Thursday, 20 August 2015

Heated Canned Foods

Heated Canned Foods

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High acid foods with a pH < 3.7 undergo spoilage by__________

a. Saccharolytic anaerobe
b. B. coagulans
c. both (a) and (b)
d. do not undergo spoilage by microorganisms

The putrifactive anaerobes grow best in the__________

a. Low acid canned foods
b. Medium acid canned foods
c. High acid canned foods
d. Any of these

High acid foods with a pH above 5.3 are especially subjected to__________

a. Flat sour spoilage
b. Putrefaction
c. Both (a) and (b)
d. TA spoilage

Flat sour spoilage of acid foods is caused by__________

a. B. coagulans
b. B. pepo
c. both (a) and (b)
d. B. stearothermophillus

The most important kind of chemical spoilage of canned foods is the hydrogen swell which is favored by__________

a. Increasing acidities of foods
b. Increasing temperature of storage
c. Imperfection in the tinning and lacquering
d. All of these

The presence of viable non-spore forming bacteria in heat process canned foods indicates leakage of the container. Which of the following is responsible for the spoilage of leaky cans?

a. Plant equipment
b. Cooling water
c. Highly acidic medium
d. High sugar content

Sulfur stinker spoilage, caused by is uncommonly found in__________

a. Low acid foods
b. Medium acid foods
c. High acid foods
d. Any of these

Medium acid foods with a pH between 5.3 and 4.5 are likely to undergo__________

a. Flat sour spoilage
b. Putrefaction
c. Both (a) and (b)
d. TA spoilage

Which of the following strain(s), that grow in the jellies and candid fruits, are able to grow in sugar concentration upto 67.5%?

a. Aspergillus
b. Penicillium
c. Citromyces
d. All of these

The immediate source of the flat sour bacteria is usually the__________

a. Plant equipment
b. Sugar
c. Starch
d. Soil

The ability of B. coagulans to grow in tomato juice depends upon the__________

a. Number of spores present
b. The availability of oxygen
c. The pH of the juice
d. All of these

Acid foods with a pH between 4.5 and 3.7 usually are spoiled by__________

a. B. coagulans
b. Saccharolytic anaerobe
c. Both (a) and (b)
d. None of these

The butyric acid type of fermentation in acid or medium acid foods, with swelling of the container by the carbon dioxide and hydrogen gas is caused by__________

a. C. butyricum
b. C. pasteurianum
c. both (a) and (b)
d. C. sporogenes

Which of the following(s) is/are porteolytic or putrefactive decomposing proteins with the production of malodorous compounds such as H2S, mercaptans, ammonia, indole and skatole?

a. C. sporogenes
b. C. putrifaciens
c. both (a) and (b)
d. C. butyricum

Canned poultry is more often spoiled by__________

a. Putrefactive than by Saccharolytic Clostridia
b. Saccharolytic Clostridia than by putrefactive
c. Saccharomyces species
d. Micrococcus species

Canned sweetened condensed milk may become thickened by__________

a. Bacillus species
b. Clostridium species
c. Micrococcus species
d. Saccharomyces species

The canned acid foods such as pineapple, tomatoes and pears have been found spoiled by C. pasteurianum. Such spoilage is more likely when the pH of the food is__________

a. >4.5 
b. <4.5
c. >5.3 
d. <5.3

Which of the following species can cause bitterness, acidity and curdling in canned milk, cream and evaporated milk?

a. Bacillus
b. Clostridium
c. both (a) and (b)
d. Saccharomyces

Canned meat and fish exhibit spoilage by__________

a. Bacillus species
b. Clostridium species
c. Both (a) and (b)
d. Saccharomyces
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