Effects of cold storage and storage over fireplace on the rheological functions of “Ogbono” (<i>Irvingia gabonensis</i>)

Abstract

The rheological functions of flour of the two varieties (Irvingia gabonensis and Irvingia wombolu) kernels were studied. The kernels were stored under cold storage and over fireplace and analysed fortnightly for a period of three months. The result showed that cold storage significantly (p<0.05) increased the emulsion capacity of flour of I. Gabonensis and I. Wombolu after the second week of storage; no significant change occurred from 6^th to 8^th week of storage, after which there was a significant increase. While storage over fire place increased significantly the emulsion capacity of I. Wombolu after the fouth week of storage and after the second week of storage for I. gabonensis. The oil absorption capacity of flour of both varieties did not change significantly (p<0.05) throughout the storage period for cold storage while for storage over fireplace the oil absorption capacity increased significantly after the second week of storage for I. gabonensis but remained unchanged for I. wombolu. The water absorption capacity decreased significantly for both varieties stored under cold storage and increased significantly for both varieties stored over fireplace. The viscosity of I. wombolu did not change significantly (p<0.05) under the two storage conditions throughout the storage period. However for I. gabonensis the viscosity changed after the second week in both storage conditions; after which there was no significant change observed in the storage over fire place; but for cold place storage there was no significant change from 2^nd to the 8^th week; after which there was an increase on the tenth week. The results suggest that cold storage and storage over fireplace retains the oil absorption capacity of both varieties and viscosity of I. wombolu when stored for a period of 10 weeks.

Keywords: “Ogbono”, cold storage, rheological functions, fireplace

Nigerian Food Journal Vol. 23 2005: 47-52