Textural and sensory properties of trifoliate yam (Dioscorea dumetorum) flour and stiff dough 'amala'

J Food Sci Technol (May 2015) 52(5):28942901 DOI 10.1007/s13197-014-1313-y

ORIGINAL ARTICLE

Textural and sensory properties of trifoliate yam (Dioscorea dumetorum) flour and stiff dough amala

O. A. Abiodun & R. Akinoso

Revised: 26 July 2013 /Accepted: 6 March 2014 /Published online: 23 March 2014 # Association of Food Scientists & Technologists (India) 2014

Abstract The use of trifoliate yam (Dioscorea dumetorum) flour for stiff dough amala production is one of the ways to curb under-utilization of the tuber. The study evaluates the textural and sensory properties of trifoliate yam flour and stiff dough. Freshly harvested trifoliate yam tubers were peeled, washed, sliced and blanched (60C for 10 min). The sliced yam were soaked in water for 12 h, dried and milled into flour. Pasting viscosities, functional properties, brown index and sensory attributes of the flour and stiff dough were analyzed. Peak, holding strength and final viscosities ranged from 84.09 to 213.33 RVU, 81.25 to 157.00 RVU and 127.58 to 236.17 RVU respectively. White raw flour had higher viscosity than the yellow flours. The swelling index, water absorption capacity and bulk density ranged from 1.46 to 2.28, 2.11 to2.92 ml H2O/g and 0.71 to 0.88 g/cm3 respectively. Blanching method employed improved the swelling index and water absorption capacity of flour. The brown index values of flour and stiff dough ranged from 6.73 to 18.36 and 14.6346.72 respectively. Sensory evaluation revealed significant differences in the colour, odour and general acceptability of the product when compared with the stiff dough from white yam.

Keywords Amala . Blanching . Pasting viscosity Sensory analysis . Stiff dough . Trifoliate yam

Introduction

Yam is an important food in many tropical countries particularly in West Africa, South Asia and Caribbean, where it also has a social and cultural importance for about 300 million people throughout the world (Manuel et al. 2005; Ettien et al. 2009). Total world production of yam had been estimated to be 40 million tonnes per year while Nigeria (the leading producer) produced 34 million tonnes which accounts for69.8 % of the yam (FAO 2006; IITA 2007). Yam flour production is a way of preserving yam tubers in a storable form so as to make it available during the off season (Oni 2006), thereby reducing storage losses as well...