Functional bee pollen fermented goat yogurt and preparation method thereof
阅读说明：本技术 一种功能性蜂花粉发酵酸羊乳及其制备方法 (Functional bee pollen fermented goat yogurt and preparation method thereof ) 是由 张颖 王慧慧 王宇翔 曹炜 刘清清 于 2021-08-12 设计创作，主要内容包括：本发明涉及一种功能性蜂花粉发酵酸羊乳及其制备方法,以中国的特色蜂花粉为原料,采用机械破壁-超声水提法制备蜂花粉提取物,再利用β-环状糊精作为保护剂处理制得β-CD-蜂花粉包埋物,然后于其它物料均质后以适当比例添加到羊乳中,经杀菌、发酵、后熟等加工工序制成蜂花粉酸羊乳。本发明开发的功能性蜂花粉发酵酸羊乳产品配方按质量百分比包括6％～9％蜂花粉水提物包埋物、82％～88％羊乳、7％～9％辅料和0.002％～0.1％乳酸菌发酵剂,该产品具有优良的口感及抗氧化生物活性,并且能够在货架期内保持稳定的产品品质及功能特性。本发明不仅最大程度保留了蜂花粉本身营养及活性成分、降低其致敏成分,且与羊乳营养及保健价值有机结合,将会更加满足人们对新型功能性食品的消费需求。(The invention relates to a functional bee pollen fermented goat yogurt and a preparation method thereof, which takes Chinese characteristic bee pollen as a raw material, adopts a mechanical wall breaking-ultrasonic water extraction method to prepare a bee pollen extract, then utilizes beta-cyclodextrin as a protective agent to process to prepare a beta-CD-bee pollen embedded substance, then adds other materials into goat milk in proper proportion after homogenizing, and prepares the bee pollen fermented goat yogurt by the processing procedures of sterilization, fermentation, after-ripening and the like. The formula of the functional bee pollen fermented sour goat milk product developed by the invention comprises 6-9% of bee pollen aqueous extract embedded matter, 82-88% of goat milk, 7-9% of auxiliary material and 0.002-0.1% of lactic acid bacteria starter by mass percent, and the product has excellent taste and antioxidant bioactivity and can keep stable product quality and functional characteristics in shelf life. The invention not only retains the nutrition and active components of the bee pollen to the maximum extent and reduces the allergic components, but also organically combines with the nutrition and health care value of the goat milk, and can better meet the consumption demand of people on novel functional food.)
1. A functional bee pollen fermented goat yogurt is characterized in that: the functional bee pollen fermented sour goat milk component comprises 6-9% of bee pollen aqueous extract embedded matter, 82-88% of goat milk, 7-9% of auxiliary material and 0.002-0.1% of lactic acid bacteria leavening agent according to mass percentage.
2. The functional bee pollen fermented goat yogurt of claim 1, wherein: the bee pollen aqueous extract embedded substance is prepared from bee pollen aqueous extract freeze-dried powder and a beta-CD protective agent according to the proportion of 1: 2-1: 3 (w/w).
3. The functional bee pollen fermented goat yogurt of claim 2, wherein: the bee pollen aqueous extract freeze-dried powder is camellia bee pollen aqueous extract freeze-dried powder.
4. The functional bee pollen fermented goat yogurt of claim 3, wherein: the content of the beta-CD-bee pollen aqueous extract embedded matter is 7.32 percent.
5. The functional bee pollen fermented goat yogurt as claimed in any one of claims 1 to 4, characterized in that: the auxiliary materials comprise one or more of sucrose, honey, isomaltooligosaccharide, fructo-oligosaccharide, walnut protein peptide and a composite yoghurt stabilizer.
6. The method for preparing the functional bee pollen fermented goat yogurt as claimed in claim 1, which is characterized in that: the preparation method comprises the following steps:
1) preparing a bee pollen aqueous extract: selecting bee pollen, and preparing a bee pollen aqueous extract by adopting a mechanical wall breaking-ultrasonic water extraction combined method;
2) preparing the bee pollen aqueous extract embedding substance: beta-CD is selected to carry out embedding protection treatment on the bee pollen aqueous extract;
3) preparing bee pollen fermented goat yogurt: and (3) dissolving the auxiliary materials into the sheep milk, uniformly stirring, homogenizing under high pressure, adding the beta-CD-bee pollen embedded substance into the feed liquid according to the addition amount of 6-9% (w/w), quickly cooling to 40-50 ℃ after sterilization, adding a lactic acid bacteria starter, uniformly mixing, placing in a constant temperature condition for fermentation, and cooling and ripening to obtain the bee pollen fermented sour sheep milk finished product.
