part of the normal flora of the mammalian skin & found in water, soil, air, food & weak proteolytic properties - some couse sweet curdling of milk & constant meat microflora: curing (contribution to development of curing colour and flavour in meat products)

nonmotile, sensitive to antibiotics & phatogenic species cause mastitis & pyoderma of skin and wounds

Enterococci are resistant to preservatives & Enterococci are resistant to antibiotics & Enterococci exhibit amino acid decarboxylating activity – biogenic amines (histamine)

occur in pairs or tetrads, nonmotile, senstitive to antibiotics & catalase and oxidase(-), incapable of reducing nitrate

facultative anaerobes, mesophiles, lactic acid homoformentation & found in meat, green parts of plants

facultutive anaerobes or microaerophiles, mesophiles and thermophiles & found on mucous membranes, digestive system, plant material, milk, meat

propionic acid fermentation: propionic acid, acetic acid, CO2 & synthesis of vitamin B12 & antimicrobial metabolites & some are probiotic

aerobes and facultative anaerobic bacteria, catalase (+) & found in soil, air, raw materials, water

heat-resistant spores: efficiency of thermal processes & capable of: reduction of nitrates & capable of: breakdown sugars (oxidation) & capable of: hydrolysis of proteins and lipids

Food And Feed Preservation - Overview

The microorganisms related to food & feed safety, preservation, and fermentation processes. Basics about those MO and information on quality and microbiological safety, the role of lactic acid bacteria, protective cultures...The fundamental aspects of the biologically viable methods for food and feed preservation.

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This flashcard set provides an overview of food and feed preservation techniques at a university level, focusing on various bacteria, their roles, and processes like fermentation, acid production, and enzyme activity. It covers topics such as the use of catalase and oxidase, the impact of anaerobes, and the production of antibiotics. Ideal for students and professionals in biology, this flashcard set offers insights into the microbial processes crucial for preserving food and feed, helping them understand the science behind these preservation methods.

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Which of these foods will spoil the fastest?

intact foods

foods with a low pH

processed foods

moist foods

Micrococcus luteus is ...

an obligate aerobe, oxidase (+), coccus, tetradarranging, pigmented (carotenoid pigments)

an obligate aerobe, oxidase (+), bacillus, tetradarranging, pigmented (carotenoid pigments)

an obligate anerobe, oxidase (+), coccus, tetradarranging, pigmented (carotenoid pigments)

an obligate aerobe, oxidase (-), coccus, tetradarranging, pigmented (carotenoid pigments)

an obligate anaerobe, oxidase (+), bacillus, tetradarranging, pigmented (carotenoid pigments)

Micrococcaceae 2

part of the normal flora of the mammalian skin

found in water, soil, air, food

weak proteolytic properties - some couse sweet curdling of milk

hygiene microbiological indicators of water, food and technological processes

constant meat microflora: curing (contribution to development of curing colour and flavour in meat products)

Staphylococcus 1

facultative anaerobes, catalase(+), oxidase(-)

facultative anaerobes, catalase(-), oxidase(-)

facultative aerobes, catalase(+), oxidase(-)

facultative anaerobes, catalase(+), oxidase(+)

facultative aerobes, catalase(+), oxidase(-)

Staphylococcus 2

found on the animal and human skin and mucous membranes, in water, soil, air, food

resistant to antibiotics: plasmid encoded antibiotic resistance and transfer

sensitive to disinfectants

constant meat microflora: curing (contribution to development of curing colour and flavour in meat products)

reduction of nitrates, decomposition of proteins or amino acids

Staphylococcus aureus ...

is a caogulase(+) pathogen

produces heat-resistant enterotoxin

is obligate aerobe, oxidase (+)

is a coccus, tetradarranging

is pigmented (carotenoid pigments)

Saprophytic species are used as starter cultures:

S. xylosus

S. carnosus

S. aureus

S. luteus

S. marcescens

Streptococcus 1

nonmotile, sensitive to antibiotics

nonmotile, catalase (+), oxidative metabolism of sugars to water and CO2, reduce nitrates

catalase and oxidase(-), incapable of reducing nitrate

found on oral mucous membranes; in milk

found on the animal and human skin and mucous membranes, in water, soil, air, food

Streptococcus 2

nonmotile, sensitive to antibiotics

produces heat-resistant enterotoxin

facultative anaerobes, catalase(+), oxidase(-)

phatogenic species cause mastitis & pyoderma of skin and wounds

weak proteolytic properties - some couse sweet curdling of milk

What is true about these Streptococci?

