| Abstract: |
The experiments were carried out on two varieties of soybean namely: clark and crawford, soaked in mixed salt solution for 12 hours and cooked by atmospheric pressure l000C/25 minutes or by autoclaving at 120°C/10 minutes. Thereafter, two soybean protein products namely flour and concentate were prepared.The data can be summarized as follows: _ Gross chemical composition:The protein content of investigated samples showed higher levels for raw protein concentrate than that of corresponding raw soybean flour. It could be noticed that heated samples slightly increased in b6th protein and ash contents._ Minerals content: Resul~s showed that potassium, phosphorus, calcium, and iron were main elements in both clark and crawford soybean flour. In addition to, soybean protein concentr¬ate samples had significant amount of calcium,iron, phosphorus, copper, zinc and manganes0• It is clear that soaking and heat treatment affected potassium content, since it decreased considerably. - Amino acids content:The data revealed that the soybean flour of the two varieties mir,ht be considered as rich source of lysine, phenylalanine, and tryptophan; while, they were poor in methionine, as well as raw soy concentra~e samples. Flours from soaked and heated samples showed an increase in the levels of sulfur containing amino acids as well as soybean protein concentrates.- Protein fractions: Electrophoretic analysis showed that all protein fractions in raw soybean flour of the two varieties were foucused in the pH range of 3.5 and 9.4 which were con-centrated between 5.3-7.3. In this region more minor bands were observed in electrophoretic pattern of raw clark flour when compared with that of raw crawford flour. The intensity of the resolved bands of untreated soybean flour (raw) was higher than that of the treated ones. In addition to, the fractions of all soybean protein concentrates samples were extremely decreased, while the basic protein patterns were nearly disappeared.- Saponin content: The results of saponin content indicated that soy protein concentrates of the two varieties were higher than that of corresponding soybean flour.
|
|
|