TWI475962B - Method for preparing soybean peptide-calcium chelate - Google Patents

Description

Method for preparing soybean peptide-calcium chelate

The present invention relates to a method for preparing a soybean peptide, and particularly relates to a method for preparing a soybean peptide-calcium chelate.

Soy has a long history of consumption. Soybeans have high nutritional value, are rich in protein and fiber, and have many functional ingredients to maintain good health. Phytosterols can lower cholesterol, and isoflavones relieve women's menopausal symptoms, vitamin E and saponin. Provides antioxidant function. For vegetarians, it is a good food choice for getting nutrition. In recent years, Western society has also vigorously promoted soy products, and the health image of soybeans is increasing day by day.

Soymilk is a very common food in Chinese daily life, but compared with milk, the calcium content of soy milk is obviously low. According to the US Department of Agriculture, the calcium content of milk is 113 mg/100 g, and the calcium content of soy milk is only 39 mg/100. Gram (USDA, 2008). If the home-made homemade soymilk in the traditional market or breakfast store may have increased doubts about water, the calcium content will be lower and the calcium obtained will be more limited. Therefore, special attention should be paid to the demand for calcium intake by the population that regularly consume soy milk products.

Calcium plays many important roles in human physiological and biochemical functions, including the formation of major bone elements, blood coagulation, muscle contraction, acid-base balance, maintenance of cell membrane permeability, blood pressure regulation, participation in many enzyme reactions, etc., is an indispensable nutrient. . The growth and development of the human body continues to absorb calcium and store the "bone bones" until the peak reaches 35 to 45 years old. Then, as the age increases, the bone calcium gradually loses and the female loses faster after menopause (Bronner. et al., 1999). ). Therefore, people must pay attention to calcium intake from time to time, because calcium must be obtained from daily diet and cannot be manufactured by itself. According to the National Nutrition Survey of China, the average intake of males in Taiwan is 520 mg, and the average female is 542 mg. If measured by American RDA (1,200 mg) or RDI (1,300 mg), it is severely under-acquired. Based on the general lack of calcium in the Chinese population, the Department of Health's revised “National Dietary Nutrient Reference Intake” revised in 2002 significantly revised the intake of calcium from 600 mg per day for adults to 800 to 1000 mg (http:/ /www.doh.gov.tw). Moreover, in recent years, the frequency of fractures in the elderly has increased, and the intake of calcium is insufficient, leading to a considerable correlation between bone loosening. According to a survey conducted by the Department of Health, one in nine people in Taiwan is suffering from osteoporosis, and one in every four people (http://www.doh.gov.tw) . Therefore, the primary task of improving bone health is to get enough calcium.

The more common sources of calcium are provided by dairy products, but many people have lactose intolerance. In addition, in Taiwan, the per capita consumption of dairy products is much lower than in Western countries, which is also the reason for reducing the total calcium intake.

Studies have found that casein in dairy products, after decomposition by proteolytic enzymes in the stomach and intestines, produces a peptide component that inhibits the precipitation of calcium ions in an alkaline environment, called Caseinophosphopeptide (CPP). ). Calcium ion absorption in the small intestine, except for a small part (15-20% by weight) in the duodenum part of the front end requires the active transport of vitamin D, most of the calcium ions enter the human circulatory system, relying on the jejunum and ileum Passive transport (60-65% by weight) (Bronner, F. 1998. Calcium Absorption-A Paradigm for Mineral Absorption J. Nutr. 128: 917-920; Bronner, F. and Pansu, D. 1999. Nutritional Aspects of Calcium Absorption. J. Nutr. 129: 9-12). Since the pH of the posterior segment of the small intestine is weakly alkaline, calcium can be maintained in the presence of a CPP peptide fragment containing the SerP-SerP-SerP-Glu-Glu sequence. The dissolved state of ions and passive transport through the intestinal cell space (Ferraretto, A.. Signorile, A Gravaghi, C. Fiorilli, A. and Tettamanti, G. 2001. Casein Phosphopeptides Influence Calcium Uptake by Cultured Human Intestinal HT-29 Tumor Cells J. Nutr. 131: 1655-1661). In order to avoid the occurrence of diseases such as osteoporosis caused by the lack of calcium, in addition to increasing calcium intake, it is also a good method to increase the absorption rate of calcium. However, patients with lactose intolerance are not suitable for using casein in dairy products to promote calcium absorption.

