Identification of volatile organic compounds with reference to water activity in salt cured and sun dried Indian mackerel (Rastrelliger kanagurta) by Headspace Gas Chromatography and Mass Spectrometry (HS-GCMS)

Abstract

The volatile organic compounds (VOCs) released from salt cured and sun dried Indian mackerel (Rastrelliger kanagurta) was studied by headspace gas chromatography and mass spectrometry (HS-GCMS). Volatile profile from the stage of salt curing till sun drying upto 4 days were profiled which revealed diversifications in their production and occurrence. Alcohols viz., 1-Penten 3-ol, 1-Octen 3-ol and 3-Methyl butanol were dominating in the volatile profile from salt curing stage to 2 days of sun drying. Aldehyde hexanal was first detected after first day sun dried samples which peaked in 2nd day dried fish. The presence of various esters were detected in samples dried for two days or more. The moisture content (%) and water activity (aw) of the samples were found to be influential in production and diversity in the profile of VOCs as the percentage of volatiles decreased with the reduction of these parameters. These VOCs detected are reportedly responsible for the odour, aroma and other flavour characteristics of dry fish in general and their mechanism of production is discussed.