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Despite the increasing economic importance of goat’s milk in Europe, no current data on the chemical composition and physical properties of this milk species are available in Austria. Thus, milk samples of six dairy goat breeds in Austria (Bunte Deutsche Edelziege, Pinzgauer Ziege, Saanenziege, Strahlenziege, Toggenburger Ziege, Weise Deutsche Edelziege) were analysed for physicochemical characteristics for 8 months from March to October. Considerable seasonal variations, but nearly no statistically significant differences between milk samples from these six goat breeds were observed regarding most parameters. The mean values obtained for all breeds during the whole season were as follows: pH 6.55, freezing point depression 0.549 °C, ash 0.828%, total solids 12.24% (w/w), crude protein 3.35% (w/w), casein 2.40% (w/w), whey protein 0.63% (w/w), urea 0.325 g⋅L−1, fat 3.67%, lactose 4.23%, citric acid 0.913 g⋅L−1, phosphorus 1.088 g⋅L−1, chloride 1.708 g⋅L−1, sodium 0.304 g⋅L−1, potassium 1.759 g⋅L−1, calcium 1.256 g⋅L−1, magnesium 0.128 g⋅L−1, orotic acid 13.59 mg⋅kg−1, β-carotene 0.419 mg⋅L−1, retinol 0.502 mg⋅L−1, riboflavin 1.050 mg⋅L−1, and cholesterol 12.4 mg⋅100 g−1 milk, respectively. The studies on fatty acid profiles revealed the following mean values: C4:0 2.73%, C6:0 2.10%, C8:0 1.86%, C10:0 5.80%, C12:0 2.52%, C14:0 7.07%, C16:0 23.73%, C18:0 11.84%, and C18:1 28.14%. Unexpected high levels were obtained for C18:2 (5.06%) and C18:3 (0.59 %), respectively. This work provides an updated information on the current physicochemical characteristics of goat’s milk in Austria, which can be of great importance in the fields of dairy and food technology, nutrition science, and food analysis, respectively.

Recent trends to extend the shelf life of pasteurized milk, without the negative flavour normally associated with ultra-high-temperature (UHT) milk, have resulted in the development of extended shelf life (ESL) milk. Acid-soluble β-lactoglobulin (β-Lg) and furosine contents were chosen as relevant indicators for heat load of ESL milk products. RP-HPLC methods were developed using the same column (Symmetry 300™, Waters), which enabled the separation of whey proteins within 22 min; furosine was analysed using ion-pair RP-HPLC within 8 min. Electrophoresis was used as a high-throughput and cost-effective screening method to assess the impact of thermal processes on milk and to distinguish different categories of heat-treated milk samples. Liquid milk samples (n = 128; including 7 raw, 33 pasteurized, 71 ESL, and 17 UHT milk samples) were obtained from retail outlets in Austria and analysed. Only 45% of the analysed samples designated as ESL milk showed furosine contents 1800 mg·L−1 milk, which had been discussed as threshold levels for ESL milk. A further 55% of the analysed ESL milk samples had low acid-soluble β-Lg ( 40 mg·100 g−1 protein), levels comparable to the excessive heat load of UHT milk. Thus, there is an urgent need for an EU regulation to define legal limits for the tolerable heat load of ESL milk as soon as possible.