Immunoreactivity of Lupine and Soybean Allergens in Foods as Affected by Thermal Processing

Abstract

Lupine and soybean are important technological aids for the food industry. However, they are also capable of inducing severe allergic reactions in food-sensitized/allergic individuals. In this context, this work intended to study the combined effects of thermal processing and food matrix on the immunoreactivity of lupine and soybean proteins used as ingredients in bakery and meat products, respectively. For this purpose, the effects of baking, mild oven cooking, and autoclaving on the protein profiles were evaluated, using model mixtures simulating the production of lupine-containing breads and soybean-containing cooked hams/sausages, by native- and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and immunoblotting using specific antibodies. The results showed that lupine gamma-conglutin immunoreactivity was slightly decreased in wheat flour mixtures compared to rice, but it was more pronounced in baked products. In meat mixtures, substantial protein fragmentation was noted after autoclaving, with decreased immunoreactivity of soybean trypsin inhibitor. The analysis of 22 commercial products enabled the identification of lupine gamma-conglutin in four bakery samples and soybean trypsin-inhibitor in five sausages, and further differentiated autoclaved from other milder thermally treated products. Generally, the immunoreactivity of target proteins was reduced by all the tested thermal treatments, though at a higher extent after autoclaving, being slightly altered by the food matrix.

Lupine allergens: Clinical relevance, molecular characterization, cross‐reactivity, and detection strategies

“…Additionally, the induction of an IgE response depends on their intrinsic properties, as well as the matrix in which the proteins are administered (Foss et al, 2006;Holden et al, 2008). More recently, Villa, Moura, Costa, and Mafra (2020) reported a higher reduction in the immunoreactivity of γ-conglutin in model breads containing lupine than in raw mixtures (model flour mixtures of rice or wheat with lupine), which agrees with previous findings (Alvarez-Alvarez et al, 2005;Holden et al, 2008;Rojas-Hijazo et al, 2006).…”

Modification of In Vitro and In Vivo Antioxidant Activity by Consumption of Cooked Chickpea in a Colon Cancer Model

“…Another report indicated that in these macro compounds, the main changes were not in the concentrations but in the digestibility and bioavailability of nutrients [54]. Villa et al [55] reported that after heat treatments, allergenicity is decreased, and proteins were denatured, leaving the peptide bonds and the digestive enzyme recognition sites more exposed, making it easier to break the bonds. Additionally, there was also a certain degree of hydrolysis favored by heat, which could increase the antioxidant activity of proteins due to the increased exposure of R groups and the release of peptides with antioxidant activity [55,56].…”

“…Villa et al [55] reported that after heat treatments, allergenicity is decreased, and proteins were denatured, leaving the peptide bonds and the digestive enzyme recognition sites more exposed, making it easier to break the bonds. Additionally, there was also a certain degree of hydrolysis favored by heat, which could increase the antioxidant activity of proteins due to the increased exposure of R groups and the release of peptides with antioxidant activity [55,56]. A similar effect was seen in carbohydrates; Chinedum et al [57] reported that in cooked beans, there was no significant loss in quantity, although the most soluble ones such as α-galactosides decreased.…”

High Hydrostatic Pressure-Assisted Enzymatic Hydrolysis Affect Mealworm Allergenic Proteins

“…Different food processing methods, such as boiling [9,10], autoclaving [11], extrusion [12], microwave [13], pulsed-electric field [14], ultrasound [15], and HHP [16,17], may alter the intrinsic structure of food proteins and, consequently, decrease their allergenic properties. These processes may be coupled to enzymatic hydrolysis to further decrease the allergenicity of a wide range of conventional food proteins and generate protein hydrolysates that could potentially be integrated into specific formulations for food-allergic patients [18].…”