The addition of hydrolyzed whey protein fractions to raw pork patties with subsequent chilled storage and its effect on oxidation and gel properties

Abstract

This experiment was conducted to elucidate the protein oxidation and gel properties of whey protein hydrolysates that were mixed into raw pork patties with subsequent chilled storage. Whey protein polypeptides of different size classes (Fraction I, MW > 10 k; Fraction II, MW 3–10 k; Fraction III, MW < 3 k) were separated by ultrafiltration and the pork patties were stored for 0, 2, 4, 6, and 8 days at 4°C. The contents of thiobarbituric acid-reactive substances (TBARS), carbonyl groups, and gel textural properties were determined. The results showed that there was no significant difference at the beginning of the storage period between the treatment groups that contained whey polypeptides or BHA and the control group (P > 0.05). After 2 days of storage, Fraction III (F3) was superior to Fraction I (F1), Fraction II (F2), and the control in inhibiting the oxidation of pork patties and improving gel quality. In addition, F3 also had a higher water-holding capacity and storage modulus, which was similar to the 0.02% butylated hydroxyanisole (BHA) group. The amino acid compositions showed that F3 had relatively higher contents of histidine, arginine, and proline, demonstrating a strong potential for F3 to be used as a natural antioxidant in raw pork preservation.