Coffee silverskin extract-functionalised pectin: a sustainable substrate to obtain chicken meatballs with antioxidant and improved sensory properties

Abstract

High-methoxyl pectin, functionalised with phenolic compounds extracted from coffee silverskin, was used in chicken meatballs formulation for improving antioxidant and sensory properties of the final product. An enzymatic conjugation process was applied to obtain the functional pectin then added at the level of 2.5%. At the same time, non-spiked chicken meatballs were prepared as control. At day 0, functionalised meatballs (PLF₀) exhibited a total polyphenol content of 10.44 mg GAE per g, significantly higher than controls (PB, 2.74 mg GAE per g). Antioxidant capacity, expressed as IC₃₀ against the ABTS˙⁺ radical, was 0.0127 mg mL⁻¹ in PLF₀ compared to 0.8982 mg mL⁻¹ in PB₀. After 5 and 10 days of storage at +4 °C, functionalised samples retained markedly higher antioxidant potential, with IC₃₀ values nearly 9-fold lower than PB₅ and 14-fold lower than PB₁₀, respectively. Cooking preserved these benefits: PLFC maintained a TPC of 9.33 mg GAE per g and an IC₃₀ of 0.1129 mg mL⁻¹, while controls showed lower TPC (5.54 mg GAE per g) and weaker activity (1.4920 mg mL⁻¹). Sensory evaluation revealed that the incorporation of functionalised pectin did not adversely affect the visual appearance, odor, or texture of chicken meatballs. Both raw and cooked products maintained comparable acceptability to controls, with no significant differences in overall liking. Notably, the functionalised meatballs retained their characteristic sensory profile after 10 days of refrigerated storage, confirming that the enrichment with coffee silverskin-derived conjugates did not impair consumer-relevant attributes. Overall, these results demonstrated that functionalisation of chicken meatballs with coffee silverskin extract enhanced the polyphenol content and the antioxidant stability while preserving desirable sensory qualities, making this approach a promising strategy for developing antioxidant-enriched meat products.