Development of a novel smoke-flavoured salmon product by sodium replacement using water vapour permeable bags

This is the peer reviewed version of the following article: Rizo Parraga, Arancha Maria, Fuentes López, Ana, Barat Baviera, José Manuel, Fernández Segovia, Isabel. (2018). Development of a novel smoke-flavoured salmon product by sodium replacement using water vapour permeable bags.Journal of the Science of Food and Agriculture, 98, 7, 2721-2728. DOI: 10.1002/jsfa.8767, which has been published in final form at http://doi.org/ 10.1002/jsfa.8767. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] BACKGROUND: Food manufacturers need to reduce sodium contents to meet consumer and public health demands. In this study the use of sodium-free (SF) salt and KCl to develop a novel smoke-flavoured salmon product with reduced sodium content was evaluated. Fifty percent of NaCl was replaced with 50% of SF salt or 50% KCl in the salmon smoke-flavouring process carried out using water vapour permeable bags. RESULTS: Triangle tests showed that samples with either SF salt or KCl were statistically similar to the control samples (100% NaCl). Since no sensorial advantage in using SF salt was found compared with KCl and given the lower price of KCl, the KCl-NaCl samples were selected for the next phase. The changes of physicochemical and microbial parameters in smoke-flavoured salmon during 42 days showed that partial replacement of NaCl with KCl did not significantly affect the quality and shelf-life of smoke-flavoured salmon, which was over 42 days. CONCLUSION: Smoke-flavoured salmon with 37% sodium reduction was developed without affecting sensory features and shelf-life. This is an interesting option for reducing sodium content in such products to help meet the needs set by both health authorities and consumers.We gratefully acknowledge the support of Tub-Ex Aps (Taars, Denmark) for suppling the water vapour permeable bags and for providing all of the necessary technical information. Arantxa Rizo thanks the Universitat Politecnica de Valencia for the FPI grant.Rizo Parraga, AM.; Fuentes López, A.; Barat Baviera, JM.; Fernández Segovia, I. (2018). Development of a novel smoke-flavoured salmon product by sodium replacement using water vapour permeable bags. Journal of the Science of Food and Agriculture. 98(7):2721-2728. https://doi.org/10.1002/jsfa.8767S2721272898

The speciation and genotyping of Cronobacter isolates from hospitalised patients

The World Health Organization (WHO) has recognised all Cronobacter species as human pathogens. Among premature neonates and immunocompromised infants, these infections can be life-threatening, with clinical presentations of septicaemia, meningitis and necrotising enterocolitis. The neurological sequelae can be permanent and the mortality rate as high as 40 – 80 %. Despite the highlighted issues of neonatal infections, the majority of Cronobacter infections are in the elderly population suffering from serious underlying disease or malignancy and include wound and urinary tract infections, osteomyelitis, bacteraemia and septicaemia. However, no age profiling studies have speciated or genotyped the Cronobacter isolates. A clinical collection of 51 Cronobacter strains from two hospitals were speciated and genotyped using 7-loci multilocus sequence typing (MLST), rpoB gene sequence analysis, O-antigen typing and pulsed- field gel electrophoresis (PFGE). The isolates were predominated by C. sakazakii sequence type 4 (63 %, 32/51) and C. malonaticus sequence type 7 (33 %, 17/51). These had been isolated from throat and sputum samples of all age groups, as well as recal and faecal swabs. There was no apparent relatedness between the age of the patient and the Cronobacter species isolated. Despite the high clonality of Cronobacter , PFGE profiles differentiated strains across the sequence types into 15 pulsotypes. There was almost complete agreement between O-antigen typing and rpoB gene sequence analysis and MLST profiling. This study shows the value of applying MLST to bacterial population studies with strains from two patient cohorts, combined with PFGE for further discrimination of strains

Postharvest quality of refrigerated tomato fruit (Solanum lycopersicum, cv. Zinac) at two maturity stages following heat treatment

This study evaluated the effect of water heat treatment (WHT, immersion in a water bath at 40C - 30 min) application in alternative to the conventional decontamination treatment of chlorinated water (150 ppm at 5C, pH 6.5 during 2 min) on tomato (cv. Zinac) at two maturity stages (turning and pink). Physiochemical attributes, enzymatic activities and microbial load were evaluated after treatments and during 14 days of storage at 10C. The WHT applied was very effective on microbial reduction and delayed physiochemical changes of tomato, namely firmness loss and red color development during storage period, especially at turning maturity stage. Based on the firmness parameter, shelf-life of control and WHT samples were determined. Our results provide strong evidence that postharvest WHT (40C - 30 min) for tomato fruits at turning maturity stage guarantees the overall quality at 10C twice as long of fruits washed with chlorinated water.info:eu-repo/semantics/acceptedVersio

Predictive models for bacterial growth in sea bass (Dicentrarchus labrax) 1 stored on ice

The final publication is available at Springer."The purpose of this paper was to estimate microbial growth through predictive modelling as a key element in determining the quantitative microbiological contamination of sea bass stored on ice and cultivated in different seasons of the year. In the present study, two different statistical models were used to analyse changes in microbial growth in whole, ungutted sea bass (Dicentrarchus labrax) stored on ice. The total counts of aerobic mesophilic and psychrotrophic bacteria, Pseudomonas sp., Aeromonas sp., Shewanella putrefaciens, Enterobacteriaceae, sulphide-reducing Clostridium and Photobacterium phosphoreum were determined in muscle, skin and gills over an 18-day period using traditional methods and evaluating the seasonal effect. The results showed that specific spoilage bacteria (SSB) were dominant in all tissues analysed but were mainly found in the gills. Predictive modelling showed a seasonal effect among the fish analysed. The application of these models can contribute to the improvement of food safety control by improving knowledge of the microorganisms responsible for the spoilage and deterioration of sea bass.