7. The method for preparing the functional bee pollen fermented goat yogurt as claimed in claim 6, wherein the method comprises the following steps: the specific steps of the step 1) are as follows: firstly, mechanically crushing bee pollen into 100 meshes, adding deionized water according to the material-liquid ratio of 1: 15-1: 20(g/mL), carrying out ultrasonic assisted extraction at 65-70 ℃ for 1.5-2 h, then centrifuging at 3000-4000 r/min for 10-15 min, collecting supernatant, carrying out vacuum rotary evaporation at 48-52 ℃ to obtain a bee pollen extraction concentrated solution, and carrying out vacuum freeze drying to obtain the bee pollen aqueous extract freeze-dried powder.
8. The method for preparing functional bee pollen fermented goat yogurt as claimed in claim 7, wherein: the specific steps of the step 2) are as follows: dissolving a certain amount of bee pollen water extract freeze-dried powder in deionized water according to the material-liquid ratio of 2:3(w/w), and then, according to the weight ratio of the bee pollen water extract: the beta-CD protective agent is prepared by weighing beta-CD at a ratio of 1: 2-1: 3(w/w), preparing a 20-28 mg/mL beta-CD solution with deionized water, stirring and mixing the beta-CD solution and the deionized water at a temperature of 48-53 ℃ at 700-900 r/min for 40min, dispersing at a high speed of 8000-10000 r/min for 1-2 min, and performing vacuum freeze drying to obtain the beta-CD-bee pollen aqueous extract inclusion compound.
9. The method for preparing functional bee pollen fermented goat yogurt according to claim 8, wherein the method comprises the following steps: the conditions for homogenizing the mixed feed liquid in the step 3) are as follows: 60-70 ℃, primary 20-30 MPa and secondary 5MPa, and the sterilization treatment conditions are as follows: 90-95 ℃ for 5-10 min.
10. The method for preparing functional bee pollen fermented goat yogurt as claimed in claim 9, wherein: the fermentation conditions in the step 3) are as follows: the fermentation temperature is 41-43 ℃, the fermentation time is 5-6 h, after the fermentation acidity reaches 70 DEG T, after-ripening is carried out for 24h under the condition of 4 ℃.
Technical Field
The invention belongs to the technical field of food processing, and particularly relates to functional bee pollen fermented goat yogurt and a preparation method thereof.
Background
Goat milk, an important bulk milk product, is a world-recognized milk resource closest to human milk, and can provide comprehensive nutrients for human growth and development and health maintenance. Compared with cow milk, the goat milk contains various vitamins, minerals, and active ingredients such as Epidermal Growth Factor (EGF), superoxide dismutase (SOD), etc., is easy to digest and absorb, and has health promotion effects of caring skin, improving intelligence, nourishing brain, resisting oxidation, enhancing immunity, etc. With the increasing acceptance of consumers on the nutrition and health care value of the goat milk, the goat milk industry enters a high-speed growth period, however, the goat milk products in the current market are single in type, the goat milk powder occupies a leading position, the goat milk products are very lagged behind in the aspect of new product development, and the development of the goat milk industry is severely restricted. The sour goat milk prepared by fermenting the goat milk with the lactic acid bacteria can improve the bad flavor of the goat milk and improve the bioavailability and functional characteristics of the product, and is an important way for developing the innovation of goat milk products.
