The invention relates to a composition which comprises component (1) and at least one of components (2), (3) and (4): (1) a completely water-soluble antioxidant which is a Labiatae tissue extract containing sodium rosmarinate; (2) ascorbic acid, isoascorbic acid and (or) their non-toxic water-soluble salts in a weight ratio to sodium rosmarinate of 1.5:1 to 90:1; (3) citric acid, its non-toxic salts, and (or) non-toxic water soluble salts of acetic and (or) lactic acids; (4) at least one non-toxic salt of propionic acid. Embodiments of such compositions are useful for enhancing the antioxidative protection afforded to meat products, or to edible oils or fats (or foodstuffs containing them), and for enhancing inhibition of microbial deterioration in foodstuffs provided by the acids and salts specified in ingredients (3) and (4).