Physicochemical and proximate composition of MK 373, Abujachi and Makowchi groundnut varieties grown in Kwara State, Nigeria

Abstract

The analysis of the nutritional constituents of crops is of considerable importance especially if such analysis is centered on crops forming part of the diet of many people around the globe. One of such crops that is widely consumed around the world and also has many other forms of benefits for many people is the groundnut. Thus, this work seeks to examine the physicochemical and proximate compositions of MK 373 and two local varieties of groundnut (Abujachi and Makowchi) grown in Nigeria. To ensure precision and accuracy, these investigations were conducted following standardized protocols and methods. Compared to Abujachi (4.76 ± 0.19%), significantly low moisture content was recorded in MK373 (4.31 ± 0.26%) and Makowchi (4.42 ± 0.07%). Makowchi had the highest ash content (2.62 ± 0.08%) while MK373 had the highest crude fat (49.14 ± 0.42%). While MK 373 recorded highest protein, Makowchi ranked the highest in carbohydrate. Crude fiber content was not significantly different in the three varieties. Oil extract from these groundnut varieties were pale yellow and liquid at room temperature (25oC). Specific gravity at room temperature was 0.91 while refractive index ranged from 1.459 to 1.460. Saponification value was most noticeable for MK373 (193.62 ± 0.98 mg KOH/g), followed by Makowchi (189.22±0.31 mg KOH/g) and Abujachi (186.61±0.29 mg KOH/g). Makowchi had the highest percentage fatty acid and iodine values 12.83 ± 0.14% and 71.45 ± 0.20 mg/100g respectively, followed by Abujachi (12.65 ± 0.16%and 64.83 ± 0.10 mg/100g) and MK373 (7.83 ± 0.00% and 57.37 ± 0.21 mg/100g). These results suggest that the three oil extracts exhibited varying characteristics. It also showed the oil extracted from these groundnut varieties could be useful in industry in their crude form and safe for consumption when properly refined.