adsorption resin into a resin column, washing the resin column with 1200L of purified water after feeding till the effluent liquid tastes no sweet through mouth, and sequentially collecting the feed effluent liquid and the water washing column liquid.

(4) The broad-spectrum adsorption resin is desalted and debitterized. 240kg of white D101 macroporous adsorption resin which does not adsorb pigments is filled in a stainless steel chromatographic column in advance, and is treated by 80 percent ethanol and purified water for standby. Adjusting pH of the combined solution of the feed effluent of the ion exchange resin column and the column washing solution to 9.5, feeding into the resin column, washing the resin column with 1000L of purified water after feeding until the effluent is clear, transparent and colorless, desorbing with 680L of 60% edible ethanol, and collecting the desorption solution. Concentrating under reduced pressure at a vacuum degree of-0.09 MPa and a temperature of 63 deg.C to recover ethanol until no alcohol smell exists, and obtaining the adsorption resin desalting and debittering liquid.

(5) The special adsorption resin for the acid phenol is debittered. 1.8kg of LX-8 macroporous adsorption resin is filled in a stainless steel chromatographic column in advance, and the treatment is carried out for standby. And (3) feeding the adsorption resin desalting and debittering liquid into a resin column, washing the resin column with 5L of purified water after feeding, collecting feeding effluent liquid and washing liquid, and combining to obtain the special adsorption resin debittering liquid.

6. And (4) removing limited components.

(1) Removing pesticide residue and heavy metal. 1.5kg of LSA-900D pesticide residue removal resin and 1.5kg of LX-800 heavy metal removal resin are filled in a stainless steel chromatographic column in advance and are treated for later use. Concentrating the special adsorption resin debitterizing solution to solid content of 10% by using a reverse osmosis membrane, sequentially passing the membrane concentrated solution through an LSA-900D resin column and an LX-800 resin column, feeding the materials, sequentially passing 9L of purified water through the resin columns, collecting feed effluent liquid and water washing liquid, and combining the feed effluent liquid and the water washing liquid to obtain the pesticide residue and heavy metal removing liquid.

(2) And (4) removing the plasticizer. Concentrating the pesticide residue and heavy metal removing solution by using a reverse osmosis membrane until the solid content is 15%, continuously stirring, heating to 70 ℃, adding 4.5kg of rice bran-derived fatty acid, keeping the temperature for 3h, standing, cooling to room temperature by using circulating water, layering solid and liquid, and collecting a water phase to obtain plasticizer removing solution.

7. And (5) concentrating.

Concentrating under reduced pressure at a vacuum degree of-0.09 MPa and a temperature of 63 ℃ to remove the plasticizer liquid to 18 Baume, and obtaining a vacuum concentrated solution.

8. And (5) drying.

The air inlet temperature of spray drying is adjusted to 187 ℃, the air outlet temperature is adjusted to 85 ℃, and the vacuum concentrated solution is dried to obtain 10.6kg of mogroside.

Through detection, the finished product mogroside V content is 54.11%, the finished product mogroside is white powder, pesticide residues and plasticizer are not detected, and arsenic is 0.03ppm and lead is 0.05 ppm. Dissolving finished mogroside in water, preparing the finished mogroside into 3 wt% of cane sugar with the same sweetness, asking a subject to taste, comprehensively scoring and evaluating the smell and taste of a solution of a sweetening agent, wherein the score is 1-10, the 3 wt% of cane sugar solution is used as a reference, the satisfaction degree of 5% of cane sugar solution is 10 scores at the highest and 1 score at the lowest, the number of questionnaire testers in each survey is 12, removing one highest score and one lowest score, and finally, the average value of the whole is obtained. Specifically, the solution to be evaluated is placed in a disposable paper cup, is held in the mouth by sensory evaluation personnel and is spitted out after staying for several seconds, the evaluation time interval is 20min, and the evaluation result is the average value of scores of 10 evaluation personnel. The results are shown in table 1 below.

