The effect of storage on apple juice concentrate was determined by following changes in composition during a period of 111 days at 37°C. Results showed that storage caused an 87% loss in the total free amino acids, which was mostly due to decreases in glutamic acid, asparagine and aspartic acid. The form01 titration method was inadequate for determining the amino compounds involved in Maillard-type reactions. Sucrose was hydrolyzed under these conditions at a rate corresponding to a fist order process. The reducing sugars increased at a rate determined by the inversion of sucrose; no consumption attributable to browning reaction was detected. Reduction of organic acids was 9% while apparent phenolic compounds increased from 0.149 to 0.215 g/lOOg. A maximum accumulation of HMF was observed after 100 days of storage.

Apple juice concentrate manufactured in Argentina was sampled before and after shipment to the USA and subjected to a number of color and compositional analyses. These included browning, haze, Hunter parameters, titratable acidi9, hydroxymethyljurjiural (HMF), and HPLC determination of sugars, nonvolatile acids, and chlorogenic acid. The primary objective was to determine those parameters which showed sign$cant changes as a result of commercial transport. Browning signijicantly increased as did HMF and fumaric acid content. There was no evidence for sucrose inversion and there was no signijicant change in titratable acidity as a result of this 55 day commercial shipment.

A rapid method is described for the quantitative determination of patulin in apple juice. The mycotoxin is extracted from the sample with ethyl acetate and the extract is cleaned up by extraction with a sodium carbonate solution. Patulin is determined by reverse phase liquid chromatography using a μ.Bondapak C18covery is >75%.