Fat-Derived Volatiles of Various Products of Cows', Ewes', and Goats' Milk

Abstract

Raw milks and various dairy products from cows', ewes', and goats' milk were analyzed for fat-derived volatiles by headspace solid phase micro extraction-gas chromatography/mass spectrometry. In most products analyzed, free fatty acids of chain C4-C18, several carbonyl compounds, and lactones were detected. Moreover, acetic acid-a non fat-derived free fatty acid-and several ethyl esters were detected in some products. Raw cows', ewes', and goats' milks exhibited some qualitative and quantitative differences in their volatiles. Pasteurized cows' milk with 3.5% fat exhibited higher levels of most volatiles than that with 1.5% fat, while that with 0% fat exhibited the lowest levels. Only a few qualitative differences were observed among cultured milk and cows' and ewes' yoghurt, while the two yoghurts exhibited some quantitative differences. Levels of most volatiles decreased by decreasing the fat content of strained yoghurt (8.1, 2.1, and 0% fat). Cow and ewe sweet cream butters exhibited some differences in their volatiles. Twenty-day-old feta cheese exhibited higher levels of fat-derived volatiles than the ripened one (60 days old). Cow Gruyere-type cheese, ewe Gruyere-type cheese, and a goat semi-hard cheese exhibited qualitative and quantitative differences in their volatiles. Ewe and goat cheeses contained several ethyl esters, while cow cheese did not.

Characterization of volatile compounds and organic acids in ultra-high-temperature milk packaged in tetra brik cartons

“…A total of 43 VCs were identified in UHT milk, including 4 aldehydes, 5 alcohols, 10 ketones, 9 acids, 9 aromatic hydrocarbons, 3 nitrogenous, 2 sulfur containing compound, and 1 alkane hydrocarbon ( Table 3). The number of VOCs identified in UHT milk samples was greater than those in previous studies [4,8,11,13] where were ranged from 8 to 32. Nitrogenous containing compounds were the most abundant, accounting for 46.44% of total VOCs identified in all the UHT milk samples, followed by ketones (24.50%), acids (16.94%), aromatic hydrocarbons (9.35%), sulfur compounds (7.96%), alkane (5.37%), alcohols (2.94%), and aldehydes (0.99%) in decreasing order (Fig.…”

“…Free fatty acids of short-chain length could be produced from hydrolysis of milk triglycerides by heatresistant lipases or from lactose by heat treatment. Similarly, Vegas and Roussis [13] reported an increase in butanoic, hexanoic, octanoic, and decanoic acids in pasteurized milk compared to raw cow milk. Acids identified in this study have previously been found in milk pasteurized by microfiltration and ultrapasteurized milk with dominance of hexanoic and octanoic acids, respectively, [18,29,44] who indicated that pasteurization with microfiltration caused a greater increase in acids than pasteurization only.…”

“…[12] The content and profiles of VCs identified in UHT milk are related to the fat content of milk, the intensity of heat treatment, the homogenization process (pressure/temperature) and the storage conditions. [6,7,13,14] VCs are not only responsible for the characteristic flavor of a food, but also for its off-flavors. Knowledge of VCs in UHT milk will be important to determine the acceptability of the product to the consumer.…”

“…[16] SPME-gas chromatography-mass spectrometry (GC/MS) technique has been used in analysis of volatiles of milk. [4,13,17,18] In the present study, we sampled the UHT milks with the similar expiration date and fat content in order to elimination the effects of storage period and fat content on VCs. Therefore, we aimed to determine the changes in VCs and OA contents in the UHT milk samples with the similar basic nutrient components, packing materials, and the expiration date.…”

Importance of the Joint Use of Goat and Cow Milk in the Production of Soft Cheeses

“…Natural and climatic conditions of habitat and breeding of different animal species caused significant differences in the composition of milk [17]. The chemical composition The fluctuations in the main indicators of raw milk are associated with many factors.…”