CN107455482B - Method for self-assembling multilayer film on surface of milk curd - Google Patents
Method for self-assembling multilayer film on surface of milk curd Download PDFInfo
- Publication number
- CN107455482B CN107455482B CN201710690667.2A CN201710690667A CN107455482B CN 107455482 B CN107455482 B CN 107455482B CN 201710690667 A CN201710690667 A CN 201710690667A CN 107455482 B CN107455482 B CN 107455482B
- Authority
- CN
- China
- Prior art keywords
- milk
- chitosan
- ultrapure water
- curd
- self
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23C—DAIRY PRODUCTS, e.g. MILK, BUTTER OR CHEESE; MILK OR CHEESE SUBSTITUTES; MAKING THEREOF
- A23C19/00—Cheese; Cheese preparations; Making thereof
- A23C19/097—Preservation
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Polymers & Plastics (AREA)
- Dairy Products (AREA)
- Jellies, Jams, And Syrups (AREA)
Abstract
The invention relates to a method for self-assembling a multilayer film on the surface of milk curd, which comprises the steps of preparing a linseed glue aqueous solution, preparing a chitosan aqueous solution, pretreating milk curd, self-assembling in situ and the like. In the self-assembly milk bean curd, the thin film layer is highly ordered and directional, the film forming is stable, the shape of the milk bean curd is not limited, the preparation method is simple, expensive instruments and equipment are not needed, and the self-assembly milk bean curd has the specificity of self-assembly substances. The self-assembled multilayer film has certain bionic effect because the structure of the self-assembled film is similar to that of a cell membrane.
Description
Technical Field
The invention belongs to the field of food preservation. More particularly, the invention relates to a method for self-assembling a multilayer film on the surface of milk curd.
Background
The cheese can be the essence of milk, has delicious taste, has the protein content of more than 70.84 percent, is rich in amino acid and other trace elements beneficial to the body, and is one of the good products with rich nutrition and capability of improving the immunity. However, cheese is difficult to preserve in storage, has the phenomena of mould formation, fat deposition and short shelf life, while cheese packaging in the market is mainly vacuum packaging and air-filled packaging, for example, suzhou tianjia new materials limited CN 101306744a discloses a heat-shrinkable bag for cheese packaging; although the self-assembled polymer film for food packaging of the Dow globe technology company of America can well solve the problems, the self-assembled polymer film has the defects that the shrink packaging is easy to deform, the attractiveness and appetite are influenced, the gas-filled packaging process is complicated, and particularly, the placing of an oxygen scavenger can cause potential food safety hazards. The shrink packaging and the gas packaging are also called as common packaging, the common packaged milk tofu causes great damage to the eating quality such as the taste and the flavor of the product due to the secondary heat sterilization process, the fragrance is obviously weakened, and the peculiar smell of the product is more likely to be generated due to over sterilization. At present, the global attention on plastic packaging waste pollution is high, edible packaging films inevitably become mainstream, and functional films with various efficacies can be prepared by using proper bacteriostatic agents in edible film formulas, so that the mainstream packaging is realized, wherein a self-assembly technology is the best technology.
In view of the technical defects of the prior art, the present inventors have completed the present invention through a large number of experiments and analyses based on the summary of the prior art.
Disclosure of Invention
Technical problem to be solved
The invention aims to provide a method for self-assembling a multilayer film on the surface of a milk curd.
Technical scheme
The invention is realized by the following technical scheme.
The invention relates to a method for self-assembling a multilayer film on the surface of a milk curd.
The method comprises the following steps:
A. preparation of aqueous solution of flaxseed gum
The ratio of the linseed glue in grams to the ultrapure water in milliliters is 0.1-10: 100-500, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 1-10 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid and ultrapure water in milliliters is 0.1-10: 1-30: 100-500, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 2-10 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in a phosphate buffer solution with the pH = 2-4 to ensure that the surfaces of the milk bean curd blocks are positively charged, or soaking the milk bean curd blocks in a phosphate buffer solution with the pH = 6-8 to ensure that the surfaces of the milk bean curd blocks are negatively charged;
D. in situ self assembly
B, soaking the milk tofu with the positively charged surface in the linseed gum solution prepared in the step A, standing, keeping the adsorption balance of the linseed gum, adsorbing the linseed gum on the surface of the milk tofu to be negatively charged, washing with ultrapure water, removing the non-specifically adsorbed linseed gum, and airing; then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, balancing the adsorption of chitosan, adsorbing chitosan on the surface of the linseed gum adsorbed milk tofu to be electropositive, then washing with ultrapure water, removing the non-specifically adsorbed chitosan, and drying in the air; this is repeated in such a manner that a plurality of films are self-assembled on the surface of the dried milk cake.
According to a preferred embodiment of the invention, in the step A, the ratio of the linseed glue to the ultrapure water is 1-8: 180-400.
According to another preferred embodiment of the present invention, in the step B, the ratio of chitosan, citric acid and ultrapure water is 1 to 8: 8-22: 180 to 420.
According to another preferred embodiment of the present invention, in step C, the phosphate buffer with pH = 2-4 and the phosphate buffer with pH = 6-8 are prepared as follows: dissolving 20-50 g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and fixing the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; and (3) preparing a phosphate buffer solution with the pH = 2-4 and a phosphate buffer solution with the pH = 6-8 by using a disodium hydrogen phosphate solution, a sodium dihydrogen phosphate solution and citric acid, and performing ultraviolet sterilization on the phosphate buffer solutions for 5-20 min.
According to another preferred embodiment of the present invention, in step D, the milk-like curd is left in the linseed glue solution for adsorption equilibrium for 8-12 seconds.
