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Insects are rich in major nutrients, such as protein and fat. Recently, minor nutrients like vitamins have become the subjects of interest in insects. Hence, this study reports on the development and validation of a method for the determination of vitamin B12 in mealworm (Tenebrio molitor larvae), cricket (Gryllus assimilis), grasshopper (Locusta migratoria) and cockroach (Shelfordella lateralis), using an ultra-high performance liquid chromatography approach with preliminary immunoaffinity chromatography sample preparation. The method was validated regarding linearity, specificity, accuracy and precision, as well as limits of detection/quantification, and was found to be satisfactory for the desired application. Found levels of vitamin B12 were 1.08 µg/100 g for mealworm, 2.88 µg/100 g for cricket, 0.84 µg/100 g for grasshopper, and 13.2 µg/100 g dry weight for cockroach, representing the first validated report on the content of vitamin B12 in edible insects. Observed interferences are likely caused by the presence of pseudovitamin B12.

Biogenic amines (BA) in various commercial cheese samples (n = 151) representing most common cheese varieties were determined using UHPLC. In general, cumulative BA levels varied to a great extent with exceptional samples having amounts up to 150–313 mg/100 g cheese, whereas only 5% of the analysed cheeses showed total concentrations higher than 90 mg/100 g (median 5.7 mg/100 g). Histamine was found in 79% of all samples, with maximum concentrations up to 116 mg/100 g, but only 5% of the cheeses had a histamine level above 17 mg/100 g (median 0.9 mg/100 g). For tyramine (72% occurrence), highest values were found for some acid-curd cheeses (up to 160 mg/100 g) and certain “mountain cheeses” (median 1.0 mg/100 g). Putrescine was detected in 70% of the cheeses (up to 84 mg/100 g for some acid-curd cheeses; median 0.6 mg/100 g). Cadaverine was found in 48% of the samples, with highest concentrations for some acid-curd cheeses (median 0.2 mg/100 g). Tryptamine had the lowest occurrence (15%) and a median concentration of 0.3 mg/100 g.

As raw cow's milk possesses a limited shelf-life and can also pose a threat to the consumer's health, thermal preservation techniques are customary nowadays. A range of compounds can be used for the assessment of successfulness of such treatments, so-called time temperature integrators (TTIs). Although most water-soluble vitamins are known to be depleted during heat exposure in milk, their application as TTI hasn't been investigated yet. Especially vitamin B6 with its various possible vitamers (chemical different forms that exhibit vitamin activity) might be a suitable system for a new vitamin-based TTI. Therefore, the applicability of B6 vitamers in cow's milk as a TTI system was to be evaluated in this study. A recently developed ultra-high performance liquid chromatography method for the simultaneous assessment of all relevant B6 vitamers in cow's milk was used to characterize the status and composition of B6 vitamers in a market survey (n = 78) from Austria, Germany and Czech Republic, comprising milk produced by various thermal and non-thermal preservation techniques such as pasteurization, extended shelf life, ultra-high temperature (UHT). Examining generated data using classification and regression decision trees, discrimination of UHT milk from other preservation techniques, based on the ratio of B6 vitamers was possible. Hence, representing the first report for process authentication of cow's milk based on the composition of minor nutrients (B6 vitamers).

Awassi dairy sheep farmers in the Middle East are facing high feed costs, particularly during the milk production season, along with large fluctuation in grain and straw prices. Incorporating agro-industrial byproducts into the diet of Awassi dairy sheep can help to balance diets and decrease costs. But it may affect milk quality through changes in the fatty acid profile. Six experimental diets were compared to a control diet in the research station of the International Center for Agricultural Research in the Dry Areas (ICARDA) in Tal Hadya, Syria. Milking Awassi ewes (n = 56) were used to test six experimental diets, in which supplements comprised molasses, sugar beet pulp, or cotton seed cake to a traditional control diet contained barley, wheat bran, and barley straw. Milk samples were collected on a weekly basis from April to June. The daily milk production and fat content were enhanced in diets containing urea-treated wheat straw (P

The aim of this study was to develop a high-throughput UHPLC method for the determination vitamin B1 active compounds; thiamin, thiamin monophosphate and thiamin diphosphate in bovine milk. In order to sustain the native vitamin B1 phosphorus esters, sample preparation is crucial. Various acids as well as commonly used enzymes and their enzyme mixtures were compared. Method accuracy was confirmed using certified reference material as well as comparison with the corresponding CEN method, and was found to be satisfactory. Studied milk samples showed significant amounts of thiamin monophosphate, which can make up to 53.9% of the total vitamin B1 content in commercial milk, and up to 78% in raw milk. Moreover, a tremendous variation of the total content of vitamin B1 was observed between single cows, which ranged from 0.24 mg/L up to 0.54 mg/L of total vitamin B1.

