Development of a novel yoghurt enriched with fermented edible bird’s nest: Physicochemical, antioxidative, and microbiological stability

The exploration of novel functional ingredients to improve yoghurt quality characteristics and expand its functional potential is an active area of research. Fermented edible bird’s nest (EBN), rich in bioactive compounds, presents significant yet underexplored potential as a value-added ingredient in yoghurt development. This study aimed to develop a novel yoghurt formulation using fermented EBN and evaluate its physicochemical, antioxidative, and microbiological stability during storage. To achieve this, yoghurt formulations incorporating different levels of EBN fermented with Latilactobacillus curvatus (EBNLC) were prepared. The shelf-life stability of the prepared yoghurts was assessed by comparing the novel formulations with control yoghurt (Yc) and yoghurt enriched with EBN hydrolysate (Yhydro) over five weeks of storage. It was found that yoghurt containing 5.25 % of EBNLC (YF1) demonstrated the most similar characteristics to Yc, with no significant difference (p ≥ 0.05) in pH, total titratable acidity, total soluble solids, colour, firmness, syneresis, aerobic colony count, total coliform count, yeast and mould count, and total Salmonella count. The half-life of YF1 based on apparent viscosity and firmness was 8.87 and 5.71 weeks, respectively, following a zero-order kinetic model for degradation. Principal component analysis (PCA) of the yoghurt samples revealed that 93.92 % of the total variance was explained by the first two principal components, with FRAP activity and syneresis playing prominent roles in differentiating the sample groups. Despite observed quality changes during storage, microbiological stability remained high. These findings suggest that fermented EBN may support the stability and overall quality of yoghurt during storage, paving the way for the development of new functional yoghurt products.