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Pasteurisation is a common technique to achieve microbial stability of beer. In dry hopped beer, pasteurisation is the ultimate measure to assure product quality and consumer safety. To gain insights into the effects of pasteurisation on the chemistry of hoppy ales the time related changes of aldehydes, terpenes, terpenoids and esters in an unpasteurised and pasteurised session India Pale Ale (SIPA), two IPAs, and a double IPA (DIPA) were monitored. The ales were stored at 4 °C and 20 °C for 52 wk to evaluate chemical differences between the two treatments. It was found that pasteurisation led to an immediate increase of staling aldehydes (i.e., furfural and 2-methylpropanal), a decrease of fermentation esters (e.g. ethyl octanoate) and hop related esters (e.g. 2-methylbutyl isobutyrate) in fresh beer, while terpenes and terpenoids were hardly affected. When the beers were stored, unpasteurised ales were chemically less stable compared to the pasteurised ones. Differences between pasteurised and unpasteurised ales were dependent on storage temperature. The results of this study highlight that pasteurisation is favourable when aiming to achieve an increased shelf life of up to 12 months, as the negative influence of the heat impact is compensated after 1 month of storage at ambient (20 °C) temperature. [ABSTRACT FROM AUTHOR]

Obesity is a major health problem in dogs and is strongly associated with an increased risk of chronic inflammatory and metabolic diseases. The microaerophilic human gut bacterium Akkermansia muciniphila has been proposed as a potential preventive and therapeutic agent against obesity in both humans and mice; however, the protective effects of human-derived A. muciniphila against canine obesity remain unstudied. We previously demonstrated that the heat-killed A. muciniphila strain EB-AMDK19 (AMDK19-HK) isolated from the faeces of a healthy Korean exerts similar protective effects as the live bacterium in mice with high-fat-diet (HFD)-induced obesity. Here, we evaluated the effects of AMDK19-HK on body weight, body fat mass, haematological and biochemical parameters, and faecal microbiota composition in beagles fed an HFD for 12 weeks. AMDK19-HK supplementation effectively suppressed body weight increase, body fat deposition and serum triglyceride increase in the canine model; however, no significant changes in the overall haematological and biochemical parameters were observed, reflecting the direct anti-obesity effect of AMDK19-HK. Additionally, 16S rRNA gene sequencing revealed that AMDK19-HK supplementation induced significant changes in the faecal bacterial community, with an increased abundance of Firmicutes and a decreased abundance of Bacteroidota. These results suggest that AMDK19-HK can be used as a dietary supplement to counteract diet-induced overweight in dogs. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the effects of heat on macrocyclic lactone residues in cows' milk. Ivermectin, abamectin, doramectin, eprinomectin and moxidectin were added to raw milk in three concentrations. The milk was then pasteurised (40 seconds at 74°C or 1 minute at 80°C) and boiled (10 minutes at 100°C). The analyses were performed with a validated method: LC-MS/MS. Thermal treatment resulted in a statistically significant decrease in the abamectin, eprinomectin, and moxidectin concentrations in the milk; however, the residues did not completely degrade. Boiling resulted in a greater decrease in the moxidectin concentrations than was observed with pasteurisation. The high pasteurisation and boiling processes had a greater effect on the eprinomectin residues than did the low pasteurisation process. The pasteurisation and boiling processes did not have an effect on the doramectin and ivermectin. The study concluded that the macrocyclic lactones are generally resistant to such processes. [ABSTRACT FROM AUTHOR]

The presence of antibiotics in raw milk and milk derivatives poses a threat to human health and can negatively affect the dairy industry. Therefore, the main object of this study was to investigate the transfer of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from raw, experimental milk contaminated with tetracyclines (TCs) to different dairy products: cream, butter, buttermilk, sour milk, whey, curd and cheese. Additionally the effect of the skimming process on TCs concentrations was tested, as well as the influence of lowtemperature long-time pasteurisation. The analyses of TCs in milk and dairy products were performed by an LC-MS/MS method. In order to determine TCs residues in dairy products, an analytical method was developed with the same extraction step for all matrices. TCs molecules were inhomogenously distributed between the milk derivative fractions. The highest concentrations were determined in curd and cheese in the ranges 320-482 µg/kg and 280-561 µg/kg, respectively. Low levels of TCs in butter and whey were observed (11.8-41.2 µg/kg). TCs were found in sour milk (66.0-111 µg/kg), cream (85.0-115 µg/kg) and buttermilk (196-221 µg/kg) at much higher levels than in butter and whey, but lower than in curd and cheese. During the skimming process, the highest yield of cream was obtained after the raw milk was held at 2-8°C for 24 h. The differences in concentrations of TCs between whole milk and skimmed milk, expressed as percentages of recovery, were below 19% (recoveries in excess of 81%). The highest content was observed in milk and cream skimmed at 2-8°C. The degradation percentages for TCs during the pasteurisation process (63°C for 30 min) were below 19%. [ABSTRACT FROM AUTHOR]

