Key points on the determination of protein Solubility of Soybean meal

Recently measured the protein solubility PS of soybean meal, how to find that the results are on the low side, how do you detect it? What matters should be paid attention to in the testing process, and what is the allowable error in the determination of the solubility of this protein? -- that's because the soybean meal itself is bad, isn't it, the reagent is out of date, the concentration is accurate, and whether the quantity is correct? other things don't seem to matter. There is also a sampling problem. Maybe the raw material itself is so low. Do you have a test with other companies or for inspection? which master can post a test method for protein solubility? I'm not an expert, but I can post one for you! Method for determination of protein solubility in feed 1. Scope of application: this standard provides a method for the determination of protein solubility in feed. This standard is applicable to the degree of heating treatment of soybean meal. two。 Citation standard: feed quality inspection 3. Method principle: the antitrypsin activity method can be used to determine the heating transition soybean meal, but it is not widely used because it is time-consuming and expensive. Therefore, the chemical index of urease activity is often used, but urease activity can only be used as an evaluation index of heating to a suitable degree, but it has no significance for heating transitional meal. The urease value can not reflect the quality of soybean meal subjected to severe heat treatment. Rinehart found that the method of determining protein solubility in 0.2%KOH solution to evaluate the quality of soybean meal can overcome the shortcomings in the evaluation of urease activity mentioned above. Some feed companies in North America and the poultry industry in Brazil have included protein solubility (PS) as one of the quality control indicators. The PS of raw bean cake and meal can reach 100%, but with the extension of heat treatment time, the PS value decreases, even if the severe overheating treatment, the PS value is not close to zero. The results showed that the solubility of protein more closely reflected the relationship between overcooked soybean cake, meal and chicken performance. It is further proposed that when PS > 85%, it is over-birth; PS