BackgroundCampylobacteriosis is a zoonotic disease, and animals such as poultry, pigs and cattle may act as reservoirs for Campylobacter spp. Cattle shed Campylobacter spp. into the environment and they can act as a reservoir for human infection directly via contact with cattle or their faeces or indirectly by consumption of contaminated food. The aim of this study was to determine the prevalence, the quantitative load and the genetic strain diversity of Campylobacter spp. in dairy cattle of different age groups.ResultsFaecal samples of 200 dairy cattle from three farms in the central part of Lithuania were collected and examined for Campylobacter. Cattle herds of all three farms were Campylobacter spp. positive, with a prevalence ranging from 75% (farm I), 77.5% (farm II) to 83.3% (farm III). Overall, the highest prevalence was detected in calves (86.5%) and heifers (86.2%). In contrast, the lowest Campylobacter prevalence was detectable in dairy cows (60.6%). C. jejuni, C. coli, C. lari and C. fetus subsp. fetus were identified in faecal samples of dairy cattle. C. upsaliensis was not detectable in any sample. The high counts of Campylobacter spp. were observed in faecal material of dairy cattle (average 4.5 log10 cfu/g). The highest numbers of Campylobacter spp. were found in faecal samples from calves (average 5.3 log10 cfu/g), whereas, faecal samples from cows harboured the lowest number of Campylobacter spp. (average 3.7 log10 cfu/g). Genotyping by flaA PCR-RFLP analysis of selected C. jejuni isolates showed that some genotypes were present in all farms and all age groups. However, farm or age specific genotypes were also identified.ConclusionsFuture studies are needed to investigate risk factors related to the degree of colonisation in cattle. Based on that, possible measures to reduce the colonisation and subsequent shedding of Campylobacter in cattle could be established. It is important to further investigate the epidemiology of Campylobacter in the cattle population in order to assess associated risks to public health.

The antimicrobial effect of spice-based marinades against Campylobacter jejuni on inoculated fresh broiler wings was investigated. Experiments were carried out with 1 strain of C. jejuni and 6 marinades. Four experimental marinades were composed for the study and contained spices (thyme, rosemary, basil, marjoram, and so on) and different combination of bioactive compounds. Two marinades were commercial and contained spices (black pepper, sweet red pepper, and so on) and chemical additives (monosodium glutamate, sodium diacetate, calcium lactate), 1 commercial marinade was also enriched with bioactive compounds (linalool, cinnamaldehyde, lactic acid). Total aerobic bacterial count was examined to estimate the possible effect of tested marinades on the shelf-life of marinated broiler wings. Study revealed that thyme-based marinade was the most effective against C. jejuni on broiler wings and reduced the numbers of campylobacters by 1.04 log colony forming unit (CFU)/g (P ≤ 0.05) during storage for 168 h at 4 °C temperature. Moreover, it was more effective against C. jejuni than commercial marinade with 0.47 log CFU/g (P ≤ 0.05) reduction effect. Both experimental and commercial marinades had very similar effect on the total aerobic bacterial count. Although experimental and commercial marinades had different effect on pH of broiler wings, this parameter did not show a major impact on the antimicrobial effect of tested marinades (P ≥ 0.05). Our study shows that experimental natural thyme-based marinade can reduce numbers of C. jejuni more effectively than tested commercial marinades.

The effect of taxifolin (TXF) with starter cultures (SC), such as Leuconostoc carnosum, or a mixture of  strains Pediococcus pentosaceus and Staphylococcus xylosus, on the TXF stability was evaluated. UPLC analysis demonstrated that after 181 days of storage total TXF content was the highest in samples with TXF and L. carnosum (60%), compared to the 1st day of storage. The sausages with TXF and the mixture of P. pentosaceus and S. xylosus (56%) followed next. The samples treated only with TXF retained 40% of TXF, compared to the 1st day of storage. TXF had no significant effect on the growth of lactic acid bacteria. The accumulation of biogenic amines (BA), including histamine and putrescine, was more effectively reduced in sausages inoculated with the TXF plus P. pentosaceus and S. xylosus mixture. Using this mixture, the rate of lipolysis and processes of lipid oxidation were effectively slowed down. Fatty acid (FA) composition was stable in all cases.

Rokaityte A., Zaborskiene G., Macioniene I., Rokaitis I., Sekmokiene D. (2016): Combined effect of lactic acid, bioactive components and modified atmosphere packaging on the quality of minced meat. Czech J. Food Sci., 34: 52-60.The quality of minced beef was improved. Combinations of modified atmosphere packaging (MAP) and vacuum packaging (VP) with lactic acid (LA), dihydroquercetin (DHQ) and linalool (LIN) mixes were used on fresh minced beef. In the course of the study the total aerobic bacterial, escherichia coli, yeast and mould counts and formation of biogenic amines during 9 days of storage at +4°C temperature were investigated. Mixtures of DHQ+LA+LIN and DHQ+LA solutions statistically significantly reduced the total aerobic bacterial and e. coli count and meat pH (P ≤ 0.05) in comparison with control samples. We have identified a strong positive correlation between pH and total aerobic bacterial (R = 0.736, P < 0.01) and e. coli count (R = 0.818, P < 0.01). Significant differences in the total biogenic amine content were determined between DHQ+LA+LIN and DHQ+LA treated samples in air packaging (AP) (P ≤ 0.05). However, there were no significant differences (P > 0.05) in the total aerobic bacterial and e. coli count between the different packaging techniques, but VP effectively inhibited yeasts and moulds in minced beef (P ≤ 0.05).

The aim of this work is to evaluate the effect of taxifolin on the physicochemical and microbiological properties of cold-smoked pork sausages produced using different commercial starter cultures with Leuconostoc carnosum and with a mixture of Pediococcus pentosaceus and Staphylococcus xylosus. Ultra performance liquid chromatography analysis demonstrated that after 181 days of storage total taxifolin content was the highest in samples with taxifolin and L. carnosum (60 %), compared to the first day of storage. The sausages with taxifolin and the mixture of P. pentosaceus and S. xylosus (56 %) followed next. Taxifolin improved the hygienic quality of sausages without significant effect on the growth of lactic acid bacteria. The accumulation of biogenic amines, including histamine and putrescine, was more effectively reduced in sausages inoculated with the taxifolin and P. pentosaceus and S. xylosus mixture. Using this mixture, the rate of lipolysis and lipid oxidation were effectively slowed down. Samples with taxifolin and L. carnosum showed the highest free radical scavenging activity on the first day of the study ((77.4±1.3) %) (p<0.05 in all samples). Mixtures containing taxifolin and starter cultures bound free radicals better than taxifolin alone. The colour parameters (L*, a* and b*) of preparations and final products were significantly influenced by taxifolin and starter cultures and storage time (p<0.05 in all samples).