Tomato and pepper waste in sustainable laying hens diet for improving nutritional and organoleptic characteristicosf eggs

Fresh tomatoes (T) and peppers (P), waste unsold from local markets, were supplemented to laying hens diet, with the aim to evaluate their nutraceutical effect on hens performance and eggs quality. Forty ISA Brown laying hens (70-weeks-o1d) reared in outdoor system, were divided into 2 groups of 20 hens each and fed a basal diet (C group) or a basal diet supplemented with 300 g/kg of T + 230 g/kg of P (TP group). After 3 months, hens body weight (BW) was recorded and 15 eggs sampled from each group. Eggs weight (EW) was registered and egg mass (EM) calculated. Chemical composition and cholesterol content were determined. The color and odor profile of yolk was evaluated using an E-Eye and an E-Nose. Performance and chemical data were submitted to ANOVA and sensorial data to a DFA analysis. Results showed the positive effect of use of T and P on palatability of the diet and confirmed the nutraceutical effects of T and P, increasing BW (2,0718 TP vs 1.913g C), EW (51 g/hen/day TP vs 47 g/hen/ day C), and reducing cholesterol content (1,71 mg/100g TP vs 2.08 C mg/100g). The addition of T and P in the diet strongly influenced the organoleptic profile of egg’s yolk. For the color profile, the E-Eye showed a clear separation of the C group from the TP group. C group was characterized by RGB color codes corresponding to shades of yellow (2416, 2400, 2144, 2128, 1872), in contrast to the TP group, which was characterized by color codes corresponding to shades of orange (1328, 1584, 1600, 1824, 1840, 1856). Even for the odor profile, E-nose showed a clear separation between the groups. The P- and T-type sensors, corresponding to hydrocarbons, head toward the TP group, probably due to the high carotenoids content of T and P. The results obtained demonstrate that principles of circular economy, can be considered useful for the production of sustainable eggs with improved nutritional and organoleptic characteristics.