Changes in the physical-chemical properties and water status of durum-wheat constituents in pasta during processing and cooking.
Pasta is made from simple durum wheat semolina and water, through a succession of unitary operations. Knowledge of the changes of the interactions between these constituents during the various processing and cooking steps is crucial for optimizing the quality of the product. Therefore, the objective of a recent study, carried out by a French team of researchers (Laurent et al, 2023), was to describe these interactions between durum wheat semolina, dry and cooked pasta using complementary analytical methods at different observation scales.
In particular, the samples were investigated by measurements of gelatinization endotherms by DSC (Differential Scanning Calorimetry), viscosity curves of a suspension by RVA (Rapid Viscosity Analyser), proton mobility by NMR (Nuclear Magnetic Resonance Spectroscopy), and molecular interactions by ATR-FTIR spectroscopy (Fourier-Transform Infrared Spectroscopy).
The results clearly demonstrate that the extrusion, drying and firing stages of the product induce specific changes in the protein network and starch granules, driven by mechanical and hydrothermal stresses, and physico-chemical and enzymatic reactions. In summary, the proposed approach can be usefully implemented by the sector’s industry to identify the critical unit operations of the pasta processing process, to maximize the quality of the product.
Influence of drying conditions on the mitigation of Maillard reaction in spaghetti from durum wheat.
The pasta drying process is responsible for heat damages that influence the nutritional value (available lysine) and the color of pasta. These events are triggered by a series of chemical reactions known as the Maillard reaction or non-enzymatic browning. Therefore, the aim of a recent study, carried out by a group of Italian researchers (Cuomo et al., 2023), was to investigate the influence of different operating conditions during the high-temperature drying process on the quality of the pasta, using as a sample wheat flour-based spaghetti.
Different high temperature drying diagrams were set up to modulate time, temperature and duration of pasta exposure to the high temperatures. To find the best compromise between high temperature treatment and mitigation of heat damage, different process markers of the early (furosine, lysine and maltulose) and advanced phase (hydroxymethylfurfural and glucosyl isomaltol) of the Maillard reaction were considered.
The results showed that applying high temperatures in the early stages of the cycle, when the moisture content and water activity of the product are high, can significantly mitigate the effects of the Maillard reaction. In fact, by applying a cycle in which, in the first phase, the maximum temperature of 81°C is reached quickly (in 25 min) and is held for 2.5 h, spaghetti with a reduced value of furosine was produced (200 mg/100 g of protein, i.e. less than 50% of the furosine in conventional pasta), maintaining an optimal cooking quality.
References: Laurent et al., Journal of Cereal Science, 112, 2023, 103737; Cuomo et al., LWT – Food Science and Technology, 184, 2023, 114990.
