CN108782893B

CN108782893B - Preparation method of scorched jujube for drinking instead of tea

Info

Publication number: CN108782893B
Application number: CN201810677448.5A
Authority: CN
Inventors: 张磊
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-06-27
Filing date: 2018-06-27
Publication date: 2021-06-01
Anticipated expiration: 2038-06-27
Also published as: CN108782893A

Abstract

A preparation method of burnt wild jujube for drinking instead of tea comprises the following steps: picking wild jujube at the mature period of the wild jujube; b, adding edible soda ash into normal-temperature water to wash picked wild jujubes for the first time; c, soaking the wild jujube subjected to the first cleaning in clean water at the temperature of 70-80 ℃ for 3-4 minutes to kill enzyme: d, atomizing, spraying and inoculating saccharomycetes to the enzyme-killed wild jujube, and fermenting for 24 hours at the environmental temperature of 23-27 ℃; e, placing the fermented wild jujubes in a drying box, and carrying out drying treatment by gradually raising the temperature from room temperature to the highest temperature of 55-65 ℃ so as to enable the water content of the wild jujubes to be 10% -15%; f, washing the dried wild jujubes with clear water to finish secondary cleaning; and g, placing the wild jujubes subjected to the secondary cleaning in an oven for baking at the baking temperature of 155-165 ℃ to obtain finished product burnt wild jujubes with black and red surfaces and the water content of 7-9%. The invention has simple process steps and is easy for industrial production.

Description

Preparation method of scorched jujube for drinking instead of tea

Technical Field

The invention belongs to the technical field of processing of tea substitute drinking products, and particularly relates to a preparation method of scorched jujube serving as tea substitute drinking.

Background

The wild jujube comprises wild jujube and a large fruit type wild jujube bred by an improved variety jujube grafting technology. The wild jujube has small fruit, the average longitudinal diameter is 1.6cm, the transverse diameter is 1.45cm, the meat thickness is 2mm-4mm, and the average fruit weight is 2.17 g. The average longitudinal diameter of the bred large-fruit wild jujube is 2.52cm, the transverse diameter is 2.33cm, the thickness of the meat is 5mm-8mm, and the average fruit weight is 6.07 g. The wild jujube pulp is proved by a plurality of medical and pharmaceutical people and medical and pharmaceutical monographs, has very good food therapy value, has mild nature and sweet taste, can invigorate spleen and stimulate appetite, digest and remove food stagnation, nourish heart, calm nerves and arrest sweating after being eaten frequently, and can be used for treating neurasthenia, insomnia, dreaminess and night sweat. Because the wild jujube has small fruit, thin and loose pulp, mostly sour taste, bad taste and low yield, the practical economic value is not high. The big fruit type wild jujube bred by the improved variety jujube grafting technology, such as the crisp wild jujube bred in Shandong province, has the advantages of increased fruit type, greatly increased yield and remarkably improved taste, and has prominent practical economic value and is popularized and planted in larger and larger areas. However, fresh jujubes have high water content, high activity of various enzymes and microorganisms, are easy to decay and deteriorate, and cannot be stored for a long time, so that the further improvement of the economic value of the fresh jujubes is limited.

Disclosure of Invention

The invention aims to provide a preparation method of burnt wild jujubes for tea substitute drinking, which is characterized in that wild jujubes are processed into the burnt wild jujubes to be used as health-care products for daily brewing and drinking, and meanwhile, the wild jujubes are processed into the tea substitute drinking products which have sweet taste, rich burnt fragrance, high health-care nutritive value and convenient brewing through a proper preparation method, so that the economic value of the wild jujubes is further improved.

