Mechanically Activated Enzymatic Hydrolysis of Pea Seeds and Its Effects on Bakery Products

Plant-derived protein hydrolysates are efficient sources of easily digested water-soluble nutrients. Pea is a promising crop, which is rich in protein. In this study, combining mechanical pretreatment of pea seeds and their enzymatic hydrolysis into a single manufacturing stage has been suggested to increase yields of water-soluble substances. Resulting hydrolysates were used as ingredients for bakery products. Material and Methods: In this study, mechanical pretreatment of pea seeds included two stages. At the first stage, feedstock was subjected to preliminary comminution to particles of < 2 mm using knife grinder. At the second stage, feedstock underwent mechanical treatments in presence of enzyme products using RM-20 centrifugal roller mill. Enzymatic hydrolysis of the mechanically treated pea seeds was carried out at 50 °C and 120 g. Dough for the bakery products was prepared using two methods of sponge-and-dough and straight-dough. Total proteins in the hydrolysates and end products were assessed using Bradford protein assay. Quantities of free amino acids were assessed using liquid chromatography-mass spectrometry and Agilent 1200 Liquid Chromatography System. Results and Conclusion: In this study, the optimal hydrolysis time was reported as 4 h and the enzyme product concentration of 2%. The optimal time of mechanical pretreatment of the raw materials in centrifugal roller mill included 40 s at 1500 g. Resulting pea seed hydrolysates were added to bakery products. Sponge-and-dough method was reported as the optimal method of preparing doughs with the hydrolysates since the end products included the best sensory characteristics. Due to the cleavage of peptide bonds by the enzyme products, addition of the hydrolysates ensured higher contents of amino acids and short peptides in the end products.