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The research was performed to investigate the effect of high hydrostatic pressure low temperature (HHPLT) on Listeria innocua in Ringer's solution (RS) and raw milk (RM). The physicochemical properties of RM were studied at 300 MPa and 10 °C. Compared with the control, protein and lipase activities were reduced at HHPLT in RM. The L-values (luminance) of LHPLT applied RM were significantly (P < 0.05) decreased for colour Pressure application at 300 MPa for 90 min totally inactivated L. innocua at –20 °C in both RS and RM. L. innocua showed resistance to low pressure (200 MPa) in RM. Overall, increasing the pressure with applications at –20 and –30 °C resulted in a higher (P < 0.05) inactivation of L. innocua than at 10 and 20 °C. HHPLT applications to frozen RM resulted in the retention of textural characteristics.

With a long tradition of brewing history, Chinese strong-flavour Baijiu (SFB) developed prosperously in the southwest, especially in Luzhou, and has existed for more than 300 years building craftwork and brewing techniques. As a product of the distillation of fermented grains, its production involves many microbial communities. During this time, microbial communities within production have burgeoned and evolved throughout the development history, enhancing unique texture and flavour. Meanwhile, environmental factors are critical constituents in the production, which provide the optimal conditions for processing procedures and various microorganisms, including externally controlled macro-environment and micro-environment of fermentation. By studying the correlation with environmental factors from macro and micro perspectives, we illustrated the bond with environmental symbiotic and holistic patterns of the intrinsic microbial community and fermentation characteristics. This review is essential to study and control the whole ecological conditions of the Baijiu fermentation process, aiming to gain insight into the dynamics of the microorganisms and ensure a traditional fermentation environment for quality control.

The purpose of this paper is to evaluate current nutritional guidelines of modern diets based on medical and nutrition facts and their effect on gut microbiota and health, considering current recommendations of world authorities such as FAO and WHO. For this purpose, the first part is devoted to the impact of microbiota on human health, and special attention is committed to the effect of fibre on gut microbiota. The second part is dedicated to the fundamental division of diets and the evaluation of concrete nutritional guidelines of modern diets into microbiota and health, followed by the recommendations of global authorities. Modern diets include diets from the point of view of medical science (e.g. Mediterranean), promoted by nutritionists and authorities (e.g. Nordic) and by social trends (e.g. vegan). The evaluation summarises that high-fibre diets have tremendous benefits on human health. Diets with fresh, local and naturally fermented food positively impact the gut microbiota, hence human health (agrarian diets). The results of the review show that the nutritional guidelines associated with the lowest mortality are the Mediterranean with the Atlantic or Nordic diet, which is in line with the recommendation of the world authorities (FAO, WHO, UN). The low-fibre western diet with highly processed foods with no or very low levels of live bacteria appears to be high-risk in terms of preventing civilisation diseases with a negative impact on gut microbiota, which is in line with current FAO and WHO guidelines.

The objective of this study was to quantify the concentration of acrylamide in biscuits, bread, and cake obtained from industrial and local bakeries, classified based on their colour intensity as light, medium, or dark. The analysis was performed using gas chromatography-mass spectrometry (GC-MS). Sugar, moisture, and asparagine analyses were also carried out simultaneously. The results demonstrated that the acrylamide content in biscuits, bread, and cakes varied according to the colour (light 109.9 ± 7.95, 214.7 ± 27.40, and 128.6 ± 7.05; medium 176.3 ± 15.16, 387.0 ± 87.71, and 804.3 ± 17.16; and dark 407.6 ± 105.13, 555.8 ± 16.20, and 1 015.0 ± 83.68 µg·kg^–1, respectively). Statistically, significant differences were observed between acrylamide content and product colour density (P < 0.05). It can be concluded that the acrylamide content increases as the product colour intensity rises due to the increased baking temperature at which the reaction between reducing sugars and asparagine takes place, resulting in the formation of acrylamide. The results suggest that selecting commercial bakery products based on colour may be beneficial for reducing the daily intake of acrylamide by consumers. Therefore, it is recommended to avoid dark-coloured bakery products.

Mulberry is gaining attention for its potential health benefits. However, post-harvest deterioration of quality necessitates drying to prolong storage. This study aimed to investigate the effects of natural drying (ND), hot air drying (HAD), and vacuum freeze drying (VFD) on bioactive compounds and volatile organic compounds of fresh mulberries. The results showed that VFD had the highest retention of total phenols (5 553.87 ± 744.97 µg GAE·g^–1), total flavonoids (3 575.51 ± 465.98 µg rutin·g^–1), and total anthocyanins (64.98 ± 13.15 µg C3C·g^–1) after prolonged drying. Additionally, flavour was identified as the most important indicator influencing consumer preference for dried mulberries, and VFD was found to be effective in retaining the natural flavours of mulberries. Although thermal treatment leads to a significant loss of organic compounds, HAD showed good retention of active substances and lower energy consumption in a shorter processing time.

