Soybean Allergens: Presence, Detection and Methods for Mitigation

Abstract

As a major food ingredient, soybean provides numerous health benefits, for example, individuals who consume soybean-rich diets exhibit lower incidence of high plasma cholesterol, cancer (including bowel and kidney), diabetes mellitus, and obesity (Carroll and Kurowska, 1995; Friedman and Brandon, 2001; Duranti et al., 2004; Ali et al., 2004; Omini and Aluko, 2005; Kim et al., 2006). However, soybean is also among the “big 8” most allergenic foods, and the only possible solution currently to prevent allergenic reactions is total avoidance of the allergen-containing foods. Because soybean is ubiquitous in vegetarian and many meat based food products, avoidance has become increasingly difficult, and its prevalence will inevitably continue to rise. Due to the innumerable health benefits and economic importance of soy commercial products, there is a mounting need to remove the allergenic components contained in soybean proteins to a threshold deemed to be safe. The estimated threshold level for common food allergy is usually low and a small amount of the allergen may be enough to trigger an allergenic reaction (Poms et al., 2004). The threshold for soybean allergen is estimated to range from 88 mg to several grams of soy protein (Bindslev-Jensen et al., 2002; Fiocchi et al., 2003). Soybean allergy is of particular importance because soybean is widely used in processed foods and represents a particularly insidious source of hidden allergens. Since finding foods that do not contain soy is difficult and total elimination of food allergens is practically impossible to attain, investigations on the hypoallergenization of soy ingredients and products are imperative. Current requirements by the labeling regulations also make it imperative to identify a processing technology that is capable of reducing or eliminating the allergens from soy containing products. Elimination or reduction of allergens in allergenic foods has been attempted for years by various investigators, which has included, among various strategies, the use of genetic engineering, thermal processing, enzyme treatment, ultrafiltration, chemical agents, microwave, irradiation, high pressure processing, pulsed ultraviolet light, power ultrasound and pulsed electric field. The reduction or elimination of allergens from soybean proteins by different processing technologies offers unique insight to the structure and biological interaction of the antigenic proteins. With allergens reduced, the industry can further profit from the economical attributes of soybean and promote the