Effect of salts on the formation of acrylamide, 5-hydroxymethylfurfural and flavour compounds in a crust-like glucose/wheat flour dough system during heating.

Among many strategies known to mitigate acrylamide formation, addition of cations, particularly calcium, is effective and can be used in bakery products. In this study, the effects of NaCl, KCl, CaCl2, MgCl2, sodium lactate, calcium lactate, and magnesium lactate on aroma and acrylamide formation were investigated in glucose/wheat flour dough systems during heating. Addition of salts inhibited Maillard reaction in favour of caramelisation, with divalent cations found to be most effective. The impact of salts on acrylamide reduction became less effective with increasing temperature. Most Strecker aldehydes and pyrazines decreased in the presence of salts, however CaCl2 and calcium lactate increased the concentration of furans, furfurals, and diketones. Calcium lactate also increased some ethyl-substituted pyrazines at high temperatures. Reduction of acrylamide with salts is associated with higher amounts of furan derivatives and decreased amounts of Strecker aldehydes and pyrazines. The mechanisms behind these changes are discussed.

Effectiveness of asparaginase on reducing acrylamide formation in bakery products according to their dough type and properties.

Effect of asparaginase was tested in different biscuit and cracker doughs, and wafer batter by changing processing conditions such as enzyme dosage, dough resting time and temperature, mixing speed and time, and mixing procedure of the recipe components. Acrylamide reductions achieved were 96, 80, 54% in rotary cut biscuits, crackers and wire cut cookies, respectively due to high water activity of their dough. Asparaginase did not affect surface color or spread ratio. There was a positive correlation between asparagine content and acrylamide formation except for rotary molded biscuit doughs. No significant decrease was found in rotary molded biscuits because of low water (water activity of 0.70) and high fat content. This indicated that water activity of dough is an important factor for the effectiveness of asparaginase treatment. The results suggested that water activity value exceeding 0.75 is needed in the dough to effectively reduce asparagine, so acrylamide in bakery products.

Maillard reaction and caramelization during hazelnut roasting: A multiresponse kinetic study.

A comprehensive kinetic model indicating the elementary steps of Maillard reaction and caramelization during hazelnut roasting was proposed based on a multi-response kinetic modeling approach. Changes in the concentrations of sucrose, fructose, glucose, amino acids, 3-deoxyglucosone, 1-deoxyglucosone, 3,4-dideoxyglucosone, glyoxal, methylglyoxal, dimethylglyoxal, and 5-hydroxymethylfurfural were examined in hazelnuts during roasting at 150, 160 and 170°C for 15, 30, 60, 90, and 120min. The results suggested that 1,2-enolization was important in the interconversion of glucose and fructose, 5-hydroxymethylfurfural formation mainly proceeded via fructofuranosyl cation dehydration rather than 3-deoxglucosone, glucose contributed more than fructose and fructofuranosyl cation to the early stage of the Maillard reaction. Methylglyoxal and dimethylglyoxal were mainly formed from 1-deoxyglucosone with high reaction rate constants while glyoxal formed through glucose degradation. α-Dicarbonyl compounds could have a role in the formation of melanoidins. The temperature dependence of the reactions was complicated and could not be explained by the Arrhenius equation.