The influences of street food vendor frying equipment on the quality of frying oil

Dagmawit Fekadu; Solomon Abera; Helen Weldemichael

doi:10.1016/j.heliyon.2024.e28293

The influences of street food vendor frying equipment on the quality of frying oil

Heliyon. 2024 Mar 18;10(7):e28293. doi: 10.1016/j.heliyon.2024.e28293. eCollection 2024 Apr 15.

Authors

Dagmawit Fekadu¹, Solomon Abera¹, Helen Weldemichael²

Affiliations

¹ Department of Food Technology and Process Engineering, Institute of Technology, Haramaya University, Dire Dawa, Ethiopia.
² Department of Food Process Engineering, Wolkite University, Wolkite, Ethiopia.

Abstract

This study was initiated to determine the quality of fresh and used oil for street vendor fried food products in Harar City, Ethiopia. Using a purposive sample technique, 12 respondents were selected for the study. The study obtained a total of 12 oil samples, categorized as fresh, in-use, and discarded, from two distinct groups of respondents. Specifically, six samples were collected from vendors utilizing an electric fryer constructed from stainless steel, while the remaining six samples were acquired from vendors employing a pan heated by wood or charcoal.The moisture content of fresh, in-use, and discarded oil samples, among other physical characteristics of the samples obtained from two types of vendors, was examined and found to vary between 0.14 and 0.44%, 0.19 and 0.52%, and 0.25 and 0.75%, respectively. Comparably, the refractive indices of oil samples that were fresh, in use, and discarded were 1.4595-1.4686, 1.4670-1.4885, and 1.4810-1.4960, in that order. Furthermore, the ranges of viscosities for fresh oil, oil samples in use, and oil samples that were discarded were 57.15-76.94, 100-196.50, and 210.22-288.50 mPa, respectively. Chemical properties, including % free fatty acid for similar samples, range from 0.22 to 1.30, 1.12 2.54, and 1.38-3.66%, respectively. Peroxide values of fresh, in-use, and discarded oil samples, have a maximum value of 11.19 meq/kg, 42.90, and 57.60 meq/kg, respectively. The iodine value showed the highest value for the fresh oil sample, while the minimum was obtained under discarded oil sample. The result indicated that they used low-quality oil. The values obtained after frying for samples collected from vendors who used a pan fryer heated with charcoal or wood fire deviated significantly from the requirements, indicating that the palm oil used by those street vendors was unsafe to consume because it could endanger the consumers' health.

Keywords: Chemical properties; Discarded; Fresh; In use; Oil samples.