Therefore, adding soy milk products to calcium sources has become an important business opportunity for product development. On the technical level, in the production of calcium soymilk, the addition of calcium has processing obstacles, because the soy protein in the soy milk causes hydrophobic aggregation due to the added calcium ions, thereby precipitating the soy protein. To solve such processing problems, it is a common method to add a chelating agent to form a stable structure with calcium ions and to reduce soy protein precipitation. For example, sodium hexametaphosphate, sodium citrate, sodium hydrogen phosphate, etc. are commonly used soy chemical additives to improve product stability (Pathomrungsiyounggul, et al., 2010). With increased health awareness, the use of additives in the food processing sector requires special attention. Unnecessary chemical additives should be avoided, and natural ingredients or additives replaced by them are more reassuring considerations.

In the past, some scholars have proposed to produce a single calcium-promoting peptide by chemical synthesis, but the cost is quite high and it is difficult to use it practically (Galzigna, L., Domergue, N., Previero, A. 1998. A synthetic calcium- Chelating L-glutamyl-L-serine phosphate (Glu-Ser. P) enhances calcium absorption in the rat. J Pept Res. 52(1): 15-18). In addition, some scholars have proposed to use chemical additives as a chelating agent or stabilizer to achieve the purpose of soymilk to strengthen calcium (Pathomrungsiyounggul, P., Lewis, MJ and Grandison, AS 2010. Effects of calcium-chelating agents and pasteurization on certain properties of calcium -fortified soy milk. Food Chem. 118:808-814; Luhadiya, APC, Yang, DK, Heisey, MT 2006. Calcium fortified beverages. US Patent 6994877 B2), although chemical additives still have safety considerations, no more than natural A chelating agent, and the final pH value of the product of Luhadiya et al. is 8.25, which is more difficult to drink. In addition, some scholars have proposed the use of the chemical additive sodium citrate as a chelating agent to make calcium soy milk (Mino and Araki, 2005). The mainland patent CN 101161114 B discloses the use of commercial proteolytic enzymes to hydrolyze soy protein to produce a soybean peptide to produce a soybean peptide-calcium mixture, but at a higher cost.

In summary, there is a need for a low manufacturing cost, and can increase the absorption rate of calcium for patients with lactose intolerance, in line with practical and safe safety concerns.

The invention provides a method for preparing a soybean peptide-calcium chelate, the method comprising the steps of: mixing a raw material containing soy protein with water to form a mixture having a water content of about 45%-65% by weight; The inoculum is inoculated into the above mixture to obtain a culture, wherein the above-mentioned bacterium group includes: Aspergillus oryzae, Aspergillus sojae, or a mixture thereof, and the inoculum of the above-mentioned sputum group accounts for about 0.006% by weight of the above-mentioned soybean protein material. -0.05%; solid-fermenting the above culture to obtain a fermentation product, wherein the conditions of the solid-state fermentation include: a relative humidity of about 85%-95% and a fermentation temperature of about 23-35 degrees Celsius; hydrolyzing the fermentation product. The reaction obtains a soybean hydrolyzate; the soybean hydrolyzate is sequentially subjected to clarification treatment and solid-liquid separation to obtain a soybean clarified hydrolyzate; and the soybean clarification hydrolyzate is directly added with calcium ion mixture, wherein the soybean peptide and calcium ion are mixed. The molar ratio is 2:1~0.5:1, and the water content is adjusted to 60~65% by weight, and the pH is between 6.5 and 7, to obtain a soybean peptide-calcium chelate Liquid of the compound.

