title: Effects of dehulling and storage conditions on cooking requirements and chemical composition of soybeans.
abstract: Changes in cooking requirements and chemical composition of whole and dehulled soybeans, stored in 2 different environments [25 degrees C /75% R.H. (Environment 1) and 38 degrees C /90% R.H. (Environment 2)], were studied. Rate of water absorption and solid losses during cooking were higher for the dehulled soybeans at both storage conditions. However, cooking requirements to achieve the same degree of texture in the cotyledons were similar for whole and dehulled seeds. Cooking time increased with prolonged storage; the effect was more noticeable in samples stored under Environment 2. Samples kept for 6 months required almost twice as much cooking than control samples. Dehulled soybeans had a lower fiber content, relatively higher amounts of protein and fat, but similar amino acid compositions than whole soybeans. Cooking caused losses of carbohydrates and ash and, therefore, significantly increased levels of protein and fat reflected by losses of solids during soaking and cooking. Among the amino acids, only cysteine suffered substantial decrease as a result of cooking. Cooking and storage inactivated 99% and from 20-35% of the trypsin inhibitors, respectively; the latter effect was more accentuated in samples stored under Environment 2.
authors.affiliation: EMBRAPA-CTAA, Guaratiba, Rio de Janeiro, Brazil.
authors.forename: L C
authors.initials: LC
authors.lastname: Cabral
authors.forename: S O
authors.initials: SO
authors.lastname: Serna-Saldivar
authors.forename: A M
authors.initials: AM
authors.lastname: Tinsley
mesh_terms: D005511:Food Handling; D006358:Hot Temperature; D013025:Glycine max / Q000737:chemistry*; D013997:Time Factors