Comparison of techniques for the isolation of volatiles from cashew apple juice.
BACKGROUND
The aim of this study was to compare the performance of the following techniques on the isolation of volatiles of importance for the aroma/flavor of fresh cashew apple juice: dynamic headspace analysis using PorapakQ(®) as trap, solvent extraction with and without further concentration of the isolate, and solid-phase microextraction (fiber DVB/CAR/PDMS).


RESULTS
A total of 181 compounds were identified, from which 44 were esters, 20 terpenes, 19 alcohols, 17 hydrocarbons, 15 ketones, 14 aldehydes, among others. Sensory evaluation of the gas chromatography effluents revealed esters (n = 24) and terpenes (n = 10) as the most important aroma compounds.


CONCLUSIONS
The four techniques were efficient in isolating esters, a chemical class of high impact in the cashew aroma/flavor. However, the dynamic headspace methodology produced an isolate in which the analytes were in greater concentration, which facilitates their identification (gas chromatography-mass spectrometry) and sensory evaluation in the chromatographic effluents. Solvent extraction (dichloromethane) without further concentration of the isolate was the most efficient methodology for the isolation of terpenes. Because these two techniques also isolated in greater concentration the volatiles from other chemical classes important to the cashew aroma, such as aldehydes and alcohols, they were considered the most advantageous for the study of cashew aroma/flavor.
Department of Food and Nutrition, University of Campinas (UNICAMP), Rua Monteiro Lobato, 80, CEP 13083-862, Campinas, SP, Brazil.
Karina L
KL
Sampaio
Aline C T
AC
Biasoto
Maria Aparecida A P
MA
Da Silva
D031021:Anacardium / Q000737:chemistry*; D001628:Beverages; D005591:Chemical Fractionation / Q000379:methods*; D004952:Esters / Q000302:isolation & purification; D005638:Fruit / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D059625:Liquid-Liquid Extraction; D009812:Odorants / Q000032:analysis*; D009822:Oils, Volatile / Q000032:analysis / Q000302:isolation & purification*; D028321:Plant Preparations / Q000737:chemistry*; D052617:Solid Phase Microextraction; D013649:Taste; D013729:Terpenes / Q000302:isolation & purification; D055549:Volatile Organic Compounds / Q000032:analysis / Q000302:isolation & purification*
D004952:Esters; D009822:Oils, Volatile; D028321:Plant Preparations; D013729:Terpenes; D055549:Volatile Organic Compounds
dynamic headspace analysis; gas chromatography; mass spectrometry; solid-phase microextraction; solvent extraction