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The effect of moisture content variation on the characteristics and oil yield of tiger nut (Cyperus esculentus) seeds was investigated. The oil was extracted using the Soxhlet method at 9.5%, 20%, 30% and 40% moisture content for sample A, B, C and D respectively. The extracted oil was characterized using standard methods. The result showed a percentage oil yield of 25.89%, 19.05%, 12.48% and 12.14% for sample A, B, C and D respectively. The viscosity (mm2/s), specific gravity and smoke point ranges from 0.53-2.27, 0.91-0.84, and 231-215 respectively. The saponification value (mg/KOH/g), iodine value (g/100g) and acid value (mg/KOH/g) are 143.06, 185.13, 260.87, 294.52; 72.00, 88.45, 85.60, 88.45 and 3.37, 30.86, 65.90, 71.81 for sample A, B, C and D respectively. The peroxide value (m/mol/kg) and free fatty acid (mg/KOH/g) ranges from 2-21 and 6.73-143.62 respectively for the extracted oil at moisture content range of 9.5-40%. Moisture content has no effect on the refractive index of tiger nut oil; the high free fatty acid value indicates its edibility. It can be concluded that oil yield decreases with increase in moisture content, with the highest oil yield obtained at 9.5% moisture content. Therefore, an initial seed moisture content of 9.5% is recommended for the extraction of oil to obtain maximum oil yield. The oil can be use as lubricant, cooking as substitute for other vegetable oil and good for soap making. [ABSTRACT FROM AUTHOR]

The effect of packaging materials and storage duration on the nutritional composition of moringa olierfera leaves powder was investigated with a view to ensure its quality retention. Fresh moringa oleifera leaves were defoliated, washed in saline water, rinse in sterile water, drained and dried at ambient room conditions. Drying was concluded when weight of the sample remained constant at three consecutive reading. The dried sample was then milled and sieve into 0.5 mm - 1.0 mm particle size powder using a sieve. With the initial nutritional properties of the moringa oleifera powder determined, the samples were packaged in a sterile glass jar, plastic jar and polyethylene bag and stored at ambient room conditions. The packaged samples were analysed monthly for nutritional properties for three months at three replicates. The experiment was carried out using a randomized block design of 3 packaging types x 3 months storage duration at 3 replicates (3 packaging types x 3 storage duration x 3 replicates = 27 samples). The nutritional properties were determined using standard methods. The results showed that there are no significant differences (P=0.05) in moisture content, crude protein and sodium of all the package samples. Sample packaged in glass jar had the highest carbohydrate (43.53%), vitamin E (11.08 mg/g) and zinc (9.41) while the sample packaged in polyethylene bags had the lowest carbohydrate content (42.05%), ash content (10.30%) and zinc content (8.16mg/g). The moisture, crude fibre and carbohydrate content of the samples in each of the packaging materials were observed to decrease with increase in storage duration. Moringa leaves powder stored in glass and plastic jar had significantly higher crude fat (3.35 - 4.81%), crude protein (25.34-28.81 %) and ash (10.93-11.28 %) as storage duration increased. [ABSTRACT FROM AUTHOR]