The technical scheme of the invention is as follows: a preparation method of burnt wild jujube for drinking instead of tea comprises the following steps:

a. picking: picking full red, full, free of plant diseases and insect pests and non-damaged wild jujube at the mature stage of the wild jujube;

b. primary cleaning: adding 5% of edible soda ash by weight into normal-temperature water, adding the wild jujube picked in the step a, stirring and cleaning for 2-3 minutes, and then rinsing twice by using clear water;

c. enzyme killing: soaking the wild jujube after the primary cleaning in clean water at 70-80 ℃ for 3-4 minutes, fully stirring, taking out the wild jujube, draining water, and naturally cooling to room temperature to obtain the wild jujube after enzyme killing treatment:

d. fermentation: putting the wild jujube after enzyme deactivation treatment in a container, atomizing, spraying and inoculating saccharomycetes, and fermenting for 24 hours at the environmental temperature of 23-27 ℃ to obtain the fermented wild jujube;

e. and (3) drying: placing the fermented wild jujube in a drying box, wherein the drying temperature is increased by 5 ℃ from room temperature every 5 minutes, the maximum drying temperature is 55-65 ℃, drying until the water content of the wild jujube pulp is 10-15%, and naturally cooling to room temperature to obtain the dried wild jujube;

f. secondary cleaning: washing the dried wild jujube with clear water;

g. baking: and (3) baking the wild jujubes subjected to secondary cleaning in an oven at the baking temperature of 155-165 ℃ until the surfaces of the wild jujubes are black and red and the water content is 7-9%, taking out the wild jujubes, naturally cooling to room temperature, packaging and sealing to obtain finished products of the burnt wild jujubes which are drunk as tea.

According to the preparation method of the scorched wild jujube for drinking instead of tea, the wild jujube picked in the step a is stored in the environment with the temperature of 5-25 ℃, so that the wild jujube is prevented from freezing due to too low temperature, and the wild jujube is prevented from rotting due to too high temperature. The enzyme killing treatment step is carried out within 36 hours, so as to avoid influencing the quality of the scorched jujube.

The preparation method of the scorched wild jujube for drinking instead of tea comprises the steps of mixing the high-activity dry yeast with clear water at 25 ℃ in a weight ratio of 1:1000, keeping the temperature for 2 hours, precipitating and removing slag to obtain yeast liquid, atomizing and spraying the yeast liquid onto the surface of the wild jujube, and uniformly mixing for inoculation.

According to the method, full red, full, disease and insect pest-free and damage-free wild jujube is selected to be picked in the mature period of the wild jujube every year, the characteristics of the wild jujube can be exerted to the maximum extent, the quality and the yield of the jujube can be seriously influenced both by early picking and late picking, the early picking not only causes thin pulp, less dry matter accumulation, low nutrient content and poor flavor, but also causes light skin color and shrivelled skin, and the late picking can cause pulp rotting and alcohol fermentation, and the quality of the scorched wild jujube is seriously influenced.

The edible soda ash is added as the cleaning agent when the raw material wild jujube is cleaned for the first time, so that the edible soda ash is low in price and good in stain and pesticide residue removing effect, and the residue of the edible soda is easily removed by clear water, so that water is saved, and the taste and the body health of the wild jujube are not influenced.

The activity of enzyme can not be inhibited quickly in the drying process of the wild jujube, a plurality of biochemical reactions are still carried out, loss of nutrient components is caused, the longer the drying time is, the greater the influence on the quality of the wild jujube is, the lower the content of the nutrient components and functional substances of the dried jujube is compared with that of the fresh jujube, the main effect is caused by the influence of the enzyme in the drying process, and the main effects are cellulase, polygalacturonase, pectin methylesterase and polyphenol oxidase generating browning, so the activity of the inhibited enzyme is beneficial to improving the nutrient content, the content of the functional substances and the comprehensive quality of the dried wild jujube, the inactivation of the enzyme is facilitated at 70-80 ℃, hot water at 70-80 ℃ is comprehensively considered and selected, the hot water is soaked for 3-4 minutes and fully stirred for enzyme killing, the operation is convenient, and the enzyme killing effect is good.

As a health product for drinking instead of tea, the protein content of the burnt zizyphus jujubes is increased, and simultaneously, a part of fructose and glucose are removed, so that the quality of the burnt zizyphus jujubes is improved, and possible adverse effects, such as adverse effects on the health of people with diabetes and obesity, are reduced. According to the method, the wild jujube is fermented by adopting the accepted healthy strain saccharomycetes without adding external additives, a part of fructose and glucose are decomposed into water and carbon dioxide to be released by utilizing the saccharomycetes under the aerobic condition, and meanwhile, beneficial substances such as protein, vitamins, amino acids and aromatic substances are added, so that the purposes of enriching the nutrition of the wild jujube, reducing the sugar content and further improving the taste are achieved.

