Untitled - MendelNet 2013 - Mendelova zemědělská a lesnická ...

MENDELNET 2013Republic. Essential oils and extracts were added first day to whey in different concentrations(Tab. 1). Treated whey was stored at 6°C. Microbiological analyses were performed on the secondday and then on the each following 7th day of analysis by pour plate method. Overview ofdetermined microorganisms is shown in the Tab. 2 together with the conditions of cultivation.The bacterial counts were expressed as colony forming units (CFU) in 1 ml and logarithm.Tab. 1: Addition of essential oils and extracts to goat wheyEssential oil/extractAdded volume [µl/100ml]Fennel 100Peppermint 2000Thyme 600Extracts 5000Tab. 2: Conditions of cultivationMicroorganisms (MO) Culture medium Conditions of cultivationTotal plate count (TPC) PCA with skimmed milk 30°C, 72 hoursColiform bacteria (Coli) VRBL 37°C, 24 hoursEnterococci (Ent) Compass Enterococcus Agar 44°C, 24 hoursAerobic (TMRae) and anaerobic PCA with skimmed milk(TMRan) thermo resistant MOThe manufacturer of the culture media is Biokar diagnostics, FranceRESULTS AND DISCUSSION30°C, 48 hours, TMRan underanaerobic conditionsCounts of microorganisms in whey control samples are shown in the Tab. 3. All essential oils andextracts were not tested on the same sample of whey. Therefore, account must be taken on the factthat each of the tested whey contained different initial numbers of microorganisms, from whichmicrobial counts subsequently developed during testing. Efficacy can-not be compared on the basisof values given in the Tab. 4 and the Tab. 5.Tab. 3: Counts of microorganisms (MO) in whey without added essential oil/extract [log CFU·ml -1 ]Repetition ofwheyDay ofobservationlog N [log CFU·ml -1 ]I.May281522281522Coli Ent TMRan TMRae TPC3,94 0,96 0,910,834,283,99 ND 1,410,696,582,56 ND ND0,806,242,44 ND 0,441,096,03II.June5,055,801,671,941,341,100,440,666,546,715,94 1,23 1,881,926,856,42 1,21 0,800,807,71ND = not detected, Coli = coliform bacteria, Ent = enterococci, TMRan = thermo resistant anaerobic MO, TMRae = thermo resistantaerobic MO, TPC = total plate count of microorganisms570 | P age