According to another preferred embodiment of the present invention, in the step D, the milk curd is left to stand in the chitosan water solution for adsorption equilibrium for 8 to 12 seconds.
According to another preferred embodiment of the present invention, in the step D, the ratio of the milk curd in grams to the ultrapure water in milliliters is 1:10 to 20.
According to another preferred embodiment of the present invention, in the step D, the washed milk curd is dried on a clean bench for 0.8 to 1.4 min.
According to another preferred embodiment of the present invention, in step D, the self-assembly of the multi-layered thin film is performed on the surface of the dried milk curd in an assembly order opposite to the assembly order of the above step D.
According to another preferred embodiment of the present invention, in the step D, the self-assembly is repeated 5 to 10 times on the surface of the milk curd in the same manner.
The present invention will be described in more detail below.
The invention relates to a method for self-assembling a multilayer film on the surface of a milk curd.
Flaxseed gum is an anionic polysaccharide and a good emulsifier, and studies show that the emulsifier plays a role in balancing and stabilizing by reducing the tension between water/oil interfaces. When the protein, the emulsifier and the milk fat meet, the milk fat and the protein can be replaced by the emulsifier molecules, which can control the milk protein competitively adsorbed on the surface of the milk curd, thereby controlling the fat precipitation.
Chitosan is a cationic polysaccharide, has broad-spectrum antibacterial property, and has certain effect on fungi, bacteria and viruses.
Because the chitosan and the linseed glue have the characteristics, the chitosan and the linseed glue are alternately assembled on the surface of the cheese by using an electrostatic self-assembly technology, so that the functions of inhibiting bacteria and preventing fat from being separated out are achieved.
The method comprises the following steps:
A. preparation of aqueous solution of flaxseed gum
The ratio of the linseed glue in grams to the ultrapure water in milliliters is 0.1-10: 100-500, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 1-10 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
in the invention, when the using amount of the ultrapure water is 100-500, if the using amount of the linseed glue is less than 0.1, the self-assembly is not uniform, and even the cheese part is exposed; if the dosage of the linseed glue is more than 10, the phenomenon of over-thickness of a self-assembled layer can occur; therefore, the amount of the linseed gum is 0.1-10, preferably 1-8, and more preferably 2-6.
The linseed gum used in the present invention is a product currently sold in the market, for example, linseed gum sold by Biotech limited of Xinjiang Lishi.
In the invention, the ratio of the linseed glue to the ultrapure water is preferably 1-8: 180-400.
B. Preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid and ultrapure water in milliliters is 0.1-10: 1-30: 100-500, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 2-10 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
the main purpose of using citric acid in the preparation of the aqueous chitosan solution is to promote the dissolution of chitosan and to make it electropositive, and the citric acid used in the present invention is currently marketed, for example, by Feng ship chemical technology, Tianjin. The chitosan used in the present invention is a product currently on the market, such as chitosan sold by Shandong tobacco science and technology (degree of deacetylation 97.7%).
In the invention, when the using amount of the ultrapure water is 100-500, if the using amount of the chitosan is less than 0.1, self-assembly is not uniform, and even the cheese part is exposed; if the dosage of the chitosan is more than 10, the phenomenon of over-thickness of the self-assembled layer can occur; therefore, the amount of chitosan is 0.1 to 10, preferably 1 to 8, and more preferably 2 to 6.
In the invention, when the using amount of the ultrapure water is 100-500, if the using amount of the citric acid is less than 1, the chitosan is not dissolved, and electropositive chitosan cannot be formed; if the dosage of the citric acid is more than 30, the chitosan can be degraded; therefore, the amount of citric acid is 1 to 30, preferably 8 to 22, and more preferably 12 to 18.
In the present invention, the ratio of chitosan, citric acid and ultrapure water is preferably 1 to 8: 8-22: 180 to 420.
C. Pretreatment of milk curd
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in a phosphate buffer solution with the pH = 2-4 to ensure that the surfaces of the milk bean curd blocks are positively charged, or soaking the milk bean curd blocks in a phosphate buffer solution with the pH = 6-8 to ensure that the surfaces of the milk bean curd blocks are negatively charged;
the milk bean curd used in the invention is prepared by adopting the conventional milk bean curd preparation methodTo or from the market. The size of the milk curd pieces is not particularly critical and is usually 2X 1cm3。
According to the invention, the preparation method of the phosphate buffer solution with the pH = 2-4 and the phosphate buffer solution with the pH = 6-8 comprises the following steps: dissolving 20-50 g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and fixing the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; and (3) preparing a phosphate buffer solution with the pH = 2-4 and a phosphate buffer solution with the pH = 6-8 by using a disodium hydrogen phosphate solution, a sodium dihydrogen phosphate solution and citric acid, and performing ultraviolet sterilization on the phosphate buffer solutions for 5-20 min.
The disodium hydrogen phosphate solution and the sodium dihydrogen phosphate used in the invention are products produced by the maoyang chemical reagent factory in Tianjin.
D. In situ self assembly
B, soaking the milk tofu with the positively charged surface in the linseed gum solution prepared in the step A, standing, keeping the adsorption balance of the linseed gum, adsorbing the linseed gum on the surface of the milk tofu to be negatively charged, washing with ultrapure water, removing the non-specifically adsorbed linseed gum, and airing; then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, balancing the adsorption of chitosan, adsorbing chitosan on the surface of the linseed gum adsorbed milk tofu to be electropositive, then washing with ultrapure water, removing the non-specifically adsorbed chitosan, and drying in the air; this is repeated in such a manner that a plurality of films are self-assembled on the surface of the dried milk cake.
