FNH 200 Lecture Notes - Lecture 9: Canadian Food Inspection Agency, Charcuterie, Food Preservation
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In this lesson we will consider the use of microorganisms, mainly in fermentation
processes, in the production of foods in Canada and in other countries. You will learn
about the wide variety of foods that are produced with the aid of microorganisms and
future applications of biotechnological processes in food processing and preservation.
Upon completion of this lesson you should be able to:
Define the term "biotechnology"
Describe the beneficial role that microorganisms have in the production of
fermented foods and of food ingredients or additives
Outline the sequence of microbiological, chemical and physical changes that are
involved in the conversion of milk to cheese
Explain and compare the terms "biotechnology-derived foods" and "genetically
modified foods", and describe the position of the Canadian government on these
Articulate a personal set of values pertaining to use of biotechnology in foods
Excerpts from the Health Canada and the Canadian Food Inspection Agency
websites, related to "novel foods" and "genetically modified foods" (please see the
"Activity" at the end of the lesson for more details).
Microorganisms in Food Preservation
Microorganisms have been employed for centuries in food preservation. Early
practitioners of food fermentations were not aware that preservation of food was aided by
the actions of microscopic organisms growing in the agricultural or fisheries commodities
and producing preservative agents such as acids, alcohols and substances with
Within the broad classification of microorganisms as "the good, the bad, and the ugly"
(as discussed in Lesson 5), the microorganisms used in the production of fermented
foods are defined as "the good." These microorganisms produce beneficial effects in
foods as a consequence of their growth and metabolism in the food products.
What is the meaning of "biotechnology"?
"Biotechnology is an umbrella term that covers a broad spectrum of tools and
techniques, ranging from fermentation (bread, wine, cheese) to plant and
animal breeding, cell and tissue culture, antibiotic production and genetic
engineering. The traits of every organism are encoded in its genetic material
(DNA or RNA) which is organized into individual units called genes. Genetic
modification is achieved by changing the code or organization of the genetic
material of an organism. This includes, but is not limited to, moving a gene or
genes from one organism to another (this is commonly called genetic
From:"Frequently asked questions on genetically modified foods" Health Canada
What are the desirable products of biotechnology?
Biotechnology is a term that began to be used in the 1980s and 90s, to describe the
integrated use of biochemistry, microbiology and engineering sciences to utilize
microorganisms and cultured animal and plant tissue cells and cell components in the
production of desirable products. The definitions given above, from the websites of
Health Canada and the Canadian Food Inspection Agency, indicate that "biotechnology-
derived foods" includes food products obtained through a very broad spectrum of tools
In the food industry the desirable products are food products, ingredients and additives
as shown in the two columns in the following table:
FOOD PRODUCTS INGREDIENTS AND ADDITIVES
Fermented beverages (wine,
products (yogurt, specialty
cheeses, cheddar cheese)
products (salami, bologna,
Traditional fermented foods
(sauerkraut, soy sauce,
tempe, idli, miso)
Microorganisms are used for the production of fermented food products. But they are
also are cultivated as sources of enzymes and flavouring ingredients used in food
Xanthan gum, a stabilizer used in a variety of food systems, is extracted from
bacteria (Xanthamonas campestris) that in nature cause slime rot of cabbages.
During production of xanthan gum specific isolates of the bacteria are
grown in large fermenters under conditions designed to maximize
production of the bacterial slime that is then harvested and purified for
use as a thickening and stabilizing agent
Plant cell cultures are used to produce flavouring ingredients for use in foods. Cells
of specific plants are cultured in fermentation vessels under conditions that favour
production of specific flavour compounds and are then extracted from the culture
after the culture has been cultivated for the appropriate period of time.
Microorganisms can be used for the production of useful enzymes.
For example, bovine rennin or chymosin used in the production of
cheese is in short supply. Researchers in several countries have shown
that it is possible to transfer the gene which codes for rennin in the dairy
cow to a bacterial cell. The implanted gene is replicated with the
bacterial genetic material each time the bacterial cells divide. The
implanted rennin gene permits the bacteria to produce bovine rennin.
Rennin produced by means of bacterial fermentation is used widely in
cheese production in Canada, the United States and other countries.
Is food fermentation the same as biotechnology?
Although the word biotechnology is a new one, biotechnology has in fact been
practiced in the agriculture/food industries for thousands of years: Yogurt
production in India, bread and beer in Egypt. Thus, in the current vernacular,
sometimes food fermentation would be referred to as food biotechnology
although in reality food biotechnology has a wider meaning.
Definition of Fermentation
Fermentation, in the strictest sense, means "the breakdown of carbohydrates under
anaerobic (absence of oxygen) conditions." However, in a broader sense, fermentation is
often used to describe the anaerobic and aerobic breakdown of carbohydrates and
carbohydrate-like materials by microorganisms. In fermented foods, proteins and lipids
may be hydrolyzed and metabolized by microorganisms involved in the fermentation
When we speak of fermented foods we are speaking of foods which have been
produced with the aid of microorganisms. The changes that occur may not be solely
to the carbohydrate component of the foods, but will also likely involve microbially
induced changes to the proteins and lipids in the foods to create the desired colours,
flavours and textures characteristic of fermented foods.
Most fermented foods are not genetically engineered (see the above explanation of
genetic engineering and compare it to the definition of fermented foods).