Uporedna ispitivanja kvaliteta goveđe pršute proizvedene na tradicionalan i industrijski način

The paper studies the chemical quality and oxidative status of beef prosciutto produced by different processes: in industrial conditions and in the traditional manner. Slightly larger differences are determined in moisture, fat and NaCl content, but the ash, nitrogen and protein content, as well as the pH value is not significantly varied in the samples of prosciutto produced by various methods. The acid number of the sample industrially manufactured beef prosciutto was slightly lower than in the sample of beef prosciutto produced in the traditional manner. Slightly higher peroxide value for beef prosciutto produced in the traditional manner is the result of a stronger influence of prooxidative factors (air, light, moisture), which are significantly smaller extent affected the patterns of beef prosciutto produced industrially and packed in a vacuum.U radu je ispitivan hemijski kvalitet i oksidativni status goveđe pršute proizvedene različitim postupcima: u industrijskim uslovima i na tradicionalan način. Utvrđene su nešto malo veće razlike u sadržaju vlage, masti i NaCl, dok se sadržaj pepela, azota, proteina, kao i pH vrednost, nisu bitnije razlikovale u uzorcima pršute proizvedene različitim postupcima. Kiselinski broj uzorka industrijski proizvedene goveđe pršute je bio neznatno niži od kiselinskog broja goveđe pršute koja je proizvedena tradicionalnim postupkom. Nešto viši peroksidni broj goveđe pršute proizvedene na tradicionalan način rezultat je snažnijeg delovanja prooksidativnih faktora (vazduh, svetlost, vlaga), koji su u znatno manjem obimu uticali na uzorke goveđe pršute proizvedene na industrijski način, upakovane u vakuumu

Proizvodnja mikrobnih belančevina za potrebe ishrane domaćih životinja

In the paper it is presented the importance of alternative systems to solve the protein deficit in the diet of farm animals, using a variety of microorganisms as producers of protein grown on waste organic substrates. Indicates to the biotechnological specificity of the microbial conversion of organic substrates into the feed with a high protein content, as well as the selection of the biological producers and row materials, which are used for the production. An important part of this work refers to proteins enrichment of coarse plant material (with increased content of cellulose, lignocellulose, starch, etc.) by direct cultivation of microorganisms on them, in order to improve their quality and digestibility by the domestic animals.U radu je prikazan značaj alternativnih sistema rešavanja proteinskog deficita u ishrani domaćih životinja, korišćenjem različitih mikroorganizama kao producenata proteina gajenih na otpadnim organskim supstratima. Ukazuje se na biotehnološke specifičnosti mikrobiološke konverzije organskih supstrata u stočnu hranu sa visokim sadržajem belančevina kao i na odabir bioloških producenata i sirovina koje se koriste za tu proizvodnju. Bitan deo ovog rada se odnosi na proteinizaciju grubih biljnih materijala (sa povećenim sadržajem celuloze, lignoceluloze, skroba i sl.) direktnim gajenjem mikroorganizama na njima, a u cilju poboljšanja njihovog kvaliteta i svarljivosti od strane domaćih životinja

Effect of Modified Atmosphere Pakaging on the Shelf-life of Common Carp (Cyprinus carpio) Steaks

AbstractThe effect of modified atmosphere packaging (MAP 1: 40%CO2+60%N2 and MAP 2: 100%CO2) on the shelf-life of carp steaks was studied. Carp steaks were stored at +3±0.5˚C and on days 1, 3, 6, 9, 13 and 15, microbiological, chemical and sensory testing was performed. Based primarily on odour scores it was observed that carp steaks packaged in MAP1 remained acceptable up to 13 days of storage, while carp steaks packaged in MAP2 remained unchanged until the end of the study. By using MAP, especially 100% CO2, products shelf-life can be significantly prolonged

Uticaj funkcionalne smeše na bazi alginata na hemijski kvalitet i energijsku vrednost viršli

