ascorbic-acid and isoamyl-acetate

High-molecular-weight (HMW) water-soluble melanoidins were prepared from model systems of L-(+)-ascorbic acid-glycine, L-(+)-ascorbic acid-lysine, L-(+)-ascorbic acid-glutamic acid, and glucose-glycine using a very recently approved standard protocol. The amount of HMW water-soluble melanoidins prepared from L-(+)-ascorbic acid was over 5-15 times higher than the amount obtained from glucose. The study of the release of a model flavor compound, namely isoamyl acetate, from melanoidins by solid-phase microextraction (SPME) showed that SPME is a suitable technique for the analysis of flavor release from melanoidin-containing solutions. From the studies on the retention capacity of the melanoidins toward isoamyl acetate, an increased release of the flavor compound was observed from the melanoidins prepared from the L-(+)-ascorbic acid-glycine model system, whereas the opposite effect was observed from the melanoidins prepared from the L-(+)-ascorbic acid-lysine/glutamic acid model systems. The melanoidins prepared from the glucose-glycine model system had the same effect as the melanoidins prepared from the L-(+)-ascorbic acid-glycine model system.

Topics: Amino Acids; Ascorbic Acid; Dialysis; Glucose; Glutamic Acid; Glycine; Lysine; Molecular Weight; Pentanols; Polymers; Solubility