Bee pollen is irregular oblate doughy substance formed by pollen grains collected by bees from honey-source plants, secretions on self glands, saliva and nectar which are stored and fermented in a honeycomb. Bee pollen is used as a natural health food, has comprehensive and balanced nutrient substances, contains 11-35% of protein, 20-39% of carbohydrate and 1-20% of lipid, is rich in biological active ingredients such as phenols, flavones, polypeptides, phospholipids and sterols, has the effects of resisting oxidation, enhancing immunity, reducing blood sugar, protecting liver and the like, and enjoys the reputation of 'complete nutrients'. As a world bee-keeping big country in China, bee pollen is rich in resources and various in variety, however, deep-processed products of the bee pollen mainly take buccal tablets, chewable tablets, granules, health-care oral liquid and the like as main materials, new product development performed by applying the deep-processed products to common food is less, and a research report for developing functional bee pollen fermented goat milk products by adding the Chinese characteristic bee pollen into goat milk is not found at present. The bee pollen fermented goat yogurt organically combines the nutrition and health care effects of the bee pollen and the goat milk, not only has the unique flavor and taste of the goat yogurt, but also contains effective bioactive substances in the bee pollen, and simultaneously, the fermentation effect of the lactic acid bacteria also effectively reduces the allergic components in the bee pollen, so that the product has more nutrition and health care characteristics, and can meet the consumption requirements of people on novel functional food.
As the bee pollen has strong pollen smell and taste, the direct addition of the bee pollen into food can easily cause adverse effects on the color, flavor, taste and the like of the product, thereby reducing the acceptance degree of consumers; the active ingredients of polyphenol and flavonoid in bee pollen are also easily degraded or changed by the influence of environmental factors such as pH, illumination, temperature and oxygen, so that the quality of the product during the shelf life is unstable. Therefore, the functional components in the bee pollen are efficiently extracted by selecting a proper technology and method for protection treatment, and then the bee pollen is added into the goat milk by adopting a proper process for lactobacillus fermentation to prepare the goat yogurt, so that the final goat yogurt product has good taste, stable quality and stronger biological activity, and is a key technical problem for developing functional bee pollen goat yogurt products.
Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide a functional bee pollen fermented goat yogurt and a preparation method thereof, wherein the product has excellent sensory quality and antioxidant bioactivity and can maintain stable product quality and functional characteristics within a shelf life (21 days under a refrigeration condition of 4 ℃).
The technical solution of the invention is as follows: the invention relates to functional bee pollen fermented goat yogurt, which is characterized in that: the functional bee pollen fermented sour goat milk component comprises 6-9% of bee pollen aqueous extract embedded matter, 82-88% of goat milk, 7-9% of auxiliary material and 0.002-0.1% of lactic acid bacteria leavening agent according to mass percentage.
Furthermore, the bee pollen aqueous extract embedded substance is prepared from bee pollen aqueous extract freeze-dried powder and beta-cyclodextrin (beta-CD) protective agent according to the proportion of 1: 2-1: 3 (w/w).
Furthermore, the bee pollen aqueous extract freeze-dried powder is camellia bee pollen aqueous extract freeze-dried powder or other kinds of bee pollen aqueous extract freeze-dried powder.
Furthermore, the content of the embedded matter of the beta-CD-bee pollen aqueous extract is 7.32 percent.
Further, the auxiliary materials comprise one or more of sucrose, honey, isomaltose hypgather, fructo-oligosaccharide, walnut protein peptide and a composite yoghurt stabilizer.
The preparation method of the functional bee pollen fermented goat yogurt is characterized by comprising the following steps: the preparation method comprises the following steps:
1) preparing a bee pollen aqueous extract: selecting bee pollen, and preparing a bee pollen aqueous extract by adopting a mechanical wall breaking-ultrasonic water extraction combined method;
2) preparing the bee pollen aqueous extract embedding substance: beta-CD is selected to carry out embedding protection treatment on the bee pollen aqueous extract;
3) preparing bee pollen fermented goat yogurt: and (3) dissolving the auxiliary materials into the sheep milk, uniformly stirring, homogenizing under high pressure, adding the beta-CD-bee pollen embedded substance into the feed liquid according to the addition amount of 6-9% (w/w), quickly cooling to 40-50 ℃ after sterilization, adding a lactic acid bacteria starter, uniformly mixing, placing in a constant temperature condition for fermentation, and cooling and ripening to obtain the bee pollen fermented sour sheep milk finished product.
Further, the specific steps of step 1) are as follows: firstly, mechanically crushing bee pollen into 100 meshes, adding deionized water according to the material-liquid ratio of 1: 15-1: 20(g/mL), carrying out ultrasonic assisted extraction at 65-70 ℃ for 1.5-2 h, then centrifuging at 3000-4000 r/min for 10-15 min, collecting supernatant, carrying out vacuum rotary evaporation at 48-52 ℃ to obtain a bee pollen extraction concentrated solution, and carrying out vacuum freeze drying to obtain the bee pollen aqueous extract freeze-dried powder.
