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Hi, I am looking for someone to write an article on q1./ discuss how the primary, secondary and tertiary structure of a protein will influence the way in which it behaves when it a Paper must be at le

Hi, I am looking for someone to write an article on q1./ discuss how the primary, secondary and tertiary structure of a protein will influence the way in which it behaves when it a Paper must be at least 1000 words. Please, no plagiarized work! The stability of the system is controlled by the strength of the absorbed protein film around the dispersed droplets and the balance of repulsive and attractive forces of interactions among neighboring droplets and previous favoring droplet flocculation (Papadopoulos, 2008). The absorbed protein molecules on the surface of oil droplets, to some extent, influence the interactions among droplets and, thus, determine the physical stability and rheological properties. After adsorption on the interface, molecules exhibit a conformation that is influenced by molecular flexibility and environmental factors, including ionic strength, presence of low molecular weight emulsifiers or other proteins, and pH. These factors affect the strength of droplet-droplet interactions, protein hydrophobicity, or molecular charge. Protein can undergo irreversible changes during heat treatment. At 65 ?C, whey proteins unfold, exposing previously hidden hydrophobic groups into the surface of the molecule (Raikos, 2010). Such structural change can affect the functionality of the protein. When this change at molecular level is irreversible, the protein molecule has undergone denaturation. Heating whey proteins, at increasing heating temperature, results in the formation of small aggregates of ?-lactoglobulin. These small aggregates form bigger aggregates when ?-lactoglobulin denatures at increasing heating time. When heating time or temperature is raised, ?-lactalbumin denatures and forms complexes with the denatured ?-lactoglobulin. Both ?-lactalbumin and ?-lactoglobulin bind on the surface of casein micelles. During emulsification, milk proteins can rapidly adsorb on the surface of newly formed oil droplets. This adsorption decreases interfacial tension and leads to the formation of thick layers that prevent the flocculation or coalescence of oil droplets through electrostatic and steric stabilization mechanisms. Different proteins in a food system exhibit different degree of stabilizing and emulsifying properties due to their variation in their molecular structure, functionality, flexibility, hydrophobicity, charge, and molecular size. As well, the thermal stability of a protein-stabilized emulsion likely depends on the properties of proteins used in the preparing the emulsion. For instance, both caseinates and whey proteins are milk protein, but caseinates have globular structures that are sensitive to heat (Dalgleish, 2006). Hence, emulsions that contain whey protein may exhibit extensive destabilization due to heat treatment at temperatures above the protein’s denaturation point. The flexible and more disordered molecular structure, as compared with that of whey protein, of caseinates is not heavily altered by heat treatment. Thus, casein stabilized emulsions are less susceptible to heat aggregation. Caseins and whey proteins are commonly used as ingredients in food emulsions because they are excellent emulsifier and emulsion stabilizers. Whey protein concentrates and isolates are chiefly composed of ?-lactalbumin (?-la), bovine serum albumin, ?-lactoglobulin (?-lg), which are sensitive to heat and denature at relatively moderate temperatures. The denaturation of their structures, to a lesser extent, may also cause by their adsorption to the emulsion droplet surface.

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