阅读说明：本技术 一种低吸湿性银耳多糖微胶囊的制备方法 (Preparation method of low-hygroscopicity tremella polysaccharide microcapsule ) 是由 邵平 宣爽青 吴唯娜 于 2019-09-20 设计创作，主要内容包括：本发明公开了一种银耳多糖微胶囊的制备方法,其包括如下步骤：(1)用去离子水配置3wt％-5wt％的银耳多糖溶液1；(2)往银耳多糖溶液1中添加α-淀粉酶进行活化,得到溶液2；(3)将溶液2进行动态高压微射流处理,而后置于蒸馏水中透析,得到溶液3；(4)配置5wt％-10wt％麦芽糊精水溶液,加入纳米蒙脱土,分散均匀后于80～90℃加热2～3h,离心取上清液,而后加入乳清蛋白,得到溶液4；(5)将溶液4按照体积比1:1的比例添加至溶液3,混合均匀,得到溶液5；(6)将溶液5进行喷雾干燥,得到银耳多糖微囊化粉末。本发明的制备方法能提高银耳多糖微胶囊的产率,降低银耳多糖微胶囊的吸湿性,克服喷雾干燥颗粒贮藏过程中的结块现象。(The invention discloses a preparation method of tremella polysaccharide microcapsules, which comprises the following steps of (1) preparing a tremella polysaccharide solution 1 with the weight percentage of 3-5% by weight by using deionized water, (2) adding α -amylase into the tremella polysaccharide solution 1 for activation to obtain a solution 2, (3) carrying out dynamic high-pressure micro-jet treatment on the solution 2, then placing the solution in distilled water for dialysis to obtain a solution 3, (4) preparing a maltodextrin aqueous solution with the weight percentage of 5-10%, adding nano-montmorillonite, uniformly dispersing, heating at 80-90 ℃ for 2-3 hours, centrifuging to obtain a supernatant, then adding whey protein to obtain a solution 4, (5) adding the solution 4 to the solution 3 according to the volume ratio of 1:1, uniformly mixing to obtain a solution 5, and (6) carrying out spray drying on the solution 5 to obtain tremella polysaccharide microencapsulated powder.)

1. A preparation method of tremella polysaccharide microcapsules comprises the following steps:

(1) weighing the tremella polysaccharide extract, dissolving the tremella polysaccharide extract in deionized water, and preparing into a tremella polysaccharide solution 1 with the weight of 3-5 wt%;

(2) adding α -amylase into the tremella polysaccharide solution 1 for activation to obtain a solution 2;

(3) carrying out dynamic high-pressure microjet treatment on the solution 2, wherein the homogenizing pressure is 80-110MPa, the treatment time is 2-5min, and then putting the solution into distilled water for dialysis to obtain a solution 3;

(4) preparing 5-10 wt% of maltodextrin aqueous solution, adding nano montmorillonite, wherein the feeding ratio of the maltodextrin aqueous solution to the nano montmorillonite is 100 mL: 0.05-0.1g, uniformly dispersing, heating at 80-90 ℃ for 2-3 h, centrifuging to obtain a supernatant, and adding whey protein, wherein the feed ratio of the supernatant to the whey protein is 100 mL: (0.03-0.05) g to give a solution 4;

(5) adding the solution 4 into the solution 3 according to the volume ratio of 1:1, and uniformly mixing to obtain a solution 5;

(6) and (3) carrying out spray drying on the solution 5 to obtain the tremella polysaccharide microencapsulated powder.

2. The method according to claim 1, wherein the α -amylase is added in an amount of 10-20U/g in step (2), and the mixture is activated at 34-38 ℃ for 50-60 minutes.

3. The method of claim 1, wherein: in the step (3), the dialysis conditions are as follows: the cut-off molecular weight of the dialysis membrane is 10 kD-12 kD, and the dialysis membrane is placed in distilled water at 34-38 ℃ for dialysis for 36-48 h.

