Propanethial S-Oxide Content in Scallions (Allium fistulosum L. Variety Caespitosum) as a Possible Marker for Freshness during Cold Storage

Abstract

Propanethial S-oxide (PSO), known as a precursor of flavor chemicals in Allium species, was analyzed in scallions (Allium fistulosum L. var. Caespitosum) stored at 0 and 5 o C for 1-5 weeks. The levels of PSO from scallions stored at 5 o C were much higher than those from scallions stored at 0 o C. PSO comprised 80-90% of the total volatiles of all the samples obtained from scallions. The amounts of total volatiles and PSO from scallions stored at 5 o C increased for the first week and then decreased slightly