Theses and Dissertations


Yin Zhang

Issuing Body

Mississippi State University


Haque, Zahur Z.

Committee Member

Silva, Juan L.

Committee Member

Williams, J. Byron

Date of Degree


Document Type

Graduate Thesis - Open Access

Degree Name

Master of Science


Hydrolysis of casein using chymotrypsin results in the formation of polypeptides (CH) with a hydrophobic aromatic amino acid on one end of the chain because the enzyme selectively cleaves the adjacent peptide-bond. Due to resonance of the aromatic micro-domain, thiols become redox-sensitive and actively participate in electron transfer. These types of amphipathic peptides also tend to be membrane-lytic. The two prong approach of this investigation was to, (1) assess antibacterial effect of the CH in beef steak, and (2), to determine its antioxidative efficacy as a constituent of Cheddar whey based edible coating mix. The edible coating prevented coliform growth even at a minute concentration range of 0.15-0.2 % (w/v). Marked antioxidative efficacy of the CH, particularly at a concentration of 0.3% (w/v), was also evident from its remarkable free radical scavenging ability and extended resilience in an abusive model system saturated with peroxyl-radicals generated through controlled pyrolysis.