This study examines the impact of alginate based functional mixtures on chemical quality and reducing of the energy value of the hot dogs. Analyzing results of chemical quality can be concluded that the firm adipose tissue may replace with the emulsion mixtures based on alginate in quantities of 20 g/kg (experimental group 1) and 40 g/kg of emulsion-soft fat ice-water (experimental group 2). This exchange does not have a negative impact on the chemical composition of the sample hot dogs, which achieve significantly lower levels of fat, and reduced energy value. The energy value is decreased by the value determined in hot dogs of control group (1365.22 kJ/100g), experimental group 1 (1297.04 kJ/100g) and hot dogs of experimental group 2 (1289.09 kJ/100g).U radu je ispitivan uticaj funkcionalne smeše na bazi alginata na hemijski kvalitet i smanjenje energijske vrednosti viršli. Analizom rezultata ispitivanja hemijskog kvaliteta može se zaključiti da se čvrsto masno tkivo može zameniti emulzijom smeše na bazi alginata u količinama od 20 g/kg (ogledna grupa 1) i 40 g/kg emulzije-meko masno tkivo voda-led (ogledna grupa 2). Ova zamena nema negativan uticaj na hemijski sastav oglednih viršli, u kojima se postigao značajno niži nivo masti, i snizila energijska vrednost. Energijska vrednost je opadala od vrednosti utvrđenih u viršlama kontrolne grupe (1365.22 kJ/100g), ogledna grupa 1 (1297.04 kJ/100g) i viršle ogledne grupe 2 (1289.09 kJ/100g)

Utjecaj bakteriocina na kakvoću i sigurnost tradicionalno fermentiranih kobasica

Semi-purified bacteriocins produced by Lactobacillus sakei I154 (sakacin) and Leuconostoc mesenteroides E131 (leucocin) were implemented in the production of traditional Bosnian, Hungarian, Serbian and Croatian fermented sausages together with Listeria monocytogenes. Furthermore, leucocin and Lactobacillus sakei I151 were added to the sausages in order to investigate their influence to the natural microbial flora and physicochemical characteristics of traditional products. Leucocin possessed better antilisterial activity than sakacin. With addition of Lb. sakei I151 and leucocin the typical sensory characteristics of the traditional products remained recognizable, while the safety of sausages was improved due progressive elimination of undesirable microbial flora.PROŠIRENI SAŽETAK UVOD Otkako se bakterije mliječne kiseline koriste kao starterkulture, istraživanja su usmjerena na pronalaženje bakteriocinogenih sojeva. Među bakteriocinogenim bakterijama mliječne kiseline značajno mjesto zauzimaju vrste roda Lactobacillus, i to L. sakei (bakteriocin sakacin), L. Curvatus (curvacin), L. plantarum (plantaricin), L. Acidophilus (lactacin, acidocin) i L. bavaricus (bavaricin). Osim laktobacila bakteriocine stvaraju i Pediococcus spp. (bakteriocin pediocin), Leuconostoc spp. (leucocin), Enterococcus spp. (enterocin), Lactococcus spp. (lacticin, nizin), Carnobacterium spp. (carnocin). Cillj ovog rada bio je utvrditi učinkovitost bakteriocina soja Lactobacillus sakei I154 (sakacin) i Leuconostoc mesenteroides E131 (leucocin) kao i zaštitne kulture Lactobacillus sakei I151 u poboljšanju sigurnosti i kakvoće tradicionalno fermentiranih bosanskih, mađarskih, srpskih i hrvatskih kobasica. MATERIJAL I METODE Nadjev kobasica inokuliran je s L. monocytogenes (104-105 CFU/g) te jednim od polu-pročišćenih bakteriocina (sakacin i leucocin; aktivnost 1280 AU/kg). Kobasice su uzorkovane 0., 3., 7., 14. i 28. dana zrenja, a određivan je ukupni broj bakterija, L. monocytogenes, bakterija mliječne kiseline te pH. Nadalje, u drugom dijelu istraživanja nadjev je inokuliran zaštitnom kulturom Lb. sakei I151 i/ili bakteriocinom Ln. mesenteroides E131 radi ocjene utjecaja na senzorna svojstva kobasica. REZULTATI I DISKUSIJA Dodatak bakteriocina utjecao je na smanjenje ukupnog broja bakterija samo u srijemskoj kobasici. Broj bakterija mliječne kiseline nije se značajno smanjio, osim u srijemskoj i hrvatskoj kobasici, uz dodatak sakacina. U svim istraživanjima utvrđeno je da bakteriocini nisu utjecali na promjene pH nadjeva. Uspoređujući rezultate inhibicije L. monocytogenes, evidentno bolji učinak postignut je dodavanjem bakteriocina Ln. mesenteroides E131. Primjenom Lb. sakei I151 samog ili u kombinaciji s leucocinom specifična senzorna svojstva kobasica ostala su očuvana. ZAKLJUČAK Bacteriocin Ln. mesenteroides E131 (leucocin) postiže bolji antimikrobni učinak u fermentiranim kobasicama od bakteriocina Lb. sakei I154 (sakacin). Dodavanjem bakteriocina nije utvrđen negativan utjecaj na senzorna svojstva kobasica