Further, the specific steps of step 2) are as follows: dissolving a certain amount of bee pollen water extract freeze-dried powder in deionized water according to the material-liquid ratio of 2:3(w/w), and then, according to the weight ratio of the bee pollen water extract: the beta-CD protective agent is prepared by weighing beta-CD at a ratio of 1: 2-1: 3(w/w), preparing a 20-28 mg/mL beta-CD solution with deionized water, stirring and mixing the beta-CD solution and the deionized water at a temperature of 48-53 ℃ at 700-900 r/min for 40min, dispersing at a high speed of 8000-10000 r/min for 1-2 min, and performing vacuum freeze drying to obtain the beta-CD-bee pollen aqueous extract inclusion compound.
Further, the conditions for homogenizing the mixed feed liquid in the step 3) are as follows: 60-70 ℃, primary 20-30 MPa and secondary 5MPa, and the sterilization treatment conditions are as follows: 90-95 ℃ for 5-10 min.
Further, the fermentation conditions in the step 3) are as follows: the fermentation temperature is 41-43 ℃, the fermentation time is 5-6 h, after the fermentation acidity reaches 70 DEG T, after-ripening is carried out for 24h under the condition of 4 ℃.
The invention provides a functional bee pollen fermented goat yogurt and a preparation method thereof, which takes Chinese special bee pollen as a raw material, adopts a mechanical wall breaking-ultrasonic water extraction method to prepare a bee pollen extract, utilizes beta-cyclodextrin as a protective agent to treat the bee pollen water extract to prepare a beta-CD-bee pollen embedded substance, then adds the beta-CD-bee pollen embedded substance into the goat milk in a proper proportion after the material is homogenized, and then prepares the functional bee pollen fermented goat yogurt through the processing procedures of sterilization, fermentation, after-ripening and the like. Compared with the prior art, the invention has the beneficial effects that:
1) the Chinese characteristic bee pollen is applied to the goat milk for the first time to develop the functional bee pollen fermented goat milk, and the product organically combines the nutrition and health care values of the bee pollen and the goat milk, so that the consumption demand of people on novel functional food can be better met;
2) the bee pollen aqueous extract prepared by the mechanical wall breaking-ultrasonic combined water extraction method is rich in various components such as protein, polysaccharide, polyphenol, flavone, vitamin, mineral substances and the like, so that the nutrition and active ingredients of the bee pollen are retained to the maximum extent, and the nutrition and health care value of the final bee pollen goat yogurt product are effectively improved;
3) the novel health goat yogurt product is developed by adopting a modern food microencapsulation technology and taking beta-cyclodextrin as a wall material to carry out embedding protection treatment on the bee pollen aqueous extract, and is favorable for ensuring that the bee pollen goat yogurt has stable sensory characteristics, product quality and antioxidant bioactivity during a refrigeration shelf period.
Drawings
FIG. 1 is the effect of mass concentration of beta-CD on the embedding rate of beta-CD-bee pollen aqueous extract;
FIG. 2 is the effect of the stirring speed on the embedding rate of the beta-CD-bee pollen aqueous extract;
FIG. 3 is the effect of agitation temperature on the embedding rate of beta-CD-bee pollen aqueous extract.
Detailed Description
The present invention will be described in further detail with reference to specific examples below:
the invention provides functional bee pollen fermented sour goat milk which comprises, by mass, 6% -9% of bee pollen aqueous extract embedded matter, 82% -88% of goat milk, 7% -9% of auxiliary materials and 0.002% -0.1% of lactic acid bacteria leavening agent.
The bee pollen aqueous extract embedded matter is obtained by processing an embedding protective agent beta-CD, and the bee pollen aqueous extract freeze-dried powder and the beta-CD are prepared according to the proportion of 1: 2-1: 3 (w/w). The bee pollen water extract freeze-dried powder is camellia bee pollen or other kinds of bee pollen water extract freeze-dried powder. The optimum content of the beta-CD-bee pollen aqueous extract is 7.32%. The auxiliary materials comprise one or more of sucrose, honey, isomaltooligosaccharide, fructo-oligosaccharide, walnut protein peptide and composite yoghurt stabilizer.
