Assessment of the Quality of Locally Produced Groundnut Oil from Smallholder Processors in Kano State

Groundnut oil is the most widely produced edible oil from indigenous sources in northern Nigeria, particularly in Kano State where extensive smallholder groundnut processing exists. However, quality inconsistencies among small-scale producers remain a challenge for consumer safety and market credibility. This study assessed the physicochemical quality and food safety compliance of locally produced groundnut oil from twenty smallholder processors across three zones of Kano State, namely Kano Municipal, Bichi, and Wudil. Oil samples were collected in sterile amber bottles and transported to the laboratory under controlled conditions. Parameters assessed included free fatty acid content, peroxide value, saponification value, iodine value, refractive index, specific gravity, colour, and aflatoxin concentration. Analyses followed Association of Official Analytical Chemists and Codex Alimentarius methods. Results revealed that 55 percent of samples exceeded the Nigerian Industrial Standard free fatty acid limit of 2 percent, with values ranging from 1.4 to 6.8 percent. Peroxide values were elevated in 40 percent of samples. Aflatoxin B1 was detected in 30 percent of samples, with three exceeding the 10 micrograms per kilogram Nigerian regulatory limit. Processing conditions, specifically the use of damaged groundnut seeds and delayed processing after shelling, were the primary quality risk factors. Targeted training and quality control input support are urgently recommended for smallholder groundnut oil processors in Kano State. Keywords: groundnut oil, physicochemical quality, aflatoxin, smallholder processors, Kano.