Antilisterijski efekat dodatog Lactococcus lactis ssp. lactis tokom proizvodnje mekog belog sira

This study examined strains of lactic acid bacteria isolated from Zlatar cheese produced by the traditional method. Conventional microbiological testing resulted in the isolation of 96 strains of lactic acid bacteria which were then subjected to molecular genetic tests. One of the isolates, designated as Lactococcus lactis ssp. lactis, showed a markedly antilisterial effect under laboratory conditions. Based on the results, further research involved determination of its potential antilisterial effect during soft white cheese production. During fermentation that lasted 21 days, in experimental cheeses inoculated with Listeria monocytogenes ATCC 19111 combined with Lc. lactis spp. lactis culture, there was a reduction in Listeria cell count (by 3-4 log units), which can be considered important potential for biological control in soft white cheese production.U radu su ispitivani sojevi bakterija mlečne kiseline izdvojeni iz zlatarskog sira, koji je proizveden u skladu sa načelima tradicionalne proizvodnje. Primenom klasičnih mikrobioloških testova izolovano je 96 sojeva bakterija mlečne kiseline, koje su zatim podvrgnute molekularno genetskim ispitivanjima. Jedan od izolata, koji je označen kao Lactococcus lactis ssp. lactis ispoljio je u laboratorijskim uslovima izražen antilisterijski efekat. Na bazi tih rezultata vršena su dalja istraživanja radi utvrđivanja njegovog potencijalnog antilisterijskog efekta tokom proizvodnje mekog belog sira. Tokom procesa fermentacije sira, koji je trajao 21 dan, u oglednoj grupi sira u koju je inokulisana Listeria monocytogenes ATCC 19111 zajedno sa kulturom Lc. lactis spp. lactis došlo je do redukcija broja ćelija listerije u siru (za 3-4 log), što se može smatrati znаčајnim pоtеnciјаlom biоlоške zаštitе u njegovoj prоizvоdnji