The invention also provides a preparation method of the functional bee pollen fermented goat yogurt, which comprises the following steps:
1) preparing a bee pollen aqueous extract: selecting bee pollen, and preparing a bee pollen aqueous extract by adopting a mechanical wall breaking-ultrasonic water extraction combined method;
firstly, mechanically crushing bee pollen into 100 meshes, adding deionized water according to the material-liquid ratio of 1: 15-1: 20(g/mL), carrying out ultrasonic assisted extraction at 65-70 ℃ for 1.5-2 h, then centrifuging at 3000-4000 r/min for 10-15 min, collecting supernatant, carrying out vacuum rotary evaporation at 48-52 ℃ to obtain a bee pollen extraction concentrated solution, and carrying out vacuum freeze drying to obtain the bee pollen aqueous extract freeze-dried powder.
2) Preparing the bee pollen aqueous extract embedding substance: dissolving a certain amount of bee pollen water extract freeze-dried powder in deionized water according to the material-liquid ratio of 2:3(w/w), and then, according to the weight ratio of the bee pollen water extract: the beta-CD protective agent is prepared by weighing beta-CD at a ratio of 1: 2-1: 3(w/w), preparing a 20-28 mg/mL beta-CD solution with deionized water, stirring and mixing the beta-CD solution and the deionized water at a temperature of 48-53 ℃ at 700-900 r/min for 40min, dispersing at a high speed of 8000-10000 r/min for 1-2 min, and performing vacuum freeze drying to obtain the beta-CD-bee pollen aqueous extract inclusion compound.
3) Preparing bee pollen fermented goat yogurt: the antibiotic-free fresh goat milk or the recovered goat milk qualified by acceptance check is dissolved in the goat milk, the mixture liquid is homogenized under high pressure after being stirred uniformly, and the homogenization condition is as follows: 60-70 ℃, the primary pressure is 20-30 MPa, and the secondary pressure is 5 MPa; then adding the beta-CD-bee pollen embedded substance into the feed liquid according to the addition amount of 6-9% (w/w), quickly cooling to 40-50 ℃ after sterilization (the sterilization condition is 90-95 ℃ and 5-10 min), adding a lactic acid bacteria starter, uniformly mixing, and fermenting under the constant temperature condition, wherein the fermentation condition is as follows: and (3) fermenting at the fermentation temperature of 41-43 ℃ for 5-6 h until the fermentation acidity reaches 70 DEG T, and after-ripening for 24h at the temperature of 4 ℃ to obtain the bee pollen fermented goat milk finished product.
Example 1 preparation of Camellia bee pollen aqueous extract
In the embodiment, camellia bee pollen is used as a raw material, and a camellia bee pollen aqueous extract is prepared by adopting a mechanical wall breaking-ultrasonic water extraction combined method. Weighing 100g of sterilized camellia bee pollen, mechanically pulverizing, adding 2000mL of deionized water, performing ultrasonic-assisted extraction at 65 ℃ for 1.5h, centrifuging at 4000r/min for 15min, repeating the step for 2 times, collecting supernatant, performing vacuum evaporation at 50 ℃ to obtain 120g of camellia pollen water extract concentrate, and performing vacuum freeze-drying to obtain camellia pollen extract freeze-dried powder.
Example 2 optimization of beta-CD-Camellia bee pollen aqueous extract embedding Process
In the embodiment, the camellia bee pollen aqueous extract is used as a core material, and beta-CD is used as an embedding protective agent to prepare the beta-CD-camellia pollen aqueous extract embedding material. Selecting the mass concentration, the magnetic stirring speed and the stirring temperature of the beta-CD solution as single-factor test indexes, and the total phenol embedding rate of the bee pollen aqueous extract as a measurement index to determine the optimal preparation process of the beta-CD-bee pollen freeze-dried powder, wherein the results are shown in figures 1, 2 and 3.
As can be seen from single-factor experiments in figures 1, 2 and 3, the embedding rate of the beta-CD-camellia pollen aqueous extract shows the trend of increasing firstly and then decreasing with the increase of the mass concentration, the stirring speed and the stirring temperature of the beta-CD solution, so that the optimal preparation process conditions of the beta-CD-camellia pollen aqueous extract embedding are determined as follows: the beta-CD solution has the mass concentration of 25 mg/mL, the stirring speed of 800r/min and the stirring temperature of 50 ℃, the camellia bee pollen is stirred for 40min under the conditions to carry out embedding treatment, and the embedding rate of the beta-CD-camellia bee pollen is 82.05 percent.
