Abstract
Protein hydrolysates (PH) with a degree of hydrolysis (DH) of 5%, 10%, and 13% from two varieties of peanut were prepared using two commercial enzymes, Alcalase and Flavourzyme. The content of essential amino acids (30,290 mg/100 g) and hydrophobic amino acids (34,067 mg/100 g) of the peanut variety Kalasin 2 (KAC431) protein was higher than that of a common variety, Kalasin 1 (KAC1) (p < 0.05). The protein molecular weight distributions of the two varieties of peanut detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were similar, ranging from 15 to 75 kDa, with a major protein band at 50–75 kDa. The antioxidant and functional properties of derived PHs were influenced by DH. Although the foaming ability of protein was improved by DH5%, it was obviously decreased upon increasing DH further. The best emulsifying properties were observed in PH with DH5% (p < 0.05). The incorporation of PH with a small DH, especially when produced using Flavourzyme, had a highly positive impact on the specific volume and relative elasticity of gluten-free bread. The effect of PHs on bread quality was highly correlated with their functional properties. This study suggests that partially enzymatically modified proteins are suitable for incorporation in food products such as bread and other gluten-free products.
Highlights
Wheat flour is used as the main ingredient in most bread because it contains the storage protein gluten, a critical factor for dough structure
Where B is the volume of NaOH used, Nb is the normality of the NaOH, Mp is the mass of protein in grams (N × 4.60), htot is the total number of peptide bonds in the protein substrate, and α is the average degree of dissociation of the α-NH2 groups, which can be calculated from the following equation: α = (10pH-pKa /1 + 10pH-pKa )
KAC431 and KAC1 with DH5% and DH10% were comparatively obtained at 3 and 45 min, respectively, with Protein hydrolysates (PH) yields ranging from 65.71% to 68.95%
Summary
Wheat flour is used as the main ingredient in most bread because it contains the storage protein gluten, a critical factor for dough structure. The development of gluten-free bread has gained much attention from researchers and/or food recipe developers worldwide due to its highest popularity among gluten-free baked products. Many hydrocolloids, such as egg white solids [2], inulin [3], and gums [4], have been studied for substituting or imitating the gluten network in gluten-free breads. Rice bran protein concentrate is optimal for improving the quality of gluten-free bread, whereas the addition of more than 2% protein has a negative effect on gluten-free bread quality This is due to the restricted functional properties of the native protein, leading to poor bread quality. Protein hydrolysates prepared using two commercial enzymes with different degrees of hydrolysis were assessed for their chemical and functional properties, and further applied in gluten-free rice bread. The impact of selected protein hydrolysates on the bread quality parameters, such as weight loss, specific volume, crumb firmness, and relative elasticity, of the final products was investigated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
