General composition, minerals and free amino acids in “Azaki daikon” traditional vegetable of Aizu

Abstract

 Recently, based on the decreasing food safety and security, along with a reduction in the food self-sufficiency ratio, concepts such as local production for local consumption and slow foods have focused attention on traditional vegetables locally grown all across Japan. In this study, the general composition, minerals, free amino acid composition, and other characteristics of Azaki daikon and Akasuji daikon, the traditional Aizu vegetables, were clarified by making comparisons with Aokubi daikons.
  Compared to the Aokubi and Akasuji daikons, Azaki daikon had a lower moisture content, and higher levels of proteins, lipids, ash, potassium, zinc, iron, and other nutrients. The total amount of free amino acids was greater in the Azaki daikon than in the Aokubi and Akasuji daikons. While the main free amino acids in the Aokubi and Akasuji daikons were glutamine and γ-aminobutyric acid, those in the Azaki daikon were glutamine, arginine, and γ-aminobutyric acid, with a significantly high level of arginine.
  The results of this study suggest that Azaki daikon, which contains particularly high levels of total free amino acids, glutamine, arginine, and γ-aminobutyric acid, may be an important food item with utility for flavor and added health benefits.