The Effect of Fruit and Berry Pomaces on the Growth Dynamics of Microorganisms and Sensory Properties of Marinated Rainbow Trout.

Plant pomaces in suitable forms (powders, extracts) can be used in foods of animal origin to increase the nutritional value and safety of these foods. In the present study, water extracts of apple, black currant, rhubarb and tomato pomaces were used in fish marinade solutions to evaluate their effect on the growth dynamics of microorganisms and the growth potential of Listeria monocytogenes by challenge testing. The results showed that mesophilic aerobic microorganisms, Pseudomonas spp., yeasts and moulds remained at acceptable levels throughout the predetermined storage period. The challenge test results showed that the overall growth potential of L. monocytogenes in all marinated rainbow trout samples remained at ≤0.5 log10 cfu/g during the study period, and none of the marinated fish samples supported the growth of L. monocytogenes. In addition, the effect of fruit and berry pomaces on the sensory properties of marinated rainbow trout samples was evaluated. The results revealed that it is possible to effectively use fruit and berry pomaces in marinated fish products, ensuring food safety, high microbiological quality, acceptable sensory characteristics and a sufficiently long shelf life of the products.

Retrospective Use of Whole-Genome Sequencing Expands the Multicountry Outbreak Cluster of Listeria monocytogenes ST1247.

Listeria monocytogenes sequence type 1247 clonal complex 8 caused a prolonged multicountry outbreak in five EU countries: Denmark, Estonia, Finland, France, and Sweden. A total of 22 disease cases were identified with onset of symptoms between July 2014 and February 2019. Five patients died due to, or with, the disease. The retrospective analysis of L. monocytogenes isolate VLTRLM2013 revealed the presence of an outbreak-related strain (cgMLST type L2-SL8-ST1247-CT4158) in ready-to-eat fish product more than a year prior to the first outbreak-related cases. Reference outbreak strain and VLTRLM2013 strain were compared using core genome and whole-genome multilocus sequence typing analyses. Genomic level differences of the persistent L. monocytogenes strains associated with a prolonged multicountry foodborne listeriosis outbreak are described. It was concluded that the persistent nature of the multicountry outbreak-related L. monocytogenes strain VLTRLM2013 together with stress island, virulence, and antibiotic resistance genes could potentially be the determining factors for the extensive and prolonged outbreak affecting five European Union countries. Our results support the systematic application of whole-genome sequencing in food and public health surveillance and further encourages its wide adoption.

Nitrite and nitrate content in meat products and estimated nitrite intake by the Estonian children.

Public interest in nitrate and nitrite content reduction in meat products has increased; therefore, the aim of the present study was to determine nitrate and nitrite levels in commercial meat products as the main source of added nitrites, and to estimate their dietary intake by children. The intake of nitrite from processed meat products and drinking water by Estonian children was estimated. Daily intake estimations were based on the food consumption data of the National Institute for Health Development. In addition, nitrite/nitrate concentrations of meat and processed meat products were measured using a liquid chromatographic method with UV detection. Mean nitrite intakes among 1087 studied children were 0.015 and 0.016 mg kg-1 b.w. day-1, respectively, among children aged 12-35 months and 3-10 years. Acceptable daily intake (ADI) of 0.07 mg nitrite kg-1 b.w. day-1 was exceeded in 3.1% of children, being more prevalent in the younger age group. Considering the consumption of processed meat and drinking water, mean nitrite intakes in the younger and the older age groups were, respectively, 21.9% and 22.9% of the ADI. Study results indicated that over a period of 10 years, children's dietary nitrite intake from processed meat products has declined, which is probably caused by changes in food preferences and decreased usage of nitrite in cured meat products by meat industries.

Acrylamide in commercial foods and intake by infants in Estonia.

Acrylamide is formed when certain foods with low moisture are prepared at above 120 ºC, especially those foods containing asparagine and reducing sugars such as glucose and fructose. Acrylamide is a probable carcinogen, and from animal evidence the margins of exposure indicate a concern for neoplastic effects. On a body weight basis infants´ acrylamide intakes are often higher than those of adults. The aim of the study was to determine acrylamide levels in different commercially-available foods and to assess dietary acrylamide intakes by infants. The acrylamide content in samples ranged widely, from

Phenogenotypic Characterization of Escherichia coli O157:H7 Strains Isolated from Cattle at Slaughter.

Shiga toxin-producing Escherichia coli (STEC) O157:H7 was isolated from 30 (4%) of 744 cattle hide swab samples collected at Estonian slaughterhouses within a 3-year monitoring program of zoonotic pathogens. The isolates were characterized by determining the presence of STEC main virulence factors, the antimicrobial resistance profiles, and the genetic relatedness by pulsed-field gel electrophoresis (PFGE). Thirteen strains carried the stx2 gene alone and 17 both the stx1 and stx2 genes. The most frequently detected stx subtype was stx2c, occurring alone (n = 12) or in combination with subtype stx1a (n = 13). All isolates harbored the intimin-coding eae gene and produced enterohemolysin. Twelve isolates (40%) showed resistance to at least one of the 14 antimicrobials and the isolates were predominantly resistant to streptomycin, sulfamethoxazole, and ampicillin. No extended-spectrum beta-lactamase-producing isolates were detected. PFGE characterization of the isolates showed an overall similarity higher than 75%, and four clusters based on 100% similarity were revealed.