Example 2

The other operations and conditions were the same as in example 1 except that in (3) of step 1, (-) 350ppm of an adenosine triphosphate solution, 900ppm of a methionine solution, 400ppm of a jasmonic acid solution, and 100mL of a solution per kg of Siraitia grosvenorii were sprayed.

Example 3

The other operations and conditions were the same as in example 1 except that in (3) of step 1, 0.1 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 1.8 h: spraying methionine solution with concentration of 1100 ppm; 3.5 h: spraying jasmonic acid solution with the concentration of 600 ppm; 73.0 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 74.5 h: spraying methionine solution with concentration of 1100 ppm; 77.0 h: spraying jasmonic acid solution with the concentration of 600 ppm; the spraying amount of the medicament is about 80mL per kilogram of fructus momordicae.

Example 4

The other operations and conditions were the same as in example 1 except that in (3) of step 1, 0.1 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 4.0 h: spraying methionine solution with concentration of 1100 ppm; 8.0 h: spraying jasmonic acid solution with the concentration of 600 ppm; 72.0 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 75.5 h: spraying methionine solution with concentration of 1100 ppm; 80.0 h: spraying jasmonic acid solution with the concentration of 600 ppm; the spraying amount of the medicament is about 80mL per kilogram of fructus momordicae.

Example 5

Other operations and conditions are the same as those in the example 1, except that in the step (3) of the step 1, the temperature is kept at 24 +/-1 ℃ for 0-168 hours, and the humidity is 85%.

Example 6

The other operations and conditions were the same as in example 1, except that (5) of step 5 was eliminated, i.e., no dedicated adsorption resin debittering was performed.

Example 7

The other operations and conditions were the same as in example 1, except that (4) of step 5 was eliminated, i.e., the desalting and debittering with the broad spectrum adsorbent resin was not carried out.

Example 8

The other operations and conditions were the same as in example 1 except that in (2) of step 5, the ultrafiltration membrane decolorization solution pH was adjusted to 5, and in (4) of step 5, the combined solution pH of the feed effluent of the ion exchange resin column and the water-washed column solution was adjusted to 8.

Example 9

The other operations and conditions were the same as in example 1 except that in (2) of step 5, the ultrafiltration membrane decolorization solution pH was adjusted to 8, and in (4) of step 5, the combined solution pH of the feed effluent of the ion exchange resin column and the aqueous column wash was adjusted to 7.

Comparative example 1

The other operations and conditions were the same as in example 1, except that step 2 was eliminated, i.e.no external saccharification was carried out.

Comparative example 2

The other conditions were the same as in example 2 except that in (3) of step 1, the adenosine triphosphate solution was not sprayed.

Comparative example 3

The other conditions were the same as in example 2 except that in (3) of step 1, the methionine solution was not sprayed.

Comparative example 4

The other conditions were the same as in example 2 except that in (3) of step 1, no jasmonic acid solution was sprayed.

Comparative example 5

Other conditions were the same as in example 2 except that (3) in step 1 was: 0.1 h: spraying methionine solution with concentration of 1100 ppm; 2.0 h: starting to spray 500ppm adenosine triphosphate solution; 4.1 h: spraying jasmonic acid solution with the concentration of 600 ppm; 72.5 h: spraying methionine solution with concentration of 1100 ppm; 74.2 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 78.0 h: spraying jasmonic acid solution with the concentration of 600 ppm; the spraying amount of the medicament is about 80mL per kilogram of fructus momordicae.

Comparative example 6

Other conditions were the same as in example 2 except that (3) in step 1 was: spraying jasmonic acid solution with the concentration of 600 ppm; 2.0 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 4.1 h: spraying methionine solution with concentration of 1100 ppm; 72.5 h: spraying jasmonic acid solution with the concentration of 600 ppm; 74.2 h: starting to spray adenosine triphosphate solution with the concentration of 500 ppm; 78.0 h: spraying methionine solution with concentration of 1100 ppm; the spraying amount of the medicament is about 80mL per kilogram of fructus momordicae.

