Application and optimisation of ph-shift and ultrasound method for extraction of bioactive compounds from fish mince

The purpose of this study was to extract the bioactive compounds (peptides) from the fish mince of Indian anchovies (Stolephorus indicus) using novel technologies like Ultrasound-Assisted Extraction and pH-shift assisted extraction, and to optimise the process parameters for improved quality, yield and bioactivities. Although fish is a significant source of high-quality protein, most of the catch, especially tiny and low-value fish, is frequently discarded or underused. One practical method to increase the value of these raw materials and lessen environmental waste is to turn them into ingredients in functional food, cosmetic, medical applications, etc. Novel extraction technologies are not just scientific innovations; they are strategic necessities for modern food systems. They are transforming the raw materials by enabling higher yields of several components without damaging their nature, enhancing better functional properties, and sustainable use of by-products. pH-shift and Ultrasound-assisted extraction methods were used in this study as it is a gentle and effective technique that aids in the breakdown of proteins into smaller peptides, with enhanced functionality and bioactivity. The raw ingredient was fresh anchovy fish that had been washed and minced. Then the pH-shift method was used for the extraction of protein and bioactive components from fish mince after determining the solubilising and precipitating pHs (isoelectric point). Then proximate analysis was carried out for the extracted protein. The extracted protein was also applied for hydrolysis and degree of hydrolysis and antioxidant activities were analyzed. For improved stability, the sample was turned into a powder using spray drying. The disintegration of proteins into smaller peptides was validated by further characterisation techniques using FTIR. To determine their impact on of sample in ultrasound assisted extraction, different substrate-to-water ratios, including 1:5, 1:10, 1:15, and 1:20, were investigated in amplitudes 35, 50, and 65 %. The protein and peptide extraction was assessed by Lowry’s method. The DPPH, ABTS, and FRAP tests were used to assess antioxidant activities in the extracted samples. The results indicated that the samples show high protein extraction and strong antioxidant qualities, which suggested the production of bioactive peptides. Overall, this study shows that Indian anchovy mince can successfully be used to extract bioactive compounds (peptides) with good functional and antioxidant properties. The process also supports sustainable utilisation of fish resources by converting low-value materials into valuable products.