Concentration and probabilistic health risk assessment of benzo(a)pyrene in extra virgin olive oils supplied in Tehran, Iran.

One hundred and sixteen samples of extra virgin olive oils (VOOs) from markets of Tehran were analyzed by high-performance liquid chromatography (HPLC) to detect the amount of benzo (a)pyrene. The values of LOD and LOQ were calculated as 0.03 and 0.05 µg/kg, respectively. The concentration of benzo (a) pyrene was from 0.03 to 0.95 µg/kg. The results indicate that the levels of benzo (a) pyrene are lower than the limits approved. Target Hazard quotient (THQ) and Margin of Exposure (MOE) were estimated. The mean of THQ for adults and children was 0.0006 and 0.0028 and also mean of MOE for adults and children was 43,503 and 9438, respectively. The probabilistic health risk shows that THQ is less than 1 value; hence consumers are not at non-cancer risk. The mean of MOE value for adults was more than 10,000 but for children was less than 10,000. Hence, children are at health risk borderline.

Formation and reduction of 5-hydroxymethylfurfural at frying temperature in model system as a function of amino acid and sugar composition.

5-Hydroxymethylfurfural (HMF) is formed during heat treatment of carbohydrate-containing foods, especially in a deep-fat frying process. This study aimed to investigate the effect of amino acids on the formation and reduction of HMF from glucose, fructose and sucrose at frying temperature in model systems containing binary mixtures of an amino acid and a sugar in equal concentrations (0.3M). The results revealed that the formation of HMF from sugars accelerated in the presence of acidic amino acids (i.e. glutamic and aspartic acids). Conversely, the presence of basic amino acids (i.e. lysine, arginine and histidine) led to reduced concentrations of HMF to non-detectable levels in model systems. The results showed that both pH and heating time significantly affected the formation of HMF from fructose in the presence of glutamic acid. In this regard, a higher amount of HMF was formed at lower pH.

Validation of a HPLC method for determination of hydroxymethylfurfural in crude palm oil.

For the first time 5-hydroxymethyl-2-furaldehyde (HMF) was separated from crude palm oil (CPO), and its authenticity was determined using an RP-HPLC method. Separation was accomplished with isocratic elution of a mobile phase comprising water and methanol (92:8 v/v) on a Purospher Star RP-18e column (250mm×4.6mm, 5.0µm). The flow rate was adjusted to 1ml/min and detection was performed at 284nm. The method was validated, and results obtained exhibit a good recovery (95.58% to 98.39%). Assessment of precision showed that the relative standard deviations (RSD%) of retention times and peak areas of spiked samples were less than 0.59% and 2.66%, respectively. Further, the limit of detection (LOD) and LOQ were 0.02, 0.05mg/kg, respectively, and the response was linear across the applied ranges. The crude palm oil samples analysed exhibited HMF content less than 2.27mg/kg.