Black pepper (Piper Nigrum L.) bacterial decontamination by sterilization and microwave treatments

Microbial number reduction in spices through various treatments represents a necessity considering possible changes which may occur during spices’ storage and application in food resulting in public health risk. The present study was conducted in order to examine the effects of sterilisation and microwave irradiation treatments on total mesophilic aerobic bacteria (TMAB) and bacterial spore content reduction in black pepper. Treatments applied were: sterilisation at 130 °C during 30, 60 and 90 min; and microwave irradiation at a power level of 600 W during 1.5, 3, and 5 min. Prolongation of the sterilisation treatment expressed positive influence on TMAB and bacterial spore reduction in black pepper. Compared to the sterilisation, microwave irradiation treatment exhibited better results in terms of black pepper decontamination. Maximal decontamination regarding TMAB and bacterial spore was achieved in black pepper samples treated with microwave irradiation during 3 min. The present results suggest that microwave irradiation could be applied in black pepper decontamination considering better effectiveness compared to the sterilisation treatment

Bleeding of Common Carp (Cyprinus carpio) Improves Sensory Quality of Fillets and Slows Oxidative and Microbiological Changes During Refrigerated Aerobic Storage

Uzgoj šarana (Cyprinus carpio) jedna je od najvećih i najbrže rastućih proizvodnih djelatnosti diljem svijeta. Međutim, šaran često nije prihvatljiv potrošačima zbog svoje karakteristične boje i mirisa. U ovom je radu ispitan učinak ispuštanja krvi šarana na kakvoću fileta. Dobiveni rezultati pokazuju da je ispuštanjem krvi zarezivanjem škrga učinkovito smanjen udjel hema, i to od (9,6±1,6) u šaranu kojemu nije ispuštena krv do (2.34±0.8) μmol/kg hemoglobina u šaranu kojemu je ispuštena krv. Osim toga, u filetu šarana kojemu je ispuštena krv smanjen je nastanak primarnih i sekundarnih produkata oksidacije lipida te rast mikroorganizama tijekom 12 dana aerobnog skladištenja u hladnjaku. Posljednjeg dana skladištenja, u usporedbi s filetom šarana kojemu nije ispuštena krv, u filetu šarana kojemu je ispuštena krv količina se lipidnih hidroksiperoksida smanjila s (88,9±4,2) na (62,1±2,9) μmol/kg kumen hidroperoksida, količina se reaktivnih spojeva tiobarbiturne kiseline smanjila s (4,2±0,5) na (2,6±0,4) μmol/kg malondialdehida, te se broj mezofilnih bakterija smanjio s (6,4±0,1) na (4,0±0,2) log CFU/g i psihrotrofnih bakterija s (6,2±0,3) na (4,2±0,2) log CFU/g. Sirovi filet iskrvarenog šarana bio je svjetlije boje (L* vrijednost), te smanjenog intenziteta crvene (a* vrijednost) i žute boje (b* vrijednost) od fileta neiskrvarenog šarana. Senzorska je analiza potvrdila bolju boju, miris te cjelokupnu prihvatljivost fileta šarana kojemu je ispuštena krv. Stoga je zaključeno da ispuštanje krvi šarana u procesu obrade fileta može poboljšati prihvatljivost kod potrošača te produljiti vrijeme skladištenja.Common carp (Cyprinus carpio) aquaculture is one of the most important and rapidly growing productions around the world. However, for consumers, carp is often not acceptable due to its distinctive colour and odour. In this study, we investigated the effects of bleeding of common carp on fillet quality. The obtained results show that carp bleeding by cutting the gill arches is an effective way of reducing the total haem content, which here decreased from (9.6±1.6) in unbled carp to (2.34±0.8) μmol/kg of haemoglobin in bled carp. Furthermore, fillets from bled carp showed reduced formation of primary and secondary lipid oxidation products and growth of microorganisms during 12 days of refrigerated aerobic storage. On the last day of storage, the amount of lipid hydroperoxides decreased from (88.9±4.2) in unbled to (62.1±2.9) μmol/kg of cumene hydroperoxide in bled carp, TBARS decreased from (4.2±0.5) in unbled to (2.6±0.4) μmol/kg of malondialdehyde in bled carp, mesophilic and psychrotrophic bacteria count decreased from (6.4±0.1) and (6.2±0.3) log CFU/g in unbled to (4.0±0.2) and (4.2±0.2) log CFU/g in bled carp, respectively. These raw bled fillets showed increased lightness L*, and reduced redness a* and yellowness b* compared to unbled fillets. Sensory analysis showed improved colour, odour and overall acceptability of bled raw fillets. Overall, bleeding improves the quality of carp fillets. Thus, inclusion of bleeding into processing of carp fillets has the potential to improve their acceptance by consumers and prolong their shelf-life