Diarrheagenic Escherichia coli (DEC) is a common pathogen around the world that can cause disease with symptoms of diarrhoea. We collected all clinical DEC isolates from diarrhoea samples in three sentinel hospitals for active surveillance of foodborne diseases in Huzhou, China, between 2020 and 2022. The isolates were characterised according to demographic characteristics, time distribution, distribution of suspected culprit foods, antimicrobial results of susceptibility testing, analysis of virulence genes, and pulsed-field gel electrophoresis (PFGE) typing. The positive detection rate was 7.28%, the highest for enteroaggregative E. coli (EAEC) strains, followed by enterotoxic E. coli (ETEC) strains. The predominant virulence genes were astA/pic in EAEC (57.25%) and estIa/estIb in ETEC (17.94%) strains. The proportion of cases was relatively high in children aged 6 years old (15.27%), and the peak of incidence was between June and September. The rates of drug resistance in DEC were high in Huzhou, and the spectrum of drug resistance was wide. The highest rate of drug resistance was for AMP (63.51%), and multiple drug resistance was common. The household was the leading site of DEC infection, and meat and meat products were the main suspected culprit foods (18.15%). EAEC strains showed 52.4–100.00% sequence identity, and ETEC strains showed 52.2–100.00% sequence identity. All cases of DEC infection in Huzhou were sporadic between 2020 and 2022. Strengthening continuous surveillance will be useful in the risk assessment of foodborne diseases caused by DEC.

The shelf life of a food product is a finite period after manufacturing and packaging, during which it retains a required and acceptable level of quality for consumption. The objective was to characterise and describe the transparent and comprehensible processing process to collect, select, critically evaluate and summarise available evidence regarding the use of mathematical models in the estimation of the shelf life of coffee under accelerated storage conditions. Of the 183 articles identified, nine studies were included in the review: four evaluated various types of packaging containing roasted and ground coffee, three coffee-based beverages, one infusion and one in bean format; the models frequently used were Weibull-Hazard Analysis, first-order, and zero-order kinetic model, which requires the decay kinetic constant, the same as that acquired by the Arrhenius model or a proposed model. Quality descriptors and mathematical models have been identified that allow estimating the shelf life of coffee and its derivative products under accelerated storage conditions, in addition to primary sources with experimental designs.

Triticale (× Triticosecale Wittmack) is a hybrid cereal prepared by crossing wheat and rye. Triticale grain contains substances that have a positive effect on reducing the risk of cardiovascular disease, obesity, cancer, and type 2 diabetes, as well as increasing body's immune response and intestinal function, which warrants a need for greater attention to research on triticale crop's nutritional composition. This review covers the most recent research on the nutritional composition of triticale grain in comparison to other cereals, its role in the food industry, and its usage as a food, providing a scientific foundation for triticale's further development as a sustainable crop. Due to the wide variety of chemical compounds revealed in triticale grain, it has the potential to be utilised as a substitute cereal for various food and beverages.

This study was conducted to evaluate the sufficiency of food safety practices in a catering company. The presence of some pathogenic and indicator bacteria was monitored in the samples collected from raw materials, food, food contact surfaces and workers' hands and various steps of the tas kebab (a Turkish meat stew) and salad processing lines. Bacillus cereus was found in ready-to-eat (RTE) tas kebab and RTE salad, while Listeria monocytogenes was isolated from RTE salad. Furthermore, it was observed that RTE salad contained coagulase-positive Staphylococcus aureus without staphylococcal enterotoxin production. The swab samples obtained from cutting board surfaces, knives and workers' hands contained high counts of total aerobic bacteria and some samples were contaminated with coliforms and coagulase-positive/negative staphylococci. The presence of B. cereus and L. monocytogenes in RTE foods is a serious threat to public health, especially in the catering business. Preventing the presence of toxin-producing bacteria in RTE food is a fundamental action. Also, the occurrence of L. monocytogenes in RTE salad and B. cereus in RTE tas kebab/salad samples showed insufficient cleaning/disinfection practices. As a result, hygiene practices and regular monitoring in the catering business are necessary for food safety.