The wild jujube drying step adopts a gradual temperature rise mode, the drying temperature is increased by 5 ℃ every 5 minutes from the basic temperature of the wild jujube, the temperature rise is too fast, carbon dioxide gas and water vapor in the wild jujube expand rapidly, the wild jujube cracks to affect the quality, the temperature rise is too slow, the sugar in the wild jujube is fermented continuously, the over fermentation is caused, and the taste of the product is affected; the highest drying temperature is set to be 55-65 ℃, so that the phenomenon that the drying time is prolonged due to too low drying temperature can be avoided, the yeast still survives to ensure that the fermentation lasts and the product quality is influenced, and the phenomenon that the nutrient substances in the wild jujube are decomposed and oxidized due to the influence of long-time high temperature and the loss of the nutrient value due to too high drying temperature can be avoided.

The temperature of the wild jujube baking step is set to be 155-165 ℃, so that the problems that the wild jujube is not easy to change color and has light burnt flavor due to too low baking temperature can be solved, and the problems that the wild jujube is too quick to change color and is not easy to control, the burnt phenomenon appears on the surface and the taste of the product is influenced due to too high baking temperature can be solved.

The invention sets the water content of the burnt date to be 7-9%, which not only can ensure that the burnt date product can be stored for a long time, but also can avoid the hardened and carbonized jujube peel of the burnt date product from influencing the brewing effect and taste.

The method for preparing the burnt wild jujube for drinking instead of tea is simple and convenient, solves some technical problems of the taste and nutrition of wild jujube, and ensures that the finished product of the burnt wild jujube has good taste, higher nutritional value and health care function of drinking instead of tea.

Detailed Description

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

The wild jujube variety adopted in the following examples is the wild jujube with the variety number of Lu S-SV-ZJS-023-2007, which is named as "crisp wild jujube", and the average longitudinal diameter of the wild jujube is 2.52cm, the transverse diameter of the wild jujube is 2.33cm, the thickness of the flesh is 5mm-8mm, and the average fruit weight is 6.07 g.

In the invention, after the enzyme killing step, the protein content and the refractive sugar of the wild jujube before the fermentation step are measured, see experiment 1.

Experiment 1:

the protein content in the wild jujube pulp is measured by adopting a Kjeldahl method, 20 g of the wild jujube without the core is taken, dried and crushed at 70 ℃, and the dried and crushed wild jujube is used as a sample for measurement.

The sugar content adopts a refractive sugar measuring method, 10 particle-size uniform wild jujube is randomly extracted as 1 sample, the wild jujube is split, the wild jujube is put into 300ml of boiling water to be boiled for 2 minutes, after the wild jujube is naturally cooled to 40 ℃, liquid is taken and dropped into a saccharimeter to be directly observed, and the saccharinity is calculated as: LB32T sugar content meter.

Kjeldahl method reagent: sulfuric acid, potassium sulfate, copper sulfate, 40% sodium hydroxide solution, 2% boric acid solution, mixed indicator, anhydrous sodium carbonate and 0.05mol/L hydrochloric acid standard solution, wherein the used water is distilled water of ammonia and carbon dioxide. The used instruments are: KDY-9830 Kjeldahl nitrogen determination instrument, KXL-1010 temperature control digestion furnace, AL104 electronic balance, digestion tube and volumetric flask.

6 samples were randomly taken for measurement, and the results are shown in statistical Table 1.

Statistics Table 1

Sample number	1	2	3	4	5	6
							Protein content%	2.1	2.1	2.2	2.1	2.2	2.2
Refractive sugar%	3.9	4.1	4.0	3.9	4.1	4.0

The above measurement results were used as reference values for reference in the subsequent experiment 2.

Experiment 2:

in the wild jujube fermentation step, the protein content and the refractive sugar content of four time points of fermentation for 8 hours, 16 hours, 24 hours and 32 hours are measured. The methods, procedures, reagents, instruments and experiment 1 were identical.

In the wild jujube fermentation step, 6 samples are randomly taken at four time points of 8 hours, 16 hours, 24 hours and 32 hours of fermentation respectively for measurement, and the results are shown in the statistical table 2.

