Effect of microwave treatment on cooking time, colour, sensory and nutritional properties of Bambara groundnut (Vigna subterranea)

Abstract

Bambara groundnut is a leguminous crop that currently experiences a low level of utilisation because it is hard-to-cook and difficulty to dehull. In this study, the effects of different microwaving power of 450, 500, 600 and 750 W and time (0, 30, 60, 120 and 240 s) on cooking time, colour, sensory and nutritional properties of Bambara groundnut using standard methods were investigated. Microwaving generally reduced the cooking time of Bambara groundnut. The cooking time reduced by approximately 28, 46, 52 and 55% when Bambara groundnut was microwaved at 450, 500, 600 and 750 W for 240 s, respectively. Microwaving did not significantly (p>0.05) affect the colour and appearance of the grain. Bambara groundnut had similar lightness values (60.66-63.15), but slightly different a (3.38-5.57) and b values (16.16-19.20) after microwaving. Protein (23.90-26.88%) and carbohydrate (47.85-58.58%) were the major components of raw and microwaved grains. Microwaved grains showed higher digestibility values (approx. 78-85%) compared to the raw Bambara groundnut (approx. 71%). Mean sensory scores revealed that Bambara groundnut microwaved at 600 W for 240 s had comparable acceptability with the control sample. Microwaving can be used to reduce cooking time of Bambara groundnut, improve protein content and digestibility without significantly altering the sensory properties.

Preference for improved varietal attributes of Bambara groundnut among smallholder farmers in Ghana

“…There is extensive literature on the nutritional superiority of Bambara among other legumes (Brough & Azam-Ali 1992;Okpuzur 2010;Gqaleni 2014;Mubaiwa et al 2018b;Temegne Nono et al 2018;Oyeyinka et al 2020;Hlanga et al 2021). In addition to the ability of the crop to thrive under harsh environmental conditions, it also serves as an alternative to animal protein and a source of income for most rural dwellers and smallholder farmers (Hillocks et al 2012).…”

“…Current research and development efforts have focused on nutritional quality, agronomic improvement, seed quality, etc. (Mubaiwa et al 2018a;Mandizvo & Odindo 2019;Oyeyinka et al 2020;Tan et al 2020;Hlanga et al 2021), with little effort being made to focus on the demand side to assess the preferences of consumers and, subsequently, the adoption of improved varieties. Accordingly, there have been minimal development efforts regarding the crop, resulting in very few improved varieties and hence low rates of adoption (Adzawla et al 2016;Tan et al 2020).…”

Phytotomy of ten accessions of Vigna subterranean (L.) Verdc

“…Seeds can be ground to make flour [6]. Ripe seeds are hard and a longer period of time is required for it to be cooked properly than those of other legumes [19]. Large seeds are more accepted than smaller ones, specifically use as a snack [20].…”