Corrigendum in: CJFS. 2023 Feb 27; 41(1):78. doi:10.17221/26/2023-CJFS

Growing consumer awareness is forcing food producers to supply raw material and products of increasingly high quality and health-promoting properties. Knowledge of the genetic background of quality characteristics is taking on great importance, enabling selection based on molecular markers. The increasing throughput of molecular techniques, in combination with an expanding bioinformatics infrastructure, is leading to continual improvement in understanding of the molecular mechanisms influencing meat quality. This has resulted in the identification of polymorphic nucleotides [single nucleotide polymorphisms (SNPs)] showing a relationship with meat characteristics such as tenderness [polymorphism in the calpain (CAPN) and calpastatin (CAST) genes], marbling [diacylglycerol o-acyltransferase 1 (DGAT1)], colour, pH and water-holding capacity (WHC) [CAST, stearoyl-CoA desaturase (SCD) and others], and fatty acid profile (SCD1). An increasingly wide range of methods is used for analysis, from techniques based on amplification of nucleic acids [polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and amplification refractory mutation system-PCR (ARMS-PCR)] through Sanger sequencing to high-throughput next-generation sequencing (NGS) techniques. This paper is a review of the literature on polymorphism of genes determining the quality characteristics of meat and molecular methods used to detect them.

This study investigated the effects of some sweeteners (sucrose, honey and stevia) on the quality and thermal properties of plain (P) and cocoa (C) yogurt ice cream. For this purpose, six different yogurt ice cream samples were prepared with sucrose (control: AP, AC), with honey (BP, BC) and with stevia (CP, CC). The highest values of protein, ash, fat, lactose ratios and lightness (L*) were measured in samples with stevia. The addition of honey increased the b* values. The addition of cocoa increased pH and viscosity, but decreased overrun ratios. Although the addition of stevia reduced the lactic acid bacteria (LAB) counts, in all samples the LAB count was above 6 log CFU/g during storage. Results of the thermal and melting analysis showed that the use of stevia had a positive effect on the ice cream stability by increasing the freezing and melting point peak temperatures (Tf, Tm), the enthalpy (ΔHf, ΔHm), and the initial ice crystal melting temperatures (T'm).

Marine shellfish toxins are seafood safety problems of global concern. Herein the analysis of six shellfish toxins, regulated by European Union, with one single run by LC-MS/MS with acidic mobile phase was developed. After 80% methanol extraction of the shellfish toxins, the crude extract was subjected to HLB SPE cleanup before LC-MS/MS analysis. The method was validated according to Commission Decision 2002/657/EC. For azaspiracid-1 (AZA1), domoic acid (DA), dinophysistoxin-1 (DTX1), okadaic acid (OA), pectenotoxin-2 (PTX2), and yessotoxin (YTX) toxins the recovery rate was 99.4, 92.7, 114.1, 90.2, 115.2 and 87.8%, respectively. The intra-day relative standard deviation (RSD) was less than 5% for all of the shellfish toxins except DA. The inter-day RSD was less than 5% for AZA1, DTX1, PTX2, YTX, 7.85% for DA, and 14.63% for OA. The decision limit (CC_α) and detection capability (CC_β) for AZA1 were 13.6 and 14.8 ppb; for DA they were 1883 and 2051 ppb; DTX1 12.3 and 13.4 ppb; OA 8.0 and 8.7 ppb; PTX2 12.1 and 13.2 ppb; YTX 36.9 and 40.1 ppb.

The aim of the paper is to identify the factors influencing consumers when beer consumption and when choosing restaurants for beer consumption in the Czech Republic (CR). A partial goal was to compare preferences and factors influencing beer consumers from the Vysočina Region and the South-Moravian Region. The survey included a questionnaire survey, which 408 respondents took part in. The results showed that the most influential factors in the selection of beer for consumers are taste, a high-quality brand, and Czech production. Surprisingly, price was not found to be an influential factor in beer selection but is rather neutral. Factors that influence consumers most when choosing a restaurant for beer consumption were also identified. Consumers are most influenced by the quality of the beer on offer and the environment in which it is consumed.

DNA extraction is a crucial step in PCR analysis especially when analysing food samples that can be degraded and can potentially contain PCR-inhibiting substances. In this study, we compared the suitability of three DNA extraction methods - two kits: DNeasy^® Plant Mini Kit and NucleoSpin^® Food, and the CTAB method - for DNA extraction from commercial fruit jams. Fourteen jams with different contents of fruit, sugar and other additives were extracted in triplicate using the above-mentioned methods directly and after a washing step. The concentration and optical density were analysed using UV spectrophotometry and the amplifiability of the obtained DNA was evaluated using a PCR assay targeting a sequence coding for chloroplast tRNA-Leu. Samples isolated using the NucleoSpin^® Food kit contained non-amplifiable DNA in eight cases, and samples isolated using the CTAB method could not be quantified. The DNeasy^® Plant Mini Kit thus proved to be the most suitable method, since well-amplifiable DNA was obtained for all the analysed samples.

