Evaluation of clear flour–a by-product of semolina manufacturing—for production of protein isolate to be used as egg-replacer in muffin cakes
摘要
Two different defatted clear flours (dCF-1 and dCF-2) were used for production of protein isolates (PI). Protein contents of dCF-1 and dCF-2 were 14.2% and 17.7% on dwb, respectively. PI were produced from dCF-1 and dCF-2 by using distilled water (PI-1W and PI-2W) or 0.15 M NaCl (PI-1S and PI-2S), respectively. PI was investigated on SDS-PAGE for monitoring the molecular weight distributions of proteins. Techno-functional properties, such as solubility, foaming, water holding and oil absorption capacities of PI were investigated. Some PI was used as egg replacer in muffin cake (MC) formulations. Protein contents of PI-1W, PI-2W, PI-1S and PI-2S were 93.4%, 88.7%, 90.8% and 91.0% on dwb, respectively. Water holding capacities of PI-1W and PI-2W were higher than that of PI-1S and PI-2S. The highest protein solubility (81.9%) was determined with PI-1W at pH 2. The highest foam volume (115.8 cm3) and foam half-life (116.3 s) were determined with PI-2W at pH 8 and PI-1W at pH 2, respectively. The MC prepared with 3.0% (w/w) PI-2W or PI-1W was similar to control in terms of physical and textural properties, respectively.