The influence of cooking methods and some marinades on polycyclic aromatic hydrocarbon formation in beef meat

This study aimed to determine the effect of various marinades and their concentrations, as well as various cooking procedures, on polycyclic aromatic hydrocarbon (PAH) formation in cooked beef. The PAH levels in meat were determined, based on the saponification of lipids by methanolic/potassium hydroxide solution, followed by liquid–liquid extraction and QuEChERS method. Pan frying caused lower levels of BaP (1.39 versus 1.62 µg/kg) and PAH4 (5.58 versus 5.73 µg/kg) in beef meat than barbecuing. For sage and thyme extracts prepared at 0.5 to 2.0 °Brix, a significant decrease in the PAH levels of barbecued meat samples was achieved compared to the controls. The levels of PAHs in the samples containing the commercial marinating material were found to be higher than those in the non-marinated control. The BaP and PAH4 levels found in the meat samples marinated with sage and thyme extracts, were below the EU maximum levels. However, BaP was the highest for Control 2 (2.26 µg/kg), and exceeded the EU maximum limit of 2 mg/kg for BaP in heat-treated meat and meat products. The results show a reducing effect of sage and thyme extracts that are normally used during marinating of meat, on the formation of PAH compounds. Consequently, the extracts of sage and thyme, could be used in the commercial marinating material to reduce the level of PAH compounds formed in meat during cooking

Sorption isotherms of coffee in different stages for producing Turkish coffee

The aim of this research was to determine the adsorption behavior of coffee as green and roasted beans and ground. For this aim, the static gravimetric method was used and samples were kept in the different water activity levels between 0.01 and 0.91 at 25°C for 7 days. The data were evaluated using the BET (Brunauer-Emmett-Teller), GAB (Guggenheim, Anderson and deBoer), Halsey, and Peleg sorption equations. The constants m0 and C of BET and GAB equations were determined to be between 2.13 and 6.61 g water/100 g of dry matter and 30.05–429.60, respectively. The isotherms of all coffee samples were defined as Type II because the C constant of the GAB equation was higher than 2. Additionally; the BET, GAB, and Peleg equations were determined to fit better than the Halsey for adsorption properties of coffee because E% values were lower than 10% and the coefficient of regression values approached the 1.00