Sensory Evaluation of Ogiri Produced by Solid State Fermentation of Boiled Melon Seeds (Cucumis melo) in a Stainless Steel Fermentor

Abstract

Boiled melon seeds (Cucumis melo), wrapped in Thaumatococcus danielli were fermented for five days in a stainless steel solid state fermentor designed and fabricated by the Federal Institute of Industrial Research, Oshodi (FIIRO) Lagos, Nigeria. During fermentation, the amounts of soluble sugars and free amino acids present were estimated and the fermented mash was dried and milled into ogiri. Two Nigerian traditional soups oha and onugbu and a traditional yam pottage ikokore were prepared using the ogiri as a seasoning in each. Sensory analysis of the ogiri in the delicacies was carried out concurrently with samples purchased from the market (made from melon and castor seeds respectively) by a panel of tasters. The amounts of soluble sugars were observed to fluctuate during fermentation culminating in a peak (6.79 ± 0.07) at its end while the pH and free amino acids produced increased steadily (8.66 ± 0.01 and 98.67 ± 0.94) unto the end of fermentation. Results of the sensory evaluation showed the ogiri produced by the fermentation of Cucumis melo in the fermentor to compare favourably above that in the market and in the control experiments, ranking 1st and 2nd in oha and onugbu soups respectively and 1st in ikokore. Thus, the ogiri produced using the fermentor can be said to be more acceptable than the ogiri produced in an uncontrolled fermentation environment and hence the fermentor may thus be utilized to achieve a hygienic fermentation and also production of an acceptable ogiri having no obnoxious odour or taste.

Keywords: Solid state fermentor, onugbu soup, ikokore, aroma generation, sensory evaluation.