Comparison of volatile compounds in yoghurts made from cows’, buffaloes’, ewes’ and goats’ milks

Abstract

The composition of the volatile fraction of yoghurts made from cows’, buffaloes’, ewes’ and goats’ milks was investigated during the 28 days of storage at 4 °C using solid‐phase microextraction technique (SPME) and gas chromatography coupled to mass spectrometry analysis (GC/MS). A total of 34 volatile compounds were identified in yoghurts during their storage at 4 °C, including aldehydes, ketones, alcohols, esters, acids, terpenes, hydrocarbons and sulphur compounds. In this study, acetaldehyde, diacetyl and acetoin, considered as the major compounds of yoghurt, were detected in all yoghurts.

Recent analyses using solid phase microextraction in industries related to food made into or from liquids

“…For dairy products, fatty acid esters were usually formed though enzyme activity, especially in cheeses (Bergamini et al, 2010;Delgado et al, 2010Delgado et al, , 2011Wolf et al, 2010), or added as a flavoring in milks and yoghurt through direct addition or enzyme production (Erkaya & Ş engül, 2011;Gioacchini et al, 2010;Majcher et al, 2010;Soukoulis et al, 2010;Verzera et al, 2010;Vítová et al, 2010;. In fruit and vegetable processing, fatty acid esterification was identified from SPME analyses of cooked and stored potatoes (Blanda et al, 2010).…”

“…Acetaldehyde was considered the strongest contributor to yoghurt aroma (Soukoulis et al, 2010), as well as being the most concentrated aldehyde in some cheeses (Bergamini et al, 2010;Cais-Sokoli nska & Majcher, 2010;Majcher et al, 2010). Acetaldehyde was shown to be a marker of goats milk used to make yoghurt with the milk having much lower concentrations of both acetaldehyde and hexanal (Erkaya & Ş engül, 2011).…”

“…Specific aldehydes or ketones that have been used to optimize SPME techniques for monitoring food processing include: a) diacetyl, an aldehyde used to monitor the quality of butter, butter flavorings (Chen, Shirey, & Sidisky, 2010), and yoghurt maturation (Erkaya & Ş engül, 2011); b) 3-hydroxybutanone, a ketone used to optimize SPME analyses so as to monitor cheese maturation (Barba, Santa-Marìa, Flores, Herraiz, & Calvo, 2010); c) g-Decalactone and (E)-a-ionone, ketones used to distinguish between natural and adulterated samples of a variety of fruit flavor compounds in food and beverages (Ravid et al, 2010); and d) the aldehyde citronellal, used as a marker of different citrus species using a PDMS SPME fiber (Lin et al, 2010).…”

“…SPME analyses have also been used to identify fatty acids characteristic of particular food products. Relative concentrations of fatty acids were used to characterize cheese or yoghurt (Ampuero & Bosset, 2003;Erkaya & Ş engül, 2011). For example, only four fatty acids were needed to characterize Swiss cheese (Ampuero & Bosset, 2003), and the fatty acid profile of yoghurt was used to identify the animal that produced the milk (Erkaya & Ş engül, 2011).…”

“…Relative concentrations of fatty acids were used to characterize cheese or yoghurt (Ampuero & Bosset, 2003;Erkaya & Ş engül, 2011). For example, only four fatty acids were needed to characterize Swiss cheese (Ampuero & Bosset, 2003), and the fatty acid profile of yoghurt was used to identify the animal that produced the milk (Erkaya & Ş engül, 2011). In other studies, fatty acids were used: a) to discriminate between goat and dairy cheese with identification of hexanoic acid as the compound that was characteristic of the distinctive smell and taste of goat cheese (Mondello et al, 2005;Serhan, Linder, Hosri, & Fanni, 2010); b) to determine that fatty acids from four to eight carbon atoms plus acetic acid were the dominant aroma in non-fat cheese (Cais-Sokoli nska & Majcher, 2010); c) as part of a library of compounds to fingerprint the volatile aroma molecules of grapes (Forde et al, 2011), blackberries (Meret, Brat, Mertz, Lebrun, & Günata, 2011), apples (Abrodo et al, 2010), guava (Osorio, Forero, & Carriazo, 2011) or citrus (Cevallos-Cevallos, Garcìa-Torres, Etxeberria, & Reyes-DeCorcuera, 2010; Lin, Roan, Lee, & Chen, 2010).…”