ABSTRACT

 The quality evaluation of biscuit produced from flour blends of avocado seeds and wheat was investigated. The proximate analysis, functional properties, physical properties, anti-nutrients (in flour and biscuit) and the sensory evaluation was carried out. The moisture content, ash, fat, and crude fibre of the composite biscuits increased with progressive increase in the proportion of avocado seed flour, with sample 355 (70%wheat: 30% avocado seed flour) having the highest value of moisture content (8.00%), ash (2.75%), fat (7.90%), and crude fiber (2.90%), respectively. The carbohydrate and protein were observed to decrease with increase in avocado seed flour proportion. The composite flour sample had higher water and oil absorption capacity compared to the control (100% wheat). The bulk density (0.71 g/ml), emulsion capacity (33.02 g/ml) and wettability (132.00 g/ml) of the control (100% wheat) was significantly higher (p<0.05) than those of the composite flour respectively. The control (100% wheat) thickness (0.73 mm) was higher and also had a higher diameter (4.16 mm) and breaking strength value (1480.50 mm), respectively. However, the composite flour blends had higher spread ratio (6.75 g) and weight (7.78 g) with sample 355(70% wheat: 30% avocado seed) scoring the highest respectively. low anti-nutrient were observed in the flour as the avocado seed flour proportion increased and these were tannin (1.97 to 2.24 mg/100 g), oxalate (0.51 mg/100 g), cyanogenic glucoside (1.63 to 2.20 mg/100 g), alkaloid (0.52 to 1.12 mg/100 g), phytate (1.33 to 1.85 mg/100 g) but were drastically reduced up on baking the biscuit (0.24 to 0.66 mg/100 g) tannin, (0.06 to 0.39 mg/100 g) phytate, (0.03 to 0.39 mg/100 g) oxalate, (0.40 to 0.64 mg/100 g) cyanogenic glucosides and 0.25 to 0.57 mg/100 g alkaloid for sample 355 (70% wheat: 30% avocado seed) which had the highest value. The sensory evaluation showed higher scores for 100% wheat flour sample in terms of appearance, taste, mouth feel and texture with significant difference (p<0.05) from the other samples. However, the overall acceptability showed no significant difference (p<0.05) in the wheat sample and sample 311(95% wheat: 5% avocado seed). Therefore, avocado seed flour can be used comfortably to produce nutritious biscuits that will be acceptable by consumers when incorporated in wheat up to the blend ratio used in sample 311 (95%wheat : 5%avocado seed flour).