Study of some quality parameters of palm oils sold in Bujumbura markets in Burundi

Abstract

People in and around Bujumbura city of Burundi use palm oil extensively, generally in both crude and refined forms. However, these oils sold in the markets are exposed to various factors affecting quality which include sunlight, unhygienic containers, and heat. This study aimed to assess some quality parameters of crude and refined palm oils sold in five markets in Bujumbura and to determine whether these parameters meet the standards. Furthermore, the crude and refined oils sold were compared in terms of these parameters, and a sample distribution was performed using Principal Component Analysis (PCA). After sampling, physical, chemical and spectroscopic methods were used to determine physicochemical parameters and total carotenoids. The average results for refined and crude palm oils, respectively were: relative density (RD) 0.892±0.001; 0.887±0.001, refractive index (RI) 1.463±0.001; 1.462±0.001, moisture and matter volatile (MVH) 0.974±0.527 % (m/m); 2.429±2.196% (m/m), impurity levels (TII) 4.642±1.228% (m/m); 9.468±1.703% (m/m), the acid value (AV) 4.581±0.591 mg KOH/g; 37.190±1.789 mg KOH/g, the free fatty acid contents (FFA) 2.165±0.757%; 18.671±4.947%, the iodine value (IV) 50.252±7.179 g I₂/100 g ; 54.3±10. 531 g I₂/100 g, the peroxide value (PV) 5.8±2.263 meq O₂/kg; 5.3±2.970 meq O₂/kg; the saponification value (SV) 200.371±3.834 mg KOH/g; 195.384±4.540 mg KOH/g; and the total carotenoid (TC) 10.574±3.801 ppm; 738.913±81.467 ppm. The results of the physicochemical analyses showed that only four (4) parameters met the Burundian and Codex Alimentarius standards. In addition, the total carotenoids contained in crude palm oils also complied with these standards. However, the high acid value (AV) or free fatty acid contents (FFA) and impurity levels (TII) are among the indicators of low quality of the crude oils. Based on these results, there is a need to further ensure the compliance to standards of the palm oils sold in different markets of the Bujumbura city.