CN-117337882-B - Preparation method of solidified pure walnut-based yoghourt

Abstract

The invention belongs to the technical field of plant protein modification and processing, and in particular relates to a set pure walnut-based plant yoghourt and a preparation method thereof. The method adopts the protein glutaminase to treat the walnut milk, effectively improves the solubility of the walnut protein, can obviously improve the water holding capacity and whey separation rate of the walnut yoghourt and optimize the texture of the walnut yoghourt, determines the starter suitable for preparing the walnut yoghourt by screening different commercial starter, and improves the acidity and viable count of the walnut yoghourt.

Inventors

• ZHANG HUI
• Yin Xinya
• ZHU LING
• WU GANGCHENG

Assignees

• 江南大学

Dates

Publication Date

20260505

Application Date

20231007

Claims (3)

1. 1. A preparation method of sugar-free solidified pure walnut-based yoghourt is characterized in that peeled walnut kernels and water are mixed and ground to prepare walnut milk, protein glutaminase is utilized to carry out enzymolysis on the walnut milk, and then the walnut milk is subjected to enzyme deactivation, centrifugation, homogenization and sterilization, then starter is inoculated for fermentation, and after-ripening is carried out in a refrigerating manner, so that solidified pure walnut-based yoghourt is obtained, and the enzymolysis method of the walnut milk specifically comprises the following steps: the addition amount E/S of the protein glutaminase is 0.67-U/g to 2.02-U/g, the enzymolysis temperature is 60 ℃ and the time is 15-65 min, the ferment is inoculated according to the addition amount of 0.2-1.0 percent, the starter comprises Lactobacillus bulgaricus, streptococcus thermophilus, lactobacillus bifidus U9, lactobacillus bifidus U2, bifidobacterium animalis A16, bifidobacterium animalis A6S, bifidobacterium animalis A8, bifidobacterium animalis BLA-25, lactobacillus paracasei L9S, lactobacillus paracasei L55, lactobacillus paracasei L56, lactobacillus paracasei L62, lactobacillus paracasei LPA-33, lactobacillus paracasei R14, lactobacillus rhamnosus LL23, lactobacillus rhamnosus T8, lactobacillus reuteri LR09, lactobacillus reuteri LRE-01, lactobacillus reuteri LRE-02, lactobacillus plantarum CR12, lactobacillus plantarum CD71, lactobacillus plantarum LPL-01, lactobacillus plantarum LPL-26, lactobacillus plantarum LPL-606, lactobacillus fermentum CD61, lactobacillus acidophilus RA15, lactobacillus acidophilus CD81, lactobacillus casei CD21, lactobacillus casei CD22, lactobacillus casei CD23, lactobacillus casei W1-1, lactobacillus salivarius LS86, lactobacillus salivarius CD41, lactobacillus BB, lactobacillus salivarius CD44, bifidobacterium CD44, and Bifidobacterium longum CD43, bifidobacterium CD43, bifidobacterium longum and Bifidobacterium, bifidobacterium longum CD11, bifidobacterium breve CD12, bifidobacterium breve BBR-154, bifidobacterium bifidum DB03, bifidobacterium bifidum DB35 and Bifidobacterium adolescentis BQ23, bifidobacterium adolescentis CD65, bifidobacterium adolescentis CD03 and Bifidobacterium adolescentis BBD-66.
2. 2. The method for preparing sugar-free set pure walnut-based yoghourt according to claim 1, wherein the fermentation condition is that the fermentation temperature is 42 ℃ and the fermentation time is 6-8 h.
3. 3. The sugar-free set type pure walnut-based yoghourt is characterized in that the sugar-free set type pure walnut-based yoghourt is prepared by the method of any one of claims 1-2.

