An Evaluation of the Role of Microbiological Criteria for Foods and Food Ingredients (1985) / Chapter Skim
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1 Introduction
1 Introduction
Pages 41-54
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From page 41... ...
MICROBIAL ACTIVITIES IN FOODS Historical Aspects During their existence, human beings have been confronted with the problem of limited shelf-life of animal and plant foods in part due to 41
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From page 42... ...
For example, refrigerated perishable foods such as milk, fresh meat, poultry, fish, fruits, tat ~~ r and vegetables lose some quality characteristics during normal storage and ultimately spoil, due in part to the activity of microorganisms capable of growth at refrigeration temperatures. Usually, extensive microbial growth (millions of organisms per g or cm2)
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From page 43... ...
Shelf-stable foods are not necessarily sterile; indeed, many do contain microorganisms. Some shelfstable canned foods may undergo microbiological spoilage if they are exposed to elevated temperatures permitting the growth of surviving thermophilic sporeforming bacteria, whereas these organisms are inactive at ambient temperatures and indeed tend to die during normal storage.
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From page 44... ...
The normal flora of severely heat processed, but not sterilized, low-acid canned foods is comprised of thermophilic sporeforming bacteria, the most heat-resistant microbial components of the raw materials. The predominating flora of shelfstable canned cured meats consists of mesophilic aerobic and anaerobic sporeforming bacteria, the predominant organisms resistant to the heat process applied to these products.
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From page 45... ...
It follows that since most classes of perishable foods constitute selective environments for rather restricted groups of microorganisms, the spoilage caused by the growth of these microorganisms manifests itself in a characteristic manner, i.e., normal spoilage pattern. For example, when pseudomonads and other closely related gram-negative psychrotrophic aerobic bacteria grow to large numbers on the surface of refrigerated fresh meat, poultry, and fish, sensory changes occur.
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From page 46... ...
Effective food control programs eliminate the potential for foodborne illness in a variety of ways. Processing techniques that cause destruction of pathogens may be employed, e.g., the pasteurization of milk to destroy Coxiella burnetii and Mycobacterium tuberculosis and less heat resistant pathogens such as the diphtheria bacillus, salmonellae, and pyogenic streptococci, and the 12-D process for the destruction of C
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From page 47... ...
Extensive microbiological control procedures are needed to produce "cultured products" of high quality and to ensure that the microbial activities are guided in such a manner that the end products have the desirable sensory properties. For example, in cultured dairy products this is achieved by (1)
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From page 48... ...
Negative tests convey to food handlers, managers, and public health personnel the erroneous concept that the workers are free of infections and therefore incapable of transmitting foodborne pathogens to the foods they handle. Although direct transfer of pathogens from food handlers to food is a hazard, far more frequently improper food-handling practices create a hazard that is not circumvented by health examinations.
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From page 49... ...
Resident inspectors observe all phases of processing from the live animal to the finished product. Little reliance is placed upon microbiological testing in the meat and poultry control programs.
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From page 50... ...
, and the use of indicator organisms for pathogens (see Chapter 51. Composite Programs Sophisticated microbiological control programs encompass the three approaches, namely education and training, inspection of facilities and operations, and microbiological testing.
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From page 51... ...
As discussed in Chapter 10, use of the HACCP system by industry not only offers the food processor a rational approach to microbiological control, but also leads to more effective and economical utilization of regulatory manpower. The inspector focuses initial attention on monitoring records and, if the results indicate satisfactory control over critical control points, logically concludes that efforts could be more effectively expended on other foodprocessing operations either with the same or with other food-processing plants.
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From page 52... ...
Despite this lack, existing laws provide sufficient authority for the removal from the marketplace of products with microbiological conditions that pose a threat to health. Therefore, "implied" microbiological standards do exist.3 Even in the absence of a threat to health, existing federal laws provide sufficient authority for seizure of products if there is direct or indirect evidence that a product is contaminated with filth, e.g., seizure of tree nuts contaminated with E
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From page 53... ...
These criteria are included in purchase contracts between vendors and purchasers of products. Industry "standards" exist for certain raw materials, the best examples being the National Food Processors Association standards for sporeforming bacteria in sugar and starches and the National Soft Drink Association standard for the presence of yeasts, molds, and bacteria in sugar.
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From page 54... ...
1964 An Evaluation of Public Health Hazards from Microbiological Contamination of Foods. Food Protection Committee.
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