Physicochemical and sensory properties of cookies produced from whole wheat and whole watermelon seeds flour blends

Composite flour was produced from whole-wheat flour (WWF) and whole-watermelon seeds flour (WWMSF) and its potential in producing cookies was investigated. Five samples were produced at WWF: WWMSF ratios of 100:00; 90:10; 80:20; 70:30 and 60:40. The proximate and functional properties of the composite flours and the sensory properties of the cookies produced from these flour blends were evaluated using standard methods. The proximate analysis results show that the moisture, ash, fibre, protein, and fat increased from 6.60 – 7.42%; 1.99 – 2.78%; 3.20 – 3.57%; 10.51 – 16.88%, and 5.40 – 21.97% leading to a decrease in the carbohydrate content from 72.30 – 47.38% respectively as the level of WWMSF substitution increased in the blends. Moisture content in the range of 6.60 – 7.42% fell far below the 14% recommended for shelf-stable storage of flour products. The 60% WWF: 40% WWMSF had the highest energy value of 454.77 kcal. There was a significant reduction in all the functional properties assessed as WWMSF increased in the blends from 0.78 – 0.73g/ml (bulk density); 160.00 – 138.65% (Water absorption capacity); 122.84 – 116.00% (Oil absorption capacity) and 6.85 – 4.62% (swelling capacity). However, the sensory evaluation results show that cookies produced from 100%WWF were ranked highest in terms of colour (6.10); taste (6.20), and general acceptability (6.80). However, no significant difference exists among the cookies produced up to 20% substitution level in all the sensory attributes; showing the potential of whole wheat and whole watermelon seeds flour blends in the snack industry.