S. thermophilus is a thermophile Streptococcus

S. bovis is found in ruminant digestive system

S. pyogenes (a betahemolytic streptococci) is a phatogenic species

S. carnosus is found in raw meat

S. xylosus metabolizes xylose

Lactococcus 1

nonmotile, sensitive to antibiotics

partially motile, sensitive to antibiotics

catalase and oxidase(-), incapable of reducing nitrate

catalase and oxidase(+), incapable of reducing nitrate

catalase and oxidase(+), capable of reducing nitrate

Lactococcus 2

facultative anaerobes, mesophiles, lactic acid homoformentation

facultative aerobes, mesophiles, lactic acid homoformentation

facultative aerobes, thermophiles, lactic acid homoformentation

facultative aerobes, thermophiles, lactic acid heteroformentation

facultative anaerobes, mesophiles, lactic acid heteroformentation

Lactococcus 3

found in milk, on green parts of plants

production of bacteriocins: Nizin

production of bacteriocins: Nitamycin

found in ruminant digestive system

found on the animal and human skin and mucous membranes, in water, soil, air, food

Lactococci used in food production:

L. lactis ssp. lactis

L. lactis ssp. cremoris

L. lactis ssp. cremosa

L. lactis ssp. lacta

L. lacti ssp. lactis

Enterococcus 1

nonmotile, resistant to antibiotics

partially motile, resistant to antibiotics

nonmotile, sensitive to antibiotics

catalase and oxidase(-), incapable of reducing nitrate

catalase and oxidase(+), incapable of reducing nitrate

Enterococcus 2

facultative anaerobes, mesophiles, lactic acid homofermentation

found in the animal and human digestive system

Resistant to high concentrations of NaCl

found in milk, on green parts of plants

facultative anaerobes, mesophiles, lactic acid heterofermentation

Enterococcus 3

thermoduric bacteria which can survive, to varying extents, the pasteurisation process

survive freezing process

do not survive freezing process

psychotroph bacteria which can survive, to varying extents, the pasteurisation process

psychoduric bacteria which can survive, to varying extents, the pasteurisation process

Enterococcus 4

Enterococci are resistant to preservatives

Enterococci are resistant to antibiotics

Enterococci are resistant to desinfectants

Enterococci exhibit amino acid decarboxylating activity – biogenic amines (histamine)

Enterococci exhibit weak proteolytic properties - some couse sweet curdling of milk

Enterococcus 5

possible transfer of antibiotic resistance genes

not allowed to be used in food production

allowed to be used in feed production

allowed to be used in food production

not allowed to be used in feed production

Leuconostoc 1

nonmotile, sensitive to antibiotics

nonmotile, resistant to antibiotics

catalase and oxidase(-), incapable of reducing nitrate

catalase and oxidase(+), incapable of reducing nitrate

catalase and oxidase(-), capable of reducing nitrate

Leuconostoc 2

facultative anaerobes, mesophiles, lactic acid heteroformentation

facultative aerobes, mesophiles, lactic acid homoformentation

facultative anaerobes, termoophiles, lactic acid heteroformentation

found in milk, on green parts of plants

found in the animal and human digestive system

Leuconostoc 3

used in production of dextran - produced in the glycocalyx covering the cells (synthetic blood plasma substitute, slime defects in food products)

capable of performing citrate fermentation (diacetyl - butter flavor)

cause flavor defect in the brewing industry

amino acid decarboxylating activity – biogenic amines (histamine)

resistant to high concentrations of NaCl

Pediococcus 1

occur in pairs or tetrads, nonmotile, senstitive to antibiotics

occur in triads or tetrads, motile, senstitive to antibiotics

occur in pairs or triads, nonmotile, resistant to antibiotics

catalase and oxidase(-), incapable of reducing nitrate

catalase and oxidase(+), capable of reducing nitrate

Pediococcus 2

facultative anaerobes, mesophiles, lactic acid homoformentation

facultative aerobes, thermophiles, lactic acid homoformentation

found in meat, green parts of plants

found in milk, green parts of plants

obligate anaerobes, mesophiles, lactic acid heteroformentation

Which of these Pediococci are used in starter cultures in the meat industry?