The main component of the milk bean curd is casein, and the rice protein has a zate potential of-23 at pH =7, a zate potential of +20 at pH =4, a potential of +69.7 of chitosan under acidic conditions, and a potential of-34 of flaxseed gum. The substances have potential difference, so that the self-assembly condition is provided.
The cheese self-assembly film is based on the alternating formation of ordered chitosan and linseed gum multilayer films on the surface of cheese. They have bacteriostatic and lipolysis-controlling functions.
According to the invention, the method for judging the adsorption balance of the milk curd in the linseed gum aqueous solution is an optimal scheme obtained by electron microscope observation; and standing the milk bean curd in the linseed glue solution for adsorption balance for 8-12 seconds. If this adsorption equilibrium time is shorter than 8 seconds, self-assembly is incomplete; if this adsorption equilibration time is longer than 12 seconds, it results in an excessively thick self-assembled layer; therefore, it is preferable that the adsorption equilibrium time is 8 to 12 seconds.
In step D of the present invention, the ratio of the milk curd in grams to the ultrapure water in milliliters at the time of the ultrapure water rinsing is 1:10 to 20.
During rinsing with ultrapure water, it was judged by visual observation that nonspecifically adsorbed flaxseed gum was substantially removed.
The milk tofu washed with ultrapure water was placed on a clean bench sold under the trade name stainless steel double-person vertical flow clean bench by Suzhou Mancheng air cleaning facility Limited to be air-dried for 0.8 to 1.4 min.
According to the invention, the method for judging the adsorption balance of the milk bean curd adsorbing the linseed glue in the chitosan aqueous solution is to use an electron microscope observation method; standing the milk curd adsorbing the flaxseed gum in a chitosan water solution, and adsorbing and balancing for 8-12 seconds. If this adsorption equilibrium time is shorter than 8 seconds, self-assembly is incomplete; if this adsorption equilibrium time is longer than 12 seconds, the self-assembled layer is too thick; therefore, such an adsorption equilibrium time of 8 to 12 seconds is feasible.
After adsorbing chitosan, the ratio of milk curd in grams to ultrapure water in milliliters at the time of rinsing with ultrapure water was 1:10 to 20. When rinsing with ultrapure water, it was judged by visual observation that the non-specifically adsorbed chitosan had been substantially removed. The milk tofu washed with ultrapure water was placed on a clean bench sold under the trade name stainless steel double-person vertical flow clean bench by Suzhou Mancheng air cleaning facility Limited to be air-dried for 0.8 to 1.4 min.
Preferably, the self-assembly is repeated on the surface of the milk curd for 5-10 times in the same manner in the step D, so that 5-10 layers of films are arranged on the surface of the milk curd, each film layer is composed of a flaxseed glue layer and a chitosan layer, and the flaxseed glue layers and the chitosan layers are alternately distributed on the whole.
According to the invention, the self-assembly of the multilayer film on the surface of the milk curd can be carried out according to the reverse assembly sequence of the step D, namely, the milk curd with negative surface is firstly soaked in the chitosan aqueous solution prepared in the step B and then soaked in the linseed gum solution prepared in the step A, and other steps and relevant parameters are not changed.
The milk tofu with the self-assembled multilayer film on the surface is stored in a constant temperature and humidity box under the conditions that the temperature is 15-30 ℃ and the relative humidity is 70-83%.
Self-assembled tofu samples were sectioned using a cryomicrotome at a temperature of-30 ℃. A sliced section was attached to the stage of SEM, frozen in a freeze-dryer for 4 hours, dried for 11 hours, sprayed with gold, and the section of the dried milk was observed under SEM (Shimadni S-530, Japan), and the results of the observation are shown in FIG. 1.
The surface appearance of five groups of different self-assembled layer milk bean curd is observed by an electron microscope and is shown in figure 1. FIG. 1a shows a blank group, wherein the surface of the milk curd is porous and the surface of the milk curd is uneven; fig. 1 shows that as the number of coating layers increases, the surface porous structure slowly disappears, the surface of the milk curd is gradually covered by the layer self-assembly film, when the milk curd is assembled into 10 double layers, the surface of the milk curd is completely covered (fig. 1c and 1 e), and the original uneven surface is gradually even and flat. The surface of the milk curd is smooth, which indicates that the coating effect of the self-assembled film on the surface of the milk curd is better. FIGS. 1f, 1g and 1h are sectional views of the self-assembled milk curd of the present invention, from which it can be seen that the self-assembled film is assembled on the surface of the milk curd, and the thickness of the self-assembled film is 5-6 μm according to SEM (drawing h).
The test of the effect of the self-assembled film on the performance of the milk curd is described as follows:
fat separation
Placing the self-assembled milk bean curd sample in a culture dish paved with filter paper, placing the culture dish in a constant temperature box with the temperature of 13 ℃ for 20min, then placing the culture dish in an oven, heating the culture dish to 80 ℃, taking out the culture dish after 40 min, then placing the culture dish in the constant temperature box with the temperature of 13 ℃ for 30min, allowing the temperature of the culture dish to be stable, then measuring the oil ring diffusion diameter of the sample by using a vernier caliper, measuring the oil ring diffusion diameter to be accurate to 0.1 mm, measuring for 6 times, taking the mean value of the oil ring diffusion diameter, and calculating the oil precipitation diameter of the self-assembled milk bean.
Fig. 2 is a graph of the fat deposition as a function of storage time for the self-assembled milk curd of the present invention wherein (a) a buffer solution of pH =3 is used; (b) a buffer solution of pH =7 was used. The fat deposition increases with longer storage time for the blank, 5, 5.5 bilayers, and the fat deposition increases with longer storage time for 10 and 10.5 bilayers, but overall, the fat deposition is much higher for the blank than when buffer solutions are used.
