Quantitative gas chromatographic analysis of the volatile aroma components has been used as an objective measure of the effects of maturity at harvest, ripeness and storage on the aroma volatiles of kiwifruit. Increasing ripeness is associated with a rapid increase in the levels of aroma volatiles, especially esters, while increasing storage time prior to ripening is accompanied by a decrease in the amount of aroma volatiles.

Volatile aroma constituents of pepino Puit (Solanum muricatum) were separated by simultaneous distillation and extraction (SDE). They were analysed by gas chromatography and mass spectrometry. Major components in the volatiles were 3-methyl-2-buten-1 -01,3-methyl-3-buten-l-01, 3-butenoate have been identiJied as minor components. The last three compounds were previously unknown as natural products.Aroma constituents J;om three cultivars, El Camino, Kawi and Suma, were compared with one another.

A BSTRA C T The relative roles of volatile and non-volatile compounds and fruit firmness in the sensory attributes of ripe kiwifruit (Actinidia deliciosa(

The volatile constituents of kiwifruit (Actinidia chinensis Planch.) have been investigated. The volatiles were collected and concentrated using vacuum steam distillation and freeze concentration. The concentrated distillate was analysed by gas chromatography, gas chromatography-mass spectrometry and reaction gas chromatography. Apart from methyl benzoate, all the components identified were alkyl and alkenyl esters, alcohols, aldehydes and ketones. The most abundant component was trans hex-2-enal. Odour evaluation of the components at the exit port of the gas chromatograph indicated that ethyl butanoate, hexanal and trans hex-2-enal are important contributors to the aroma of kiwifruit. One other component which does not show a peak in the chromatogram and which is not yet completely characterised may have particular significance.

Glycosidically bound volatiles in kiwifruit have been studied. The compounds were isolated from kiwifruit juice by absorption onto a column of Amberlite XAD-2 followed by washing with pentane and elution with methanol. Volatiles were released by enzymic hydrolysis with 8-glucosidase. Major components found and identified by GC-MS were E-hex-2-enal and benzaldehyde.Compounds not previously identified in kiwifruit include octan-3-01, camphor, 4-methylbenzaldehyde, 2-hydroxybenzaldehyde, neral, geranial, methyl 2-hydroxybenzoate, nerol, geraniol and 2-phenylethanol.