yeast
/jiːst/ (bre, ipa) · /jiːst/ (ame, ipa) · /ˈyēst especially Southern and Midland US ˈēst/ (ame, mw)
yeast — noun
1. a type of microscopic fungus that people mix into bread dough so the dough expan
a type of microscopic fungus that people mix into bread dough so the dough expands and becomes light; brewers and winemakers also add it to fruit or grain liquids so the natural sugar changes into alcohol.
Romi added dried yeast to the warm milk and sugar before mixing in the flour.
dried yeast (common form)
The bread did not rise well because the yeast was too old to work.
yeast + rise / too old to work
Beatriz bought fresh yeast from the bakery and stored it in the fridge.
Without yeast, the pizza dough would stay flat and turn out hard after baking.
A packet of dry yeast can raise four cups of flour into a soft loaf.
- leaven
more general term for any substance that makes dough rise; 'leaven' can also be used figuratively, while 'yeast' is mainly literal and concrete
- starter
a naturally fermented mixture of flour and water that contains wild yeast, used in sourdough bread; 'starter' is a specific product rather than a general type of fungus
- baking powder
a chemical leavening agent that works through acid-base reaction rather than living fungal activity; used when no fermentation flavour is wanted
文法句型
yeast + [verb]
dried/active/fresh + yeast
yeast + for + [purpose]
用法筆記
In everyday cooking, yeast usually refers to the dry or fresh product sold in packets or blocks. Active dry yeast and instant yeast are the two most common forms. All-purpose flour is often paired with yeast in standard bread recipes.
常見錯誤
2. a single-celled type of fungus that can multiply by splitting or forming buds, a
a single-celled type of fungus that can multiply by splitting or forming buds, and that causes the chemical process in which sugar changes into alcohol.
Under the microscope, Gabriel could see the round yeast cells splitting to form new ones.
yeast cells splitting (budding reproduction)
Biologists study yeast as a model because it grows fast and shares genes with people.
yeast as a model organism in research
Yuna sampled her homebrew weekly, watching the yeast turn sugar into alcohol and bubbles of gas.
Tendai's project showed yeast reproducing by budding every two hours in warm sugar water.
- fungus
much broader category that includes mushrooms and moulds; 'yeast' is one specific type of fungus
- Saccharomyces cerevisiae
the scientific name of the most common baker's and brewer's yeast; far more technical than 'yeast'
- microorganism
even broader term covering all microscopic life forms (bacteria, protozoa, etc.), not specific to yeast
文法句型
yeast + cell / strain / culture
yeast + reproduces / grows / ferments
用法筆記
This sense is mainly used in biology and microbiology. 'Yeast' in this context is an uncountable noun referring to the whole group of organisms (Saccharomycetes). When referring to individual species, writers often use 'yeasts' as a countable plural.
常見錯誤
yeast — verb
1. to undergo or cause the chemical process in which natural sugars turn into alcoh
to undergo or cause the chemical process in which natural sugars turn into alcohol, usually producing gas bubbles and froth on the surface.
The crushed grapes were left in a warm vat to yeast overnight before pressing.
rare intransitive verb use
The fruit juice yeasted overnight, and tiny bubbles rose to the surface.
The team yeasted the grape juice for three days at a steady temperature.
Once the liquid yeasts completely, the alcohol content can be checked with a simple tool.
文法句型
[liquid/food] yeasts (intransitive)
yeast + [liquid] (transitive)
用法筆記
This verb is very rare in modern English. In almost all contexts, speakers and writers use 'ferment' instead. You are unlikely to hear 'yeast' as a verb in everyday conversation.