Vitamin A retention in \"palm oil-gari\" during processing and storage

Abstract

Gari samples from six different locations in Imo state of Nigeria, were assessed for vit A activity for a period of 4 weeks. Five samples were randomly selected from each location and stored at 28°C under the usual household storage conditions. Gari sample enriched with vit A stored for 6 weeks under similar conditions but kept in a tightly covered amber coloured bottle, to minimize contact with oxygen and light, was also assessed. The initial status of vit A activity (IU/100g) ranged from 183-723 in location A; 33.3-906 in B; 93-143 in C; 51.2-71.1 in D; 37.5-39.5 in E and 13.2-59.2 in F. The result showed remarkable losses in activity during storage. All the samples in locations A, B and E recorded over 25% loss in activity after the 2nd week of storage and over 50% by the 3rd week of storage. Samples from location F showed very poor retention of vitamin A and less than 10% activity was detected at the end of the 2nd week. Vitamin A activity of the enriched palm oilgari (EPOG) having an added level of 40,000 IU/100g, decreased to 992 IU/100g immediately after toasting. However, the EPOG showed only 7% loss in activity after a storage period of 6 weeks. The result of this study suggests that vit A retention in the traditionally processed palm oil-gari is very poor and the usual storage conditions may enhance further losses. However the enriched palm oil-gari stored under conditions that reduce contact with light and oxygen exhibited greater vit A retention.

Keywords: vitamin A retention, palm oil, gari

Nigerian Food Journal Vol. 23 2005: 69- 73