Effect of microwave-assisted treatment on proximate, techno-functional, thermal, structural and storage properties of tiger nut (Cyperus esculentus L.) flour.

BACKGROUND: The use of an emerging technique of microwave-assisted roasting on tiger nut flour was investigated. Tiger nuts were submitted to microwave irradiation at 450, 600 and 900 W each at 5, 10 and 15 min and milled to flour. The flours were analyzed for proximate, bioactive, techno-functional, morphological, thermal and storage composition, while the untreated sample represents the control.

RESULTS: Results obtained revealed that microwave treatment significantly (p < 0.05) elicited varied modifications in the proximate composition and techno-functional properties. However, the treatment improved the bioactive composition of phenolic content together with the antioxidant activity of the flour. Progressive microwave treatment of tiger nuts (TGN) resulted in flours with darker colors and reduced pasting parameters. Structural modification of starch granules, protein denaturation and starch-protein complexes occasioned by microwave treatment was evidenced in the functional group analysis, morphological agglomeration, increased particle size and thermal properties. Furthermore, treatment enhanced the microbiological qualities of flour after 8 weeks of storage.

CONCLUSION: The significance of this study shows that microwave treatment offers an excellent physical modification to the nutritional, functional, sensory, colour properties and safety attributes of tiger nut flour for increased food application. A development which could present potential opportunities in novel food formulation by food and agro-inclined industries. This article is protected by copyright. All rights reserved.