Influence of jack bean (Canavalia ensiformis (L) DC) milk processing on bioactive compounds and its antioxidant activity

Abstract

To seek a possibility of jack bean (Canavalia ensiformis (L) DC) utilized as a food, the development of jack bean milk processing was investigated. The processing steps included boiling, soaking, grinding and heating. The raw beans, boiled beans, soaked beans, extracted liquid and separated solid were all freeze dried. Those samples were evaluated for total phenolic content (TPC), total flavonoid content (TFC), and DPPH free radical scavenging activity, compared to those of the raw materials. The increase in TPC and TFC during bean boiling observed, and estimated due to the liberation of phenolics by the destruction of chemical bonds in cell matrix, physical destruction of the matrix by heat treatment observed by SEM results reported in this study. This mentioned that some phenolics existed as a bonded component. Decreasing of TFC was observed in the soaking step due to the migration of the compounds into soaking water. UHPLC-MS-MS based multivariate analysis showed grouping of phenolic compounds present in methanol extracts of the dried samples, mentioning its changes during processing. Kaempferol glucosides detected and quantified in this study, play an important role in the changes. The considerable concentrations of them in jack bean milk, lead to the development of functional drink.

Keywords:
antioxidant; jack bean milk; bean milk processing; flavonoid; kaempferol glycoside