Background
In recent years, the supply of soybean raw materials has been extremely tight. It has become the direction of the industry’s joint efforts to improve the utilization efficiency of soybean raw materials by improving the digestibility and reducing the content of anti-nutritional factors (ANF for short).
In this issue, we introduce the detection methods of three types of ANF in soybean raw materials in detail. And we have collected the content of ANF in different parts, sources, and processing methods of soybean raw materials in the market, so as to provide reference for the reasonable application and to help efficient use of protein resources, reduce costs and increase efficiency in animal husbandry!
Content
1.Evaluation methods of detection
2.Results of Quantitative Detection
Soybean by different parts
【Test Results】
PS: The same source of soybeans are divided into soybean curd, peeled soybean, and whole soybean to determine ANF. This is for reference only due to its limited samples for detection.
【Results Analysis】
Content of peeled soybean and soybean curd:
three types of antigen proteins content: soybean curd＜whole soybean＜peeled soybean
It indicates that antigen protein exists in cotyledon of soybean.
Mix of peeled soybean and soybean curd:
three types of antigen proteins content: 43 soybean meal＜46 soybean meal
It shows that the more soybean curd is added, the lower the content of the antigen protein.
Soybean of different origins
【Test Results】
PS: Soybeans from different origins are measured by same process to produce soybean meal and then determine antigen protein. This is for reference only due to its limited samples for detection.
【Results Analysis】
This 3 kinds of Antigen proteins in Americano soybean is lower than Brazillian, which may be related to the differences in varieties of origins.
Soybean of different processing methods
【Test Results】
【Results Analysis】
Soybean meal: the process of heating and soaking oil degenerates the structure of antigen protein. (removal rate: 10-20%)
Puffed soybean meal: high pressure of extruding process degenerates protein structure and passivates antigen protein. (removal rate: 40-60%)
Puffed soybean: high temperature and pressure and mechanical shear in the process passivate antigen protein. (removal rate: 50-70%)
Fermented soybean meal: microbial fermentation produces enzymes that partially degrade antigen proteins. (removal rate: 30-50%)
Soy protein concentrate: process of washing with alcohol denature and inactivate the structure of the antigen protein. (removal rate: 90%↑)
Enzymatic hydrolysate of soybean protein: protease open and degrade the complex spatial structure of antigen proteins to reduce allergenicity. (removal rate: 90%↑)
Soybean of different manufacturer
【Test Results】
【Results Analysis】
Soybean meal: The production process to produce soybean meal is relatively stable, thus the fluctuation of antigen protein content is small.
Puffed soybean: The process parameters of high temperature and pressure in the puffing process vary greatly, thus the content of antigen proteins fluctuate.
Fermented soybean meal: bacteria strains and conditions of fermentation vary greatly, so the content of antigen proteins fluctuates greatly.
Enzymatic hydrolysate of soybean protein: Protease degrades the spatial structure of antigen proteins, so the content of antigen proteins are low. The fluctuation is small.
3.Results of Qualitative Detection
【Test Results】
【Results Analysis】
SDS-PAGE polyacrylamide electrophoresis analysis shows the target band of soybean antigen protein. If there is any sign, it indicates the presence of antigen protein; if not, the antigen protein are cleared.
There’re obvious differences of the target bands among different protein materials: soybean meal, puffed soybean, and soy protein concentrate have clear antigen protein bands, which indicate the existing of antigen proteins. Different sources of antigenic protein bands in fermented soybean meal are degraded to a certain extent. Different sources of antigen protein bands in enzymatic hydrolysate of soybean protein are basically eliminated.