Black pepper (Piper nigrum L.) bacterial decontamination by sterilization and microwave treatments

Microbial number reduction in spices through various treatments represents a necessity considering possible changes which may occur during spices’ storage and application in food resulting in public health risk. The present study was conducted in order to examine the effects of sterilisation and microwave irradiation treatments on total mesophilic aerobic bacteria (TMAB) and bacterial spore content reduction in black pepper. Treatments applied were: sterilisation at 130 °C during 30, 60 and 90 min; and microwave irradiation at a power level of 600 W during 1.5, 3, and 5 min. Prolongation of the sterilisation treatment expressed positive influence on TMAB and bacterial spore reduction in black pepper. Compared to the sterilisation, microwave irradiation treatment exhibited better results in terms of black pepper decontamination. Maximal decontamination regarding TMAB and bacterial spore was achieved in black pepper samples treated with microwave irradiation during 3 min. The present results suggest that microwave irradiation could be applied in black pepper decontamination considering better effectiveness compared to the sterilisation treatment

Modulation of Campylobacter jejuni adhesion to biotic model surfaces by fungal lectins and protease inhibitors

Campylobacter jejuni, a Gram-negative bacterium, is one of the most common causes of foodborne illness worldwide. Its adhesion mechanism is mediated by several bacterial factors, including flagellum, protein adhesins, lipooligosaccharides, proteases, and host factors, such as surface glycans on epithelial cells and mucins. Fungal lectins, specialized carbohydrate-binding proteins, can bind to specific glycans on host and bacterial cells and thus influence pathogenesis. In this study, we investigated the effects of fungal lectins and protease inhibitors on the adhesion of C. jejuni to model biotic surfaces (mucin, fibronectin, and collagen) and Caco-2 cells as well as the invasion of Caco-2 cells. The lectins Marasmius oreades agglutinin (MOA) and Laccaria bicolor tectonin 2 (Tec2) showed remarkable efficacy in all experiments. In addition, different pre-incubations of lectins with C. jejuni or Caco-2 cells significantly inhibited the ability of C. jejuni to adhere to and invade Caco-2 cells, but to varying degrees. Pre-incubation of Caco-2 cells with selected lectins reduced the number of invasive C. jejuni cells the most, while simultaneous incubation showed the greatest reduction in adherent C. jejuni cells. These results suggest that fungal lectins are a promising tool for the prevention and treatment of C. jejuni infections. Furthermore, this study highlights the potential of fungi as a rich reservoir for novel anti-adhesive agents

Možnosti zmanjšanja mikrobiološke kontaminacije mesa navadnega krapa (Cyprinus carpio)

