Changes with cooking in the mineral, nitrate nitrogen and amino acid contents of komatsuna (Brassica campestris L. var. komatsuna Matsum.) grown under different soil conditions

Abstract

Komatsuna was grown in normal soil, soil enriched with chemical fertilizers and soil enriched with organic fertilizers to study the changes with cooking in the mineral, nitrate nitrogen and amino acid contents.
The mineral content was highest in komatsuna grown in organically fertilized soil, followed by that grown in chemically fertilized soil and then in normal soil. Cooking tended to reduce the residual Ca and Fe contents in komatsuna grown in all three types of soil. The reduction by cooking of nitrate nitrogen was less in komatsuna grown in organically fertilized soil than in the other two soil types. Cooking tended to increase the contents of flavorrelated amino acids, especially in komatsuna grown in the organically fertilized soil. The sweetness-related and bitterness-related amino acid contents tended to be decreased by cooking.