Comparative example 7

The other operations and conditions were the same as in example 1 except that (3) of step 5 was eliminated, that is, the ion exchange resin decolorization was not performed.

Comparative example 8

The other operations and conditions are the same as those in the example 1, except that in the step 6 (1), the debitterized solution is not concentrated and directly enters special resin for removing pesticide residues and heavy metals; in the step (2) of the step 6, the pesticide residue and heavy metal removing liquid is not concentrated, and rice bran-derived fatty acid is directly added under the condition of heating and stirring.

Comparative example 9

The other operations and conditions were the same as in example 1 except that in step 5, (2) and (3) were reversed in order, i.e., ion exchange resin decolorization was performed first and then broad spectrum adsorbent resin enrichment was performed. For the decolorization which is needed greatly, the dosage of the ion exchange resin needs to be increased obviously, the cost is increased, and the decolorization effect is not good.

Application example

TABLE 1

Therefore, the method of the invention accelerates the ripening of the green fruits and/or the old Chinese olive fruits of the grosvenor momordica fruit which is difficult to naturally ripen, the fruit-breaking rate is low, the content of mogroside V in the obtained grosvenor momordica fruit with high ripeness degree is high, the content of bitter substances is low, and the taste is close to that of the normal common grosvenor momordica fruit. The finally prepared momordica grosvenori glycoside V50 product has high yield of the mogroside V and good sensory experience of tasters, and the method widens the application of raw materials which are difficult to utilize of momordica grosvenori and reduces the cost of momordica grosvenori enterprises. The data in table 1 show that, when the greenhouse fruits and/or the old Chinese olive fruits are ripened, the addition amount and the sequence of the ripening exogenous reagents, the temperature and the humidity of the storage and the like all have different degrees of influence on the ripening process of the momordica grosvenori. In addition, in the subsequent stage, the external saccharification step, some parameters of the debittering, decoloring and desalting step, such as the pH value, also have certain influence on the quality of finally obtained mogrosides. In the preferred embodiment of the invention, the parameters are optimized, and finally, the mogrosides which are close to the common momordica grosvenori and are end products are prepared by sweeping green fruits and old green fruits which are difficult to mature under natural conditions or adopting a common momordica grosvenori ripening method.

Claims

1. A method for preparing momordica grosvenori sweet glycosides without bitter taste from momordica grosvenori which cannot naturally mature takes old Chinese olive and/or broom cypress fruit as raw materials, and comprises the following steps:

2. The method according to claim 1, wherein in the step (1), the library standard is setting a raw lime point and a saturated limewater point, timing ventilation, controlling the stacking height, the temperature and the relative humidity; further, the lime points are every 4-5 m²Setting 1 lime point and 1 saturated lime water point, wherein the distance between the lime point and the saturated lime water point is more than 1 m; the timing ventilation is that when the volume concentration of oxygen is 10-12%, the ventilation makes the oxygen reach the level close to air.

3. The method according to claim 1, wherein in the step (1), the concentration of adenosine triphosphate is 350 to 500ppm, the concentration of methionine is 900 to 1100ppm, and the concentration of jasmonic acid and methyl ester thereof is 400 to 600 ppm.

4. The method according to claim 3, wherein in the step (1), the three reagents are sprayed for 1-5 h, preferably 2-3.5 h.

5. The method as claimed in claim 1, wherein in the step (1), the ripening condition is 20-26 ℃, the relative humidity is 75-90%, and the ripening time is 160-170 h; preferably, the temperature and humidity gradient is gradually reduced during the ripening of step (3).

