Chemical and enzymatic modification of whey proteins
type: CreativeWork
description: "Chemical and enzymatic modifications of whey proteins and their effects on the protein's structural and functional properties were studied. Chemical modification by acylation improved the surface properties of the proteins. Succinylation, in particular, imparted a significant resistance against browning development upon storage in an intermediate moisture system. Enzymatic deamidation, via trypsin and chymotrypsin, resulted in proteins with improved solubility and enhanced in vitro digestibility. Enzymatic hydrolysis of whey proteins was performed using six different enzymes, namely, trypsin, chymotrypsin, papain, bromelin, pepsin and pronase. Efficiency of the hydrolytic process was evaluated by monitoring parameters such as temperature, pH, substrate concentration, enzyme to substrate ratio and ionic composition. Correlation of the enzymes' mode of action on whey proteins to their hydrolytic power was studied in comparison to other proteins with different molecular structures. Separation and recovery of the hydrolyzed fractions was achieved using two hollow fiber membranes of different molecular weight cut-offs arranged in series. Physicochemical characterization of the recovered whey protein fractions showed that this treatment affected the secondary structure of the proteins to various degrees as evidenced by their circular dichroic profiles. Interactions of the modified proteins with other proteins, lipids and mineral ions were compared to those of the native whey protein. Interaction of the modified proteins with gluten took place by two different mechanisms, namely, hydrophobic interaction and disulfide-sulfhydryl groups interchange. The improved performance of the modified proteins with gluten enhanced foaming power as shown in the reduction of foam drainage volume and prolonged life-time of the foams. Gels from modified whey proteins with gluten exhibited smoother texture, improved strength and unique ultrastructural properties as evidenced by scanning ele…
abstract: "Chemical and enzymatic modifications of whey proteins and their effects on the protein's structural and functional properties were studied. Chemical modification by acylation improved the surface properties of the proteins. Succinylation, in particular, imparted a significant resistance against browning development upon storage in an intermediate moisture system. Enzymatic deamidation, via trypsin and chymotrypsin, resulted in proteins with improved solubility and enhanced in vitro digestibility. Enzymatic hydrolysis of whey proteins was performed using six different enzymes, namely, trypsin, chymotrypsin, papain, bromelin, pepsin and pronase. Efficiency of the hydrolytic process was evaluated by monitoring parameters such as temperature, pH, substrate concentration, enzyme to substrate ratio and ionic composition. Correlation of the enzymes' mode of action on whey proteins to their hydrolytic power was studied in comparison to other proteins with different molecular structures. Separation and recovery of the hydrolyzed fractions was achieved using two hollow fiber membranes of different molecular weight cut-offs arranged in series. Physicochemical characterization of the recovered whey protein fractions showed that this treatment affected the secondary structure of the proteins to various degrees as evidenced by their circular dichroic profiles. Interactions of the modified proteins with other proteins, lipids and mineral ions were compared to those of the native whey protein. Interaction of the modified proteins with gluten took place by two different mechanisms, namely, hydrophobic interaction and disulfide-sulfhydryl groups interchange. The improved performance of the modified proteins with gluten enhanced foaming power as shown in the reduction of foam drainage volume and prolonged life-time of the foams. Gels from modified whey proteins with gluten exhibited smoother texture, improved strength and unique ultrastructural properties as evidenced by scanning ele…
author: Lakkis, Jamileh M.
language: eng
keywords: Agriculture, Food Science and Technology
date published: 2011-05-07T12:41:52Z
date modified: 2026-07-22T22:25:16Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/20530