Dragon fruit (Hylocereus undatus) peel as antioxidant dietary fibre on quality and lipid oxidation of chicken nuggets.

In this study, the efficacy of dragon fruit peel (DFP) powder as antioxidant dietary fibre (ADF), at two different concentrations (T1-1.5% and T2-3.0%), on quality improvement and susceptibility to lipid oxidation of chicken nuggets during 20 days of refrigerated storage was assessed. DFP, rich in dietary fibre (56.91%) with higher insoluble dietary fibre, phenolics (36-39 mgGAE/100 g) content and possessing good radical scavenging activity as well as reducing power, contained 10.36% protein, 4.48% fat and 2.34% ash. HPLC analysis revealed presence of high concentrations of gallic and ferulic acid, among the phenolics. Incorporation of DFP in nuggets although decreased the pH but improved emulsion stability as well as cooking yield and had higher protein, ash and lower fat content. Further, the treated nuggets had significantly (p < 0.05) higher dietary fibre and total phenolics content than control. Incorporation of DFP decreased the hardness, gumminess and chewiness and improved (p < 0.05) the products' redness values. Sensory evaluation of the products revealed significant improvement in the appearance score and non-significant (p > 0.05) increase in the scores of other attributes compared to control samples. DFP significantly decreased lipid peroxidation, odour scores and microbial load in chicken nuggets during 20 days of storage period. From the study, it could be deduced that DFP rich in bioactive components had positive influence on the nutritional quality of chicken nuggets and could also be used as ADF in muscle food without affecting the quality and acceptability of products.