P. acidilactici

P. pentosaceus

P. pentosauce

P. acidilactococci

P. pentose

Lactobacillus 1

short or long rods, sensitive to antibiotics

catalase(-), incapable of reducing nitrate, high nutritional requirements

catalase(+), capable of reducing nitrate, high nutritional requirements

oxidase(+), short or long rods, resistant to antibiotics

catalase and oxidase(+), capable of reducing nitrate, low nutritional requirements

Lactobacillus 2

facultutive anaerobes or microaerophiles, mesophiles and thermophiles

facultutive aerobes or microaerophiles, thermophiles

obligate anaerobes or microaerophiles, mesophiles

found on mucous membranes, digestive system, plant material, milk, meat

found in meat, green parts of plants

Lactobacillus 3

lactic acid homofermentation

lactic acid heterofermentation

may cause spoilage defects – color defects in meat e.g. greening

some probiotic bacteria

starter culture component in meat industry

Lactobacilli exhibit antimicrobial activity through the following metabolites:

lactic acid

acetic acid

H2O2

bacteriocins

butyric acid

Propionibacterium 1

pleomorphism (X, Y, coccoid), facultative anaerobes, catalase(+), incapable of reducing nitrate

pleomorphism (X, Y, bacilloid), facultative aerobes, catalase(+), incapable of reducing nitrate

pleomorphism (X, Y, bacilloid or coccoid), facultative anaerobes, catalase(-), capable of reducing nitrate

found in rumen of cattle and sheep

found on mucous membranes, digestive system, plan material, milk, meat

Propionibacterium 2

propionic acid fermentation: propionic acid, acetic acid, CO2

propionic acid fermentation: propionic acid, butyric acid, CO2

synthesis of vitamin B12

antimicrobial metabolites

some are probiotic

Bacillus 1

aerobes and facultative anaerobic bacteria, catalase (+)

anaerobes and facultative anaerobic bacteria, catalase (-)

facultutive anaerobes or microaerophiles, catalase (+)

found in soil, air, raw materials, water

found on mucous membranes, digestive system, plant material, milk, meat

Bacillus 2

heat-resistant spores: efficiency of thermal processes

capable of: reduction of nitrates

capable of: producing antimicrobial metabolites (lactic acid, acetic acid, H2O2, bacteriocins)

capable of: breakdown sugars (oxidation)

capable of: hydrolysis of proteins and lipids

Bacillus 3

food spoilage: souring of canned meat and fish

food spoilage: souring of cheese

food spoilage: color defects in meat e.g. greening

food spoilage: color defects of canned meat and fish

food spoilage: color defects of dairy product

Pathogenic Bacillus species:

B. cereus (exotoxins)

B. anthracis (anthrax - biological weapon)

B. subtilis (exotoxins)

B. coagulans (endotoxins)

B. antraxis (anthrax - biological weapon)

Commercial-scale production of Bacillus for production of:

enzymes (amylases), antibiotics, insecticides

vitamins, hyaluronic acid, polygalacturonic acid

probiotic additives

polygalacturonic acid, acetic acid

hyaluronic acid, acetic acid

Saccharomyces sp .:

alcoholic fermentation in winemaking, brewing, distillation; Baker's yeast

fodder yeast

blue cheese (injected with spores) Camembert cheese, fermented sausages (salami)

enzymatic preparations

use for the production of butyric acid and solvents (e.g. butanol, acetone, isopropanol) and hydrogen

Candida sp .:

production of enzymes (amylases), antibiotics, insecticides

alcoholic fermentation in winemaking, brewing, distillation; Baker's yeast

fodder yeast

blue cheese (injected with spores) Camembert cheese, fermented sausages (salami)

enzymatic preparations

Penicillium sp .:

production of enzymes (amylases), antibiotics, insecticides

alcoholic fermentation in winemaking, brewing, distillation; Baker's yeast

fodder yeast

blue cheese (injected with spores) Camembert cheese, fermented sausages (salami)

enzymatic preparations

Aspergillus sp .:

production of vitamins, as well as other metabolites (hyaluronic acid, polygalacturonic acid)

alcoholic fermentation in winemaking, brewing, distillation; Baker's yeast

fodder yeast

blue cheese (injected with spores) Camembert cheese, fermented sausages (salami)

enzymatic preparations

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Food And Feed Preservation - Overview

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