Food products are dielectric materials. The ability to store and dissipate electromagnetic energy of food in dielectric heating is determined by its dielectric properties. To develop pasteurisation protocols based on radio frequency (RF) and microwave (MW) heating of chili powder, dielectric properties of chili powder were measured using an open-ended coaxial-line probe and an impedance analyzer over a frequency range from 8 to 3000 MHz. Penetration depth of chili powder was calculated at five selected frequencies. Results showed that the dielectric properties of chili powder decreased with increase in frequency from 8 to 3000 MHz, but increased with increase in moisture content from 4 to 15% (w. b.) and with increase in temperature from 25 to 85°C. Dielectric constant and loss factor of different density samples showed little difference at low temperature, but large difference at high temperature. RF waves have larger penetration depth in chili powder than MW, and therefore could result in better heating uniformity especially for thicker samples during pasteurisation process. Geometry of sample and heating runaway phenomena may also affect the application of RF pasteurisation for foods. The relationship between moisture content, temperature, and dielectric properties of chili powder at 13.56, 27.12, 40.68, 915 and 2450 MHz can be described by third-order polynomial models with high coefficient of determination (R2>0.89), which can be used to predict temperature- and moisture-dependent dielectric constant and loss factor of chili powder with high accuracy. [ABSTRACT FROM AUTHOR]

Background: Human milk oligosaccharides (HMOs) have important protective functions in human milk. A low-cost remote pasteurisation temperature-monitoring system has been designed using FoneAstra, a cell phone-based networked sensing system to monitor simulated flash heat pasteurisation. Aim: To compare the pasteurisation effect on HMOs of the FoneAstra FH method with the current Sterifeed Holder method used by human milk banks. Methods: Donor human milk samples (n = 48) were obtained from a human milk bank and pasteurised using the two pasteurisation methods. HMOs were purified from samples and labelled before separation using high-performance liquid chromatography. Concentrations of total HMOs, sialylated and fucosylated HMOs and individual HMOs using the two pasteurisation methods were compared using repeated-measures ANOVA. Results: The study demonstrated no difference in total concentration of HMOs between the two pasteurisation methods and a small but significant increase in the total concentration of HMOs regardless of pasteurisation methods compared with controls (unpasteurised samples) (p<0.0001). Conclusion: The FoneAstra FH pasteurisation system does not negatively affect oligosaccharides in human milk and therefore is a possible alternative for providing safely sterilised human milk for low- and middle-income countries. [ABSTRACT FROM AUTHOR]

The effects of supercritical CO2(SC-CO2) on the microbiological, sensory (taste, odour, and colour), nutritional (vitamin C content), and physical (cloud, total acidity, pH, and °Brix) qualities of orange juice were studied. The CO2treatment was performed in a 1 litre capacity double-walled reactor equipped with a magnetic stirring system. Freshly extracted orange juice was treated with supercritical CO2, pasteurised at 90°C, or left untreated. There were no significant differences in the sensory attributes and physical qualities between the CO2treated juice and freshly extracted juice. The CO2treated juice retained 88% of its vitamin C, while the pasteurised juice was notably different from the fresh juice and preserved only 57% of its vitamin C content. After 8 weeks of storage at 4°C, there was no microbial growth in the CO2treated juice. [ABSTRACT FROM AUTHOR]

Groups of rats were immunised intraperitoneally with 0.5 ml of raw milk, skim milk, pasteurised milk or pasteurised/homogenised milk. On day 14, animals were boosted with identical preparations, and serum samples were collected on day 28 for the measurement of IgG antibodies directed against milk plasma proteins. Samples were assayed for antibodies to casein, beta-lactoglobulin, bovine gamma globulin and bovine serum albumin. Significantly higher concentrations of antibodies of all specificities were detected in the serum of animals immunised with pasteurised/homogenised milk compared with animals immunised with raw or skim milk. Higher concentrations of antibodies were also seen in the group immunised with pasteurised/homogenised milk than the group immunised with pasteurised milk, although significant differences were only seen in the response to casein (p < 0.01). Additional animals were twice immunised with either raw milk fortified with keyhole limpet hemocyanin (KLH), or pasteurised/homogenised milk which had been fortified with KLH prior to processing. Such treatment significantly enhanced the immunogenicity of the KLH (p < 0.05). These results raise the possibility that homogenisation may similarly effect the way in which the human immune system interacts with cows' milk proteins in the gastrointestinal tract, and suggest that milk processing may be an important variable to consider in studies of human allergy to cows' milk proteins. [ABSTRACT FROM AUTHOR]