The use of immobilised digestive lipase from Chinook salmon (Oncorhynchus tshawytscha) to generate flavour compounds in milk

•Milk lipids were selectively hydrolysed by immobilised salmon lipase in a reactor.•The batch reactor was run for nine cycles with stable activity for eight cycles.•The lipase showed the highest specificity towards short-chain fatty acids.•Hexanoic acid was released in the highest amounts.•This system has potential uses in developing dairy products with unique flavours. The aim of this research was to determine the potential of immobilised digestive lipase from Chinook salmon (Oncorhynchus tshawytscha) to generate flavour compounds in milk. The lipase was immobilised on hydrophobic resin (Toyopearl® Butyl) and used to hydrolyse milk lipids in a batch reactor. The lipase was stable when immobilised and there was no significant resin fouling or enzyme inhibition between cycles. Eight cycles were achieved before the hydrolysis rate dropped significantly because of physical losses of the immobilised lipase. The immobilised lipase showed the highest specificity towards short-chain fatty acids butanoic and hexanoic acids, the main dairy product flavour and odour compounds. Based on the performance of the reactor, and the ability of the lipase to alter free fatty acid composition and sensory characteristics of milk, the immobilised salmon lipase has potential applications in developing dairy products with unique flavours.