Statistics Table 2

Sample number	1	2	3	4	5	6
							Protein content at 8 hours%	2.4	2.4	2.4	2.4	2.5	2.5
16 hours protein content%	2.7	2.7	2.6	2.6	2.8	2.7
							Protein content at 24 hours%	3.0	3.1	3.1	3.0	3.0	3.0
32 hours protein content%	3.7	3.7	3.8	3.9	3.7	3.6
							8 hours refractive sugar%	3.5	3.3	3.3	3.4	3.4	3.3
Refractive sugar content in 16 hours%	2.8	2.9	2.7	2.7	2.8	2.8
							Refractive sugar content in 24 hours%	2.0	2.2	2.2	2.1	2.0	2.1
Refractive sugar content in 32 hours%	1.0	0.9	0.8	0.9	0.9	0.9

The statistics of the values in the table 2 in the experiment 2 and the statistics of the values in the table 1 in the comparison experiment 1 show that the protein content in the zizyphus jujuba is obviously increased along with the time in the fermentation step, which indicates that the number of the yeasts is obviously increased in the fermentation process, and meanwhile, the contents of the amino acid, the vitamin and the aromatic substance are correspondingly increased, the increase of the number of the yeasts improves the nutritional value of the zizyphus jujuba, and the increase of the number of the yeasts enables the contents of fructose and glucose in the zizyphus juba to be correspondingly reduced.

After 32 hours of fermentation, protein still increases, refractive sugar is reduced to about 1.0%, bitter and astringent taste and sour taste appear simultaneously, wild jujube peel appears brown, and the taste is reduced, and compared with the growth of mixed bacteria and over fermentation, the effect is best after 24 hours of fermentation.

Example 1

A preparation method of burnt wild jujube for drinking instead of tea comprises the following steps:

a. picking: the mature period of the wild jujube is from 9 months 5 days to 9 months 20 days every year, and the wild jujube with red, full, no plant diseases and insect pests and no damage fruits is selected to be picked manually in the mature period of the wild jujube. The manual picking is carried out to ensure the integrity of the peel and prevent the peel from cracking in the subsequent processing to influence the appearance integrity and the quality of the burnt zizyphus jujubes. The storage environment temperature and the transportation environment temperature of the picked wild jujubes are between 5 and 25 ℃, and the picked wild jujubes are subjected to enzyme killing treatment within 36 hours.

b. Primary cleaning: and (b) adding 5% of edible soda ash by weight into normal-temperature water, adding the wild jujube picked in the step a, manually stirring and cleaning for 3 minutes, then rinsing twice with clear water, taking out the wild jujube, placing on a stainless steel sieve, and draining the water on the surface of the wild jujube.

c. Enzyme killing: and c, soaking the wild jujubes subjected to the primary cleaning in the step b in clean water at 70 ℃ for 4 minutes, simultaneously carrying out manual stirring, taking out the wild jujubes, placing the wild jujubes on a stainless steel sieve, draining the water on the surface of the wild jujubes, and naturally cooling the wild jujubes to room temperature to obtain the wild jujubes subjected to enzyme killing treatment.

d. Fermentation: putting the wild jujube subjected to enzyme killing treatment in a stainless steel container, spraying and inoculating saccharomycetes in an atomizing manner, and fermenting for 24 hours at the environmental temperature of 23 ℃ to obtain the fermented wild jujube; the yeast is high-activity dry yeast sold in the market, the high-activity dry yeast and clean water at 25 ℃ are manually stirred and mixed according to the weight ratio of 1:1000, the temperature is kept for 2 hours, then the yeast liquid is precipitated and removed, yeast liquid is obtained, an electric sprayer is used for uniformly spraying the yeast liquid on the surface of the wild jujube, the yeast liquid is matched and stirred for inoculation, the sprayed yeast liquid is suitable for forming a thin uniform liquid film on the surface of the wild jujube, no accumulated liquid is left at the bottom of the container, the container is covered, the yeast liquid is turned over once every 4 hours to increase the oxygen content between the wild jujubes, and the fermentation is continued for 24 hours.

