| Abstract
| - The effects of high hydrostatic pressure on volatile generation in milk were investigated in this study.Raw milk samples were treated under different pressures (482, 586, and 620 MPa), temperatures(25 and 60 °C), and holding times (1, 3, and 5 min). Samples submitted to heat treatments alone(25, 60, and 80 °C for 1, 3, and 5 min) were used for comparison. Trace volatile sulfur compoundswere analyzed using solid-phase microextraction (SPME) and gas chromatography (GC) with pulsed-flame photometric detection (PFPD), whereas the rest of the volatile compounds were analyzed usingSPME-GC with flame ionization detection (FID). Multivariate analysis of variance (MANOVA) andprincipal component analysis (PCA) were used to study the effect of pressure, temperature, andtime on volatile generation. Relative concentration increases of 27 selected volatile compounds werecompared to an untreated sample. It was found that pressure, temperature, and time, as well astheir interactions, all had significant effects (P< 0.001) on volatile generation in milk. Pressure andtime effects were significant at 60 °C, whereas their effects were almost negligible at 25 °C. ThePCA plot indicated that the volatile generation of pressure-heated samples at 60 °C was differentfrom that of heated-alone samples. Heat treatment tended to promote the formation of methanethiol,hydrogen sulfide, methyl ketones, and aldehydes, whereas high-pressure treatment favored theformation of hydrogen sulfide and aldehydes. Keywords: Milk; high-pressure processing; volatile; volatile sulfur compounds
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