Study On Extraction Of Mung Bean Albumin And Their Functional And Physico-chemical Property

Mung bean is a high quality plant protein resource crop, which accounts for about30%of theprotein content of nutrients.Mung bean protein is composed mainly of albumin, globulin.Thealbumin is available water extraction of proteins with best amino acid ratio.Extraction of mungbean albumin is to improve comprehensive utilization of mung bean value.This paper focuses onthe study of extraction of mung bean albumin, and analyzes the function characteristics and basiccharacterization.(1) The optimal extraction conditions of mung bean albumn was: extraction time3.5h,acidpH4.6, extraction temperature31℃, ratio of solid to liquid1:20g/mL;the protein extraction ratewas22.68%and potein purity extracted under the optimal conditions was88.96%. Significantanalysis result showed that:extraction time,extraction temperature are the very significant factors(p<0.01), the ratio of material to liquid as significant factor (p<0.05), acid precipitation of pHhad no significant effect on the extraction rate (p<0.05).(2) Test of the functional properties of albumin showed that:at room temperature, near theisoelectric point(pH4.6)，the solubility mung bean albumin (7.66%) and water holding capacity(2.78g/g)；in pH(7),the solubility (57.09%) and water holding capacity (5.02g/g);under neutral,conditions at40℃the solubility (79.32%)and water holding capacity(5.36g/g).With elevatingtemperature, mung bean oil absorption of albumin was decreasing; increasing concentration ofmung bean albumin, its emulsifying and emulsion stability, foaming and foaming stability wereincreasing, but the increase was slowing.(3)SDS-PAGE test showed that, mung bean albumin containing protein molecular weight were136.88,61.56,48.99,29.88,25.66,20.42ku;the bands of48.99ku was darker, showed the mungbean albumin molecular weight distribution mainly concentrated in the48.99ku. Thermaldenaturation test results showed, initial denaturation temperature was100.3℃,Td mung beanalbumin denaturation temperature (116.5℃),ΔH (3.382J/g), meant the mung bean albumin withgood thermal stabilit.Through the study of the optimum technological parameters of water extraction and acidprecipitation process of mung bean albumin, protein extraction rate reached86.71%, mung beanalbumin powder purity is88.96%. Mung bean albumin has better solubility, water holding capacity, emulsification, foaming properties and thermal stability.Mung bean albumin extractioncan be carried out before the mung bean starch production, improve the effective utilization rateof mung bean.