Utilization of Tomato ( <i>Solanum lycopersicum</i> ) Peel Powder as a Flavor Enhancer and Natural Antioxidant in Sausage Formulation

This research was aimed at investigating the potential of utilizing antioxidant-rich tomato peels, an underutilized byproduct in agroindustry, for enhancing the quality and nutritional attributes of sausages. The study incorporated varying concentrations and particle sizes (0.425 mm coarse/RD vs. 0.18 mm fine/RE) of tomato peel powder into sausage formulations, followed by an assessment of their sensory characteristics and antioxidant capacity. Results indicated that the inclusion of tomato peel powder led to a decrease in brightness (<i>L</i> ^∗) while augmenting redness (<i>a</i> ^∗) and yellowness (<i>b</i> ^∗) parameters compared to the control group. Moreover, it positively influenced the flavor profile of the sausages, with overall acceptability scores surpassing 7 across all test groups containing tomato peel powder (though the control group scored 4.13 in aroma). The study also revealed that tomato peels had a retarding or inhibitory effect on lipid oxidation within the sausages, with coarse particles (0.425 mm) showing significantly stronger suppression than fine particles (0.18 mm). Throughout a 24-day refrigerated storage period, TBARSs (thiobarbituric acid reactive substances) and POV (peroxide value) measurements were notably slower in the treatment groups, particularly RD20 (20% starch substitution with 1.0% tomato peel powder) and RD40 (40% starch substitution with 2.0% tomato peel powder), as opposed to the untreated samples. Notably, RD10 (10% starch substitution with 0.5% tomato peel powder) exhibited the longest oxidation induction period (8.2 h vs. RD20's 7.3 h). DPPH radical scavenging activity assays showed that sausage formulations with 20% starch substitution (1.0% tomato peel powder) exhibited stronger antioxidant capacity than those with 0.01% butylated hydroxytoluene (BHT). Finally, the use of coarse particles of tomato peel enhanced the fatty acid profile by improving PUFA retention; for instance, the RD10 treatment showed a 12.3% increase compared to RE10, thereby improving the sausages' nutritional quality. This study underscores the feasibility and benefits of valorizing tomato peels with optimized particle size and substitution ratio in sausage production for improved product quality and sustainability.