The invention further provides a method for preparing a soybean peptide-calcium chelate, the method comprising: mixing a raw material containing soy protein with water to form a mixture having a water content of about 45%-65% by weight; The inoculum is inoculated to the above mixture to obtain a culture, wherein the above-mentioned bacterium group includes: Aspergillus oryzae, Aspergillus sojae, or a mixture thereof, and the inoculum of the above-mentioned sputum group accounts for about 0.006 by weight of the above-mentioned soybean protein material. %-0.05%; solid-fermenting the above culture to obtain a fermentation product, wherein the conditions of the solid-state fermentation include: relative humidity of about 85%-95% and fermentation temperature of about 23-35 degrees Celsius; Hydrolyzing to obtain a soybean hydrolyzate; the soybean hydrolyzate is sequentially clarified and solid-liquid separated to obtain a soybean clarified hydrolyzate; the soybean clarified hydrolyzate is uniformly mixed with soybean oil and lecithin, wherein the soybean oil is uniformly mixed The concentration is 2 to 8% by weight of the solids of the soybean hydrolysate, and the concentration of the lecithin is 0.01 to 0.05% by weight of the soybean oil to obtain a mixture; The mixture is dried to obtain a soybean peptide powder; the soybean peptide powder and calcium ions are dissolved in water, wherein the ratio of the molar ratio of the soybean peptide to the calcium ion in the soybean peptide powder is 2:1 to 0.5: 1, and adjust the water content to 60-65% by weight, and the pH value is between 6.5 and 7, to obtain a liquid containing the soybean peptide-calcium chelate.

The present invention further provides a method for preparing calcium-fortified soybean milk, which comprises adding the aforementioned soybean peptide-calcium chelate compound to soybean milk.

The invention also provides a calcium-fortified soybean milk obtained by the method for preparing the calcium-enhanced soybean milk, wherein the calcium-enhanced soybean milk has a calcium content of more than 40 mg/100 ml.

The above and other objects, features and advantages of the present invention will become more apparent and understood.

The invention provides a preparation method of soybean peptide-calcium chelate. In one embodiment, the soybean powder is subjected to solid state fermentation decomposition by sputum, and then subjected to a hydrolysis reaction, followed by a clarification step to obtain a clarified hydrolyzate, and then directly added calcium chloride to the soybean clarified hydrolyzate, and The water content and pH are adjusted to obtain a liquid containing the soybean peptide-calcium chelate. In another embodiment, the soybean clarification hydrolyzate may be subjected to a milling step, and the soybean peptide powder and the calcium ion may be mixed with water and stirred to dissolve, and the pH value is adjusted to prepare a soybean-containing peptide-calcium chelate. The peptide product of the substance.

The present invention utilizes soybean to produce a soybean peptide, the principle of which is to use a mixture of Aspergillus oryzae, Aspergillus sojae, or a mixture of the above species to treat a soybean protein-containing raw material for solid-state fermentation, wherein the soybean protein is Sources include, but are not limited to, soy flour, defatted soy flour, defatted soy flakes, soy protein isolate, soy meal, bean cake, or combinations thereof. In one embodiment, the inoculum inoculation amount is from about 0.006% to 0.05%, preferably from about 0.008% to 0.02%, more preferably about 0.013%, based on the total weight of the raw materials. In the above solid state fermentation, various buffers can be used, for example: citric acid-sodium citrate, acetic acid-sodium acetate, K ₂ HPO ₄ -KH ₂ PO ₄ , Na ₂ HPO ₄ -NaH ₂ PO ₄ , boric acid-hydrogen peroxide Sodium, trishydroxymethylmethylaminopropanesulfonic acid, N,N-bis(2-hydroxyethyl)glycine, trishydroxymethylaminomethane, N-tris-(hydroxymethyl)methylaminoacetic acid, 4- (2-hydroxyethyl)-1-piperazineethanesulfonic acid hemi-sodium salt, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, 3-(N-morpholine)ethanesulfonic acid Piperazine-N,N'-bis(2-ethanesulfonic acid), sodium citrate citrate, 2-morpholineethanesulfonic acid, etc., regulate the water required for solid-state fermentation, and the required water accounts for the raw materials. The total weight of the mixture with water is from about 45% to about 65%, preferably from about 50% to about 60%, more preferably about 55%. In one embodiment, the solid state fermentation may be performed at a pH of about 5 to 7; a relative humidity of about 85% to 95%; a fermentation temperature of about 23 to 35 degrees Celsius; and a fermentation time of about 2 to 5 days. .

The above fermentation product is then subjected to a hydrolysis reaction to obtain a soybean hydrolyzate. In one embodiment, the step of performing the hydrolysis reaction comprises: mixing the fermentation product with water at a weight ratio of about 1:1 to 1:3, preferably about 1:2; and the hydrolysis time is about 3-24. The hour is preferably about 6 hours; the hydrolysis temperature is between about 30 and 65 degrees Celsius, preferably about 45 degrees Celsius. Thereafter, the reaction temperature is raised to about 90-95 degrees Celsius to inhibit the activity of the enzyme.

