UNILORIN researchers recommend stainless steel machines in food processing
By Mustafa Abubakar
Researchers from the University of Ilorin have recommended the urgent adoption of stainless steel for fabricating food grinding machines and the introduction of contactless grinding technology as measures to prevent the silent but dangerous contamination of food consumed daily by millions of Nigerians.
Speaking with UNILORIN Bulletin penultimate Wednesday (September 17, 2025), the Principal Investigator (PI) of the study, Prof. Suleiman AbdulKareem, disclosed that the team, also want stronger government intervention through the establishment of safety standards and policies, as well as public enlightenment to educate both machine operators and consumers about the health risks associated with locally ground foods.
According to him, the research explained that grinding discs, mostly made from cast iron, undergo deterioration during use, releasing microscopic metallic fragments into food.
They also advised that stainless steel should be used in machine fabrication to reduce the risk of corrosion, while contactless grinding technology would minimise wear contamination.
The researchers, who included Dr Segun Isaac Talabi, Prof. Ismaila Idowu Ahmed, Engr Raheem Abolore Yahya, Engr Yahaya Taiwo, Dr Jeleel Adekunle Adebisi, Prof. Rasheedat Modupe Mahamood, Prof. Jamiu Kolawole Odusote, Dr Mariam Kehinde Sulaiman, Prof. Lawrence Aderemi Olatunji, and Prof. Sulaiman AbdulKareem, said that the persistence of this problem, coupled with the lack of regulation, has meant that Nigerians of all ages have been consuming ground foods without full knowledge of the health implications.
The Principal Investigator also revealed that foodstuff such as maize, pepper, and spices ground with local machines are contaminated by metallic wear particles and corrosion products from deteriorating discs.
“This deterioration takes two main forms: tribological wear, caused by friction between the discs during grinding, and corrosion, triggered by chemical reactions with water and oxygen,” he explained.
“Our research shows clearly that the wear and corrosion of grinding discs are not mere mechanical failures but public health threats.”
Prof. AbdulKareem disclosed that microscopic metallic fragments , including iron, chromium, and manganese oxides were found in the ground food samples.
“For every 10 kg of maize ground, up to 1.7g of metallic magnetic contaminant with an average size of 43 μm was recovered. This is alarming, as repeated ingestion can lead to intestinal lacerations, organ damage, digestive disorders, and even cancer,” he said.
The team emphasised that dry grinding generated more contaminants than wet grinding, but both methods posed significant dangers to consumers. While locally fabricated machines provide affordable access to food processing, the researchers warned that the hidden cost is the gradual poisoning of food.
They, therefore, urged the government to strengthen regulatory tools to enforce stringent quality control measures, ensure safer machine designs, and embark on urgent public education campaigns.
The findings of the research, was published in the Quartile 1 journal Results in Engineering, emerged from a TETFund-sponsored study under the National Research Fund (NRF) Intervention 2020 with reference number TETF/DR&D/CE/NRF2020/SETI/85/VOL.1. The study has so far produced seven publications.
By drawing attention to this overlooked hazard, the UNILORIN researchers highlighted the intersection of engineering and food safety, demonstrating that safe nutrition is not only about what is cultivated in farms but also about the tools used in processing food before it reaches the table.
