Concentration and health risk assessment of polycyclic aromatic hydrocarbons in commercial tea and coffee samples marketed in Iran.

The aim of the current study was to evaluate the probabilistic health risk and the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in commercial tea and coffee samples. For determining the mentioned contaminants in sixty-four samples, a reliable and sensitive technique was validated and developed. The technique is established on magnetic solid-phase extraction and gas chromatography-mass spectrometry analysis (MSPE/GC-MS). The maximum mean of Æ©PAHs in coffee samples was 13.75 ± 2.90 µg kg-1, while the minimum mean Æ©PAHs in tea samples was 4.77 ± 1.01 µg kg-1. The mean concentration of benzo(a)pyrene (BaP) in samples ranged from 0.64 to 2.07 µg kg-1 which was lower than that of standard levels (10 µg kg-1) established by the European Union (EU). The Monte Carlo simulation results showed that the actual target hazard quotient (THQ) for the adult and children was equal to 1.63E-04 and 1.67E-04, respectively; hence, non-carcinogenic health risk for consumers is negligible. The result of actual incremental lifetime cancer risk (ILCR) was lower than the limits of safe risk (1E-4), indicating no notable possibility of cancer risk due to the digestion of tea and coffee for children and adults. Therefore, it can be concluded that the amount of contamination of popular commercial coffee and tea available in the Iranian market with PAHs is often similar to that found in other countries and was lower than the standard of EU. Thus, the processing conditions of these products must be controlled to prevent the formation of PAHs due to the suspicion of carcinogenicity and mutation.

Pullulan gum production from low-quality fig syrup using Aureobasidium pullulans.

Pullulan is an important polysaccharide with several potential applications in food science, pharmaceutical and cosmetic industries, but high costs of pullulan production are the main limitation for commercial utilization. Therefore, a cost-effective process for pullulan production was developed using fig syrup as an exclusive nutrient source. In particular, the feasibility of using low quality fig syrup as a supplemental substrate for pullulan gum production by Aureobasidium pullulans was investigated. Fermentation was carried out over a range of fig syrup and sucrose degrees Brix (5-15%). Maximum pullulan gum production was observed after 96h using 12.5% fig syrup, yielding approximately14.06 g/L. This value of pullulan production (14.06 g/L) was higher than the amount of pullulan produced using sucrose as substrate (5.01 g/L). In conclusion, fig syrup was an effective substrate for pullulan production by Aureobasidium pullulans, and, therefore, this byproduct deserves attention for the cost-effective and environmentally friendly pullulan production.