Besides sensorial assays for quantifying pungent components in chilies, nowadays mainly HPLC methods focus on the determination of individual capsaicinoids. Compared to HPLC, ultra-highperformance chromatography (UHPLC) enables shorter runtimes and enhanced resolution. Thus, the aim of this work was to establish a rapid UHPLC method for the determination of capsaicin and dihydrocapsaicin, the most powerful pungent capsaicinoids found in chili fruits. The developed UHPLC method features a significantly reduced separation time (1.7 min) and high chromatographic resolution, hence presenting a feasible approach for high-throughput pungency profiling. Compared to UV, fluorescence detection showed superior sensitivity with a limit of quantification for capsaicin of 0.160 μg g −1 and 0.175 μg g −1 for dihydrocapsaicin and proving suitable for analysing even very low pungency chili products. Moreover, to investigate the massive variability between chilies, typical varieties that were grown in Austria were characterized for their intrinsic pungency, with total capsaicinoids amounts ranging from 213 μg g −1 for Jalapeno to 28200 μg g −1 dry weight for ‘Bhut Jolokia’. Moreover, analyses of different fruit compartments showed tremendous deviation between the pericarp and the placenta with seeds.

Thermal time integrators (TTIs) are useful tools to describe the heat load of pasteurized, Ultra-high temperature (UHT) and emerging Extended Shelf Life (ESL) milk, which can be produced using filtration or direct/indirect heat treatment. However, threshold limits are mandatory for β-lactoglobulin in pasteurized and UHT milk, but currently not for ESL milk, for which the Austrian Food Codex grants a transition period till 2018 for dairies using indirect heating technologies. The objective of this study was to compare two sample sets of bovine milk retailed in Austria, purchased in 2012 (n = 71) and 2015 (n = 80) including pasteurized, UHT and differently processed ESL milk samples. Furosine, acid-soluble α-lactalbumin and β-lactoglobulin were determined with RP-HPLC, and lactulose enzymatically. Results were not significantly different comparing both years, but rather highlight the significance and suitability of these TTIs to distinguish between varying heat load applied on milk. Using furosine, lactulose and α-lactalbumin, a differentiation of pasteurized, filtered and directly heated ESL milk from indirectly heated ESL milk as well as from UHT milk is possible, whereas β-lactoglobulin allowed the discrimination of directly heated ESL milk from filtered ESL milk and pasteurized milk, respectively.

The concentration of the artificial compound furosine in liquid milk can be used as an indicator to assess the heat load applied onto the product, which allows discrimination between differently processed milk (pasteurized, Extended Shelf Life (ESL) milk, Ultra-High Temperature (UHT) treated milk). In this work, a new UHPLC method for the rapid determination of furosine in 2 min only (total runtime 6 min) is presented, using PDA detection at 280 nm. The method was validated for the analysis of liquid milk samples regarding linearity, instrumentation precision, limits of detection and quantification, repeatability of sample work-up and recovery. Moreover, the method was compared to an existing RP-HPLC method. Selected commercial liquid milk samples (n = 36) were analyzed, showing lowest furosine amounts for pasteurized milk, whereas highest amounts were found in UHT milk. For ESL milk, quite diverse concentrations were analyzed ranging from 11.70 up to 115.16 mg furosine 100 g−1 protein, illustrating the different processing technologies of this category with lowest amounts for filtered ESL milk, followed by directly heated, and indirectly heated ESL milk samples, respectively.

Soybean seed is one of the richest food sources of spermidine and other polyamines. Recent findings from human and animal models have confirmed spermidine as a potential anti-aging substance acting through the initiation of autophagy pathways as well as through antioxidant and anti-inflammatory properties. As this might be of relevance for selecting soybeans for soy food production, the present research addresses the natural variation of spermidine concentration of soybean to determine the influences of genotype and environmental factors on spermidine and other polyamines, and to study possible relationships between spermidine and major seed quality traits. Sixteen early maturity soybean genotypes were grown near Vienna, Austria for three seasons, and harvest samples were subject to ultra-high performance liquid chromatography (UHPLC) for determining concentrations of polyamines and free amino acids. Based on individual samples, spermidine concentration ranged between 167 and 291 mg kg−1 dry seed, and both genotype and growing season significantly affected spermidine level. Spermidine concentration was closely correlated to putrescine but was not related to seed protein content or other major seed constituents determined by NIRS analysis. These results demonstrate the feasibility of plant breeding approaches to modify the spermidine level of soybean which might support the future development of functional soy foods.

