Turmeric (Curcuma longa L.) extract on oxidative stability, physicochemical and sensory properties of fresh lamb sausage with fat replacement by tiger nut (Cyperus esculentus L.) oil.

This study aimed to evaluate the effect of turmeric extract as natural antioxidant on modified atmosphere-packaged fresh lamb sausages with fat replacement during storage (2 °C). Five treatments were prepared: control without antioxidant (CONT); with 500 mg/kg sodium erythorbate (E500); and three batches with 250, 500 or 750 mg/kg turmeric extract (T250, T500 and T750), respectively. The proximate composition, pH, color, texture, oxidative stability, sensorial analysis, free fatty acids and volatile compounds of sausages were analyzed. Turmeric extract improved the antioxidant capacity of lamb sausages and also slowed lipid oxidation and the generation of related volatile compounds. Moreover, physic-chemical parameters of lamb sausages were not greatly influenced by turmeric addition and concentration, except for yellow color. All samples were considered acceptable by consumers. These findings showed that turmeric extract is effective against lipid oxidation and could be a good strategy to enhance the shelf life of lamb sausage.

Effect of guarana (Paullinia cupana) seed and pitanga (Eugenia uniflora L.) leaf extracts on lamb burgers with fat replacement by chia oil emulsion during shelf life storage at 2 °C.

The effects of guarana seed and pitanga leaf extracts on the physical-chemical and sensory characteristics, and oxidative stability of modified atmosphere-packaged lamb patties with fat replacement during storage (2 °C) were investigated. Four treatments were prepared: control (without antioxidant); with BHT (10 mg/kg); with 250 mg/kg guarana extract (G250); with 250 mg/kg pitanga extract (P250). Analysis included the proximate composition (moisture, protein, fat, and ash) and sensory acceptance (day 0); pH, color (L*, a*, b*), TBARs, carbonyl content, DPPH, and visual sensory assessment (0, 6, 12, and 18 days); fatty acid profile and volatile compounds (0 and 18 days). G250 and P250 did not alter the centesimal composition and the acceptance of the lamb burgers on day 0. The extracts also delayed discoloration of the burgers, endowed the reddest intensity, and retarded lipid and protein oxidation throughout storage time, particularly P250, which presented the lowest TBARs levels (6.92 mg MDA/kg) and carbonyl values (5.59 nmol carbonyl/mg), and the highest antioxidant activity (249.48 µg Trolox/g), at day 18. The MUFA, SFA, and PUFA levels, AI, TI, and h/H ratio were comparable between treatments; only the n-6/n-3 ratio was higher in P250 treatment but within the recommended levels. More volatile compounds were derived from lipid oxidation in the control and BHT treatments than G250 and P250 treatments. As a result, both G250 and P250 groups are effective against color deterioration, and lipid and protein oxidation, without impairing the sensorial characteristics, representing a promising alternative to replace synthetic antioxidants by natural products in lamb burger.

Natural antioxidants in processing and storage stability of sheep and goat meat products.

Oxidative damage is one of the main reasons for loss of quality in sheep and goat meat and meat products. Synthetic antioxidants are the current solution to stabilize oxidative process and extend the shelf life of such products; however, the negative impact on health may impose a risk to consumers. Natural antioxidants, extracted from several vegetable sources, have been considered an attractive alternative for this conflicting situation. Phenolic compounds are minor components in herbs, spices, tea and fruits that display potential application against the progression of lipid and protein oxidation and their consequences for meat quality, which can even overcome the protective effect of synthetic compounds. This review aims to discuss the mechanisms associated to lipid and protein oxidation and their implications on meat quality attributes and provides recent data regarding the application of natural antioxidants in sheep and goat meat products, which have a high susceptibility to oxidative processes compared to other red meats.