e. And (3) drying: and (3) placing the fermented wild jujube in a belt type dryer, raising the drying temperature to 5 ℃ every 5 minutes from the room temperature, and naturally cooling the wild jujube until the water content of the wild jujube pulp is 15% to the room temperature to obtain the dried wild jujube.

f. Secondary cleaning: and (3) putting the dried wild jujube into a container with a sieve bottom, spraying clear water at high pressure for washing to remove dust stained with the wild jujube in the fermentation and drying processes, and then quickly draining the water on the surface of the wild jujube by using a vibration draining machine.

g. Baking: and (3) placing the wild jujube subjected to secondary cleaning in a hot air circulation drying box for baking, wherein a tray of the baking box adopts a 304 stainless steel net, the mesh size is 5mm multiplied by 5mm, only one layer of the wild jujube is spread, heating is carried out at 155 ℃ until the surface of the wild jujube is black-red, the black-red color is judged to be similar to color card (CMYK:0, 90, 80, 45), the wild jujube is baked until the water content of the pulp of the wild jujube is 9%, then the wild jujube is taken out, naturally cooled to room temperature, packaged and sealed, and the finished product of the wild jujube for drinking instead of tea is obtained.

The burnt and sour jujube prepared by the method has black red surface, uniform color, strong jujube fragrance and burnt fragrance, no peculiar smell and moderate toughness, 10 granules are selected optionally, the burnt and sour jujube is put into a cup with a cover, the cup is brewed by 300ml of boiling water, the cup is covered and naturally cooled to 40 ℃, the liquor color is clear and bright, the jujube is brownish red, the jujube is burnt and fragrant, sweet and thick, and the taste is pure and thick.

Example 2

a. picking: the mature period of the wild jujube is from 9 months 5 days to 9 months 20 days every year, and the wild jujube with red, full, no plant diseases and insect pests and no damage fruits is selected to be picked manually in the mature period of the wild jujube. The storage environment temperature and the transportation environment temperature of the picked wild jujube are 5-25 ℃. The picked wild jujube is subjected to enzyme killing treatment within 36 hours.

b. Primary cleaning: and (b) adding 5% of edible soda ash by weight into normal-temperature water, putting the wild jujube picked in the step a into a machine, stirring and cleaning for 2 minutes, then rinsing twice with clear water, taking out the wild jujube, placing the wild jujube on a stainless steel sieve, and draining the water on the surface of the wild jujube.

c. Enzyme killing: and c, soaking the wild jujube subjected to the primary cleaning in the step b in purified water at 75 ℃ for 3.5 minutes, simultaneously mechanically stirring, taking out the wild jujube, placing the wild jujube on a stainless steel sieve, draining the water on the surface of the wild jujube, and naturally cooling to room temperature to obtain the wild jujube subjected to enzyme killing treatment.

d. Fermentation: putting the wild jujube subjected to enzyme killing treatment in a stainless steel container, spraying and inoculating saccharomycetes in an atomizing manner, and fermenting for 24 hours at the ambient temperature of 25 ℃ to obtain the fermented wild jujube; the yeast is high-activity dry yeast sold in the market, the high-activity dry yeast and clean water at 25 ℃ are manually stirred and mixed according to the weight ratio of 1:1000, the temperature is kept for 2 hours, then the yeast liquid is precipitated and removed, yeast liquid is obtained, an electric sprayer is used for uniformly spraying the yeast liquid on the surface of the wild jujube, the yeast liquid is matched and stirred for inoculation, the sprayed yeast liquid is suitable for forming a thin uniform liquid film on the surface of the wild jujube, no accumulated liquid is obtained at the bottom of the container, the container is covered, the yeast liquid is turned over once every 3.5 hours, so that the oxygen content between the wild jujubes is increased, and the fermentation is continued for 24.

e. And (3) drying: and (3) placing the fermented wild jujube in a belt type dryer, raising the drying temperature to 5 ℃ every 5 minutes from the room temperature, and naturally cooling to the room temperature until the water content of the wild jujube pulp is 13% to obtain the dried wild jujube, wherein the maximum drying temperature is 60 ℃.

g. Baking: and (3) placing the wild jujube subjected to secondary cleaning in a hot air circulation drying box for baking, wherein a tray of the baking box adopts a 304 stainless steel net, the mesh size is 5mm multiplied by 5mm, only one layer of the wild jujube is spread, heating is carried out at 160 ℃ until the surface of the wild jujube is black and red, the black and red are judged to be similar to color cards (CMYK:0, 90, 80 and 45), the wild jujube pulp is taken out after the water content is 8 percent, naturally cooling to room temperature, packaging and sealing to obtain the finished product of the wild jujube for drinking instead of tea.