Thereafter, the soybean hydrolyzate is subjected to clarification treatment such as solid-liquid separation. For example, a press can be used to separate the solid and liquid by hydraulic pressure. The liquid is then heated at 90 ° C for 10 minutes to precipitate, and then the precipitate is removed by a high-speed centrifuge. Finally, the hydrolyzate is filtered using a plate and frame filter press or a microfiltration membrane, and the peptide containing the above-mentioned calcium-absorbing absorption is collected. Hydrolyzate.

Then, the obtained hydrolyzate is chelated with calcium ions, and the obtained hydrolyzate may be subjected to a milling step and then chelated with calcium ions to prepare a peptide product of various forms of soybean peptide-calcium chelate. It will be appreciated that those skilled in the art can also use any other suitable solid-liquid separation means, as well as other suitable filtration means.

In one embodiment, the step of chelating the hydrolyzate with calcium ions may include: directly adding calcium ions to the soybean clarified hydrolysate, and the source of the calcium ions may be selected from the group consisting of, for example, It is not limited to: inorganic calcium, such as calcium chloride, calcium carbonate, calcium phosphate, and organic calcium, such as calcium lactate, calcium citrate, calcium gluconate, and combinations thereof, wherein a mixture of a soybean peptide and a calcium ion is used. The ratio is 2:1~0.5:1, preferably 1:1, and the water content is adjusted to 60~65%, preferably 65%, and the pH is between 6.5 and 7, preferably 6.7, to obtain a soybean containing win. A liquid of a peptide-calcium chelate.

In another embodiment, the step of chelating the hydrolyzate with calcium ions may include: treating the clarified soybean hydrolyzate with a vacuum decompression concentrator to obtain a high concentration soybean hydrolyzate (solid content 40-60% by weight) Percentage), adding soybean oil to 2-8%, preferably about 5% by weight (100% by weight of soy hydrolysate solids) and lecithin from 0.01% to 0.05%, optimally about 0.02% by weight ( Soybean oil weighs 100% by weight), thoroughly mixed using an ultra-high speed homogenizer, followed by drying with a spray dryer under the conditions of an inlet temperature of 145-160 ° C, preferably 150-155 ° C, and an outlet temperature of 85-110 ° C. Preferably, the temperature is 35-105 ° C, the rotation speed is 35-40 Hz, preferably 40 Hz, to obtain a soybean peptide powder, and then the soybean peptide powder and the calcium ion are added to the water at a temperature of 25-50 ° C, preferably at room temperature, and stirred and dissolved. The source of the above calcium ions may be selected from the group consisting of, but not limited to, inorganic calcium such as calcium chloride, calcium carbonate, calcium phosphate, and organic calcium such as calcium lactate, calcium citrate, calcium gluconate, And a combination of the above, wherein the peptide chelate The ratio of the molar ratio of the soybean peptide to the calcium ion is 2:1 to 0.5:1, preferably 1:1, and the water content is adjusted to 60-65%, preferably 65%, and the pH value is adjusted to 6.5. ~7, preferably pH 6.7, is the peptide product of the soybean peptide-calcium chelate.

In one embodiment, the preparation of the calcium fortified soymilk of the present invention may comprise: adding different amounts of the soy peptide-calcium chelate compound from the above process to the commercial soymilk for mixing. The calcium-fortified soymilk obtained by the preparation method of the present invention may have a calcium content of more than about 40 mg/100 ml, preferably about 40 to 90 mg/100 ml. In the embodiment of the commercially available soybean milk having a calcium content of 40 mg/100 ml, when the calcium content is 60 mg/100 ml of soybean milk, the soy milk is easily thickened, and the soy protein is agglomerated by calcium ions, and the higher the concentration, the more remarkable the aggregation phenomenon is, and It is easy to form a layer of protein precipitate. Preferably, the calcium content is 50 mg/100 ml or less, and the appearance and taste are good, and the calcium content of the calcium-fortified soymilk product obtained at this time is about 90 mg/100 ml, which is close to the calcium content of the milk (about 113 mg/100 ml). ).

The soybean protein raw material used in the preparation method of the calcium-enhanced soybean milk provided by the invention is easy to obtain and low in cost, and can increase the absorption rate of calcium by the patient suffering from lactose intolerance, and is a soy milk drink which is practical and has no safety concerns. It can provide consumers with higher than normal soy milk, even close to the calcium content of milk.

