Effect of heat stabilization of wheat on acrylamide content in biscuits.
Bran, middlings and germ refer to the by-products of the milling of common wheat used for the formulation of recombined whole-wheat flours. Although of interest for their nutritional profile, these fractions are rich in asparagine (ASN), the main precursor of acrylamide (AA), and are also unstable due to their high content of unsaturated fatty acids and enzymes. Therefore, heat treatment is required to increase the shelf-life.
Therefore, the objective of a recent study, carried out by a group of Italian researchers (Guarino et al., 2024), was to examine the effects of radio frequencies (RF) at temperatures of 110 (TCS1) and 125°C (TCS2) on the lipase activity and acrylamide (AA) formation in milling fractions and biscuits made from recombined wholemeal flours. The results show that the germ has the highest ASN content (3424 mg/kg) and that AA levels increase more with TSC2 than with TSC1, with the highest concentration in middlings (418 μg/kg).
Biscuits produced using the latter by-product are also characterized by a higher AA content. In conclusion, the authors highlight an additive effect in AA accumulation when heat-stabilized fractions are used for the production of wholemeal biscuits. The selection of milling fractions and the control of heat treatment conditions are therefore relevant activities to limit the accumulation of this toxin.
Development of bakery products with high nutritional quality and environmental sustainability.
The aim of a recent study, carried out by a group of Italian researchers (Turfani et al., 2024), was to develop bakery products with a folate content close to the recommended value of 60 μg/100g. Therefore, starting from the whole grain, the milling by-product of 12% hulled flour, mixed with Manitoba flour, was used to produce samples of “maritozzo”, a traditional dessert from the Lazio region.
The results show that decortication has a positive effect on the reduction of fructane and asparagine content and, therefore, on the formation of acrylamide in the final product. In addition, with the recovery of milling by-products, flour enriched in folate as well as total phenolic acids are made available. The addition of 30% of the milling by-product in the “maritozzo” formulation resulted in an increase of nearly 50% in folate content, as well as a more than 7-fold increase in total phenolic acid content compared to the control.
However, the samples so enriched do not yet meet the recommended value of 60 μg/100 g of folate, but allow, in any case, to cover 10% of the daily requirement of this vitamin. In conclusion, the results obtained so far are definitely promising in terms of placing commercially and nutritionally distinctive products on the market. Further insights are, however, necessary to evaluate the sensory aspects of these new functional foods.
References: Guarino et al., Acts of the 13th AISTEC CONFERENCE, Turin, 19-21 June 2024, 189-193; Turfani et al., Acts of the 13th AISTEC CONFERENCE, Turin, 19-21June 2024, 179-183.
