ABSTRACT: Kefir is fermented milk that has a unique flavor because of acetaldehyde, diacetyl, acetoin and ethanol. The aim of this study was to evaluate flavor and aroma compounds present in kefir. Two types of starter (Christian Hansen and Sacco) and three levels of temperatures (30, 33 and 35oC) were used for the preparation of kefir samples. The samples were analyzed for acetaldehyde, diacet...

Volatile compounds are important components of tea aroma, a key attribute of sensory quality. The present review examines the formation of aromatic volatiles of various kinds of teas and factors influencing the formation of tea volatiles, including tea cultivar, growing environment and agronomic practices, processing method and storage of tea. The determination of tea volatiles and the relation...

BACKGROUND The aim of this study was to evaluate the effect of the whole non-volatile wine matrix composition on the volatility of typical wine aroma compounds by comparing the slopes of regression lines of five deodorised and reconstituted wines with the slopes calculated for the same compounds in a control wine with no matrix effect. RESULTS The main effect observed was a reduction in the s...

The key aroma compounds and the organoleptic quality of two Chinese Syrah wines from the Yunnan Shangri-La region and Ningxia Helan mountain region were characterized. The most important eighty aroma-active compounds were identified by Gas Chromatography-Olfactometry. In both Syrah samples, ethyl 2-methylpropanoate, ethyl 3-methylbutanoate, 3-methylbutyl acetate, 2- and 3-methyl-1-butanol, ethy...

abstract: kefir is fermented milk that has a unique flavor because of acetaldehyde, diacetyl, acetoin and ethanol. the aim of this study was to evaluate flavor and aroma compounds present in kefir. two types of starter (christian hansen and sacco) and three levels of temperatures (30, 33 and 35oc) were used for the preparation of kefir samples. the samples were analyzed for acetaldehyde, diacet...

the effect of oleic acid (5 and 10% v/v) and xanthan gum (0.5 and 1% wt) on  partitioning and retention of ethyl acetate and diacetyl from two matrices with a different composition was investigated by applying static head space gas chromatography. two matrices with different composition have been developed: one containing carbohydrates (xanthan gum) and in the second one, called complex matrix,...

Development of malodourous compounds, hexanal and p-vinyl guaiacol (PVG), in UHT model liquid systems fortified with wholegrain oat were evaluated. Single and mixed systems using oat powder (3, 5, and 7% w/w), skim milk powder (SMP, 2.8% w/w) and sucrose (6.7% w/w) were subjected to UHT treatment and 29 days ambient storage. Both chromatographic analyses and panellists' perceived aroma intensit...

A headspace sampling method is described for concentrating milk volatiles onto a multi-channel open tubular silicone rubber trap (MCT) for thermal desorption into a GC-FID. Sections of the chromatographic profile, single peaks or combinations of compounds are recaptured with secondary MCTs during a subsequent run. The recaptured aroma is released in a controlled manner by heating the MCT in a p...

Galbanum oil is composed of monoterpenes in large amounts and pyrazines in small amounts. Although the monoterpenes are the main components of galbanum oil, they hardly contribute to the distinct galbanum aroma. The scanty amounts of pyrazines, in contrast, contribute significantly to the aroma. Considering the complexity and potency of the odor, the essential oil was assumed to contain so far ...