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This work reports on monoamines (MA), diamines (DA) and polyamines (PA) as well as free amino acids (fAA) in nutritional supplements and infusions derived from green coffee beans. Samples were investigated using a ultra-high performance liquid chromatography UV/FLR method, which was validated regarding specificity, linearity, range, precision, accuracy and limits of detection and quantification. Nutritional supplements based on green coffee beans showed large amounts of total amines ranging from 1090 to 2593 mg/kg, with exceptional high levels of spermidine up to 724 mg/kg, and a content of fAA from 4004 to 12,389 mg/kg. Infusions brewed from green coffee beans showed much lower contents of amines (14–17 mg/L) and fAA (78–100 mg/L). However, if the customary edible portion was considered, infusions from green coffee were a mainly better source for MA and PA as well for fAA, compared to nutritional supplements. Tryptamine and tyramine were predominant as MA putrescine as DA, and spermidine as PA, respectively. Graphic abstract

Regarding the prospective investigation of food authenticity and adulteration the aim of the present study was the development and validation of a real-time PCR assay to identify hemp (Cannabis sativa) which has gained increasing importance as a valuable food ingredient. The assay targets a specific spacer DNA sequence in Cannabis sativa chloroplasts and detects 1.5 pg hemp DNA, which is equivalent to 18 copies/µL. Corresponding to the very low LOD (0.00031 ng/µL) the method allows the detection of hemp even in the infinitesimal concentration of contaminants. Due to a SNP in position 603, hemp can be identified unequivocally and discriminated from its closest relative hops (Humulus lupulus). The PCR method shows no cross-reactivity with 39 of 46 tested plant species. Low cross-reactivity with mulberry, stinging nettle, lavender, cornflower, wine, figs and hops can be neglected, because the Δ Ct-values are > 14, and the obtained Ct-values are beyond the cut-off for a positive assessment (Ct-values ≤ 33). Moreover, the suitability of the method to identify hemp as a food ingredient was proved by analysing diverse food products such as chocolate or cookies.

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.

Determination of antimicrobial wild-type minimum inhibitory concentration (MIC) distributions is a prerequisite before differentiating susceptible bacteria from bacteria with acquired resistance. The antimicrobial susceptibility was determined for 190 strains of eight species of the Lactobacillus delbrueckii group. These were L. acidophilus, L. amylovorus, L. crispatus, L. delbrueckii, L. helveticus, L. gallinarum, L. gasseri and L. johnsonii. For most antimicrobial agents a clear distinction between susceptible and resistant bacteria was observed. Tetracycline resistance was abundant among L. johnsonii and L. amylovorus strains isolated from animals, while the L. delbrueckii and L. helveticus strains isolated from dairy products, and L. gasseri isolated from humans, rarely contained acquired resistance.

We have established an electrophoretic method to evaluate proteolysis in Parmesan cheese by means of an objective ripening index. The separation of caseins by alkaline polyacrylamide gel electrophoresis (PAGE) (12% T, 2.6% C, pH 8.9, 5 M urea) is followed by the densitometric analysis of theγ- andβ-casein fractions. The relationship between the resulting coefficients (γ-Cn/β-Cn) and the age of reference samples of Original Italian Grana Padano (6–22 months) was linear up to 15 months, allowing an evaluation of the extent of proteolysis and therefore a deduction of the age of the Parmesan samples analysed. Based on this calibration we propose to use a threshold level of 1.3 (γ-Cn/β-Cn) to verify the required age, i.e. 12 months, of Parmesan cheese, retailed as a loaf or prepacked slices. Commercially grated Parmesan samples may contain ≤20% cheese rind, which has a very low degree of casein breakdown. So a threshold level of 0.8 (γ-Cn/β-Cn) is proposed for all grated Parmesan products. The preparation of reference solutions with defined coefficients (γ-Cn/β-Cn), corresponding to the proteolysis indices of reference samples of different aged Grana Padano is described. The coefficients (γ-Cn/β-Cn) as well as theβ-casein content of two additional series of reference samples and of 49 commercial Parmesan samples taken from retail outlets in Austria and Italy are presented.