4. The method of claim 1, wherein: in the step (6), the spray drying conditions are as follows: the air inlet temperature is 160-180 ℃, and the air outlet temperature is 70-80 ℃.

(I) technical field

The invention belongs to the technical field of food processing, and particularly relates to a preparation method of tremella polysaccharide microcapsules

(II) technical background

Tremella fuciformis (Tremella fuciformis) as a traditional delicacy is popular among people due to delicious taste and rich nutrition, and has the reputation of 'crown in bacteria'. Tremella contains abundant Tremella polysaccharides, crude protein, amino acids, crude fiber, vitamins and minerals. The tremella polysaccharide has biological activity in various aspects of resisting tumor, resisting inflammation, improving immunity, delaying senility and the like. The edible fungi polysaccharide is utilized to develop functional food and nutritional preparation products, the added value of the edible fungi is improved, the market of edible fungi products is expanded, and the edible fungi polysaccharide is more and more valued by the domestic and foreign edible fungi industry.

The tremella polysaccharide extracts in the current market are all prepared by water extraction and alcohol precipitation, the purity of the products is low, and terpenoids and saponins are usually contained in addition to polysaccharides, so that microencapsulated powder of the extracts often has some poor characteristics, such as easy moisture absorption and caking, poor liquidity and the like. The main reasons are two aspects, on one hand, the components of the tremella polysaccharide extract are relatively complex and contain a large amount of water-soluble components, so that the critical relative humidity of the tremella polysaccharide microcapsule is low, and the tremella polysaccharide microcapsule can absorb moisture under the condition of low air humidity; on the other hand, the extract contains moisture-absorbing components such as saponin and polysaccharide, and a large number of polar groups such as hydroxyl groups contained in the components are easy to combine with the hydroxyl groups in water molecules, so that the combination effect of the tremella polysaccharide microcapsule and water is enhanced.

The tremella polysaccharide is embedded in the wall material by adopting a spray drying technology, so that air and moisture can be isolated, and active ingredients in the tremella polysaccharide are prevented from being oxidized. However, the tremella polysaccharide extract often contains sticky substances such as saccharides, tannin, mucilage and the like, so that the wall sticking phenomenon is easy to occur in the spray drying process. Wall sticking not only reduces the efficiency of spray drying and reduces yield, but also produces coke breeze and lumps which seriously affect product quality.

Patent CN 103784468A disclosesA process for preparing the sea-buckthorn polyose microcapsules includes such steps as embedding sea-buckthorn polyose in sodium octenyl succinate and β -cyclodextrin, spray drying to obtain said microcapsules, preparing the polyose microcapsules containing more hydroxy groups, and preparing the ganoderma spore polyose from said microcapsules by supercritical CO method₂Fluid extraction of spore oil, water extraction, membrane concentration and spray drying of the extracted remainder to obtain ganoderma spore polysaccharide. The method does not embed ganoderan, and only adopts simple drying treatment, which causes direct contact between ganoderan and air, and influences storage stability.

Disclosure of the invention

The invention aims to solve the technical problem of providing a preparation method of low-hygroscopicity tremella polysaccharide microcapsules, which can improve the yield of the tremella polysaccharide microcapsules, reduce the hygroscopicity of the tremella polysaccharide microcapsules and overcome the caking phenomenon in the storage process of spray-dried particles.