[Examples] Example 1. Production of calcium absorption soy peptides

Using defatted soybean meal as raw material, inoculate Aspergillus sojae, wherein the inoculum inoculum is 0.013% of the total weight of the soybean raw material, and the water is adjusted by a buffer of 0.25% by weight of CH ₃ COONa/0.25% HNaSO ₃ and pH=5.8. Up to 55%, cultured in an environment of 25 to 30 ° C and a relative humidity of 95% or more for 2 days.

Then, the hydrolysis reaction is carried out, and the soybean meal is mixed with water, wherein the ratio of soybean meal to water is 1:2, the hydrolysis time is 6 hours, the hydrolysis temperature is 45 ° C, and the temperature is further increased to 90-95 ° C for 10 minutes to inhibit the enzyme. active.

Next, the clarification treatment of the hydrolyzate is carried out, and the soybean hydrolyzate is first placed in a filter bag using a press, and laid flat in a press tank to separate the solid and liquid by oil pressure. The liquid was then heated to a temperature of 90 ° C for 10 minutes, and the precipitate was removed by a telecentric high-speed centrifuge (16,000 rpm, Taichung, manufactured by Quantai Co., Ltd.), and finally filtered using a plate and frame filter press (Seitz Orion, made in Germany) or The hydrolyzate was filtered using a microfiltration membrane (0.3 μm) to obtain a clarified soybean hydrolyzate.

Example 2. Effect of Soy Hydrolysate on Inhibition of Calcium Carbonate Precipitation

According to Jin et al. (J. Agnc. Food Chem. 2000) calcium carbonate crystallization experiment slightly modified, 1 ml sample was mixed with 1 ml concentration of 40 mM calcium chloride and 1.2 ml of distilled water, then added 0.8 ml concentration of 40 mM carbonic acid The reaction was carried out for 1 hour with sodium hydrogen and maintained at pH = 8.5 by titration with 0.1 N sodium hydroxide. The mixed solution at the end of the reaction was centrifuged (centrifugal force: 2000 g), and the supernatant was taken to measure the calcium concentration using the calcium measuring reagent group (product of Taiwan Merck), which is the soluble calcium content.

In the experiment for inhibiting calcium carbonate crystallization, the soy protein hydrolyzate obtained in Example 1 has an inhibitory effect on calcium carbonate crystals, and the effect is evaluated as the minimum sample concentration for completely inhibiting calcium carbonate crystals under alkaline conditions (pH=8.5). If calcium carbonate precipitates, the calcium content of the supernatant decreases; otherwise, the calcium content of the supernatant does not change. Fig. 1 is a graph showing the effect of inhibiting calcium carbonate crystallization in soybean protein hydrolysate compared with casein phosphopeptide, and the results showed that the minimum inhibitory concentration of casein phosphopeptide protein (CPP) which promotes calcium absorption was 1.76 x 10 ^-4 %. The protein of the soy protein hydrolyzate of the present invention has a minimum inhibitory concentration of 2.16 x 10 ^-3 %.

Example 3. Effect of inhibition of soybean hydrolysate

In this example, different protein source materials were selected for comparison, and 1 ml sample was mixed with 1 ml of 40 mM calcium chloride and 1.2 ml of distilled water, and then reacted for 1 hour by adding 0.8 ml of 40 mM sodium hydrogencarbonate. The pH was maintained at 8.5 using 0.1 N sodium hydroxide titration. The reaction mixture was centrifuged (centrifugal force: 2000 g), and the supernatant was used to measure the calcium concentration using the calcium measuring reagent group (product of Taiwan Merck), and under the alkaline condition (pH=8.5), the carbonic acid was completely inhibited. The lowest sample concentration of calcium crystallization is used as an evaluation criterion for soluble calcium content.

Figure 2 is the effect of different protein source materials on the inhibition of calcium carbonate crystallization. Among them, free amino acids such as monosodium glutamate (MSG) and glycine have poor inhibitory effects; followed by proteins such as isolated soy protein (ISP), casein, and chicken of essence (essence of chicken). The commercially available product, which is a chicken protein extract), is superior to the first two types in inhibiting the precipitation of calcium carbonate; and the soy hydrolysate of the present invention is the best. It can be seen that a single free amino acid or a complete protein is not chelated with calcium ions as in the case of protein hydrolysates. After hydrolysis of proteins to different extents, they have a better effect of inhibiting calcium precipitation. Therefore, the protein material of the peptide type, such as chicken essence, and the method for decomposing soy protein hydrolyzate by using the bacteriocin enzyme are all good calcium precipitation precipitants.