Example 3

c. Enzyme killing: and c, soaking the wild jujube subjected to the primary cleaning in the step b in purified water at the temperature of 80 ℃ for 3 minutes, simultaneously mechanically stirring, taking out the wild jujube, placing the wild jujube on a stainless steel sieve, draining the water on the surface of the wild jujube, and naturally cooling to room temperature to obtain the wild jujube subjected to enzyme killing treatment.

d. Fermentation: putting the wild jujube subjected to enzyme killing treatment in a stainless steel container, spraying and inoculating saccharomycetes in an atomizing manner, and fermenting for 24 hours at the environmental temperature of 27 ℃ to obtain the fermented wild jujube; the yeast is high-activity dry yeast sold in the market, the high-activity dry yeast and clean water at 25 ℃ are manually stirred and mixed according to the weight ratio of 1:1000, the temperature is kept for 2 hours, then the yeast liquid is precipitated and removed, yeast liquid is obtained, an electric sprayer is used for uniformly spraying the yeast liquid on the surface of the wild jujube, the yeast liquid is matched and stirred for inoculation, the sprayed yeast liquid is suitable for forming a thin uniform liquid film on the surface of the wild jujube, no accumulated liquid is left at the bottom of the container, the container is covered, the yeast liquid is turned over once every 3 hours so as to increase the oxygen content between the wild jujubes, and the fermentation is continued for 24 hours.

e. And (3) drying: and (3) placing the fermented wild jujube in a belt type dryer, raising the drying temperature to 5 ℃ every 5 minutes from the room temperature, and naturally cooling the wild jujube to the room temperature until the water content of the wild jujube pulp is 10% to obtain the dried wild jujube.

g. Baking: and (3) placing the wild jujube subjected to secondary cleaning in a hot air circulation drying box for baking, wherein a tray of the baking box adopts a 304 stainless steel net, the mesh size is 5mm multiplied by 5mm, only one layer of the wild jujube is spread, heating is carried out at 165 ℃ until the surface of the wild jujube is black and red, the black and red are judged to be similar to color cards (CMYK:0, 90, 80 and 45), the wild jujube pulp is taken out after the water content is 7%, naturally cooling to room temperature, packaging and sealing to obtain the finished product of the wild jujube for drinking instead of tea.

The preparation method of the scorched wild jujube instead of tea beverage is also suitable for wild jujubes and other varieties of large-fruit wild jujubes.

The preparation method of the burnt wild jujube drinking instead of tea has simple process steps, convenient operation, low cost and easy industrial production.

Claims

1. A preparation method of burnt wild jujube for drinking instead of tea is characterized by comprising the following steps:

e. and (3) drying: placing the fermented wild jujube in a drying box, starting from room temperature, increasing the drying temperature by 5 ℃ every 5 minutes, drying at the maximum drying temperature of 55-65 ℃ until the water content of the wild jujube pulp is 10% -15%, and naturally cooling to room temperature to obtain the dried wild jujube;

f. secondary cleaning: washing the dried wild jujube with clear water;

2. The method for preparing the burnt ziziphus jujubes with tea substitute according to claim 1, wherein the method comprises the following steps: the wild jujube picked in the step a is stored in an environment with the temperature of 5-25 ℃, and enters the enzyme killing treatment step within 36 hours.

3. The method for preparing the burnt ziziphus jujubes with tea substitute according to claim 1, wherein the method comprises the following steps: the yeast is high-activity dry yeast which is mixed with clear water at 25 ℃ in a weight ratio of 1:1000, the temperature is kept for 2 hours, then the yeast liquid is obtained by precipitation and slag removal, the yeast liquid is atomized and sprayed onto the surface of the wild jujube, and the mixture is uniformly mixed for inoculation.