Primena prirodnih antimikrobnih jedinjenja u biološkoj zaštiti hrane

The use of certain micro-organisms, their metabolic products, as well as plant extracts, is based on the development of new technologies of biological conservation and protection, which application can contribute, on the one hand, to the standardization process of making food products with uniform and / or improved quality parameters, and on the other hand, the emergence of secure products with longer shelf-life. The quest for a natural alternative to food safety, in relation to the use of chemical substances, is one of the most important activities of the food industry which is determined by the request of modern consumer to consume a minimum of processed foods.Upоtrеbа оdrеđеnih mikrооrgаnizаmа, njihоvih mеtаbоličkih prоdukаtа, kао i bilјnih еkstrаkаtа prеdstаvlја оsnоvu rаzvоја nоvih tеhnоlоgiја biоlоškоg kоnzеrvisаnjа i zаštitе, čiја primеnа mоžе dоprinеti, s јеdnе strаnе, stаndаrdizаciјi prоcеsа izrаdе prеhrаmbеnih prоizvоdа sа uјеdnаčеnim i/ili unаprеđеnim pаrаmеtrimа kvаlitеtа, а sа drugе strаnе, nаstаnku bеzbеdnih prоizvоdа sа prоdužеnim rоkоm upоtrеbе. Potraga za prirodnom alternativom zаštitе hrаnе, u odnosu na upotrebu hemijskih supstanci, predstavlјa jednu od najvažnijih aktivnosti prehrambene industrije, koja je uslovljena zahtevom savremenih potrošača za konzumiranjem minimalno prerađene hrane

Effect of selected lab on L.monocytogenes during production of traditionally fermented sausages

Within the project “Safety of traditional fermented sausages: Research on protective cultures and bacteriocins” the task of Work Package 5 (WP5) was to produce traditional fermented sausages inoculated with pathogens using selected protective cultures and/or bacteriocins. As a result from previous work packages, three strains of Lactobacillus sakei (I-151, I-154 and I-155) showed bacteriocin-based antimicrobial activity against Listeria monocytogenes only. The Task 5.1. was production of fermented sausages inoculated with L. monocytogenes, together with the three selected protective cultures. Three batches of the indigenous sausages were prepared according to original recipes. For each batch four groups of sausages were produced: a positive control group (sausages inoculated only with L. monocytogenes), and three groups of sausages inoculated with L. monocytogenes and one of the three protective strains of Lb. sakei (I-151, I-154 and I-155). A slight advantage of the strain I-151 over the other two was observed in antilisterial activity, which may suggests that the three investigated strains represented just three isolates of the same bacteria. This hypothesis was supported by results of genetic investigation of bacteriocin determinants of the isolates carried out in WP3, where it was verified that all the Italian strains are subclones of the same population. Having in mind these results, it may be suggested to use only Lb. sakei I-151 as a protective starter culture in further experimental investigation

Stanje ekosistema za uzgoj pastrmke sa aspekta mikrobiološkog rizika

Control of microbiological status of ponds and a fish itself is of great importance while the aim of control is to detect indicators of faecal pollution and to evaluate the potential risk of consumption of contaminated aquacultural products. In this paper we investigated microbiological population of rainbow trout ponds, in trout itself and in sludge. Investigations were performed at the beginning of autumn, end of autumn and at the beginning of winter. Results indicated that microbiological status of the pond ecosystem was mainly satisfactory, although there were some sporadic cases of A.hydrophila on trout skin at the beginning of autumn

Effect of selected lab on L.monocytogenes during production of traditionally fermented sausages

Within the project “Safety of traditional fermented sausages: Research on protective cultures and bacteriocins” the task of Work Package 5 (WP5) was to produce traditional fermented sausages inoculated with pathogens using selected protective cultures and/or bacteriocins. As a result from previous work packages, three strains of Lactobacillus sakei (I-151, I-154 and I-155) showed bacteriocin-based antimicrobial activity against Listeria monocytogenes only. The Task 5.1. was production of fermented sausages inoculated with L. monocytogenes, together with the three selected protective cultures. Three batches of the indigenous sausages were prepared according to original recipes. For each batch four groups of sausages were produced: a positive control group (sausages inoculated only with L. monocytogenes), and three groups of sausages inoculated with L. monocytogenes and one of the three protective strains of Lb. sakei (I-151, I-154 and I-155). A slight advantage of the strain I-151 over the other two was observed in antilisterial activity, which may suggests that the three investigated strains represented just three isolates of the same bacteria. This hypothesis was supported by results of genetic investigation of bacteriocin determinants of the isolates carried out in WP3, where it was verified that all the Italian strains are subclones of the same population. Having in mind these results, it may be suggested to use only Lb. sakei I-151 as a protective starter culture in further experimental investigation