II, pH value
According to the ratio of milk bean curd in grams to distilled water in milliliters of 1:10, mixing and grinding the self-assembly milk bean curd with distilled water, and measuring the pH value of the mixture. The results are shown in FIG. 3. The general trend of the pH of the milk curds in the storage process is that the pH of the milk curds is firstly reduced and then increased, the pH reaches the lowest point on the 3 rd or the 4 th day respectively, the difference between the samples in the groups is not obvious (P is more than 0.05) in the descending trend of the first three days, the samples in the groups slowly increase, the difference between the test group and the blank group is obvious (P is less than 0.05), and the pH of the self-assembled milk curds is lower than that of the blank group because the chitosan and linseed gum self-assembled film has inhibition effect on yeast and mould and has certain influence on ammonium ions.
Third, hardness and chewiness
Measurement parameters are as follows: an instrument sold under the trade name texture instrument by Stable Micro System company, UK, model measure force in compress, TPA; the descending speed of the probe is 1mm s before measurement-1(ii) a Test rate of 1mm s-1(ii) a The return speed of the probe after the test is 1mm s-1(ii) a The deformation amount is 30%; 5g of trigger force; probe type P100. Each group was assayed in duplicate 6 times. The results of the measurements are shown in FIGS. 4 and 5.
The change rule of the hardness and the chewiness are the same, and as is obvious from the attached figures 4 and 5, the hardness of the blank group is gradually reduced along with the prolonging of the storage time, because the internal fat of the milk tofu is slowly separated out in the storage process, and the fat is aggregated to form a fat groove, so that the protein network structure of the milk tofu is damaged, the action of water and fat is enhanced, and the hardness and the chewiness of the product are reduced. The hardness and chewiness of the self-assembled milk tofu prepared by using the buffer solution are increased along with the increase of the number of self-assembled layers, and the difference between the layers is not large (P >0.05) compared with that between the layers (5 and 5.5, 10 and 10.5), so that the outmost layer is linseed gum or chitosan. In conclusion, the blank group has reduced hardness and chewiness, and the original hardness and chewiness of the milk curd are well ensured by the double layers of 5 and 5.5. 10 and 10.5 bilayers increase the hardness and chewiness of the milk curd.
Fourth, color difference
The color of the milk curd is a very important index for sensory evaluation of the milk curd. The color characteristics of the milk curd are represented by L (lightness difference) and b (partial yellowness). The measurement was carried out in a conventional manner using an apparatus sold under the trade name colorimeter by Konika Mentada, Japan. The measurement was repeated 3 times, and the average value was taken. The results are plotted in FIGS. 6a, b, c, d. It can be seen from the figure that L values of 9 tested milk curds are gradually decreased with the increase of storage time, because the milk curds are continuously hydrolyzed to produce small molecular peptide fragments and amino acids due to the interaction of microorganisms and enzymes during the storage process, meanwhile, the fat is hydrolyzed to free fatty acid, and the change of the material components directly influences the reflection of light, so the L values are continuously decreased. As the number of layers (0, 5, 10) increases, the value of L decreases, with no apparent difference between the layers (P > 0.05).
The b value of the blank sample increased and then decreased with the increase of the storage time, because the protein in the milk curd could not adsorb the free fat in the first three days, and the b value of the fat deposition increased. After day 3 the mould content on the surface of the milk curd increased, resulting in a decrease of the b-value of the milk curd. While the remaining 8 test groups decreased and then remained slowly ascending with increasing days of storage.
The values of the buffer solution adjusting layer with pH =3 decreased in the first 3 days and the buffer solution with pH =7 decreased in the first 2 days, because the emulsifying property of the linseed gum was exerted after the self-assembly, and a large amount of free fatty acid was adsorbed on the surface, so that the milk curd was whitened. With the increase of the storage time, the activity of the flaxseed gum is reduced or the adsorption of the flaxseed gum is balanced, so that the residual fat is separated out, and the b value at the later stage is slowly increased. As the number of layers increases, the value of b gradually decreases. pH =7 buffer solution adjusting layer compared to pH =3 buffer solution adjusting layer, b-value of pH =7 buffer solution adjusting layer (compared between the same layers) was lower than b-value of pH =3 buffer solution adjusting layer because the mold content on the surface of the milk curd regulated by pH =7 buffer solution was small. In a word, self-assembly has a great influence on the color difference of the milk curd.
The effect of the self-assembled film on the microorganisms of the milk curd is described below.
Determination of the total number of colonies: detecting the total number of all groups of bacterial colonies by adopting a national standard GB/T4789.2-2010;
the coliform group bacteria determination method is as follows:
inoculating coliform bacteria; activating Escherichia coli on a slant at 37 ℃, culturing for 48 h by using a 37 ℃ incubator, obtaining a loop on the slant by using an inoculating loop after activation, placing the loop in 10 mL of sterile physiological saline, taking 1mL of 1:10 sample homogenate by using a 1mL sterile pipette or a micropipette, slowly adding 9 mL of phosphate buffer solution or physiological saline into a sterile test tube along the tube wall, diluting to a specific concentration according to the method, namely inoculating the bacterial solution, and inoculating 200 mu L of the inoculum on the surface of each milk bean curd. In order to evenly distribute the inoculation liquid on the surface of the milk curd, five evenly distributed points are selected on the surface of the milk curd, and 40 mu L of inoculation liquid is injected into each point by a liquid transfer machine. All the processes are carried out in the biological safety cabinet. The enumeration was carried out according to the MPN enumeration method of Escherichia coli in GB 4789.3-2010.
Determination of staphylococcus aureus: staphylococcus aureus inoculation was the same as that of Escherichia coli, determined according to GB 4789.10-2010.
