QUALITY ATTRIBUTES OF SNACK BARS FROM ACHA, AFRICAN YAM BEAN AND DATE

Abstract

ABSTRACT Micronutrient deficiencies which are a major issue in many developing nations, permanently impair the physical and mental development of growing children and pregnant mothers. Consuming foods high in naturally occurring compounds like vitamins, minerals, and antioxidants has been shown to boost the immune system. The objective of this study was to assess the quality attributes of snack bars from indigenous food flours; namely, acha (A), African yam bean (AY), date (D) and turmeric. Simplex Centroid mixture design for three independent variables was used to obtain the various ingredient combinations and fourteen experimental runs was generated to investigate the effect of flour blend formulation (25-40% AY, 15-30% A, 45-60% D) on some quality attributes of the snack bars. Data from the experimental runs were analysed using one way ANOVA, regression model and numerical optimisation. The snack bars were analysed for moisture (MC), fat (FC), fibre (FIB), ash (AC), protein (PC), carbohydrate (CHO), iron (FE), zinc (ZN), vitamin B9 (VB9), vitamin C (VC), colour and texture profile using standard laboratory procedures. The range of mean values for MC, FC, FIB, AC, PC, CHO, FE, ZN, VB9, and VC were 13.17–16.44%, 3.78–13.68%, 2.44–6.52%, 2.17–3.33%, 9.05–33.52%, 32.13–64.82%, 0.06–0.11 mg/100g, 0.2–0.32 mg/100g, 4.47–6.82 mg/100g, 3.33–8.11 mg/100g respectively. Numerical optimisation technique was used to obtain the optimum blend of AY40A15D45 and AY25A25.33D49.67 with desirability of 0.777 and 0.537 respectively. The optimised snack bars were analysed for amino acid profile [valine (4.17, 3.84g/100g), threonine (3.01, 2.64g/100g), isoleucine (4.07, 3.35g/100g), leucine (7.37, 6.64g/100g), lysine (3.35, 3.55g/100g), methionine (1.35, 1.25g/100g), phenylalanine (3.92, 4.37g/100g), histidine (2.33, 2.22g/100g), tryptophan (0.76, 0.68g/100g), glutamic acid (11.61, 11.01g/100g), glycine (3.28, 3.42g/100g), alanine (4.58, 4.03g/100g), serine (3.54, 3.09g/100g), proline (3.78, 3.21g/100g), aspartic acid (7.08, 6.57g/100g), arginine (5.16, 4.33g/100g), tyrosine (3.29, 2.71g/100g), cysteine (1.24, 0.95g/100g)], 2,2-Diphenyl-1-picrylhydrazyl (76.67, 81.16%), ferric ion reducing antioxidant power (1.46, 1.52), vitamin B1 (0.66, 0.66 mg/g), B2 (1.14, 0.28 mg/g), E (2.54, 3.29 mg/g), B9 (9.35, 9.89 mg/g), C (10.47, 11.37 mg/g), potassium (2.23, 1.69 mg/100g), sodium (1.51, 1.29 mg/100g), calcium (0.98, 1.38 mg/100g), magnesium (0.61, 0.81 mg/100g), phosphorus (32.18, 36.16 mg/100g), iron (1.61, 1.89 mg/100g), and zinc (1.47, 1.28 mg/100g) respectively in addition to proximate analysis; MC 11.82, 13.63%, FC 8.81, 11.02%, FIB 9.28, 10.31%, AC 1.21, 1.23%, PC 22.52, 18.43% and CHO 46.33, 45.38% respectively, colour (lightness 20.81, 20.62; redness 5.40, 5.79; yellowness 5.82, 4.85), texture profile analysis; hardness (231.75, 314.25N), chewiness (213.00, 294.50), stringiness (7.76, 7.20), resilience (0.02, 0.02), gumminess (221.00, 302.51), springiness (0.96, 0.98) and cohesiveness (0.94, 0.95) respectively. The optimised snack bars had overall acceptability of 6.58 and 6.68 respectively. In conclusion, snack bars made from the optimum ratio of African yam bean, acha, dates and turmeric have an improved nutritional composition due to their richness in micronutrients, which helps reduce micronutrient deficiency while improving consumers' health by providing a more nutrient-dense snack option.