Determination of Protein Content and Polycyclic Aromatic Hydrocarbon Concentration in Suya Roasted and Sold at Senior Staff Club, Rivers State University

Abstract

The consumption of suya, a popular grilled meat delicacy in Nigeria, has raised increasing public health concerns due to possible contamination with harmful substances. This study determined the protein content and polycyclic aromatic hydrocarbon (PAH) concentrations in suya (roasted beef) sold at the Rivers State University Senior Staff Club, Port Harcourt. Eight sticks of suya were purchased and categorized into two groups according to the time of purchase. Three samples from each group were used for protein analysis, while one stick from each group was used to determine PAH concentrations. Sample 1 was the suya purchased at 11:00 a.m., while sample 2 was the suya purchased at 1:00 p.m. Protein content and PAH concentrations were determined using the Kjeldahl method and Gas chromatography–mass spectrometry (GC–MS), respectively. Results showed that the percentage protein content of sample 2 (45.06 ± 0.06%) was significantly higher than that of Sample 1 (37.10 ± 0.13%), and both values exceeded the United States Department of Agriculture (USDA) 2023/2024 recommended range of 21–30% for roasted or grilled meat. Analysis of PAHs revealed the presence of 16 compounds with varying concentrations. Chrysene had the highest concentrations of 11.17ppm and 11.10ppm in samples 1 and 2 respectively, whereas naphthalene had the lowest concentration (0.10 ppm) in both samples. Carcinogenic PAHs, including benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene, were detected. Although most PAH concentrations were similar in both samples, slight variations were observed, and all measured values exceeded the European Union maximum allowable limit of 0.002 ppm for PAHs in roasted or grilled meat.These findings indicate that while suya is a rich source of protein, the presence of harmful PAHs may expose frequent consumers to significant health risks.