Example 3 optimization of Camellia bee pollen goat yogurt formula
Adding camellia pollen aqueous extract (added according to the proportion of 1%, 2%, 3%, w/w and different proportions) and beta-CD-camellia pollen aqueous extract embedded matter (added according to the proportion of 3.66%, 7.32%, 10.98%, w/w and different proportions, which is equivalent to that the camellia pollen aqueous extract contains 1%, 2% and 3%) into the goat milk, preparing the goat yogurt by the procedures of blending, homogenizing, sterilizing, fermenting, after-ripening and the like, and comparing the influence of the proportion of the added camellia pollen and the treatment of the beta-CD on the quality and the antioxidant activity of the goat yogurt.
Note: the different upper lower case letters indicate significant differences (P <0.05) in the same line of goat yogurt.
TABLE 1 Effect of beta-CD treatment on the sensory quality of Camellia bee pollen goat yogurt
The effect of β -CD treatment on the sensory quality of camellia bee pollen goat yogurt is shown in table 1. The addition of proper amount of camellia pollen can effectively improve the sensory quality of the goat yogurt, particularly, the color, the flavor and the taste of the product are obviously higher than those of an untreated group after the camellia pollen is treated by beta-CD, and the beta-CD treatment can effectively cover the unpleasant odor and the pigment components of the camellia pollen and endow the product with better sensory quality. According to the total score, the goat yogurt added with the 7.32% beta-CD-camellia pollen aqueous extract has the best sensory quality.
Note: the different upper lower case letters indicate significant differences (P <0.05) in the same line of goat yogurt.
TABLE 2 influence of beta-CD treatment on acidity, lactic acid bacteria count, water holding capacity, texture characteristics and antioxidant activity of camellia bee pollen goat yogurt
The effects of beta-CD treatment on acidity, lactic acid bacteria count, water holding capacity, texture characteristics and antioxidant activity of camellia bee pollen goat yogurt are shown in Table 2. As can be seen from Table 2, the addition of camellia pollen remarkably improves the lactic acid content of the goat pickled with goat, the acidity is continuously increased along with the increase of the addition proportion of the camellia pollen, but the beta-CD treatment can reduce the fermentation acidity of the product to a certain extent; the number of lactobacillus bulgaricus and streptococcus thermophilus in the camellia pollen goat yogurt is obviously reduced, the larger the camellia pollen adding proportion is, the more obvious the reduction of the number of lactobacillus is, and the number of the lactobacillus in the goat yogurt after the camellia pollen water extract is treated by beta-CD is obviously higher than that in an untreated group; compared with a control, the camellia pollen goat yogurt obviously reduces the water holding capacity, the hardness, the consistency, the cohesion and the viscosity index continuously decrease along with the increase of the addition amount of the camellia pollen, and the water holding capacity and the texture index of the beta-CD-camellia pollen goat yogurt obviously improve and are positively correlated with the addition amount of the beta-CD-camellia pollen. The addition of the camellia pollen aqueous extract obviously enhances the oxidation resistance of the goat yogurt and is positively correlated with the addition amount no matter whether the beta-CD is treated or not.
On the whole, the beta-CD treated camellia bee pollen can endow the goat yogurt with better sensory quality, water retention property and texture property, slow down the inhibition on the proliferation of lactic acid bacteria and simultaneously keep stronger acid production speed and antioxidant activity. Therefore, 7.32 percent of beta-CD-camellia bee pollen aqueous extract inclusion is selectively added into the goat milk to prepare the bee pollen goat yogurt.
Example 4 quality and antioxidant Activity changes during refrigeration of beta-CD-Camellia bee pollen goat yogurt
Note: y0 represents control goat yogurt, YB represents goat yogurt added with 7.32% beta-CD-camellia bee pollen aqueous extract embedding substance; the capital letters of different uppercase letters indicate that the goat yogurt has significant difference under the same index in the same column (P < 0.05); the different upper lower case letters indicate significant differences (P <0.05) in the same line of goat yogurt.
