Midterm 2 short q Flashcards
The typical spoilage for juices/liquids are:
Yeasts
For which food specified the annual number of sample based on the animals slaughtered in the previous year?
Cattle, Swine, Sheep and Goats
What is not true for gas chromatography?
It is suitable for separating maximum 50-70 different components
It cannot be connected with a structure elucidation method
What considerations should be taken into account by the person taking the sample?
What is the size and amount of material to be sampled
What is the level of inhomogeneity of the material to be sampled
What is the target component or components
What is true for gas chromatography?
A gas is used as its mobile phase
Heat sensitive materials can also be analysed by it
What is produced during homofermentation?
Lactic acid
From which one do you not take 500 gram sample?
Fresh fruit
Which substances belongs to category A?
Chloramphenicol, anabolic agents
What is true for the spoilage flora?
Aerotolerant anaerob
Which heat treatment is not used to produce consumer milk?
Thermization
What is not produced during heterofermentation?
Malic acid
For which heat treatment are the phosphatase and peroxidase tests both positive?
Thermization
From which one do you take 500 gram sample?
Meat
On which pH is a certain acid most/less active?
Lowest/highest number
Which if these cannot be contaminated during the first phase of food production?
Milk poducts/sausage
What is the principle of testing for Peroxidase test (Storch test)?
Control of heat treatment, peroxidase decomposes at 80oC (e.g. flash pasteurization)
What is the Z-value?
Change in temperature, which results in a tenfold change in the Decimal reduction time (D)
What is the D?
The time for the (surviving) population to be reduced by 1 magnitude at a specified, constant temperature. Decimal reduction time (e.g. 107 – 106 = 1D)
Which milk product is made using thermofilic and mesophilic bacterias?
Yoghurt (acidified milk products fermented by thermophilic bacteria, origin from the Balkans)
Which test is suitable to examine the quality/originity of the milk?
Fourier transformation infrared spectroscopy, Milko-Scan. Eliminate need for traditional slow tests
For which heat treatment is phosphatase test negative and peroxidase test positive?
Pasteurization below 80oC
Which is made with mesophilic bacteria?
Curd, Kefir, Koumiss, Yoghurt
Which is made of mesophilic bacteria and yeasts?
Kefir, Koumiss
What do we detect with alcohol test?
When the milk is sour (increased SH), the colloidal system changes ➡ proteins precipitate by the effect of 68% alcohol
How do we detect milk falsification?
If foreign water is meant ➡ by determination of freezing point
Which test is based on microbiological inhibition?
Delvo test, Four-cup-plate, KIS test, Brilliant Black Reduction test
Which test is based on receptor reactions?
ROSA test, Snap test
What drug is in group A?
- Chloramphenicol (also anabolic substances e.g hormones, stilbene, nitrofuran, tyreostatics, zeranol, beta agonists)
What sample you DON’T take in primary sampling? A Milk-B meat-C urine-D water
- C urine
From what do you take a sample of 500g?
- Mammal meat (also mammal fat, any meats, processed foods, cheese)
Which sample’s quantity correlates with the last year’s output?
- Cow milk (also eggs)
What is not true for an assay with roots in suspection?
Idk, there was pharma metabolites, i wrote that
- When there is a suspicion, sample is taken from the suspected contaminated food/product in order to detect food borne disease and poisonous source
In what range of light can you get information about quantity?
(Maybe IR, but just maybe :D)
- If question refers to electromagnetic radiation: Infrared, uv, xray, visible
What is true about mass spectroscopy?
sample is converted into ions, high sensitivity, low detection limit, only a
small amount of sample required.
What is true about atomspectroscopy?
sample is converted into atomic state and light absorption is measured.
For what would you use molecular spectroscopy?
- Quantitative analytical purposes?
What kind of microflora is used in curd?
- Curd: mesophilic lactic acid bacteria
- Kefir, Koumiss: lactic acid bacteria and yeast
- Yoghurt: thermophilic lactic acid bacteria
What is that NOT gets contaminated primarily?
Grout meat (primarily refers to raw products e.g. milk) – Grouse meat??
What paint (stain) can paint the lactate producing bacteria?
Methylene blue
What method roots in receptor binding?
Rosa (also snap test)
What method has roots in microbe inhibition?
KIS (also fourplate, delvo test, brilliant black reduction test)
What’s the colour of a positive DELVO test?
Purple (negative: yellow)
Which method would you use for protein definition in milk?
Klejdahl method, formal titration, FTIR (fourier transformation infrared spectroscopy)
What method would you use to find out if there was cheating with milk?
- Density measurement (density decreases when foreign water added, inceases when milk is skimmed)
- Freezing point (increases when foreign water added)
What is the method that shows if the milk was heat-treated or not?
Phosphatase or peroxidase test
Which is the durable permanently (?) milk?
UHT
HACCP-basically what is this, cant remember the exact q
Hazard analysis critical control point (food safety regulation system applicable to the entire food chain, increases efficiency, enables cost-effective management, preventative approach rather than control)
In faecal contamination of water which microbe do you search for? -Strept. faecalis, or Clost. Perfringens
Streptococcus faecalis (also E.coli)
What is the primary source of yersinia enterocolitica?
Raw pork
Which has the lowest aw?
Moulds
Culture used in yoghurt?
Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria
Which is based on last years production?
Poultry
Which CANNOT be contaminated during primary production?
Sausage
Which is NOT tested for during production?
Animal, feed, blood, sausage
Alcohol test used for?
Examiantion of freshness and acidity
pH sorbic acid works best at?
(choose lowest pH value)
FALSE for objective program?
With risk evaluation (targeted)
NOT produced in heterofermentation?
Malic acid
Adulteration of milk?
Determination of density of raw milk
Define D value?
The time for (surviivng) population to be reduced by 1 magnitued at a specific temp.
Group A?
Anabolic
Which does NOT have a sample size of 500g?
Fruit
Which is microbioloigcal growth inihibiton?
Delvo test
What is milk seperated into?
Cream and skimmed milk
Receptor based test?
ROSA
Oxygen preference of spoilage flora?
Aerotolerant anaerobes
Which is used to determine the potential acid degree?
Sochelt Henkel method
What is made from bacteria and yeast and is of Caucasian origin?
Kefir
What test is used to detect fat/determine fat?
Gerber method
When is sorbic acid less effective?
At a high pH
microbial growth inhibition test:
KIS
cannot be contaminated primary production:
minced meat