Determination of total number of mold and yeast: the total number of moulds and yeasts was determined according to GB 4789.15-2010.
The microorganism mainly detects the total number of bacterial colonies and exogenous microorganisms, wherein the exogenous microorganisms comprise gram-negative bacteria, large intestine, gram-positive bacteria, staphylococcus aureus and mould microzyme which has the greatest influence on the milk curd. As can be seen from fig. 8, 9, 10 and 11, the number of colonies of each index is reduced along with the increase of the number of self-assembled layers, and the chitosan milk tofu as the outermost layer has a significantly better bacteriostatic effect than the linseed glue layer; for three indexes of staphylococcus aureus, coliform groups and total number of bacterial colonies, when the surface of the milk curd is electropositive, the number of the bacterial colonies is less than electronegativity, and 10 double-layer antibacterial effects of the three indexes at pH =3 are optimal; the mould yeast has the best bacteriostatic effect when the mould yeast is in 10.5 double layers with pH =7 and is electronegative, and the storage period is prolonged by 300% compared with that of a blank group, so that the bacteriostatic effect of the self-assembled film is proved to be good.
Advantageous effects
The invention has the beneficial effects that:
(1) high orderliness and directionality, stable film forming, no limitation of the shape of the milk curd, simple preparation method and no need of expensive instruments and equipment.
(2) Surfaces with specific interactions can be obtained by precise chemical control.
(3) The self-assembly material specificity on the surface of the milk curd is obtained, so that the milk curd has a protection effect and a long shelf life.
(4) The self-assembled membrane structure is similar to a cell membrane, so that the membrane has a certain bionic effect.
[ description of the drawings ]
FIG. 1 is a surface and cross-sectional profile of a self-assembled tofu in accordance with the present invention;
in the figure:
a-blank, b-pH =3, 5 layers, c-pH =3, 10 layers, d-pH =7, 5 layers, e-pH =7, 10 layers; f-blank group cross section appearance, g-self-assembly milk bean curd cross section appearance, and h-SEM observed milk bean curd cross section.
FIG. 2 is a graph showing the effect of the self-assembled film of the present invention on the total number of colonies of a milk curd;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 3 is a graph showing the effect of the self-assembled film of the present invention on the pH of a fermented milk curd.
In the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 4 is a graph showing the change in hardness of the self-assembled milk curd of the present invention during storage;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 5 is a graph showing the variation of chewiness of the self-assembled milk curd of the present invention during storage;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 6 is a graph showing the effect of the self-assembled film of the present invention on color difference of milk curd;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7; c-buffer solution of pH = 3; buffer solution of d-pH =7
FIG. 7 is a sensory panel of the self-assembled dried milk curd of the present invention;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 8 is the effect of the self-assembling film of the present invention on the total number of colonies of a milk curd;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 9 is the effect of the self-assembled film of the present invention on the total number of Escherichia coli in milk curd
In the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 10 is a graph showing the effect of the self-assembled film of the present invention on the total number of Staphylococcus aureus in milk curd;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7;
FIG. 11 is the effect of the self-assembled film of the present invention on the total number of Trichosporon lactis mold;
in the figure:
a-buffer solution of pH = 3; b-buffer solution of pH = 7.
[ detailed description ] embodiments
The invention will be better understood from the following examples.
Example 1: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparing a flaxseed gum water solution:
the ratio of the linseed glue in grams to the ultrapure water in milliliters is 1.0: 180, adding the flaxseed gum into ultrapure water, sealing the reactor by using a preservative film, and stirring for 6 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid in grams to ultrapure water in milliliters was 0.1: 10: 100, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 10 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 20g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and fixing the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; the pH =2 phosphate buffer was prepared using disodium hydrogen phosphate solution, sodium dihydrogen phosphate solution and citric acid, and the phosphate buffer was further uv-sterilized for 5 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =2 to ensure that the surfaces of the milk bean curd blocks are electropositive;
D. in situ self assembly
And D, soaking the milk curd with the positively charged surface obtained in the step C in the linseed gum solution prepared in the step A, standing, adsorbing and balancing the linseed gum for 8 seconds, adsorbing the linseed gum on the surface of the milk curd to be negatively charged, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: 20 washing with ultrapure water, removing nonspecific adsorption of flaxseed gum, and air drying for 0.8 min; and then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, keeping chitosan adsorption balance for 12 seconds, adsorbing chitosan on the surface of the linseed gum adsorbed milk tofu to be electropositive, and then mixing the obtained product with ultrapure water in milliliters according to the ratio of 1:10, washing with ultrapure water, removing the non-specifically adsorbed chitosan, and airing for 1.4 min; this was repeated 5 times in such a way that 5 layers of films were self-assembled on the surface of the dried milk cake, each film layer consisting of a layer of flaxseed gum and a layer of chitosan, the layers of flaxseed gum alternating with the layers of chitosan as a whole.
Example 2: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparing a flaxseed gum water solution:
the ratio of the linseed glue in grams to the ultrapure water in milliliters is 5.0: 100, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 1 hour by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid in grams to ultrapure water in milliliters was 10: 22: 180, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 2 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 30g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; the phosphate buffer with pH =3 was prepared from disodium hydrogen phosphate solution, sodium dihydrogen phosphate solution and citric acid, and the phosphate buffer was further subjected to UV sterilization for 15 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =3 to ensure that the surfaces of the milk bean curd blocks are electropositive;
D. in situ self assembly
And D, soaking the milk curd with the positively charged surface obtained in the step C in the linseed gum solution prepared in the step A, standing, adsorbing and balancing the linseed gum for 10 seconds, adsorbing the linseed gum on the surface of the milk curd to be negatively charged, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: 14, washing with ultrapure water, removing the non-specifically adsorbed flaxseed gum, and airing for 1.0 min; and then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, keeping chitosan adsorption balance for 10 seconds, adsorbing chitosan on the surface of the linseed gum adsorbed milk tofu to be electropositive, and then mixing the obtained product with ultrapure water in milliliters according to the ratio of 1: 20 washing with ultrapure water, removing non-specifically adsorbed chitosan, and air drying for 1.2 min; repeating the above steps for 6 times, so that 6 layers of films are self-assembled on the surface of the milk curd, each film layer is composed of a flaxseed gum layer and a chitosan layer, and the flaxseed gum layers and the chitosan layers are alternately distributed on the whole.