Common carp aquaculture is one of the most important in the world but only a small part of the production is tied to Europe, where carp is not yet fully exploited due to its sensory characteristics and despite its good nutritional value and economic accessibility. We have shown that bleeding as an additional processing step improves the carp meat quality with improved sensory characteristics and slowed down lipid oxidation and bacterial growth. Spoilage of fresh fish meat is defined by microbial activity, especially by representatives of the genus Pseudomonas. These are often resistant to antimicrobials, but we have demonstrated anti-Pseudomonas activity by inhibition of their growth and enzymatic activity by commercially available natural additives based on rosemary extract and buffered vinegar as well as ethanolic extracts of oregano and nettle. Pseudomonas are also found in biofilms on surfaces in fish processing. We show that Pseudomonas can easily adhere and form biofilm on stainless steel and polystyrene at 5 °C, 15 °C and 30 °C, but this was more pronounced on stainless steel. These Pseudomonas produced protease and lipase, and their activity increased with increasing temperature from 5 °C to 15 °C. Pseudomonas can thus form a biofilm in which they harbour bacterial cells and their spoilage enzymes. Fish meat can therefore easily be contaminated from surfaces during processing. We further show that the transfer of Pseudomonas from a biofilm formed on stainless steel as a donor surface depends on the amount of lipids and proteins in the recipient surface. The dynamics from the first to the last succession contact showed that the higher the rate of decline, the faster the transfer rate decreases. But, if the rate is lower, the difference in transfer rates between successive contacts is smaller and could represent a longer lasting constant contamination of the food.Akvakultura navadnega krapa je ena izmed najpomembnejših na svetu, a le majhen del proizvodnje je vezan na Evropo, kjer krap zaradi svojih senzoričnih lastnosti – kljub dobri hranilni vrednosti in cenovni dostopnosti – ostaja neizkoriščen. Pokazali smo, da dodatni procesni korak izkrvavitve izboljša kakovost mesa navadnega krapa z zavrtjem oksidacije maščob in rasti bakterij, kar izboljša senzorične lastnosti in upočasni kvar. Kvar svežega mesa rib povzročijo predvsem bakterije, med njimi prevladujejo vrste rodu Pseudomonas. Te bakterije so pogosto odporne proti protimikrobnim snovem, a smo pokazali dobro proti-Pseudomonas aktivnost komercialnih naravnih dodatkov na osnovi izvlečka rožmarina in puferiranega kisa ter pripravljenih etanolnih izvlečkov origana in koprive. V sprejemljivih koncentracijah so zavrli rast bakterij in njihovo encimsko aktivnost. Bakterije Pseudomonas najdemo tudi v biofilmih na površinah v obratih predelave mesa rib. Pokazali smo, da se bakterije Pseudomonas adherirajo in tvorijo biofilm na nerjavnem jeklu in polistirenu pri 5 °C, 15 °C in 30 °C. Bakterije Pseudomonas lahko tvorijo biofilm na površinah materialov, ki se uporabljajo v predelovalni industriji rib, v njem so bakterijske celice in encimi kvara. Meso rib se lahko dodatno kontaminira med predelavo, kar smo preučili v nadaljevanju raziskave. Pokazali smo, da je prenos bakterij Pseudomonas s površinsko tvorjenega biofima na nerjavnem jeklu odvisen od količine beljakovin in maščob modelne kontaktne površine. Dinamika od prvega do zadnjega zaporednega kontakta je pokazala, da čim višja je hitrost padanja prenosa biofilmskih celic, hitreje se prenos zniža. A če je hitrost manjša, je razlika v stopnji prenosa med zaporednimi stiki manjša in lahko predstavlja dolgotrajnejšo kontaminacijo

