Incorporation of phenolic extracts from different by-products in yoghurts to create fortified and sustainable foods

This work aimed to study and compare the effect of the incorporation of agro-industrial by-products(chestnut shell,grapeseed,and pomegranate peel)into yoghurts to fortify them while assessing their potential to replace synthetic preservatives.From each by-product,phenolic extracts were obtained and characterized.All extracts demonstrated antioxidant and antibacterial properties,and the capacity to inhibitα-amylase.Chestnut shell extract stood out regarding antioxidant capacity,displaying values of 1128 and 972 mgT_(rolox•gextract)^(-1),for the assays with DPPH and ABTS,respectively.Ten yoghurts were produced(negative control,positive control with 0.1%of sorbic acid,two for each extract with 0.1%and 0.2%of extract,a mixture of extracts and a mixture of extracts with sorbic acid),and stored at 4℃.The incorporation of the extracts into the yoghurts maintained their physical-chemical properties and microbiological safety.The samples inhibited the growth of Escherichia coli and Staphylococcus aureus.Oxidative analysis proved that higher concentrations of extract had similar results to synthetic antioxidants.The results showed the viability to fortify yoghurts with the incorporation of by-product extracts,developing a value-added food.Furthermore,revealed the possibility of these extracts replacing synthetic preservatives and antioxidants.