Example 3: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparing a flaxseed gum water solution:
the ratio of the linseed glue in grams to the ultrapure water in milliliters is 0.1: 500, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 10 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid and ultrapure water in milliliters is 1: 1: 420, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 4 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 50g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; the phosphate buffer with pH =4 was prepared from disodium hydrogen phosphate solution, sodium dihydrogen phosphate solution and citric acid, and the phosphate buffer was further subjected to UV sterilization for 20 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =4 to ensure that the surfaces of the milk bean curd blocks are electropositive;
D. in situ self assembly
And D, soaking the milk curd with the positively charged surface obtained in the step C in the linseed gum solution prepared in the step A, standing, adsorbing and balancing the linseed gum for 12 seconds, adsorbing the linseed gum on the surface of the milk curd to be negatively charged, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: washing with ultrapure water, removing non-specifically adsorbed flaxseed gum, and air drying for 1.4 min; and then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, balancing the adsorption of chitosan for 8 seconds, adsorbing chitosan on the surface of the linseed gum adsorbed milk tofu to be electropositive, and then, according to the ratio of the milk tofu in grams to the ultrapure water in milliliters of 1: 14, washing with ultrapure water, removing the non-specifically adsorbed chitosan, and airing for 0.8 min; this was repeated 10 times in such a way that 10 films were self-assembled on the surface of the dried milk cake, each film layer consisting of a linseed gum layer and a chitosan layer, the linseed gum layers and chitosan layers being alternately distributed as a whole.
Example 4: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparing a flaxseed gum water solution:
the ratio of the linseed glue in grams to the ultrapure water in milliliters is 10: 400, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 3 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid in grams to ultrapure water in milliliters was 5: 30: 500, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 7 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 42g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; the pH =7 phosphate buffer was prepared using disodium hydrogen phosphate solution, sodium dihydrogen phosphate solution and citric acid, and the phosphate buffer was further uv-sterilized for 10 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =7 to ensure that the surfaces of the milk bean curd blocks are electronegative;
D. in situ self assembly
And D, soaking the milk curd with the electronegative surface obtained in the step C in the chitosan aqueous solution prepared in the step B, standing, adsorbing and balancing chitosan for 10 seconds, adsorbing chitosan on the surface of the milk curd to be electropositive, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: 16, washing with ultrapure water, removing the non-specifically adsorbed chitosan, and airing for 1.2 min; then, placing the dried milk curd adsorbing chitosan into the linseed gum solution prepared in the step A, standing, keeping the linseed gum adsorption balance for 10 seconds, adsorbing the linseed gum on the surface of the milk curd adsorbing chitosan to be negative, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: 16 washing with ultrapure water, removing non-specifically adsorbed flaxseed gum, and air drying for 1.0 min; this was repeated 8 times, so that 8 layers of films were self-assembled on the surface of the dried milk cake, each film layer consisting of a linseed gum layer and a chitosan layer, the linseed gum layers and chitosan layers being alternately distributed as a whole.
Example 5: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparing a flaxseed gum water solution:
the ratio of the linseed glue in grams to the ultrapure water in milliliters is 2: 260, adding the flaxseed gum into ultrapure water, sealing the reactor by using a preservative film, and stirring for 8 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid in grams to ultrapure water in milliliters was 3: 5: 260, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 8 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 26g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and fixing the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; the phosphate buffer with pH =7 was prepared from disodium hydrogen phosphate solution, sodium dihydrogen phosphate solution and citric acid, and the phosphate buffer was further subjected to UV sterilization for 8 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =7 to ensure that the surfaces of the milk bean curd blocks are electronegative;
D. in situ self assembly
And D, soaking the milk curd with the electronegative surface obtained in the step C in the chitosan aqueous solution prepared in the step B, standing, adsorbing and balancing chitosan for 11 seconds, adsorbing chitosan on the surface of the milk curd to be electropositive, and then mixing the milk curd with the ultrapure water in milliliters according to the ratio of 1: 12, washing with ultrapure water, removing the non-specifically adsorbed chitosan, and airing for 1.1 min; then, placing the dried milk curd adsorbing chitosan into the linseed gum solution prepared in the step A, standing, keeping the linseed gum adsorption balance for 9 seconds, adsorbing the linseed gum on the surface of the milk curd adsorbing chitosan to be negative, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: washing with ultrapure water, removing nonspecific adsorption of flaxseed gum, and air drying for 9 min; this was repeated 7 times, so that 7 films were self-assembled on the surface of the dried milk cake, each film layer consisting of a flaxseed gum layer and a chitosan layer, the flaxseed gum layers and chitosan layers being alternately distributed over the whole.
Example 6: self-assembly multilayer film on surface of milk curd
The implementation steps of this example are as follows:
A. preparation of aqueous solution of flaxseed gum
The ratio of the linseed glue in grams to the ultrapure water in milliliters is 6: 340, adding the flaxseed gum into ultrapure water, sealing the reactor by using a preservative film, and stirring for 5 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid in grams to ultrapure water in milliliters was 8: 16: 350, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 5 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Dissolving 38g of disodium hydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; dissolving 7.5g of sodium dihydrogen phosphate in a 250ml volumetric flask by using ultrapure water, and metering the volume to 250ml by using the ultrapure water; and (3) preparing a phosphate buffer solution with the pH =6 by using a disodium hydrogen phosphate solution, a sodium dihydrogen phosphate solution and citric acid, and performing ultraviolet sterilization on the phosphate buffer solution for 18 min.