The technical scheme of the invention is specifically explained as follows:

the invention provides a preparation method of tremella polysaccharide microcapsules, which comprises the following steps:

(1) weighing the tremella polysaccharide extract, dissolving the tremella polysaccharide extract in deionized water, and preparing into a tremella polysaccharide solution 1 with the weight of 3-5 wt%;

(2) adding α -amylase into the tremella polysaccharide solution 1 for activation to obtain a solution 2;

(3) carrying out dynamic high-pressure microjet treatment on the solution 2, wherein the homogenizing pressure is 80-110MPa, the treatment time is 2-5min, and then putting the solution into distilled water for dialysis to obtain a solution 3;

(4) preparing 5-10 wt% of maltodextrin aqueous solution, adding nano montmorillonite, wherein the feeding ratio of the maltodextrin aqueous solution to the nano montmorillonite is 100 mL: 0.05-0.1g, uniformly dispersing, heating at 80-90 ℃ for 2-3 h, centrifuging to obtain a supernatant, and adding whey protein, wherein the feed ratio of the supernatant to the whey protein is 100 mL: (0.03-0.05) g to give a solution 4;

(5) adding the solution 4 into the solution 3 according to the volume ratio of 1:1, and uniformly mixing to obtain a solution 5;

(6) and (3) carrying out spray drying on the solution 5 to obtain the tremella polysaccharide microencapsulated powder.

In the invention, the tremella polysaccharide extract, α -amylase, maltodextrin, nano montmorillonite and whey protein can all be commercially available products.

Preferably, in the step (2), the α -amylase is added in an amount of 10-20U/g (g represents the mass of the tremella polysaccharide extract substrate), and is activated at 34-38 ℃ for 50-60 minutes.

Preferably, in step (3), the dialysis conditions are: the cut-off molecular weight of the dialysis membrane is 10 kD-12 kD, and the dialysis membrane is placed in distilled water at 34-38 ℃ for dialysis for 36-48 h.

Preferably, in step (6), the spray drying conditions are: the air inlet temperature is 160-180 ℃, and the air outlet temperature is 70-80 ℃.

The advantages and the beneficial effects of the invention are as follows:

(1) the tremella polysaccharide is treated by combining dynamic high-pressure micro-jet with enzymolysis, so that the viscosity of the tremella polysaccharide solution can be reduced, the fluidity of the solution can be enhanced, and the yield of the tremella polysaccharide microcapsules can be improved.

The tremella polysaccharide is processed by combining dynamic high-pressure micro-jet with enzymolysis, on one hand, amylase is processed by the dynamic high-pressure micro-jet to be unfolded, free sulfydryl content is increased, total sulfydryl content is reduced, α -spiral content is reduced, amylase activity is obviously improved, on the other hand, the opening of tremella polysaccharide molecules is realized by high-speed shearing, vortex and hole action in the dynamic high-pressure micro-jet processing, molecular conformation is changed from ordered to disordered to cause degradation, and the tremella polysaccharide is more easily subjected to mechanical action of the dynamic high-pressure micro-jet and amylase enzymolysis due to the fact that more bonds are exposed after molecular chains are opened due to the existence of the amylase in the solution.

(2) The maltodextrin intercalated with the nano montmorillonite is added into the tremella polysaccharide solution, so that the maltodextrin not only can be used as an auxiliary material to reduce the hygroscopicity of spray-dried particles and the wall sticking rate, but also can be used as an anti-caking agent to prevent caking.

Specifically, the tremella polysaccharide has a softening point temperature in the spray drying process, and exists in a liquid-like jelly form when the drying temperature is higher than the glass transition temperature of the tremella polysaccharide; when the spray drying temperature is lower than the glass transition temperature, the glass state exists as a rigid glass state, so that the wall sticking property of the powder can be effectively reduced by increasing the glass transition temperature. The maltodextrin is used as a common spray drying auxiliary material, can improve the glass transition temperature of a spray drying matrix, and can further increase the glass transition temperature of the matrix by adding montmorillonite in an intercalation mode in the maltodextrin, so that the hygroscopicity of spray drying particles is reduced, and the wall sticking rate is reduced. In addition, the maltodextrin subjected to the nano-montmorillonite intercalation treatment has strong moisture resistance and small viscosity after moisture absorption, and can better overcome the agglomeration phenomenon in the storage process of spray-dried particles.

(IV) detailed description of the preferred embodiment

The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto: