Alternative plant protein powder production for food industry

In this thesis, it is aimed to produce plant based protein powder in maximum yield from sugar beet leaves. In order to obtain maximum protein yield, isoelectric precipitation, ammonium sulphate precipitation and isoelectric-ammonium sulfate precipitation methods have been applied. In addition, in order to increase protein yield, the effective parameters in the extraction process were optimized and enzymatic pretreatment was applied. In this context, it was determined that sugar beet leaves contained 24,02±0,18% protein on dry matter basis. It was determined that the highest yield of protein powder was obtained by applying isoelectric-ammonium sulfate precipitation. The extraction temperature (25-75 ˚C), the extraction time (40-120 min) and the solvent:solid ratio (15-45 mL/g), which are the effective parameters in the extraction process, were optimized by the response surface methodology and according to the results of the optimization, protein yield was found 55,15±2,82% at the extraction conditions of 54,25 ˚C temperature, 81,35 minutes extraction time and 27,65 mL/g solvent:solid ratio. Alsothe optimization process results were 54,25 ˚C temperature, 81,35 minutes extraction time and 27,65 mL/g solvent:solid ratio. Also, with enzyme-assisted extraction protein yield increased by 43,27% was determined as 79,01±0,27%. The protein content of the protein powders was 69,08±0,59% (w/w) on a dry matter basis. When the amino acid composition of protein powders is examined, it was detected that the essential amino acids of threonine (4,20%), valine (3,99%) and phenylalanine (3,62%) and non-essential amino acids of serine (55,22%) and aspartic acid (7,41%) were found to have a significant amount. The protein solubility of the protein powders was found to be 98.71% at pH 7.5. In addition,color, bulk density, tapped bulk density, Carr Index, particle density, wettability, dispersibility and water activity were determined to determine the quality characteristics of protein powders.