Food chemistry: Acrylamide from Maillard reaction products
The discovery of the adventitious formation of the potential cancer-causing agent acrylamide in a variety of foods during cooking has raised much concern, but the chemical mechanism(s) governing its production are unclear. Here we show that acrylamide can be released by the thermal treatment of certain amino acids (asparagine, for example), particularly in combination with reducing sugars, and of early Maillard reaction products (N-glycosides). Our findings indicate that the Maillard-driven generation of flavour and colour in thermally processed foods can — under particular conditions — be linked to the formation of acrylamide.
Analysis of acrylamide in food products by in-line preconcentration capillary zone electrophoresis.
Two in-line preconcentration capillary zone electrophoresis (CZE) methods (field amplified sample injection (FASI) and stacking with sample matrix removal (LVSS)) have been evaluated for the analysis of acrylamide (AA) in foodstuffs. To allow the determination of AA by CZE, it was derivatized using 2-mercaptobenzoic acid. For FASI, the optimum conditions were water at pH > or = 10 adjusted with NH3 as sample solvent, 35 s hydrodynamic injection (0.5 psi) of a water plug, 35 s of electrokinetic injection (-10 kV) of the sample, and 6s hydrodynamic injection (0.5 psi) of another water plug to prevent AA removal by EOF. In stacking with sample matrix removal, the reversal time was found to be around 3.3 min. A 40 mM phosphate buffer (pH 8.5) was used as carrier electrolyte for CZE separation in both cases. For both FASI and LVSS methods, linear calibration curves over the range studied (10-1000 microg L(-1) and 25-1000 microg L(-1), respectively), limit of detection (LOD) on standards (1 microg L(-1) for FASI and 7 microg L(-1) for LVSS), limit of detection on samples (3 ng g(-1) for FASI and 20 ng g(-1) for LVSS) and both run-to-run (up to 14% for concentration and 0.8% for time values) and day-to-day precisions (up to 16% and 5% for concentration and time values, respectively) were established. Due to the lower detection limits obtained with the FASI-CZE this method was applied to the analysis of AA in different foodstuffs such as biscuits, cereals, crisp bread, snacks and coffee, and the results were compared with those obtained by LC-MS/MS.
Study of Biogas for Power Generation at Pesantren Saung Balong Al-Barokah, Majalengka, West Java
Utilization of biogas from cow manure as a fuel alternative for power plants is done through an anaerobic process. A pilot plant with biogas production of 7 m 3 /day has been installed at Pesantren Saung Balong. Biogas is used for everyday purposes such as cooking and lighting, and used as pure biogas with 2.500 Watt scale generator. Biogas produced with the rate of 0.080 m 3 /hr. Biogas produced during the measurement (450 minutes) is 0.604 m 3 . With these data it is predicted that within a day (24 hours) biogas which can be generated is equal to 1.92 m 3 . Meanwhile, consumption of biogas to the generator with 1.047 W load is 0.019 m3/minutes, the generator will operate for approximately 101.05 minutes or 1.68 hours. Thus electricity that can be saved is 1.759 kWh per day or 52.77 kWh per month and electricity cost that can be saved that is equal to Rp.40.896/month.