Lemon co-products as functional ingredients for mortadella reformulation: Impact on shelf life, nutritional quality...

High consumption of processed meats is associated with higher intakes of refined sugars, sodium, and fats, and lower intakes of phytochemicals and dietary fibres, prompting a search for healthier processed foods. Lemon by-products, which account for up to 50 % of lemon production, are rich in bioactive compounds and represent a promising functional ingredient. This study examined the effects of incorporating lemon dietary fibre (LDF) and/or lemon phenolic compound-rich extract (LPC) recovered from lemon by-products into mortadella. Four formulations were developed: Control (CS), LDF (3 %), LPC (1 %), and LDF (3 %) + LPC (1 %). The nutritional, technological, microbiological, phenolic content, and sensory properties of the reformulated mortadellas were assessed through shelf-life analysis during 28 days, with sampling at days 0, 7, 14, 21, and 28. Inclusion of LDF significantly (p < 0.05) affected moisture, protein, and colour parameters over time. At day 0, the incorporation of LDF increased protein content (16.47 % vs 15.52 % in CS), reduced moisture (62.67 % vs 65.46 % in CS), and enhanced lightness (L* = 67.49 vs 63.62 in CS). Notably, LDF caused a significant reduction in residual nitrite levels (p < 0.05), decreasing from 70.50 mg/kg in the control to 36.93 mg/kg at day 0, and from 35.66 mg/kg in the control to 7.85 mg/kg at day 28, indicating its potential to enhance product safety. HPLC analysis confirmed the presence of eriocitrin and hesperidin in the mortadellas. Formulations containing LPC, which contains vitamin C, highlight their potential as natural antioxidants to reduce lipid oxidation. Moreover, formulations containing LPC, despite the absence of sodium ascorbate, demonstrated excellent microbiological stability (< 2.5 log cfu/g) over 28 days of storage. Sensory evaluation revealed strong acceptance by panellists, confirming their suitability for use in meat products. Overall, incorporating lemon co-products into mortadella provides a practical way to enhance shelf life, nutritional profile, and safety of processed meats.