Example 4. Effect of calcium-promoting peptide on calcium absorption in animals

The experimental method is similar to that of Lai Ai Ji (The Journal of the Taiwan Nutrition Society, Vol. 21, No. 2, 1996), but with minor modifications, adult female rats (Bltw: SD; purchased from Lesco Biotech Co., Ltd.) are kept in separate countries. In the metabolic cage, the room temperature was maintained at 23±2°C, and the light was irradiated for 12 hours. After the food was removed for one day, the soybean protein isolate was added as the control group or the calcium-promoting peptide was used as the experimental group. The number is 10, the animals are fed ad libitum, the feces are collected daily, the feed is taken after 6 days, the total amount of food is taken, and after waiting for one day to exclude the feed, the calcium content in the excreted feces is collected and analyzed. . Calcium analysis is carried out by nitric acid and then measured by atomic absorption spectrometer.

The total intake of calcium is estimated by the amount of feed eaten by the amount of calcium in the feed. The absorption rate of calcium (total intake - calcium content in feces) / total intake.

Figure 3 shows the calcium absorption rate of mice fed with calcium-promoting peptide and soy protein. Comparing the absorption rate of soy protein or calcium-promoting peptide, it was found that the absorption rate of calcium-enhancing peptide was significantly higher than that of the larger soybean protein, and the mean value was ±95% confidence interval, and there was a significant difference between the two (p<0.05).

Table 1. Soy protein isolate (control group) and calcium-enhancing peptide (experimental group) feed formulation (quantity of each component per gram of feed, in grams).

Example 5. Preparation method of soybean peptide powder

The clear soybean hydrolyzate obtained in Example 1 was treated with a vacuum decompression concentrator to obtain a high concentration soybean hydrolyzate (solid content 40%), soybean oil was added as 5% of the total weight of the soybean hydrolysate solid, and lecithin was large. 0.02% of the total weight of soybean oil was thoroughly mixed using an ultra-high-speed homogenizer, followed by drying with a spray dryer under the conditions of an inlet temperature of 150 ° C, an outlet temperature of 90 ° C, and a rotational speed of 40 Hz to prepare a soybean peptide powder.

Example 6. Preparation of calcium fortified soy milk

The soybean peptide powder obtained in Example 5 was 39.42 g and 9 g of calcium chloride and 90 g of water were mixed and stirred at room temperature, and the ratio of the peptide chelated calcium formed by the soybean peptide powder, calcium chloride and water was 4.38. : 1:10 (weight ratio), adjust the pH value of pH 6.7, and then add different amounts of chelated calcium solution to the commercially available soybean milk (sugar-free soy milk, manufactured by Yimei Co., Ltd., Taiwan) and mix and stir. The sensory evaluation and calcium content of the final product are shown in the table (Table 1), and the calcium concentration was measured using the calcium measuring reagent group (product of Taiwan Merck). When the calcium content of 60mg/100ml soy milk is added, it is obvious that the soy milk becomes thick, and the soy protein is agglomerated by calcium ions. The higher the concentration, the more remarkable the agglomeration phenomenon, and the protein precipitates are layered. The best product quality is the addition of calcium content below 50mg/100ml, their appearance and taste are good, the highest calcium content of calcium-fortified soymilk products is close to milk (90mg/100ml; milk calcium content is about 113 mg/100ml).

Table 1. Sensory evaluation of different calcium additions to soymilk

。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 A number of changes and modifications may be made, and the scope of the invention is defined by the scope of the appended claims.

Fig. 1 is a graph showing the effect of inhibiting the crystallization of calcium carbonate in comparison with the casein phosphopeptide by the soy protein hydrolyzate.

Figure 2 is the effect of different protein source materials on the inhibition of calcium carbonate crystallization.

Figure 3 shows the calcium absorption rate of the rats fed the calcium-promoting peptide and the soy protein feed, with a mean ±95% confidence interval, with significant differences between the two (p < 0.05).

