The Effect of Roasting on the Protein Profile and Antiradical Capacity of Flaxseed Meal

Abstract

Roasting is more and more often used as a pre-treatment of flaxseeds. However, the process can influence flaxseed proteins that may be crucial for their properties. The aim of this research was to study changes in the electrophoretic protein profile (SDS-PAGE) and the antiradical capacity of flaxseed meals after roasting. The roasting temperature (160, 180, and 200 °C) and flaxseed cultivars (golden and brown seed) were factors including in the study. The free (F-MRP) and bound-to-protein (B-MRP) Maillard reaction products were also analyzed. The most significant changes in the SDS-PAGE protein profiles of roasted seeds of each of the tested flax cultivars were observed for the 13 kDa protein fraction (decrease) and for the 19 kDa and 17 kDa fractions (increase). The research revealed a significant correlation between the roasting temperature and B-MRP content, and changes in the percentage share of those three protein fractions. The antiradical capacity of roasted flaxseeds decreased, as compared with untreated seeds. After roasting at 200 °C the antiradical capacity of flaxseeds improved slightly, probably due to the MRP formation, but it was still significantly lower than that of the raw seeds. The research provides novel information about key protein fractions that seem to be important changing during heat treatment.

Antiradical Potential of Food Products as a Comprehensive Measure of Their Quality

“…Within the latter group, there is also an increase in potential for lightly-roasted and low-fermented coffee and tea varieties compared to more heavily processed ones [ 42 , 43 ]. Most likely, the effect of temperature reduces the ARP parameters in a similar way for other types of food raw materials [ 44 ]. We analyzed a medium-roasted coffee, which occupies an intermediate position in Table 6 between hibiscus and tea.…”

Protein Fractions from Flaxseed: The Effect of Subsequent Extractions on Composition and Antioxidant Capacity

“…The research materials were the protein fractions of flaxseed ( Linum usitatissimum L.) obtained from of three cultivars: golden-seed Jantarol, Oliwin and brown-seed Szafir (IHAR, Borowo, Poland; year of production: 2017; for the chemical composition of the material see Waszkowiak and Mikołajczak [ 22 ]). The material preparation included grinding in a ZM 200 mill (1 mm sieve, Retsch, Haan, Germany), double cold oil extraction (ground seed to n-hexane ratio of 1:3 w / v ) and then grinding in a colloidal mill (Foss, Hilleroed, Denmark) to standardise the material composition.…”

The Influence of Flaxseed Oil Cake Extract on Oxidative Stability of Microencapsulated Flaxseed Oil in Spray-Dried Powders

“…Secondary oxidation products contribute to a loss in nutritional and organoleptic properties of food [ 9 ]. Lipid oxidation contributes to a reduction in the quality of food rich in fats, which is a serious problem in food storage and distribution [ 12 ]. Moreover, some products of oxidation are toxic and reduce the bioavailability of fatty acids.…”