EFFECT OF ADDITION OF DIFFERENT TYPES OF SOYBEAN ON PROTEIN QUALITY OF PROCESSED KOFTA AND BURGER.

The present work was carried out to study the effect of addition soybean products, namely Soy Protein Isolate (SPI) by substitution from meat at three levels (2, 3 and 4%), Textured Soy Protein (TSP) and Defatted Soy Flour (DSF)  by substitution from meat at three levels (2.5, 3.75 and 5%) on protein quality of some meat products (kofta and burger). Processed meat products were evaluated chemically during frozen storage at -18˚C for 6 months. Results indicated that all processed kofta and burger formulas prepared with 2 and 3% SPI have the high amount of protein content being 20.05, 20.59 and 20.21, 20.71% respectively. Results of chemical analysis showed that total volatile nitrogen (TVN) of processed kofta and burger with different soy bean products was decreased in compare with control samples at zero time and during frozen storage periods. Also, TVN values were ascendingly increased as a result of freezing storage. TVN values of kofta were ranged from 11.96 mg/100g at zero time to 23.32 mg/100g for samples 6 months of frozen storage, while TVN values of burger were ranged from 11.61 to 21.75 mg/100g after 6 months of frozen storage respectively. Highest values of TSN were registered for kofta and burger samples substituted with 2 and 3% SPI which ranged from 0.86 to 0.38 and from 0.89 to 0.41 mg/100 gm sample, 0.80 to 0.35 and from 0.84 to 0.38 mg/100 gm sample at zero time and 6 months of frozen storage respectively in compare with control samples were 0.74 to 0.28 and from 0.69 to 0.24 mg/100 gm sample, Result of amino acids analysis indicated that the total amount amino acids in kofta samples ranged from 99.75 to 99.98(g/100g protein). Total essential amino acid (T.E.A.A. ( were decreased in all processed kofta samples from 46.6 to 45.38 in compare with control sample, while the total amino acids in burger formulas ranged from 99.81 to 99.99 (g/100g protein). Total essential amino acid (T.E.A.A. (were decreased in all processed burger samples from 46.92 to 45.61 in compare with control sample, the predominate essential amino acids in both of kofta and burger formulas was lysine. Results indicated that restrict amino acid (RA) was tryptophan in kofta and burger formulas. Results of biological value (BV) indicated that samples of kofta processed with 2% SPI had (77.97). While samples of burger processed with 2% SPI had (78.18). So, it could be recommended that substitution of meat by soy products SPI (2, 3%) and (2.5, 3.75%) of TSP and DSF could enhanced the protein quality of processed meat products.