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in phosphate buffer solution with the pH =6 to ensure that the surfaces of the milk bean curd blocks are electronegative;
D. in situ self assembly
And D, soaking the milk curd with the electronegative surface obtained in the step C in the chitosan aqueous solution prepared in the step B, standing, adsorbing and balancing chitosan for 9 seconds, adsorbing chitosan on the surface of the milk curd to be electropositive, and then mixing the milk curd with the ultrapure water in milliliters according to the ratio of 1: washing with ultrapure water to remove non-specifically adsorbed chitosan, and air drying for 0.9 min; then, placing the dried milk curd adsorbing chitosan into the linseed gum solution prepared in the step A, standing, keeping the adsorption balance of the linseed gum for 11 seconds, adsorbing the linseed gum on the surface of the milk curd adsorbing chitosan to be negative, and then, according to the ratio of the milk curd in grams to the ultrapure water in milliliters of 1: 12, washing with ultrapure water, removing the non-specifically adsorbed flaxseed gum, and airing for 11 min; this was repeated 9 times in such a way that 9 films were self-assembled on the surface of the dried milk cake, each film layer consisting of a linseed gum layer and a chitosan layer, the linseed gum layers and chitosan layers being alternately distributed as a whole.
Test example 1: the invention relates to self-assembly sensory scoring of milk curd
Sensory panel was composed of 4 cheese-related professionals, male and female, each scored according to the sensory scoring table criteria set forth in the table below.
TABLE 1 sensory quality evaluation Standard of fermented milk tofu
| Scoring | Color and luster | Taste of the product | Tissue state |
| 8.1～10 | Milky white fresh milk curd | Frankincense with slight sour taste | Uniform texture and suitable hardness |
| 6.1～8 | Slightly yellow | Slightly peculiar smell | The texture is slightly changed without affecting the sale |
| 4.1～6 | Yellowing with slight mildew | Slightly heavy peculiar smell | The texture changes and becomes soft, which affects the sale |
| 2.1～4 | Obvious mildew | Obvious peculiar smell | The texture changes and obviously softens, which affects the sale |
Note: and if the sensory score is less than or equal to 6 points, the milk tofu is not suitable for sale.
Fig. 7 is a trend of sensory scores of the self-assembled milk-dried bean curd, in which fig. 7a is a buffer solution with pH =3 and fig. 7b is a buffer solution with pH = 7. From the overall trend, both buffer-adjusted sensory scores of the milk-tofu decreased with the increase of the storage time. However, the decay and deterioration reasons are almost the same in the storage process, and the figure shows that the sensory score of the blank group is reduced fastest, the sensory score of the blank group is convenient for the initial sensory generation difference to be very significant (P is less than 0.01) by the fourth day, and the blank group does not have any bacteriostatic agent protection, so that a good environment is provided for the growth of the mold. After the third day the mold started growing in large numbers. The milk curd adjusted by the buffer solution with pH =3 is better than the milk curd adjusted by the buffer solution with pH =7 in the buffer solution with pH =7, which is also related to mold on the surface of the milk curd, and since the mold generally lives in a slightly acidic environment, the mold with pH =3 grows more. The sensory scores of the milk curds regulated by the two buffer solutions are increased along with the increase of the number of self-assembled layers, because the deposition amount of chitosan is increased along with the increase of the number of layers, and the chitosan has an inhibiting effect on the mold. As can be seen from fig. 7, pH = 710.5 bilayers had the highest sensory score values.
Claims (6)
1. A method for self-assembling a multilayer film on the surface of a milk curd is characterized by comprising the following steps:
A. preparation of aqueous solution of flaxseed gum
The ratio of the linseed glue in grams to the ultrapure water in milliliters is 0.1-10: 100-500, adding flaxseed gum into ultrapure water, sealing a reactor with a preservative film, and stirring for 1-10 hours by using a magnetic stirrer to obtain a flaxseed gum aqueous solution;
B. preparation of aqueous Chitosan solution
The ratio of chitosan, citric acid and ultrapure water in milliliters is 0.1-10: 1-30: 100-500, adding chitosan and citric acid into ultrapure water, sealing a reactor with a preservative film, and stirring for 2-10 hours by using a magnetic stirrer to obtain a chitosan aqueous solution;
C. pretreatment of milk curd
Cutting the milk bean curd into blocks, and then soaking the milk bean curd blocks in a phosphate buffer solution with the pH value of 2-4 to ensure that the surfaces of the milk bean curd blocks are electropositive;
D. in situ self assembly
B, soaking the milk tofu with the positively charged surface in the linseed gum solution prepared in the step A, standing, keeping the adsorption balance of the linseed gum, adsorbing the linseed gum on the surface of the milk tofu to be negatively charged, washing with ultrapure water, removing the non-specifically adsorbed linseed gum, and airing; and then, placing the dried and adsorbed linseed gum milk tofu in the chitosan aqueous solution prepared in the step B, standing, balancing the adsorption of chitosan, adsorbing chitosan on the surface of the linseed gum-adsorbed milk tofu to be electropositive, then washing with ultrapure water to remove the non-specifically adsorbed chitosan, wherein the ratio of the milk tofu in grams to the ultrapure water in milliliters is 1: 10-20; airing; the assembly is repeated for 5-10 times in such a way, and then a plurality of layers of films are self-assembled on the surface of the dried milk cake.
