Mari Hakala

Determination of androstenone in pig fat using packed column supercritical fluid chromatography–mass spectrometry

Packed column supercritical fluid chromatography (SFC) in combination with atmospheric pressure chemical ionisation mass spectrometry was applied to the analysis of androstenone in pig fat samples. Liquefied fat samples were dissolved in dichloromethane and analysed directly by SFC without any sample purification. Chromatographic separation was achieved with a density/pressure gradient using pure carbon dioxide as the mobile phase and the analysis resulted in a quantitation limit of 0.25 microg/g with 1 microl injection volume. Good agreement was found between the SFC method and time-resolved fluoroimmunoassay by the analysis of 15 boar back fat samples.

Headspace FT-IR Analysis of Rapeseed Oil Oxidation

Volatile compounds formed by oxidation of rapeseed oil at 60 °C in open beakers were studied as a function of time over 289 h. A direct inlet gas-phase FT-IR method was introduced and compounds indicating lipid oxidation were detected and quantified. The development of 1,3,5-trimethylbenzene, 2,4-hexadienal, 2-methyl-1,3-butadiene, 2-methyltetrahydrofuran, acetic acid, methyl cyclopentane, methyl hexanoate, n-butanal, n-hexanal, n-octanal, n-propanal, and trans, trans-2,4-heptadienal was followed. The results showed that gas-phase FT-IR is a potential method of fast analysis for monitoring oil quality. Headspace-gas chromatography-mass spectrometry (HS-GC-MS) was used for compound identification.

Effect of baking process and storage on volatile composition of flaxseed breads

Abstract Volatiles of flaxseed oil, low fat crushed grains and three bakery products containing flaxseed in its different forms were analysed by GC-MS. Preliminary comparison of volatile compounds was made between freshly baked and stored products. The identified volatile compounds were mainly aldehydes, ketones and alcohols. Oxidative degradation of flaxseed oil was also monitored with rancidity tests during storage.

Effect of malolactic fermentation on the volatile aroma compounds in four sea buckthorn varieties

Abstract Volatile compound composition of sea buckthorn juice headspace was investigated before and after malolactic fermentation of the juice. Ethyl acetate, 3-methylbutanol and 3-methylbutyl acetate were formed in abundance during fermentation, whereas concentrations of ethyl 2-methypropanoate, ethyl 3-methylbutanoate, ethyl hexanoate and ethyl octanoate decreased.