Impact of harvest date on the content of volatile components in garlic

Abstract

The aim of this study was to define optimal harvesting date of garlic cv. 'Istarski crveni' by comparing the amount of volatile compounds as one of quality indicators. In total 17 volatile compounds were determined in tested garlic samples by headspace solid-phase microextraction coupled to gas chromatography with flame ionization and mass spectrometric detection (HS-SPME-GC-FID-MS) regardless of harvesting date. Major volatiles diallyl trisulfide, diallyl sulfide, methyl allyl disulfide and diallyl disulfide representing 98.5 % of all the determined compounds have shown no significant difference between harvest dates. Significantly higher content of the two minor volatiles, allyl mercaptane and thieno[2,3-b]thiophene, was found in the last and second when compared to the first harvest date. Principal components PC1 and PC2 explained 78% of the total variance and pointed to certain relations between harvest dates and volatiles. The technological maturity had probably been reached at the first harvesting date since similar amounts of volatiles were found during the observed period.

Keywords

• agricultural practice
• alliin
• cultivar
• gas chromatography
• organosulfur compounds