2. The method according to claim 1, wherein in the step A, the ratio of the linseed glue to the ultrapure water is 1-8: 180-400.
3. The method according to claim 1, wherein in the step B, the ratio of chitosan, citric acid and ultrapure water is 1-8: 8-22: 180 to 420.
4. The method according to claim 1, wherein in step D, the milk curd is left in the linseed glue solution for adsorption equilibrium for 8-12 seconds.
5. The method according to claim 1, wherein in the step D, the milk curd is left to stand in the chitosan aqueous solution for adsorption equilibrium for 8 to 12 seconds.
6. The method according to claim 1, wherein in the step D, the washed milk curd is dried on a clean bench for 0.8 to 1.4 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710690667.2A CN107455482B (en) | 2017-08-14 | 2017-08-14 | Method for self-assembling multilayer film on surface of milk curd |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710690667.2A CN107455482B (en) | 2017-08-14 | 2017-08-14 | Method for self-assembling multilayer film on surface of milk curd |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107455482A CN107455482A (en) | 2017-12-12 |
| CN107455482B true CN107455482B (en) | 2020-04-28 |
Family
ID=60549111
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710690667.2A Active CN107455482B (en) | 2017-08-14 | 2017-08-14 | Method for self-assembling multilayer film on surface of milk curd |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107455482B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001505775A (en) * | 1996-12-13 | 2001-05-08 | フロマジェリ・ベル | Method of coating cheese and resulting coated cheese |
| CN104585310A (en) * | 2015-01-20 | 2015-05-06 | 东南大学 | Fruit and vegetable preservative and use method based on layer by layer self-assembly principle |
| CN106962486A (en) * | 2017-02-09 | 2017-07-21 | 上海应用技术大学 | A kind of yoghourt stabilizer containing flaxseed gum and its application in Yoghourt is prepared |
-
2017
- 2017-08-14 CN CN201710690667.2A patent/CN107455482B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001505775A (en) * | 1996-12-13 | 2001-05-08 | フロマジェリ・ベル | Method of coating cheese and resulting coated cheese |
| CN104585310A (en) * | 2015-01-20 | 2015-05-06 | 东南大学 | Fruit and vegetable preservative and use method based on layer by layer self-assembly principle |
| CN106962486A (en) * | 2017-02-09 | 2017-07-21 | 上海应用技术大学 | A kind of yoghourt stabilizer containing flaxseed gum and its application in Yoghourt is prepared |
Non-Patent Citations (1)
| Title |
|---|
| 可食性牦牛奶酪改性保鲜膜的性能研究;胡先望等;《中国酿造》;20140915;第33卷(第9期);第66-70页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107455482A (en) | 2017-12-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Jiang et al. | The preservation performance of chitosan coating with different molecular weight on strawberry using electrostatic spraying technique | |
| El-Sayed et al. | Development of eco-friendly probiotic edible coatings based on chitosan, alginate and carboxymethyl cellulose for improving the shelf life of UF soft cheese | |
| Fang et al. | Antifungal activity of chitosan and its preservative effect on low-sugar candied kumquat | |
| Nottagh et al. | Development of a biodegradable coating formulation based on the biological characteristics of the Iranian Ultra-filtrated cheese | |
| Kingwascharapong et al. | Effect of edible coatings developed from chitosan incorporated with tea seed oil on Japanese pear | |
| CN111280240A (en) | Preparation method of litsea cubeba essential oil nanoemulsion and application of litsea cubeba essential oil nanoemulsion in fresh keeping of salmon | |
| Huang et al. | Development and characterization of an edible chitosan–whey protein nano composite film for chestnut (Castanea mollissima Bl.) preservation | |
| CN114591541B (en) | Anti-corrosion preservative film, preparation method and application thereof | |
| Zore et al. | Bacterial adhesion rate on food grade ceramics and Teflon as kitchen worktop surfaces | |
| Ku et al. | Physical properties of nisin-incorporated gelatin and corn zein films and antimicrobial activity against Listeria monocytogenes | |
| CN107455482B (en) | Method for self-assembling multilayer film on surface of milk curd | |
| CN111194767A (en) | Litsea cubeba essential oil nanoemulsion | |
| CN102894068B (en) | Egg coating preservative with oxyethlene higher aliphatic alcohol | |
| Salih et al. | Physicochemical, microbial and sensory characteristics of yoghurt processed by adding various formulations of gum Arabic and guar gum | |
| Magan et al. | Lipolytic activity and degradation of rapeseed oil and rapeseed by spoilage fungi | |
| Wang et al. | The effects of calcium propionate and cinnamaldehyde on the mechanical, physical and antimicrobial properties of composite films based on potato starch | |
| CN113632827B (en) | Application of butyl essential oil microcapsule in non-contact strawberry preservation | |
| Chandran et al. | Quality evaluation of edible film coated tomato (Solanum lycopersicum) fruits | |
| CN114287469A (en) | Egg surface bio-based antibacterial coating solution and preparation method thereof | |
| Zhang et al. | Coating of fruit with an edible soybean protein isolate film doped with hydroxypropyl methyl cellulose for improved preservation | |
| CN106520579A (en) | Serratia marcescens fermentation liquor culture medium promoting growth and development of hypsizygus marmoreus | |
| Aboul-Anean | Biopolymer Product from pullulan Material (Polysaccharide) used for Natural Film & Coat-ings in Food Preservation | |
| Chung et al. | Optimum conditions for combined application of Leuconostoc sp. and Saccharomyces sp. to sourdough | |
| Lasztity | Micro-organisms important in food microbiology | |
| CN109021271B (en) | Polyethylene antibacterial film and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |