Allergenicity, trypsin inhibitor activity and nutritive quality of enzymatically modified soy proteins.
Two ultrafiltered soy flour protein fractions were evaluated; the first was obtained by hydrolysis (0.5-3 kDa, F(0.5-3)), and the second was an enzymatically methionine-enriched fraction (1-10 kDa, F(1-10)E). Amino acid profiles, protein quality, allergenicity (against soy-sensitive infant sera) and trypsin inhibitor activity were determined. Fraction F(1-10)E fulfilled amino acid requirements for infants, whereas the F(0.5-3) fraction was methionine deficient. Both fractions were similar in net protein utilization, and F(1-10)E digestibility was comparable with casein and higher (P?<?0.05) than F(0.5-3) or soy isolate. Allergenicity of SF was reduced to 21.5% with the hydrolysis in F(1-10)E and it was not detected in F(0.5-3.) Residual trypsin inhibitor activity with respect to soy flour was 8.1%, 3.3% and 1% for hydrolysate, F(1-10)E and F(0.5-3), respectively. Both fractions presented high nutritive quality and reduced or null allergenicity. The trypsin inhibitor activity decreased along processing and could be a useful indicator for production of hypoallergenic proteins.
De La Barca
Ana María Calderón
AM
Departamento de Nutrición Humana, Centro de Investigación en Alimentación y Desarrollo, Hermosillo, Sonora, México. amc@cascabel.ciad.mx
Wall
Abraham
A
López-Díaz
José Alberto
JA
D000485:Allergens / Q000276:immunology; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D005512:Food Hypersensitivity / Q000276:immunology / Q000378:metabolism*; D005527:Food, Fortified; D006801:Humans; D006868:Hydrolysis; D007223:Infant; D008715:Methionine; D008894:Milk Proteins / Q000276:immunology / Q000378:metabolism; D009753:Nutritive Value; D014674:Plant Proteins, Dietary / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D030262:Soybean Proteins / Q000276:immunology / Q000378:metabolism*; D014361:Trypsin Inhibitors / Q000378:metabolism*
D000485:Allergens; D000596:Amino Acids; D008894:Milk Proteins; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D014361:Trypsin Inhibitors; D008715:Methionine