This study provides a direct comparability between milk from cows fed hay or silage produced from the same parent plant material; the influence of feeding either hay or silage on amounts of various milk components was investigated. To give an overview regarding differences in milk composition, protein fractions, free amino acids, polyamines and biogenic amines as well as fatty acid profile and sensory properties were analysed. Moreover, the content of vitamin E and four different B-vitamins (B1, B2, B6 and B12) was determined. Results showed that there are some significant differences between hay milk and silo milk, especially regarding certain key nutrients. Linoleic acid, α-linolenic acid, lysine and putrescine showed higher concentrations in hay milk, while vitamin B12 and spermine were increased in silo milk. Sensory analysis showed that feeding of silage had a significant influence on colour (yellow), consistency and odour intensity, which were more pronounced in silo milk.

Three heat load indicators, i.e., furosine, lactulose and acid-soluble β-lactoglobulin, were determined in whipping cream samples purchased from Austrian market ( n = 33), as well as commercial samples obtained directly from one Austrian dairy company (one brand, n = 25). Furosine contents were 47.8 ± 14.0, 72.2 ± 36.6, and 172.5 ± 17.7 mg 100 g −1 protein, and β-lactoglobulin contents were 143 ± 91, 195 ± 150, and 89 ± 31 mg L −1 for retailed pasteurised, extended shelf life (ESL), and ultra-high temperature (UHT) cream samples, respectively. Lactulose concentrations (analysed enzymatically) were 29 ± 10, 56 ± 41, and 201 ± 24 mg L −1 for pasteurised, ESL and UHT cream samples, respectively. Linear correlation obtained for furosine and lactulose concentrations indicated that these indicators can reliably assess the heat load of pasteurised, ESL and UHT cream samples, whereas β-lactoglobulin was definitely not appropriate to discriminate between these heating categories.

Since only isoflavone aglycones are considered to be bioactive, the determination of total aglycones that are released from conjugated isoflavones after hydrolytic treatment may facilitate an objective alternative for quantifying isoflavone contents in soy products. Given this major benefit, a new ultra-high pressure liquid chromatography (UV-UPLC™) method was developed for the fast and reliable determination of total aglycones in soybeans (daidzein, glycitein, and genistein) after enzymatic hydrolysis applying helix pomatia digestive juice. Capitalizing on the enhanced performance of UPLC™, aglycones were separated within 3 min only, with a total runtime of 8 min till the next injection. Thus, especially compared to HPLC protocols, UPLC™ proved to be superior due to significantly shorter runtimes and accordingly increasing sample throughput. Additionally, regarding the performed validation (linearity, precision, recovery, selectivity, and robustness), the established method proved to be suitable for quantifying total aglycones in soybeans. Moreover, method applicability was demonstrated by analyzing 23 commercial soybean cultivars for their isoflavone contents. Cumulative aglycone levels ranged from 100 to 255 mg per 100 g, hence implying an average ratio of 52%, 41%, and 7% of total isoflavones for genistein, daidzein and glycitein, respectively. However, for some soybeans, other distinct aglycone distributions were observed as well.

Physico-chemical characteristics of sheep and goat milk in Austria as influenced by seasonal effects and regional differences were investigated. Considerable seasonal variations were observed regarding most constituents. Sheep milk from three different dairy plants showed very similar chemical composition and physical properties, whereas average means of sheep milk were significantly different from goat milk except for freezing point, pH, and a few fatty acids (C12:0, C18:0, C18:1). The mean values obtained for sheep and goat milk during the whole season were: pH 6.59/6.59, freezing point −0.544/−0.542 °C, ash 0.853/0.813%, total solids 15.78/11.70%, crude protein 5.21/3.15%, casein 3.98/2.39%, whey protein 0.92/0.52%, urea 0.432/0.335 g L−1, fat 5.75/3.74%, lactose 4.64/4.32%, citric acid 1.535/1.018 g L−1, phosphorus 1.454/1.009 g L−1, chloride 1.196/1.755 g L−1, sodium 0.442/0.317 g L−1, potassium 1.248/2.015 g L−1, calcium 1.846/1.288 g L−1, magnesium 0.192/0.138 g L−1, orotic acid 17.02/12.09 mg kg−1,and cholesterol 11.6/9.8 mg 100 g−1 milk, respectively.

Fifty samples consisted of 24 maize kernels and 26 maize based-food products from retail market in Yogyakarta, Indonesia were analysed for deoxynivalenol (DON) using high performance liquid chromatography (HPLC) combined with ultraviolet detection after immunoaffinity column (IAC) clean-up process. Prior to use, performance of the analytical method was evaluated in term of recovery, repeatability, and detection limit. The recoveries of DON in spiked samples (50–360 μg DON/kg sample) were obtained in a range of 70.9–97.3% with relative standard deviation (RSD) for repeatability within a day less than 16%. Limit of detection based on the response ratio of signal to noise (3/1) was noted being 20 μg DON/kg sample. All analysed samples contained DON ranging between 47 and 348 μg/kg with median and means of 111.0 and 124.6 μg/kg, respectively. The contamination of DON in the studied samples may not be taken into account as hazard for human and animal health since the concentrations were lower than maximum limit of DON contamination in foodstuffs (500 μg/kg) established by European Commission (2006).

