Amelioration of tiger nut insoluble dietary fiber as a partial substitute for fat in meat emulsions: Techno-functional properties and in vitro protein digestibility

Abstract

The effects of tiger nut insoluble dietary fiber (TNF) (1%-3% w/w) on techno-functional properties and in vitro protein digestibility of low-fat meat emulsions were examined. The results showed that TNF (especially 2% and 3%) could improve techno-functional performances of low-fat meat emulsions in terms of water binding capacity and textural attributes, which were even preferable to the high-fat control. The improvements were associated with the attenuated fluidity of inner water within the gels, the increased storage modulus (G′), the formation of a well-joined gel network with uniformly-dispersed fat particles and the uncoiling of α-helix and the formation of β-sheet. The weakened water mobility, the heat-triggered conformational shift from α-helix to β-sheet, as well as less and evenly distributed fat particles ulteriorly led to elevated protein digestibility in meat emulsions. Therefore, TNF shows promise as a fat substitute to develop fat-reduced emulsified pork meat products with desirable quality and digestion behaviors.