Optimized Extraction and Characterization of Sesame Seed Press Cake Protein and its Application in the Formulation of Meatball Analog

In this study, extraction of protein from sesame seed press cake (SSPC) was optimized. SSPC protein isolate was subjected to enzymatic hydrolysis and both SSPC protein isolate and hydrolysates were characterized by SDS-PAGE, gel filtration chromatography, Fourier transformed infrared spectroscopy (FTIR) and circular dichroism (CD) spectroscopy. Meatball analogs containing SSPC protein isolate (15 and 20%) were prepared and evaluated for sensory attributes. The extraction at optimized conditions resulted in protein yield of 20.87 ± 0.57% with protein content of 92.1 ± 1.82%. Water holding capacity (WHC) and oil holding capacity (OHC) of SSPC protein isolate were 1.47 ± 0.04 g/g and 5.86 ± 0.10 g/g, respectively. Densitometric analysis showed that 7S globulins (55–60 kDa) were the major protein bands in SSPC protein isolate and this finding was further supported by gel filtration chromatography. CD spectroscopy revealed that SSPC protein isolate contained 23.4% α-helical structure which after hydrolysis was reduced to 12.6%. FTIR analysis revealed the presence of Amide, I, II and III in protein isolate and hydrolysates. The incorporation of SSPC protein isolate resulted in a decrease in fat content whereas, the protein content of meatball analog was increased up to 42.43% in comparison to control formulation (22.68%). The meatball analogs received acceptable sensory scores and the addition of SSPC protein had no overall negative impact on the sensory scores. SSPC protein due to its low cost and functional attributes can be used in the formulation of meatball analogs.