Nutritional value of Shea Butter (Vitellaria paradoxa) seed Meal (SBSM) as affected by different days of Natural fermentation

Abstract

A laboratory studies were carried out to investigate the effect of fermentation duration on nutrients and antinutrient composition of shea butter seed meal, SBSM. 500g of the wet unprocessed SBM was cooked for 1 hour after which it was cooled and divided into 5 portions. The first portion was tagged T1 and oven-dried. The remaining 4 were bagged in different air-tight polythene bags and allowed to ferment for 3, 4, 5 and 6 days and each treatment was labeled as T2, T3, T4 and T5, respectively. At the end of the processing, each treatment was replicated and the samples analyzed. Crude protein and ether extract were significantly (P<0.05) improved as the days of fermentation increased. The values increased from 10.33 and 2.76% to 15.58 and 4.50%, respectively at day 3 fermentation. However, the values reduced as fermentation entered day 5 and 6. Fermentation of SBSM for up to day 4 (T5) and 5 (T6) gave the best (P<0.05) result for crude fibre (14.37 and 14.78%), whereas fermentation for as early as 3 days gave same result for ash as compared to those of day 4 (4.48%), 5 (3.29%) and 6 (3.11%), respectively. Similarly, fermenting SBSM for up to 4 days gave significantly (P<0.05) the highest value for gross energy (3.13 kcal/kg) whereas that of day 5 produced the highest value of NFE (63.51%) but similar to that of day 2 (61.98%). There was no significant (P>0.05) variation in the value recorded for DM across the treatments. Consistently, the best (P>0.05) result obtained for all the minerals evaluated were on the fourth day of fermentation except for days 3 (0.06%) and 6 (0.04%) which were comparable to both the control (0.09%) and day 4 (0.09%). Fermenting SBSM for up to day 4 gave the best (P>0.05) result for potassium (0.36%), calcium (0.18%) and phosphorus (0.36%). However, the treatment did not (P<0.05) affect the concentration of magnesium. Saponin and phytic acid were significantly (P<0.05) reduced due to fermentation for 3 to 4 days but were increased (P<0.05) beyond this duration of fermentation. However, there was no variation (P>0.05) in the results obtained for tannin (0.001 – 0.003%), oxalate (0.0010 – 0.0014%) and flavonoids (0.005 – 0.006%). The vitamins analyzed namely A, B6 and α- tocopherol were consistently improved (P<0.05) from the beginning of the time of fermentation up to day 4 but reduced (P<0.05) beyond this period of fermentation. Monogastric animal farmers can therefore, ferment SBSM for at most 4 days and conveniently feed their animals as a replacement for conventional energy source.