Probiotic enterococci are frequently encountered as additives in animal nutrition, but no fast standardized methods for their unambiguous identification at strain level exist. Six polymerase chain reaction (PCR)-based methods previously described for similar tasks but other genera were evaluated concerning their suitability for the rapid, stringent and reliable identification of Enterococcus at strain level. The most appropriate method should facilitate the instant identification of isolates from animal feeds and should be applicable in routine quality control. Amplified ribosomal DNA analysis (ARDRA), internally transcribed spacer region (ITS)-PCR, randomly amplified polymorphic DNA (RAPD)-PCR, repetitive element sequence based (rep)-PCR, tRNA intergenic spacer PCR and 16S rRNA gene typing were investigated with 74 Enterococcus, mainly E. faecium, strains representing 11 species. RAPD-PCR proved superior by discriminating at the strain level. Depending on the enzyme, ARDRA yielded fingerprints specific for a species or even single strains. The remaining methods successfully identified enterococci at the genus level.

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.

There is urgent need for having available suitable methods and data regarding the susceptibility levels of antibiotic resistant and sensitive strains of bifidobacteria. Based on a defined standard operation procedure, agar disc diffusion and broth microdilution were compared in order to evaluate the antimicrobial susceptibility profiles of 82 B. pseudolongum and 80 B. thermophilum strains mainly originating from the meat production chain. The methods that were assessed showed interpretable agreement within this study. The disc diffusion zone diameters are highly reproducible making the method a useful alternative to broth microdilution for antimicrobial susceptibility screening of bifidobacteria.

Fifteen new isolates from pig faeces were identified as Bifidobacterium animalis subsp. lactis by polymerase chain reaction (PCR) using primers specific for this subspecies. Ten of the isolates could be differentiated at strain level by randomly amplified polymorphic DNA (RAPD) analysis and pulsed-field gel electrophoresis (PFGE). These new strains were different from the type strain and other reference strains of this subspecies, and from all commercial dairy strains with probiotic functionality. Thus, possibly some of the isolates are potential candidates for new probiotic Bifidobacterium strains that can be unambiguously identified by RAPD-PCR and PFGE, which could be of interest for the food industry. In contrast, reference strains and commercial dairy strains revealed great genetic homogeneity, showing almost identical DNA fingerprints using RAPD-PCR and PFGE. Some reference strains and all commercial probiotic strains that had been originally designated as B. animalis or B. lactis have to be assigned to B. animalis subsp. lactis to be correctly labelled.

Different methods were applied to standard mixtures of milk from different species and to model cheeses of different ages to study their applicability for the detection of cows’ milk and determination of the percentage of cows’ milk in mixed milk cheeses. Urea–polyacrylamide gel electrophoresis (urea–PAGE) and anion-exchange high performance liquid chromatography (HPLC) of caseins was restricted to the control of the adulteration of milk. Isoelectric focusing (IEF) of γ-caseins according the EU reference method was well suited for detection of cows’ milk even in matured cheese, but could not discriminate ewes’ milk from goats’ milk. IEF and cation-exchange HPLC of para-κ-caseins were appropriate for differentiation of bovine, ovine and caprine milk. Urea–PAGE and IEF of whey proteins was useful for the species authentication of whey cheeses. Polymerase chain reaction using species–specific primers was a highly sensitive technique for the qualitative detection of cows’ milk even in overripe mixed cheese.

A rapid ultra-high performance liquid chromatography (UHPLC) protocol for the determination of amino acids as their respective 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatives was successfully applied for assessing free amino acid levels in commercial cheese samples representing typical product groups (ripening protocols) in cheesemaking. Based on the Waters AccQ.Tag™ method as a high performance liquid chromatography (HPLC) amino acid solution designed for hydrolyzate analyses, method adaptation onto UHPLC was performed, and detection of AQC derivatives was changed from former fluorescence (λ(Ex) 250 nm/λ(Em) 395 nm) to UV (254 nm). Compared to the original HPLC method, UHPLC proved to be superior by facilitating excellent separations of 18 amino acids within 12 min only, thus demonstrating significantly shortened runtimes (35 min for HPLC) while retaining the original separation chemistry and amino acid elution pattern. Free amino acid levels of the analyzed cheese samples showed a high extent of variability depending on the cheese type, with highest total amounts found for original Italian extra-hard cheeses (up to 9,000 mg/100 g) and lowest for surface mold- or bacterial smear-ripened soft cheeses (200-600 mg/100 g). Despite the intrinsic variability in both total and specific concentrations, the established UHPLC method enabled reliable and interference-free amino acid profiling throughout all cheese types, thus demonstrating a valuable tool to generate high quality data for the characterization of cheese ripening.