Hepatitis A and E viruses (HAV and HEV) are recognised as food- and water-borne infections and shellfish are a well-documented source of these viruses. The presence of HAV and HEV in mussels has not previously been investigated in Bosphorus, Istanbul, Turkey, and therefore the aim of this study was to investigate the frequency of HAV and HEV in mussels collected from this location. A total of 92 pooled samples representing 736 mussels originating along the Bosphorus coast were collected from fish distributors. RNA was extracted using the RNeasy Plant Mini Kit and a TaqMan real-time RT-PCR was performed using primers specific to HAV and HEV. Amongst the 92 pooled samples tested, 3 (3.3%) were found to be positive for HAV by the TaqMan real-time RT-PCR. No HEV was detected in any of the mussels tested. A 174 bp product was observed on gel electrophoresis with HAV positive samples detected by SYBR Green real-time PCR after reverse transcription. This product was sequenced and confirmed to contain HAV sequences by alignment using the data in GenBank. This is the first report describing the presence of HAV in mussels harvested in the Bosphorus, Istanbul, Turkey, indicating the potential contamination of aquatic environment and risk to public health.

In this paper are presented the findings obtained during the start-up of a freeze concentration pilot plant, that operated with suspension crystallisation and with simulated fruit juices. Solutions with different initial concentrations were tested, with and without acidification, to simulate fruit characteristics and behaviour. The experimental runs demonstrated that solution acidity has negligible effects on the process performance, whereas the results showed that the initial solution concentration influences the start-up duration. During this time, the solution concentration grows by about 10 °Brix, and the maximum quantity of ice content inside the crystalliser is always lower than 40% by weight. These findings can help to predict the performance of a freeze concentration plant and may facilitate achieving target concentrations in a more efficient mode. Taken together, the data suggest that the initial concentration of the processed juice influences start-up duration and the achievable final concentration.

The plate diffusion method is a reference method in the Czech Republic for determination of residues of antimicrobial agents in raw materials and foodstuffs of animal origin. A new method using the E. coli strain ATCC 11303 for the detection of fluoroquinolones was introduced in 2008. The aim of this study was to determine the detection capability (CCβ) of this modified method using this E. coli strain for selected fluoroquinolones registered in the Czech Republic for treating diseases in cattle - danofloxacin, marbofloxacin, ciprofloxacin, enrofloxacin, and flumequine. When comparing the maximum residue limits for individual fluoroquinolones and the CCβ values determined, we can state that the method displays very good sensitivity to ciprofloxacin and enrofloxacin (20 and 40 µg/l), marbofloxacin (70 µg/l), and danofloxacin (30 µg/l). The CCβ of the method for flumequine was not found in concentrations ≤ MRL. The method did not display sensitivity to flumequine even in a concentration equal to twelve times the MRL.

The technology of a functional fermented buttermilk-based beverage was developed and the impact of beverage consumption on the health parameters of young volunteers was studied. Three functional beverages were made on the basis of buttermilk, which differed in the composition. The beverage containing the buttermilk-skimmed milk-milk protein concentrate (0.3%) as a product with the preferred quality characteristics (synaeresis, viscosity, sensory properties, and acceptability) was used for further studies regarding the impact on human health. The medical nutrition experiments did not show any statistically significant effect on the biochemical blood parameters of 25 young volunteers after a 21-day period of the consumption of fermented buttermilk beverage with milk protein concentrate, although some of them (e.g. total, low- and high-density cholesterol, triacylglycerol concentrations, etc.) slightly decreased. The anthropometric and body composition, arterial blood pressure, and pulse evaluation indicators of recipients did not change significantly.

The aim of the study was to describe the distribution of total mercury in the tissues of fish originating from important Czech fishing locations and to determine the level of methylmercury as a percentage of total mercury (Hg speciation). At six important fishing locations a total of 144 fishes of 13 species were caught and analysed. Samples of muscle, liver, gonads and scales were analysed for total mercury and in the case of muscles for methylmercury concentrations. Total mercury was determined by AAS using an AMA 254 analyser, and methylmercury determination was performed by GC/ECD using a GC-2010A chromatograph. Total mercury concentrations in muscle and other tissues of all the fish from all fishing locations were below 0.5 mg/kg, with the exception of 6 asps (Aspius aspius). A significant (P < 0.05) correlation was found between the total mercury concentrations in scales and other tissues. Methylmercury made up about 46-100% of total mercury in muscle. The overall results confirmed the good hygienic quality of fish from important Czech fishing locations.