La carpa - todavia potencial aún sin explotar

Carps are the most cultured fish worldwide. Their production is still increasing. Common carp is the third most produced fish species, but in year 2014 only 2.32% of the total was produced in Europe. Together with trout aquaculture, the production of carp in Europe is the most important one. The majority is tied to aquaculture, only about 10% is captured. Carp market relies mainly on domestic production. However, trade between countries is still traditionally based on live fish, only a small part presents fresh chilled and frozen fish. In the lowlands without access to the sea, but with a possibility of aquaculture production in ponds, carps represent a good potential as a nutrient source for the local population throughout the year. Consumption of carps is primarily local where the market offers variety of carp meat products. Carp, like other fish, has good nutritional value, with quality and nutritional animal proteins and lipids as well as micronutriens. Despite the favorable content of valuable nutrients, freshwater fish are often overlooked as their source, so there is still space for improvement by transferring more knowledge to the consumers and developing new attractive and innovative products. As an example of good practice, an omega-3 carp trademark is mentioned. It was developed in Czech Republic on the basis of traditional common carp production, but offering consumers a new value-added productŠaran je jedna od najkultiviranijih riba u cijelom svijetu, a njegova proizvodnja stalno raste. Slatkovodna riba važan je izvor hrane u zemljama u razvoju, no u razvijenim zemljama riba se često smatra skupom delikatesom. Ne samo da je riba izvrsna i kvalitetna hranjiva namirnica (bjelančevine, lipidi, mikronutrijenti), ona uključuje i važne bioaktivne sastojke s blagotvornim učinkom na ljudsko zdravlje, od čega posebno n-3 višestruko nezasićene masne kiseline (PUFA) igraju važnu ulogu u sprečavanju kardiovaskularnih bolesti. Unatoč visokom sadržaju tih vrijednih nutrijenata, slatkovodna riba često je zanemarena kao njihov izvor. Međutim, proteklih godina i slatkovodna riba polako dobiva na važnosti kao hrana n-3 PUFA izvora. Tijekom proteklih godina, šaran je ispitivan s obzirom na mogući zaštitni učinak na srce, te je dokazano da meso šarana ima važne pozitivne učinke u prevenciji kardiovaskularnih bolesti i potrebno ga je priznati i promovirati kao zdravu hranu. Kako bi se mogli isporučiti proizvodi od šarana najviše moguće kvalitete, potrebno je na tom području provesti više istraživanja i inovacija radi poboljšanja cjelokupnog lanca proizvodnje od ribnjaka do tanjura.Der Karpfen gehört zu den kultiviertesten Fischarten weltweit; seine Produktion steigt kontinuierlich an. Der Süßwasserfisch stellt eine bedeutende Nahrungsquelle in den Entwicklungsländern dar; in den entwickelten Ländern wird er aber häufig für eine teuere Delikatesse gehalten. Der Fisch ist nicht nur ein hervorragendes und äußerst nahrhaftes Nahrungsmittel (Eiweiße, Lipide, Mikronährstoffe), er enthält zudem wichtige bioaktive Inhaltsstoffe mit einer wohltuenden Wirkung auf die menschliche Gesundheit; dabei spielen insbesondere die n-3 mehrfach ungesättigten Fettsäuren (PUFA) eine bedeutende Rolle bei der Vorbeugung von Herz-Gefäßkrankheiten. Trotz dem hohen Gehalt an wertvollen Nährstoffen wird der Süßwasserfisch als eine bedeutende Nährstoffquelle sehr häufig vernachlässigt. Seit einigen Jahren kommt dem Süßwasserfisch als einer Quelle von n-3 mehrfach ungesättigten Fettsäuren eine immer größere Bedeutung zu. In den letzten Jahren wurde die mögliche Schutzwirkung des Karpfens auf das Herz untersucht; dabei konnte nachgewiesen werden, dass das Karpfenfleisch zahlreiche positive Auswirkungen bei der Vorbeugung von Herz-Gefäßkrankheiten hat und es als gesunde Nahrung anerkannt und gefördert werden sollte. Um Karpfenprodukte mit bestmöglicher Qualität liefern zu können, bedarf es zahlreicher Untersuchungen und Innovationen zur Verbesserung der kompletten Produktionskette vom Fischteich bis zum Teller.L’allevamento della carpa è tra i più diffusi al mondo e la sua produzione è in costante aumento. Il pesce d’acqua dolce è un’importante fonte alimentare nei paesi in via di sviluppo; tuttavia, nei paesi più sviluppati, il pesce è spesso considerato, per il suo prezzo a volte proibitivo, un alimento per pochi. Il pesce non è soltanto un alimento straordinariamente nutriente (proteine, lipidi, micronutrienti): esso contiene anche importanti componenti bioattivi che svolgono un effetto benefico sulla salute umana, come, ad esempio, gli acidi grassi polinsaturi omega 3 (PUFA) che giocano un ruolo molto importante nella prevenzione delle malattie cardiovascolari. Malgrado siano ricchi di questi importanti nutrienti, i pesci d’acqua dolce spesso non sono sufficientemente apprezzati come loro fonte. Negli ultimi anni, tuttavia, anche i pesci d’acqua dolce sono riconosciuti come alimento ricco di acidi grassi polinsaturi omega 3. Negli ultimi anni, la carpa è stata sottoposta a prove di laboratorio finalizzate a provarne gli effetti protettivi sul cuore; è stato così accertato che la carne della carpa svolge una funzione molto importante nella prevenzione delle malattie cardiovascolari e che va, quindi, riconosciuta e promossa come cibo salutare. Affinché la produzione ittica legata alla carpa sia della migliore qualità possibile, è necessario intensificare le ricerche e l’innovazione in questo settore al fine di migliorare l’intera catena produttiva dalla peschiera al piatto.La carpa es uno de los peces más cultivados del mundo, y su producción está creciendo constantemente. Los peces de agua dulce son una fuente importante de alimentos en los países en desarrollo, pero en los países desarrollados, el pescado se considera a menudo un manjar caro. Aparte de ser una excelente comida nutritiva de calidad (proteínas, lípidos, micronutrientes), incluye importantes ingredientes bioactivos que tienen un efecto beneficioso sobre la salud humana, de los cuales en especial los ácidos grasos poliinsaturados (PUFA) n-3 que tienen un papel importante en la prevención de enfermedades cardiovasculares. A pesar del alto contenido de estos valiosos nutrientes, los peces de agua dulce son a menudo descuidados como fuente de nutrientes. Sin embargo, en los años recientes los peces de agua dulce están adquiriendo importancia lentamente como alimentos fuente de PUFA n-3. En los últimos años, la carpa fue examinada con respecto al posible efecto protector sobre el corazón, y se ha demostrado que la carne de carpa tiene importantes efectos positivos en la prevención de enfermedades cardiovasculares y necesita ser reconocido y promovido como alimento saludable. Con el fin de ser capaces de ofrecer productos de carpa de la calidad más alta posible, es necesario en este área llevar a cabo más estudios e introducir innovaciones para mejorar toda la cadena de producción de la granja de peces hasta que llegan al plato

