NUTRIENT EVALUATION OF DIFFERENTLY PROCESSED JUJUBE (Ziziphus mauritiana Lam.) FRUIT AS A POTENTIAL FISH FEED INGREDIENT

Abstract

High cost of fish feed has been a limiting factor for aquaculture development, hence, the need for continuous research efforts to identify affordable and nutritionally adequate alternative ingredients. This research was carried out to examine the nutritional quality of the raw and processed fruits of Jujube (Ziziphus mauritiana) as a potential fish feed ingredient. The jujube fruits were subjected to different treatments including soaking, boiling, toasting and fermenting following standard methods. The raw and processed fruit meals were then evaluated for proximate, amino acids and fatty acid composition. The results showed that all the processing methods led to increase ash content, crude protein and ether extract. The crude protein was increased from 14.05% in the control (raw) to 17.99 in the fermented Z. mauritiana. Toasting led to the better enhancement of the essential amino acids, especially the limiting ones like lysine that was increased to 1.13% from 0.74% in the raw fruit meal powder. Boiling appears to be the best treatment for the non-essential amino acids. Some of the fatty acid compositions were also influenced by the processing methods. Fermentation increased Omega 6 fatty acids from 2804.4mg/100g in the control to 3078.47mg/100g. The highest total fatty acid was also reported in the fermentation method. Jujube fruit seed meal has good nutritional quality that could make it suitable as a fish feed ingredient, while toasting and fermentation showed more improvement and they are recommended as the preferred processing methods for enhancement of the nutritional quality of Z. mauritiana.