INSTITUTO FEDERAL FARROUPILHA - Campus Santa Rosa
CURSO SUPERIOR TECNOLOGIA EM ALIMENTOS
Disciplina: Inglês instrumental Professora: Vera Lúcia Frantz
Fermentation in food processing
From https://en.wikipedia.org/wiki/Fermentation_in_food_processing
Grapes being trodden to extract the juice and made into wine in storage jars. Tomb of Nakht, 18th
dynasty, Thebes, Ancient Egypt
Fermentation in food processing is the process of
converting carbohydrates to alcohol or organic acids using microorganisms —
yeasts or bacteria — under anaerobic conditions. Fermentation usually implies that the
action of microorganisms is desired. The science of fermentation is known as zymology or
zymurgy.
The term fermentation sometimes refers specifically to the chemical conversion
of sugars into ethanol, producing alcoholic drinks such as wine, beer, and cider. However,
similar processes take place in the leavening of bread (CO2 produced by yeast activity), and
in the preservation of sour foods with the production of lactic acid, such as
in sauerkraut and yogurt.
Other widely consumed fermented foods include vinegar, olives, and cheese. More
localized foods prepared by fermentation may also be based on beans, grain, vegetables,
fruit, honey, dairy products, and fish.
History and prehistory
Conical loaves of bread left as grave goods, exactly as laid out in the Great Tomb at Gebelein, Egypt, 2435-
2305 BC.
Natural fermentation precedes human history. Since ancient times, humans have
exploited the fermentation process. The earliest archaeological evidence of fermentation is
13,000-year-old residues of a beer, with the consistency of gruel, found in a cave
near Haifa in Israel. Another early alcoholic drink, made from fruit, rice, and honey, dates
from 7000-6600 BC, in the Neolithic Chinese village of Jiahu, and winemaking dates from ca.
6000 BC, in Georgia, in the Caucasus area. Seven-thousand-year-old jars containing the
remains of wine, now on display at the University of Pennsylvania, were excavated in
the Zagros Mountains in Iran. There is strong evidence that people were fermenting alcoholic
drinks in Babylon ca. 3000 BC, ancient Egypt ca. 3150 BC, pre-Hispanic Mexico ca. 2000
BC, and Sudan ca. 1500 BC.
The French chemist Louis Pasteur founded zymology, when in 1856 he connected
yeast to fermentation. When studying the fermentation of sugar to alcohol by yeast, Pasteur
concluded that the fermentation was catalyzed by a vital force, called "ferments", within the
yeast cells. The "ferments" were thought to function only within living organisms. "Alcoholic
fermentation is an act correlated with the life and organization of the yeast cells, not with the
death or putrefaction of the cells", he wrote.
Nevertheless, it was known that yeast extracts can ferment sugar even in the
absence of living yeast cells. While studying this process in 1897, the German chemist and
zymologist Eduard Buchner of Humboldt University of Berlin, Germany, found that sugar was
fermented even when there were no living yeast cells in the mixture, by an enzyme complex
secreted by yeast that he termed zymase. In 1907 he received the Nobel Prize in
Chemistry for his research and discovery of "cell-free fermentation".
Uses
Beer and bread, two major uses of fermentation in food
Food fermentation is the conversion of sugars and other carbohydrates into alcohol or
preservative organic acids and carbon dioxide. All three products have found human uses.
The production of alcohol is made use of when fruit juices are converted to wine, when
grains are made into beer, and when foods rich in starch, such as potatoes, are fermented
and then distilled to make spirits such as gin and vodka. The production of carbon dioxide is
used to leaven bread. The production of organic acids is exploited to preserve and flavor
vegetables and dairy products.
Food fermentation serves five main purposes: to enrich the diet through development
of a diversity of flavors, aromas, and textures in food substrates; to preserve substantial
amounts of food through lactic acid, alcohol, acetic acid, and alkaline fermentations; to enrich
food substrates with protein, essential amino acids, and vitamins; to eliminate antinutrients;
and to reduce cooking time and the associated use of fuel.
WHAT’S IT ALL ABOUT?
1. Após a primeira leitura, do que trata o texto?
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TRANSPARENT WORDS
Em textos científicos é comum encontrarmos um grande número de palavras cognatas ou
“transparentes”, cuja forma e sentidos são iguais ou muito parecidos com o português e
auxiliam na compreensão do texto. Retire do texto: a) 5 palavras transparentes que são
relacionadas com o assunto de que o texto trata; b) 5 novas palavras transparentes que
você ainda não conhecia em inglês e que são palavras comuns e não necessariamente são
diretamente relacionadas com o assunto do texto.
a) ________________________________________________________
b) ________________________________________________________
READING FOR SPECIFIC INFORMATION
Retire do texto e escreva em inglês, nas linhas indicadas, as seguintes informações:
a) A fermentação pode ocorrer pela transformação de TRÊS PRODUTOS de uso
humano:
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b) A produção de álcool pode ocorrer através da utilização dos seguintes produtos:
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c) A mais antiga evidencia de fermentação na história:
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d) Exemplo de remanescente de um antigo processo de fermentação encontra-se hoje
na Universidade da Pensilvânia:
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e) Importante descoberta de Louis Pasteur: ___________________________________
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f) RESPONDA EM PORTUGUÊS. A fermentação de alimentos serve para:
1) ______________________________________________________________
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2) ______________________________________________________________
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3) ______________________________________________________________
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4) ______________________________________________________________
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5) ______________________________________________________________
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