Unlocking functional potential of flaxseed ( <i>Linum usitatissimum</i> L.) protein isolates through enzymatic defatting and microwave-induced structural remodeling

The study aims to enhance the functional properties of flaxseed protein isolates using enzymatic defatting and microwave-assisted structural modification. The research focuses on improving the physicochemical and techno-functional characteristics of the proteins to increase their suitability for food and nutraceutical applications. Flaxseed protein isolates were extracted from conventional, Soxhlet and enzymatic flaxseed meals. The amino acid composition of raw flaxseed flour and its different protein isolates, as well as its functional properties viz. solubility, emulsifying properties, water holding and oil absorption properties, were determined. The extracted protein isolates were also subjected to microwave modification, and changes in functional properties due to modification were recorded. The highest yield and recovery of protein isolates were found from conventional meal which was 21.32 ± 0.32% and 78.10 ± 0.24%. Flaxseed protein was found to be rich in isoleucine (1.81 ± 0.22 g/100 g), serine (1.63 g/100 g) and glutamic acid (1.04 ± 0.26 g/100 g). The functional properties of flaxseed were found to be affected by changes in pH. The highest emulsion stability of flaxseed protein isolates was observed at pH 10 and the lowest at pH 4, which is near its isoelectric point. The turbidity of flaxseed protein at different pH values showed that proteins from Soxhlet meal had high turbidity, which further increased after microwave modification.