Lovran 06

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COLD AND HEAT STERILIZATIONOF GOATS AND COWS
WHEY influence on properties, composition and
inhibitory action against selected pathogens
Vedran Slacanac1, Jovica Hardi1, Mato Vlainic2,
Mirela Lucan1, Hrvoje Pavlovic1
1 Faculty of Food Technology, 31000 Osijek 2
Apimel d.o.o., E. Kvaternika 131, 31220
Vinjevac
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Functional properties of whey and whey components

• Whey proteins and amino acids play role in
  increasing muscle mass in conjuction with
  appropriate training
• Results of some earlier studies suggested
  anabolic effect of whey proteins and amino acids
• Some constituents of whey, such as minerals and
  SCFA (MCFA), have been shown to regulate nutrient
  partioning, adiposity and body composition
• Whey and whey-derived bioactive compounds have
  been studied for their ability to enhance general
  health

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Possibilities of manipulatingthe composition of
the gut microfloraby foods 2nd generation of
functional food
PROBIOTICS ? living microorganisms which (when
ingested or locally applied) confer one or more
demonstrated health benefits for consumer
WHEY FERMENTED WITH PROBIOTICS ? 2nd generation
functional food with high nutritive and possible
therapeutic value
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HYPOTHESES

• Whey could be a good probiotic fermentation
  medium
• Heat treatment of fermented whey could have
  important influence on composition of whey, as
  well as on content of some bioactive compounds
• Antagonistic action of goat and cow whey
  fermented with probiotics against some potential
  pathogens has been proposed

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MATERIALS AND METHODS
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PREPARATION OF GOATS AND COWS WHEY
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1. Fermentation of goats and cows whey
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2. Gross chemical composition of goat and cow
wheys

• Ash, total nitrogen, fat and lactose were
  determined on MILCOSCAN FT 120 (FOSS ELECTRIC,
  Denmark)
• Nonprotein nitrogen was determined by Kjeldahl
  analysis after selective precipitation in TCA
  (McKellar, 1981)
• pH values were determined on MA 235 pH/Ion
  Analyzer (METTLER TOLEDO) titratable acidities
  were determined by standard Soxhlet-Henkel method

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3. Measuring during whey fermentation

• pH values (MA 235 pH/Ion Analyzer)
• CFU of Bifidobacterium longum Bb-46 and
  Lactobacillus casei 01
• C4 C12 fatty acid contents (GC/FID method)
• a), b) every 4 hour of fermentation
• c) before fermentation, at the end of
  fermentation process

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MICROBIOLOGICAL ANALYSIS
CFU of Bifidibacterium longum Bb-46

• Modificated Bifidobacterium medium (Pavlovic et.
  al., 2006)
• Anaerobic conditions (ANAEROBIC JARS)
• Incubation on 37 0C from 48 hours

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CFU of Lactobacillus casei -01

• Standard microbiological method on MRS agar
  (MERCK KGaA, Germany)
• Seminaerobic incubation in air-tight vessels
• Incubation on 37 0C from 48 hours

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4. Elimination of bacterial cells from fermented
whey pasteurization (P) and microfiltration (MF)

• (1) HEAT TREATMENT
• Pasteurization
• at 80 C/5 min

(2) MICROFILTRATION On Sartorius MF
laboratory-plant (Sartorius, Germany) (pore size
0.45 ?m, pressure 1.5 bar)
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5. Antagonistic activity against Escherichia coli
and Listeria monocytogenes
EXPERIMENTAL DESIGN
Known number of E. coli, L. monocytogenes cells
(24-h-old culture on nutrient agar)
Sweet goat (cow) whey acidified with HCl to
analyzed samples acidity (control samples)
Mixture of goat and cow unfermented whey
Fermented whey with probiotic cells
Fermented and MF whey
Fermented and P whey
Determination and enumeration on selective agar
plates (Endo agar and Tryptic Soy agar)
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6. Antibiotic assay