Claims (12)

A method for preparing a soybean peptide-calcium chelate, the method comprising: mixing a raw material containing soy protein with water to form a mixture having a water content of about 45% to 65% by weight; Inoculation with the mixture to obtain a culture, wherein the bacillus flora comprises: Aspergillus oryzae , Aspergillus sojae , or a mixture thereof, and the inoculation amount of the sputum bacteria is about 0.006%-0.05% by weight of the soybean protein material. The culture is subjected to solid state fermentation to obtain a fermentation product, wherein the conditions of the solid state fermentation include: a relative humidity of about 85%-95% and a fermentation temperature of about 23 to 35 degrees Celsius; and the fermentation product is hydrolyzed to obtain a a soybean hydrolyzate; the soybean hydrolyzate is sequentially subjected to clarification treatment and solid-liquid separation to obtain a soybean clarified hydrolyzate; and the soybean clarification hydrolyzate is directly added with calcium ion mixture, wherein the soybean peptide and the calcium ion are in a molar state. The ratio is 2:1 to 0.5:1, and the water content is adjusted to 60-65% by weight, and the pH is between 6.5 and 7, to obtain a liquid containing the soybean peptide-calcium chelate. A method for preparing a soybean peptide-calcium chelate, the method comprising: mixing a raw material containing soy protein with water to form a mixture having a water content of about 45% to 65% by weight; Inoculation with the mixture to obtain a culture, wherein the bacillus flora comprises: Aspergillus oryzae , Aspergillus sojae , or a mixture thereof, and the inoculation amount of the sputum bacteria is about 0.006%-0.05% by weight of the soybean protein material. The culture is subjected to solid state fermentation to obtain a fermentation product, wherein the conditions of the solid state fermentation include: a relative humidity of about 85%-95% and a fermentation temperature of about 23 to 35 degrees Celsius; and the fermentation product is hydrolyzed to obtain a Soybean hydrolyzate; the soybean hydrolyzate is sequentially clarified and solid-liquid separated to obtain a soybean clarified hydrolyzate; the soybean clarified hydrolysate is uniformly mixed with soybean oil and lecithin, wherein the concentration of soybean oil is soybean hydrolysis 2 to 8% by weight of the liquid solids, and the concentration of lecithin is 0.01 to 0.05% by weight of the soybean oil to obtain a mixture; the mixture is dried to obtain a soybean a peptide powder; the soybean peptide powder and calcium ions are dissolved in water, wherein the ratio of the molar ratio of the soybean peptide to the calcium ion in the soybean peptide powder is 2:1 to 0.5:1, and the water content is adjusted to 60 to 65% by weight, and a pH of 6.5 to 7, to obtain a liquid containing a soybean peptide-calcium chelate. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the source of the calcium ion is selected from the group consisting of organic calcium, inorganic calcium, and a combination thereof, wherein the inorganic calcium is selected A group consisting of calcium chloride, calcium carbonate, calcium phosphate, and combinations thereof, selected from the group consisting of calcium lactate, calcium citrate, calcium gluconate, and the like. combination. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the soybean protein-containing material comprises soybean powder, defatted soybean powder, defatted soybean flakes, soy protein isolate, soybean meal, Bean cake, or a combination of the above. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the solid state fermentation is carried out at a pH of about 5 to 7. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the solid fermentation time is about 2 to 5 days. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein in the hydrolysis reaction, the weight ratio of the fermentation product to water is about 1:1 to 1:3. The method for producing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the hydrolysis reaction has a hydrolysis time of about 3 to 24 hours. The method for producing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein the hydrolysis reaction has a hydrolysis temperature of about 30 to 65 degrees Celsius. The method for preparing a soybean peptide-calcium chelate compound according to claim 1 or 2, wherein after the hydrolysis reaction is completed, the reaction temperature is further increased to about 90-95 degrees Celsius to inhibit the enzyme activity. A method for preparing a calcium-enriched soybean milk, which comprises adding the soybean peptide-calcium chelate compound according to any one of claims 1 to 2 to the soybean milk, wherein the calcium content of the calcium-fortified soybean milk is between 40~90mg/100ml. A calcium-enhanced soymilk obtained by the method for preparing calcium-fortified soymilk according to claim 11 wherein the calcium-enriched soymilk has a calcium content of 40 to 90 mg/100 ml.