TABLE 3 changes in sensory quality, acidity, lactic acid bacteria count, water holding capacity, texture characteristics and antioxidant activity during refrigeration of beta-CD-Camellia bee pollen goat yogurt
Table 3 shows the dynamic changes in product quality and antioxidant activity during refrigeration of beta-CD-camellia bee pollen goat yogurt. In 28 days of refrigeration, the beta-CD-camellia pollen goat yogurt keeps good color, flavor, taste and tissue form, is uniform and creamy yellow, has harmonious smell and fine taste, and whey is not separated out; the acidity is obviously increased along with the extension of the refrigeration time, particularly, the acidity is rapidly increased in the early stage (0-14 d) of the refrigeration and is continuously refrigerated (14-28 d), the increasing amplitude of the acidity is gradually reduced, and the acidity of the beta-CD-camellia pollen goat yogurt is less than 100 after the refrigeration is finished°T; as can be seen from Table 3, the viable count of the control goat yogurt continuously decreased, while the viable count of Lactobacillus bulgaricus and Streptococcus thermophilus in the beta-CD-camellia pollen goat yogurt decreased after increasing, and reached the maximum value after 7 days storage, and the viable count of the two lactic acid bacteria was 47.06X 107And 55.44X 107CFU/mL; continuously refrigerating, the number of lactic acid bacteria is gradually reduced, but the number of lactic acid bacteria in the goat yogurt is far more than 1 × 10 until 28 days of refrigeration6CFU/mL, higher than national standard; the water holding capacity and the texture characteristic change of the beta-CD-camellia pollen goat yogurt during refrigeration show the trend of increasing firstly and then decreasing: at the initial stage of refrigeration (0-7 d), the water holding capacity, hardness, consistency, cohesiveness and viscosity index are obviously increased, and the optimal value is reached at 7 d; in the middle and later period (14-28 d) of refrigeration, the water holding capacity and texture are rapidly reduced. DPPH free radical scavenging ability, FRAP Total antioxidant ability and Fe of beta-CD-Camellia pollen goat yogurt compared to control2+The chelating force is continuously enhanced along with the extension of the refrigeration time, and the increasing amplitudes of the two are more obvious; at the end of refrigeration, DPPH radical scavenging capacity, FRAP Total antioxidant capacity and Fe2+The chelating force is respectively increased by 33.41%, 30.22% and 47.85%.
Therefore, in the refrigeration process, the beta-CD-camellia bee pollen goat yogurt keeps better sensory quality in the shelf life, and the acidity is increased but is less than 100 DEG T; the addition of the beta-CD-camellia bee pollen is beneficial to relieving the reduction of the number of viable bacteria and the deterioration of water holding capacity and texture characteristics in the storage period of the product; the antioxidant activity is obviously improved along with the extension of the refrigeration time. The bee pollen goat yogurt developed after the camellia bee pollen is prepared into the water extract has excellent product quality and antioxidant activity, and is expected to become a novel healthy yogurt product popular with consumers and markets.
Example 5 preparation of bee milk of bee pollen and Camellia Melissa
Taking antibiotic-free fresh goat milk which is qualified by acceptance as a raw material, adding auxiliary materials such as 3% of sucrose, 0.5% of isomaltooligosaccharide, 1% of fructo-oligosaccharide, 0.5% of walnut protein peptide, 0.3% of composite yoghurt stabilizer and the like, stirring, dissolving and mixing, and then homogenizing under high pressure (60-65 ℃, the primary pressure is 20MPa, and the secondary pressure is 5 MPa); and then adding 7.32% of beta-CD-camellia bee pollen aqueous extract embedded matter into the material, performing pasteurization treatment, keeping the sterilization condition at 90-95 ℃ for 5min, quickly cooling to 40-50 ℃ after the sterilization is finished, adding a lactic acid bacteria starter (0.2U/kg milk) into the cooled material liquid, uniformly mixing, fermenting for 5-6 h in a 43 ℃ constant temperature fermentation tank until the fermentation end point is reached, then adding 4% of jujube honey on line, transferring the yoghourt to a 4 ℃ refrigeration house, and performing after-ripening for more than 24h to obtain the honey camellia bee pollen goat yogurt.
The present invention and the technical contents not specifically described in the above embodiments are the same as the prior art.
The present invention is not limited to the above-described embodiments, and the present invention can be implemented with the above-described advantageous effects.
The above embodiments are only specific embodiments disclosed in the present invention, but the scope of the present invention is not limited thereto, and the scope of the present invention disclosed in the present invention should be subject to the scope of the claims.