ABSTRACT
Heated plant foods may contain compounds with adverse health effects (e.g. acrylamide). On the other hand, health-promoting compounds (e.g. antioxidants) have also been identified in such foods. Therefore, a baking experiment with biscuits was carried out to study the potential impact of both acrylamide and antioxidants in that food. Two different wheat flour types - wholemeal (WMF) and white flour type 550 (T550; 0.55% mineral content) - as well as recipe (fat and leavening agent) and thermal input (temperature × time) were changed. Furthermore, the effect of an enzymatic asparagine hydrolysation was tested. Antioxidants were determined with two independent procedures ABTS - (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate)) and FRAP-assay (ferric reducing ability of plasma). WMF samples resulted in an unchanged acrylamide level, but in a significantly higher antioxidant concentration when compared with T550 samples (149 and 141 µg kg(-1) acrylamide and 9.1 and 5.1 mmol TE kg(-1) FW ABTS for WMF and T550, respectively). A reduced fat content yielded in an increased volume. Raising agents had no effect on acrylamide levels, but antioxidants were higher in samples with sodium bicarbonate (SBC) than with ammonium bicarbonate (ABC). Thermal input (temperature × time; 150°C × 25 min to 240°C × 9 min) indicated an exponential acrylamide increase especially at higher temperatures (from 75 to 236 µg kg(-1)), whereas antioxidant increase was linear (from 7.0 to 7.7 mmol TE kg(-1) FW, ABTS). FRAP and ABTS values were correlated on a low level, whereas acrylamide content of biscuits was correlated with FRAP and lightness (R (2 )= 0.62 and 0.47, and 0.71 and 0.85 for WMF and T550, respectively). The enzyme asparaginase reduced acrylamide formation by about 50% for both raising agents (SBC and ABC, respectively), whereas antioxidant levels were not affected. An evaluation of recipe variants with low acrylamide and high antioxidants indicated the advantage of wholemeal biscuits.
Subject(s)
Acrylamide/analysis , Antioxidants/analysis , Bread/analysis , Carcinogens/analysis , Food Contamination , Food Handling , Acrylamide/chemistry , Bicarbonates/chemistry , Carcinogens/chemistry , Color , Dietary Fats/analysis , Dietary Fiber/analysis , Flour/analysis , Food Contamination/prevention & control , Germany , Hot Temperature/adverse effects , Hydrolysis , Sodium Bicarbonate/chemistry , Time FactorsABSTRACT
Ten Croatian and five German wheat varieties were tested. They were carried out using the German standard testing protocol. The results demonstrated that the quality of the Croatian wheat varieties could be ranged in A-C quality groups according to the German testing protocol. Croatian wheat varieties were comparable in many parameters (protein content, hardness, water absorption, dough handling properties and volume yield) with chosen German wheat varieties. Some differences were found in falling number, sedimentation value, flour yield, and ash value number.
Subject(s)
Plant Proteins/analysis , Triticum , Chemical Phenomena , Chemistry, Physical , Croatia , Food Technology , Germany , Nutritive Value , Quality Control , Triticum/chemistry , Triticum/classificationABSTRACT
Ten Croatian and five German wheat varieties were tested. Wheat protein composition was analysed according to a modified Osborne fractionation. They were extracted in four fractions: NaCl fraction, ethanol fraction, acetic acid fraction and insoluble fraction. The influence of protein and protein composition on the loaf volume was investigated. In protein composition a difference between the Croatian and German wheat varieties were found. Protein content, glutenin content and insoluble glutenin content showed influences on the loaf volume.