Description

Preparation method of solidified pure walnut-based yoghourt Technical Field The invention relates to a set pure walnut-based yoghurt and a preparation method thereof, in particular to a method for preparing a plant-based yoghurt by taking walnuts with long-life fruits and intelligent fruits as raw materials, belonging to the technical field of plant protein modification and processing. Background The market share of the plant yoghourt in recent years is continuously rising, and the plant yoghourt does not contain cholesterol and lactose, so that the requirements of hyperlipoidemia, cow milk allergy, environment-friendly people and animal welfare attentors are met, and the plant yoghourt is beneficial to relieving the global animal husbandry pressure and conforms to the current trend of healthy green food development. Therefore, research into the development of plant-based foods using plant materials instead of animal materials is becoming a hotspot. The walnut kernel is rich in high-quality protein and grease, has complete amino acid types and balanced proportion, contains more monounsaturated fatty acid, polyunsaturated fatty acid, lecithin, vitamins and minerals, and has higher nutritive value. The plant yoghourt in the current market mostly takes soybean, pea, coconut and almond as raw materials, and the pure plant-based set yoghourt taking walnut as raw materials is less common. The walnut is fermented into the yoghourt by lactic acid bacteria, so that the nutrient of the walnut can be reserved, the walnut can be used as a carrier of probiotics to regulate the balance of intestinal flora of a human body, the variety of plant-based foods can be enriched, and the selection of consumers can be widened. At present, the protein content in the walnut accounts for 20% -25%, the gluten content is the most, so that the walnut protein has poor solubility, the application of the walnut protein in food processing is limited, meanwhile, unlike cow milk, the walnut milk lacks lactose, only certain sucrose, glucose and the like, the lactic acid bacteria have weak growth and reproduction capacity in a walnut milk matrix, the acid yield is limited, and the lactic acid bacteria are not easy to survive. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a solidified pure walnut-based yoghourt and a preparation method thereof, and aims to solve the technical problems that in the existing yoghourt preparation process by taking walnuts as raw materials, walnut proteins have poor solubility and cannot form a stable walnut milk system, lactose is lacked in the walnut milk, so that the growth and reproduction capacity of lactic acid bacteria in a walnut milk matrix is weak and a proper walnut fermentation microbial inoculum is lacked. The first technical scheme provided by the invention is a preparation method of a solidified pure walnut-based yoghourt, which comprises the following steps: a method for preparing set-type pure walnut-based yoghourt comprises the steps of carrying out enzymolysis on walnut milk by using protein glutaminase, inactivating enzyme, centrifuging, homogenizing, sterilizing, inoculating a starter for fermentation, refrigerating and after-ripening to obtain the set-type pure walnut-based yoghourt. In certain embodiments, the walnut milk is prepared by mixing peeled walnut kernels with water and pulping. Further, the material-to-water ratio of the peeled walnut kernels to water is 1:3, and the pulping time is 4min (2 min/time). In some embodiments, the enzymolysis method of the walnut milk specifically comprises the following steps of adding 0.1% -0.3% of protein glutaminase (0.67U/g-2.02U/g), and carrying out enzymolysis at 60 ℃ for 15-65 min. In certain embodiments, the enzymatic walnut milk has a deactivation temperature of 95 ℃ for 2 minutes. In certain embodiments, the centrifugation conditions of the walnut milk are 2000rpm for 5 minutes. In certain embodiments, the homogenization conditions of the walnut milk are 200bar, cycled 2 times, and the homogenization temperature is 50-60 ℃. In certain embodiments, the sterilization conditions of the walnut milk are that the sterilization temperature is 65 ℃ and the time is 30min, or that the sterilization temperature is 72 ℃ and the time is 15s. In certain embodiments, the starter is inoculated at an add-on level of 0.2% -1.0% (w/v), the starter including one or more of streptococcus thermophilus, lactobacillus bulgaricus, bifidobacterium lactis, bifidobacterium animalis, bifidobacterium infantis, lactobacillus acidophilus, lactobacillus plantarum, lactobacillus rhamnosus, bifidobacterium animalis, lactobacillus fermentum, lactobacillus salivarius, lactobacillus reuteri, bifidobacterium breve, lactobacillus paracasei, lactobacillus casei, lactococcus lactis, leuconostoc mesenteroides, lactobacillus helveticus, lactobacillus johnsonii, bifidobacterium longum, and bifidobacterium adolescentis. In certain embodiments, the s