A novel approach using growth curve analysis to distinguish between antimicrobial and anti-biofilm activities against Salmonella

Salmonella spp. are a commonly identified cause of outbreaks of food-borne diseases. Despite much research, there remains the need to find new antimicrobial and anti-biofilm agents against Salmonella. For this, it is necessary to distinguish between these two aspects. Agents that influence biofilm formation should not affect bacterial growth, to thus avoid further promotion of the development of resistance. In this study, we present the use of growth curves of Salmonella Infantis to simultaneously determine antimicrobial and anti-biofilm activities, for the screening for anti-Salmonella activities of 42 aqueous fungal extracts. The extract from Pseudohydnum gelatinosum showed good antimicrobial activity, and that from Pleurotus ostreatus showed good anti-biofilm activity. In extracts from Infundibulicybe geotropa and Infundibulicybe gibba, both activities were determined after fractionation. The antimicrobial activity was associated with protein-rich fractions and mediated by L-amino acid oxidase activity. The fractionation did not allow determination of the anti-biofilm active fraction, so further studies are needed to define these compounds. Growth curve analysis of S. Infantis is shown here to provide a fast and simple approach to distinguish between antimicrobial and anti-biofilm activities in a high-throughput setting, such that it can be easily implemented in screening and further bioassay-based purification of novel alternatives to antibiotics

Beyond Birth: Pioneering Insights into Colostrum Quality Variation among Bitches with Different Types of Parturition

This study deals with the immunological quality of canine colostrum in relation to the different parturition modes in bitches. It included four groups of bitches, who underwent vaginal parturition (VP), emergency cesarean section (EM-CS), elective cesarean section (EL-CS), or elective cesarean section with aglepristone injection 24 h prior to surgery (EL-A). Colostrum samples from 40 bitches of 18 breeds were taken immediately after the birth of the first puppy or directly after surgery, and four hours later. The concentrations of immunoglobulin G (IgG) and IgA were measured using ELISA tests. The initial IgG concentration was 18.3 ± 10.2 g/L, and the IgA concentration was 13.7 ± 5.8 g/L, respectively. Significantly lower IgG and IgA concentrations were observed in the EL-CS group compared to other groups. The administration of aglepristone led to an increase in IgG and IgA concentrations. Despite the lower immunoglobulin levels with EL-CS, the survival rate of the puppies was not affected. The study shows that immunoglobulin concentrations in colostrum vary between bitches, with the type of birth significantly influencing the levels. Progesterone withdrawal before birth could play a decisive role in increasing IgG and IgA concentrations in the mammary glands of the bitches