Characterization of goat milk protein and comparison of milk proteins using polyacrylamide gel electrophoresis

Goat milk has been a rich source of proteins. The distinctive composition of goat milk, combined with its nutritional value, is linked to the liberation of protein fragments during digestion or technological processing, which are able to perform various biological activities. This has gain more attention due to its broad applications in the food, drug, and various other industries. Thus, here we characterized goat milk proteins to evaluate the protein function. This study is entitled to exemplify the proteome of goat milk of three Indian goat breeds Jamnapari (160), Barbari (110), Jakhrana (20) and to find the variants using SDSPAGE. The electrophoretic pattern of goat milk samples showed the presence of four major casein variants, i.e., CSN1S1, CSN1S2, CSN2, CSN3 and two whey proteins, viz., β-lactoglobulin and α-lactalbumin. These major proteins exhibits variants i.e. CSN1S1*A 0.92 (Jamnapari), 0.83 (Barbari) 90 and 0.8 (Jakhrana), CSN1S1*B 0.1 in all the three breeds. CSN1S2*A 0.03 in barbari though was not found in jamnapari and jakhrana breeds. and CSN1S2*B 0.95 (Jamnapari), 0.78 (Barbari), 0.8 (Jakhrana). No polymorphism was observed at CSN2, CSN3 and α-lactalbumin locus in our study. However, frequency of β-LGA and β-LGB was 1 and 0,12 (Jamnapari), 1 and 0.1 (Barbari) and monomorphic in Jakhrana, respectively these studies also implied that variant A was present in all the breeds where as B 0.12 (jamnapari) and 0.1 (barbari) and in jakhrana B was not found. The major proteins in milks from bovine, caprine, and from humans were compared using a SDS PAGE method. Electrophoretic analysis of goat milk proteins showed the presence of variants. Cow milk and goat milk has shown approximately same protein composition where as human milk when compared to cow and goat milk has shown the absence of Alpha S1 casein protein which has a major role in milk protein allergies and βlactoglobulin which is a major whey protein.