When the miracle became science

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Chemical reactions: foundations

Reading and listening

When the miracle became science

The earliest evidence of the production and consumption of wine is found in a ceramic vase found in the Zagros mountains (in what is now Iran and Iraq) which is dated around 5400 BCE. Traditionally wine, and even more so its production process, has been related to the mysterious and divine. In fact, both the Greeks and later the Romans had a god of wine and vineyards: Dionysus and Bacchus, respectively. These beliefs changed, developed and eventually disappeared with the help of logic and curiosity. This meant that in the Middle Ages it was thought that wine resulted from the decomposition of matter (grape juice), while in the 19th Century it was discovered that wine was the result of a chemical reaction: fermentation. The French chemist Louis Pasteur was the first person to explain fermentation, and thereby provided a scientific basis for the production of wine. This chemical change involves the transformation of sugar (glucose) into ethyl alcohol and carbon dioxide, which occurs due to the activity of yeasts (fungi) such as Candida, Pichia, Zygosaccharomyces or the popular Saccharomyces cerevisiae. There is now a science that specialises in the study of these chemical process. Do you know what it’s called? 1 Who was the Greek god of wine? 2 What chemical reaction is responsible for the production of wine? 3 When was fermentation discovered? 4 What turns into what in the fermentation process? 5 What are the main organisms responsible for fermentation?

Speaking

2020 was a disastrous year for the vineyards of Galicia, Catalonia, Castille-La Mancha and Andalusia, due to a plague of the fungus Plasmopara viticola. This causes powdery mildew, which generally requires treatment with fungicides to save the harvest. You are going to prepare a presentation for farmers that: • Explains the SDGs that are relevant to the issue and how they can help the farmers • Explain at least one alternative treatment for fighting mildew

I recommend that you try an alternative to fungicides such as

Writing

The following is a paragraph taken from an article that tells us about the causes and repercussions of the powdery mildew. In pairs, fill in the missing verbs. The weather ________ many challenges over the year with very few regions getting off lightly. It ______ a much wetter year, especially for coastal regions, and generous spring rains _________ with warmer temperatures than usual. This ________ the ideal conditions for mildew which ________ intense work in the vineyard but ultimately this impacted more on yield than quality. Finally, drier weather and higher summer temperatures _____ mildew retreat. Every stage of vine development took place earlier than usual and harvest dates _____ generally up to 14 days earlier _______ to a typical year. A few days of rain favoured the last stages of the ripening period for many regions without disrupting the harvest. One exception to this ______ Ribera del Duero where rain _____ frequent breaks in the harvest and difficult decisions over whether to pick or wait. Verbs: coincide, compare, is (three times), bring, provide, see, cause, require Source: https://www.foodswinesfromspain.com/spanishfoodwine/ LANGUAGE BANKLANGUAGE BANKLANGUAGE BANKLANGUAGE BANKLANGUAGE BANKLANGUAGE BANKLANGUAGE BANK LANGUAGE BANKLANGUAGE BANK LANGUAGE BANKLANGUAGE BANK LANGUAGE BANK global/whats-new/features/feature-detail/spain-2020-wineharvest.html 123