Effect of different concentrations of gellan gum with/without 0.50% basil essential oil on the physicochemical properties of gellan gum-rice bran oil coating emulsions and their application in egg preservation.

This work investigated the effects of different concentrations (0.10 %, 0.15 % or 0.20 %, w/v) of gellan gum (GG) with/without 0.50 % (v/v) basil essential oil (BEO) on physicochemical properties of gellan gum-rice bran oil (GG-RBO) emulsions. The results showed that GG-RBO emulsions with 0.15 % or 0.20 % GG were more stable than GG-RBO emulsion with 0.10 % GG (as evidenced by higher apparent viscosity and absolute zeta potential, but smaller average particle size and lower turbidity), thus displaying better coating performances (as evidenced by bigger contact angle but lower moisture content). The presence of BEO further improved their stability and coating performances. Coating with GG-BRO or GG-RBO-BEO emulsion with 0.15 % GG significantly delayed the increase in weight loss, and the decrease in haugh unit, yolk index and albumen pH of eggs during 42 days storage; moreover, GG-RBO-BEO emulsion caused lower total aerobic plate count. Therefore, GG-RBO, especially GG-RBO-BEO emulsion has potential in egg preservation.

Individual effects of rosemary extract and green tea polyphenols on the physicochemical properties of soybean oil-myosin emulsion with l-arginine or l-lysine.

This study aimed to investigate the individual effects of rosemary extract and green tea polyphenols on the stability of the soybean oil-myosin emulsions with l-arginine or l-lysine. The results showed that l-arginine or l-lysine increased the physical stability of emulsion in all cases. In the presence of metallic cations, rosemary extract increased the physical stability, while green tea polyphenols decreased the physical stability. l-Arginine or l-lysine retarded the lipid and protein oxidation of emulsion in the absence of metallic cations during storage, but accelerated it in the presence of metallic cations. The two antioxidants delayed l-arginine- or l-lysine-induced lipid and protein oxidation in the presence of metallic cations. The results provide a new method for improving the physical and chemical stability of emulsion sausages in which l-arginine or l-lysine is applied to improve the quality attributes of emulsion sausage.