DETECTION AND PARTIAL CHARACTERIZATION OF 8 BETA-DAMASCENONE PRECURSORS IN APPLES (MALUS-DOMESTICA BORKH, CV EMPIRE)

beta-Damascenone, a potent aroma compound in a variety of natural prod ucts, is primarily liberated from precursors. Isolation of beta-damasc enone precursors from apples Malus domestica Borkh. cv. Empire, using Amberlite XAD-2 adsorption and C-18 flash chromatography columns follo wed by C-18 HPLC, yielded at least eight separate precursors, of which the most abundant was further purified and characterized. Mass spectr a from ion spray tandem MS, GC/MS of TMS sugars, and GC/MS of the enzy matically released aglycon indicated a structure of 9(or pha-L-arabino furanosyl-(1,6)beta-D-glucopyranoside of the acetylenic diol. The size s of the other precursors were estimated from their retention during s ize exclusion chromatography (GPC). The presence of two triglycosides, four or more diglycosides, and two or more free aglycons was consiste nt with the GPC data.