Exploring the synergistic effects of essential oil and plant extract combinations to extend the shelf life and the sensory acceptance of meat products: multi-antioxidant systems.

To develop multi-antioxidant systems for the preservation of meat products, mixtures of essential oils or plant extracts were investigated for their antioxidant interactions. The combinatorial study revealed that the chemical diversity of both major and minor components of these ingredients contributed to the antioxidant interactions. A shift from antagonistic or additive interaction to synergistic one was achieved by modulating the ratio of mono-components of multi-antioxidant systems. Mixtures containing oregano/thyme (25/50 of IC50), thyme/clove (25/100) and thyme/cinnamon (50/25) oils as well as cranberry/rosemary (25/25), cranberry/green tea (25/25), cranberry/apple (25/25), rosemary/apple (50/25) and grapeseed/cranberry (50/50) extracts have shown synergistic antioxidant effects. Among the investigated systems, thyme/clove oils and oregano/thyme oils/grape-seed extract systems have extended, in situ, the shelf-life of chicken and ground pork products stored at 4 °C by 2 to 4 folds. The sensory acceptability of treated samples was rated to be moderately better than control. This study lays the ground for the development of efficient natural multi-antioxidant systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05653-4.

Barley protein concentrates: Extraction, structural and functional properties.

Protein concentrates were prepared from defatted barley (Hordeum vulgare L.) flour using alkaline and enzymatic treatments. Milder enzymatic treatments included (i) a bi-enzymatic method involving the use of starch-hydrolyzing enzymes, and (ii) a tri-enzymatic method using the former bi-enzymatic treatment followed by digestion with glucanase. The concentrate obtained through alkaline extraction (AI-BP) was comprised mainly of low molecular weight fractions of proteins. Bi-enzymatic treatment produced a protein concentrate with the highest protein content (49.0%), while those obtained by the tri-enzymatic treatment followed by an isoelectric precipitation step (TEI-BP) gave the highest protein recovery yield (78.3%). In both of the latter concentrates, 35 kDa B-hordeins were the major protein fraction. Divergence in secondary/tertiary structure elements (AI-BP; TEI-BP) was obtained and attributed to the difference in the protein profiles. Further characterization of protein concentrates indicated that they exhibit pseudoplastic behavior. Emulsifying capacity of concentrates was comparable to that of whey protein isolate.