Detection of Soy Protein in Soy Lecithin, Margarine and, Occasionally, Soy Oil

Abstract

Samples of soy lecithin, soy oil and margarine were tested for the presence of soy proteins by an inhibition technique using ELISA. All but one of the soy lecithin samples contained soy protein, as did some of the soy oil and margarine samples. The positive margarines contained only about 25% as much soy protein as the soy lecithin preparations. The presence of soy proteins in these soy products might account for hitherto unrecognized exposure to soy proteins in various foods.

Antigenicity of the proteins in soy lecithin and soy oil in soybean allergy

“…All samples of soy lecithin and soy oil tested in this study had a very small quantity of protein. Porras et al [10] have detected soy protein in soy lecithin, margarine and soy oil, by an inhibition technique using ELISA. They found soy protein in six out of seven lecithin samples (1.03-27.2 mg/g) and three out of eight soy oil samples (0.11-3.3 mg/g).…”

“…However, Doke et al [9] have shown that proteins which have interacted with oxidized lipids are allergenic to soybeansensitive patients, and that this effect is caused not only by soy oil, but also by other vegetable oils. On the other hand, the presence of soy proteins in soy lecithin and soy oil has been reported by Porras et al [10], but the involvement of these proteins in soybean allergic diseases has not been established.…”

“…On the other hand, the presence of soy proteins in soy lecithin and soy oil has been reported by Porras et al . [ 10], but the involvement of these proteins in soybean allergic diseases has not been established.…”

Re‐evaluation of lecithins (E 322) as a food additive

“…Many of these methods have not been validated and, in addition, interferences from residual lipids may confound the chemical assay results. Results for protein content are in the range 115–27,000 mg/kg for crude soya lecithins, 232–1338 mg/kg for in fluid soya lecithin, 65–480 mg/kg for in deoiled soya lecithin and 49 mg/kg for in egg lecithins (Document provided to EFSA n.18; Porras et al., ; Müller et al., ; Gu et al., ; Paschke et al., ; Martin‐Hernandez et al., ).…”

Soybean Allergens: Presence, Detection and Methods for Mitigation

“…An antibody was raised against Kunitz-type soybean typsin inhibitor that worked equally well against native and denatured protein (Barkholt et al, 1994). Porras et al (1985) developed an ELISA for the detection of soy protein in soy lecithin, margarine and soy oil, with sensitivity between 100 and 200 mg/kg. Two soy allergens were measured by a sandwich ELISA (Gly m Bd 30K and Gly m Bd 28K, respectively) with monoclonal antibodies for both the immobilized and the capturing antibodies Bando et al, 1998).…”