6. The method of claim 4, wherein three exogenous agents are sprayed according to the following procedure: I. 0-1 h and 72-74 h: spraying adenosine triphosphate solution; 2-3 h and 74-76 h: spraying methionine solution; 4-6 h and 77-80 h: spraying jasmonic acid and methyl ester solution;

preferably, the temperature and humidity are set according to the following program: 0 to 100-110 h: the temperature is 23-26 ℃, and the relative humidity is 85-90%; 100-110-140-150 h: the temperature is 23-26 ℃, the absolute value of the relative humidity is reduced by 2-10%, preferably by 3-7%; 140-150h to the end of ripening: the temperature is 20-23 ℃, and the absolute value of the relative humidity is reduced by 2-10%, preferably 3-7%.

7. The method according to claim 1, wherein in step (2), the conditions of the external saccharification are well ventilated and protected from direct sunlight and rain; stacking 4-5 baskets at the height, and standing for 4-6 days for each basket with the length and the width; and/or

In the step (3), the water extraction includes but is not limited to continuous countercurrent extraction and extraction in an extraction tank; and/or

In the step (4), the filtration is a combination of horizontal screw centrifugation, disc centrifugation and ceramic membrane clarification at the temperature of 45-65 ℃; preferably, the ceramic membrane is made of alumina or zirconia, and the pore diameter is 50-800 nm.

8. The method of claim 1, wherein in step (5), the ultrafiltration membrane decolorization, the enrichment of the first broad-spectrum adsorption resin, the ion exchange resin decolorization, the desalination and debittering of the second broad-spectrum adsorption resin, and the debittering of the phenolic acid dedicated adsorption resin are sequentially performed;

preferably, the temperature for decoloring the ultrafiltration membrane is below 40 ℃, and the molecular weight cut-off of the membrane is more than or equal to 50 KD;

preferably, the first broad spectrum adsorption resin and the second broad spectrum adsorption resin are independently selected from D101, LX-100B, LX-T28, LX-T81 and weak polarity AB-8, and the first broad spectrum adsorption resin and the second broad spectrum adsorption resin are preferably the same resin; adjusting the pH of the first broad-spectrum adsorption resin feeding liquid to about 5-6.5; the pH of the feed liquid of the second broad-spectrum adsorption resin is about 8-9.5;

preferably, the ion exchange resin is a basic anion resin, including gel type and macroporous acrylic acid weak base anion resin, acrylic acid series strong base and weak base anion resin, gel type and macroporous styrene series strong base anion resin, macroporous acrylic acid strong base anion resin, macroporous styrene series weak base anion resin;

preferably, the specification model of the special phenolic acid adsorption resin is one or any combination of a nonpolar styrene material LXD-200, a polar polyamide material LX-8, an acrylic acid material LX-17 and a styrene brominated resin LX-207.

9. The method as claimed in claim 1, wherein in the step (6), special resins for removing pesticide residues and heavy metals are used, including gel-type and macroporous acrylic resins, gel-type and macroporous styrene resins, macroporous acrylic resins, macroporous styrene resins, acrylic gel resins; before entering special resin for removing pesticide residues and heavy metals, concentrating the feed liquid by using a reverse osmosis membrane until the content of solid matters is 6-12%; and the plasticizer removing step comprises the steps of concentrating the feed liquid without pesticide residues and heavy metals to the solid content of 14-18% by using a reverse osmosis membrane, continuously stirring, heating to 60-75 ℃, adding rice bran-derived fatty acid with the volume of 0.4-1.0 time (V/V) of the concentrated feed liquid, performing heat preservation extraction, standing, cooling and collecting a water phase.

10. The method according to claim 1, wherein the concentration in step (7) is carried out at a temperature of 50 to 65 ℃ under a vacuum of-0.1 to-0.05 MPa to a concentration of 17 to 25 Baume;

the drying in the step (8) is carried out by spray drying or microwave vacuum drying, preferably spray drying, under the conditions that the air inlet temperature is 170 ℃ and 190 ℃ and the air outlet temperature is 80-90 ℃.