• Standard method for Antibiotic sensitivity test
  (1 colony in 5 ml of sterile physiological saline
  solution, Mueller-Hinton agar for detection)
• Tested antibiotics NORFLOXACIN, OFLOXACIN
  (kinolon), TETRACYCLIN
• Tested probiotics goat and cow whey fermented by
  the use of B. longum Bb-46 and L. casei -01
  native, MF and pasteurized
• Oportunistic microorganisms E. coli, L.
  monocytogenes
• Dosing of probiotics antibiogram susceptibility
  discs (diameter 12.7 mm producer Schleicher
  Schuell, Germany)

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RESULTS
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Chemical composition and acidity of sweet goat
and cow whey
SD standard deviation Mean value of 20
determination
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Changes of Bifidobacterium longum Bb-46 CFU
during the fermentation of goat and cow whey
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Changes of pH values during the fermentation of
goat and cow whey with B. longum Bb-46
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Changes of Lactobacillus casei -01 CFU during the
fermentation of goat and cow whey
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Changes of pH values during the fermentation of
goat and cow whey with L. casei -01
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Changes in gross chemical composition caused by
elimination of cells from fermented whey (B.
longum)
P pasteurization MF microfiltration N
whey with bacterial cells high value of SD
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Changes in gross chemical composition caused by
elimination of cells from fermented whey (L.
casei)
P pasteurization MF microfiltration N
whey with bacterial cells high value of SD
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Changes in SCFA and MCFA concentration caused by
elimination of B. longum cells from fermented whey
A before fermentation B fermented whey P
pasterized whey MF microfiltered whey
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Loss in SCFA and MCFA contents caused by
elimination of B. longum cells from fermented whey
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Inhibition of E. coli in vitro growth
N whey with bacterial cells MF microfiltered
fermented whey P pasteurized fermented whey
C control acidified whey
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Results of Antibiotic assay B. longum (samples
after 48 h of storage, Tstorage 46 C)
N whey with bacterial cells MF microfiltered
fermented whey P pasteurized fermented whey
C control acidified whey distinctive
(measurable) inhibition zones better
expressed inhibition zones inhibition zones
were not clearly expressed
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Results of Antibiotic assay - L. casei (samples
after 48 h of storage, Tstorage 46 C)
N whey with bacterial cells MF microfiltered
fermented whey P pasteurized fermented whey
C control acidified whey distinctive
(measurable) inhibition zones better
expressed inhibition zones inhibition zones
were not clearly expressed
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CONCLUSIONS

• There was no significant differences in
  composition between goat and cow sweet whey (only
  in NPN contents)
• Results shown that both types of sweet whey are
  very suitable mediums for B. longum and L. casei
  growth
• Pasteurization influenced on certain changes in
  composition of fermented goat and cow whey
  (contents of NPN, contents of fat in whey), as
  well as to decrease of pH value of fermented whey

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CONCLUSIONS

• Increase of all the examined SCFA and MCFA in
  fermented goat milk was statistically
  significantly higher than in fermented cow milk.
• Pasteurization strongly influenced to loss of
  SCFA and MCFA contents in fermented goat and cow
  whey
• Microfiltration insignificantly influenced on
  SCFA and MCFA contents in fermented whey
• Goat and cow whey fermented with selected
  probiotic strains strongly inhibited the growth
  of E. coli and L. monocytogenes in comparison
  with control acidified whey samples

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CONCLUSIONS

• Pasteurization of fermented whey significantly
  influenced on decrease of inhibitory potential
  against E. coli and L. monocytogenes
• Microfiltration did not influence on inhibitory
  potential of fermented goat and cow milk
• Results of antibiotic (probiotic) sensitivity
  tests partially confirmed the results of
  microbiological analysis L. monocytogenes was
  high sensitive to presence of fermented goat and
  cow whey, well considerable lower level of
  sensitivity of E. coli was noted.

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Antibiotic assay L. monocytogenes MF, N,
goat whey