Determination of hydroxymethylfurfural and malondialdehyde amounts in various instant coffees commonly sold in Türkiye

Abstract

Coffee is currently one of the most consumed non-alcoholic beverages around the world. Although many beneficial compounds are present in the composition of coffee, it should be taken into account that coffee products may contain some toxic substances. The aim of this study is to determine both 5-hydroxymethylfurfural (HMF) and malondialdehyde (MDA) levels of the most well-known coffee brands in Türkiye and to discuss the factors associated with the increase of these toxic compounds in coffee products. In this research, 30 instant coffee samples were obtained from common commercial markets in Istanbul, Türkiye. The amounts of HMF and MDA in these coffees were determined by high-performance liquid chromatography (HPLC). The amounts of HMF and MDA in the coffee samples ranged from 2.8 to 1595 mg/kg and from 17.5 μg to 212 μg/100 g, respectively. There was no significant relationship between the declared amount of added sugar and the analyzed amount of HMF. The amounts of both HMF and MDA, or either HMF or MDA were generally higher in coffee products with high non-dairy coffee creamer content (82–85 %). The present study provides remarkable findings about the quality of coffee products commonly sold in Türkiye.