Selected Chemical Composition and Acceptability Assessment of Pre-treated Dehydrated Telfairia Leaves

Telfairia leaves were harvested fresh, sliced and subjected to different blanching pre- treatments tests - in boiling water, steam, sodium chloride and sodium bicarbonate solutions before drying in a multipurpose produce drier (40-500C) for preservation. The control portion was dehydrated without any pre-treatment. All the dehydrated test portions were analyzed for proximate composition (moisture, crude protein, crude fat, crude fibre, ash and carbohydrate), microbial quality and sensory acceptability assessments. Dehydrated steam-blanched and water- blanched leaves had relatively lower moisture content (13.75 – 13.99%). Leaf nutrients (crude protein, crude fat and ash) concentrated relatively more in the steam blanched dehydrated leaves. No microorganism was detected in all the dehydrated treated and untreated test portions. Process treatments reduced the sensory acceptability rating of the dehydrated leaves as the untreated control portions were better accepted by assessors. Keywords: Telfairia leaves, Blanching, Dehydration, Acceptability

Ascorbic acid retention of freshly harvested seven Nigerian green leafy vegetables after soaking in water

Vitamins are micronutrients needed in the body for important biologic functions. The current study examined the influence of steeping on vitamin C retention of seven Nigerian vegetable leaves after soaking for 8 h. One kilograme each was purchased and 6 lots of 100 g were sorted out, cleaned and treated as follow; whole leaf 1, whole leaf 2, sliced leaf 1, sliced leaf 2, sliced and salted leaf 1 and sliced and salted leaf 2. Each of the treatments 1 was soaked in 1 litre of distilled water while each of treatments 2 was soaked in 2 litres of distilled water. All treatments were kept for 8 h while monitoring the trend of reduction in vitamin C contents at 2 h intervals. Moisture (%) was determined following AOAC (2002) methods while dry matter content was estimated from moisture by calculating the difference. Ascorbic acid content (mg/100 g) was determined following the method of Ndawula et al. (2004). Result showed that; moisture, dry matter, and ascorbic acid contents of raw leaves ranged from 67.63–86.70%, 13.30–32.37%, and 103.00–1199.23 mg/100g respectively. During soaking, ascorbic acid retained by the seven green vegetables reduced as follows; 73.39–24.26% (Amaranthus viridis), 100.26–19.62% (Gnetum africanum), 129.05–27.72% (Gongronema latifolium), 66.84–7.55% (Ocimum gratissmum), 42.59–4.14% (Piper guinense), 77.38–10.26% (Pterocapus mildbedii) and 120.02–17.97% (Telfaria occidentalis). The study showed that ascorbic acid retention (%) of seven Nigerian green vegetable leaves decreased with increasing soaking duration