Effect of heat treatment and dough formulation on the formation of Maillard reaction products in fine bakery products - benefits and weak points

Possibly harmful compounds (acrylamide, 5-(hydroxymethyl)-2-furfural - HMF), markers of the Maillard reaction extent (furosine, fluorescence, browning, colour), as well as beneficial radical-scavenging capacity were determined in fried fine bakery products, rosquillas, at different heat treatment and dough formulation. In different simplified recipes, saccharose was substituted by glucose and fructose, and a raising agent was added while different temperature and time regimes were applied. Duration of frying from 4 min to 8 min increased the acrylamide content from (43 ± 8) μg·kg-1 to (159 ± 12) μg·kg-1 at 180 °C, and from (94 ± 3) μg·kg-1 to (366 ± 5) μ·kg-1 at 200 °C. Sodium hydrogen carbonate addition resulted in an only weak (13%) decrease in the acrylamide content, but in a more pronounced (80%) suppression of HMF formation. Substitution of saccharose for the mixture of glucose and fructose caused a decrease in acrylamide contents instead of its expected increase, but HMF formation was strongly supported by the presence of fructose. On the other hand, beneficial properties, such as radical-scavenging capacity, browning, colour, and fluorescence parameters were developing with the advance of Maillard reaction. Colour parameters were in good correlation with radical-scavenging capacities of final products prepared from saccharose (correlation coefficients, 0.779-0.981) as well as with acrylamide contents in samples made under all recipe modifications (correlation coefficients, 0.882-0.979). © 2009 VÚP Food Research Institute.Peer Reviewe

Effect of L-asparaginase on acrylamide mitigation in a fried-dough pastry model

A dough resembling traditional Spanish rosquillas was used as a model to represent classical fried-dough pastry to investigate the effects of asparaginase and heat treatment on amino acid levels and acrylamide mitigation. Wheat-based dough was deep fried at 180 and 2001C for 4, 6, and 8min. Two recipes were formulated by addition of different asparaginase levels (100 and 500 U/kg flour) to the dough. The temperature/time profile of the frying process, moisture, sugars, amino acids, acrylamide, and some indicators of the Maillard reaction (hydroxymethylfurfural, color, free fluorescence compounds, and browning) were determined to investigate the extent of the reaction and the effect on reactants. At the both levels of asparaginase used, 96-97% of the asparagine present was converted to aspartic acid, and consequently the acrylamide level was very efficiently reduced (up to 90%). The asparaginase also affected the content of glutamine and glutamic acid in dough, resulting in a 37% increase in glutamic acid compared with the untreated sample. Concerning color, browning and Maillard reaction parameters, no significant changes between untreated and enzymati- cally treated samples were observed, pointing out the potential industrial and domestic enzyme application. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Peer Reviewe