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Frequently Asked Questions


In this article you will find an answer to frequently asked questions on the topics covered during this week.

1. Are all cheeses fermented?

Yes, all cheeses are fermented, from soft cheeses (like cottage cheese, mozzarella, and others) to the long ripened cheeses like Parmigiano and Grana. Emmental is fermented as well, the holes it contains are gas bubbles created by fermentative bacteria (called Propionibacterium) producing carbon dioxide.

2. What type of fermentation occurs with coffee and tea? I don’t think these have sugars which need to be transformed and understand that heat is used to dry or roast the leaves/beans?

The fermentation of coffee takes place when the seed (bean) is still in the coffee fruit ‘cherry’. The cherries are collected and before the separation of the seed (green coffee) there is a short fermentation which can be wet (in water) or dry. Basically, the cherry is broken and the pulp is left in contact with the seed. The sugars contained are fermented mainly by yeasts.

With regards to tea, the enzymatic activity, coming from the leaves, impacts the final quality of the tea (high oxidative activities). Fermentation occurs because of the use of some low level sugars contained in the leaves. Lactic acid bacteria are usually found in these ecosystems.

3. Are all sausages fermented, or just certain types of sausage and, if so, which ones?

Actually, here there is an issue with the language and terminology since in England ‘sausages’ are not fermented. However, Salami and pepperoni are fermented. There is a lot of variety of products in the different countries and that’s why is difficult to use a strict terminology.

4. Why are bananas grouped with high resistant starch foods?

Unripe bananas are rich in resistant starch, which is gradually lost during ripening. Read more about levels of RS in bananas in the See Also section.

5. How far off are we from getting a camera that could be used instead of colonoscopy or gastroscopy?

Camera pills are already in use in some areas of the world. See this post from Cancer Research UK for more information.

UK Government guidelines say our dietary fibre intake should increase to 30g a day, as part of a healthy balanced diet. As most adults are only eating an average of about 18g day, so we need to find ways of increasing our intake. In Europe, for adults, the recommended amounts of dietary fibre for promotion of adequate laxation and for prevention of NCDs such as diabetes type 2, colorectal cancer, CVD or of overweight and obesity range from 25 to 38 grams/day. Find more information in the See Also section.

7. Can you provide further reading on research into Resistant Starch?

Sure, please scroll down to the See Also section.

8. How do other grains used in the past, such as spelt and emmer, compare for Resistant Starch?

See this paper where the authors compare spelt and common wheat varieties or RS, but also looked at the breads made out of these grains.

9. Can you provide further reading to go with the video on “Impact of diet in shaping gut microbiota” activity 2.14?

Sure, please scroll down to the See Also section.

10. Probiotics vs fermented foods, can you summarise the difference?

Probiotic is a microbial strain that has scientifically proven benefits for human health. The products that contain probiotics can be labelled as probiotic food and should follow strict rules for the labelling. Fermented products most of the times do not contain probiotic bacteria. They contain live bacteria which not necessary are probiotics.

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The Human Microbiome

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