Nut Allergenicity: Effect of Food Processing

Abstract

Nuts are considered healthy foods due to their high content of nutritional compounds with functional properties. However, the list of the most allergenic foods includes tree nuts, and their presence must be indicated on food labels. Most nut allergens are seed storage proteins, pathogenesis-related (PR) proteins, profilins and lipid transfer proteins (LTP). Nut allergenic proteins are characterized by their resistance to denaturation and proteolysis. Food processing has been proposed as the method of choice to alter the allergenicity of foods to ensure their safety and improve their organoleptic properties. The effect of processing on allergenicity is variable by abolishing existing epitopes or generating neoallergens. The alterations depend on the intrinsic characteristics of the protein and the type and duration of treatment. Many studies have evaluated the molecular changes induced by processes such as thermal, pressure or enzymatic treatments. As some processing treatments have been shown to decrease the allergenicity of certain foods, food processing may play an important role in developing hypoallergenic foods and using them for food tolerance induction. This work provides an updated overview of the applications and influence of several processing techniques (thermal, pressure and enzymatic digestion) on nut allergenicity for nuts, namely, hazelnuts, cashews, pistachios, almonds and walnuts.

Heat Treatment Effects on Food Allergens and Laboratory Test Sensitivity

“…Verhoeckx et al (2015) reported decreased hazelnut allergenicity after roasting [2]. Other studies on the effect of heat on almond demonstrated that its allergenic potential is reduced after thermal treatment [8,17].…”

“…To improve their microbiological, organoleptic, and nutritional properties, they are heated during food processing by cooking, roasting, and baking, for example. Prolonged heating processes can alter food protein structure and chemistry, however, resulting in denaturation, unfolding, hydrolysis of peptide bonds, and aggregation by non-covalent and disulfide bonds [8][9][10]. A consequence of heat-induced change in protein structure is increased allergen potency [7,9,11,12], which can also alter the effectiveness of allergen detection testing [13].…”

Changes in nutritional, health benefits, and pharmaceutical potential of raw and roasted tropical almond (Terminalia catappa Linn.) nuts from Nigeria

“…More so, the consumption of nuts would suppress hunger by modulating either the postprandial appetite or desire to eat, which creates a feeling of satiety [ 6 ]. More so, the processing methods applied to nuts generally enhances their organoleptic quality with long-term preservation [ 7 ]. From thermal (such as heating, blanching, roasting and frying) [ 8 ] to non-thermal (such as high hydrostatic pressure treatment and enzymatic treatment) types, the processing methods of nuts capably modify various characteristic qualities within the component matrix [ 7 ].…”

“…More so, the processing methods applied to nuts generally enhances their organoleptic quality with long-term preservation [ 7 ]. From thermal (such as heating, blanching, roasting and frying) [ 8 ] to non-thermal (such as high hydrostatic pressure treatment and enzymatic treatment) types, the processing methods of nuts capably modify various characteristic qualities within the component matrix [ 7 ]. Given the aroma, flavor, texture, and color improvements that results, the roasting process continues to thrive as the increasingly preferred processing method for nuts [ 9 ].…”

Non-thermal processing of cashews: irradiation reduces allergenicity by altering the structure of Ana o 3

“…A variety of food processing techniques, including traditional thermal technologies and emerging non-thermal techniques, were used to reduce food allergenicity. 11,12 Traditionally, thermal technologies such as boiling and roasting could reduce the allergenicity of some foods to some extent, and this would negatively affect nutrient compositions and result in uncontrollable by-products. 13 However, non-thermal processing could improve nutrition properties and reduce food immunoreactivity.…”