1,575 easy and fully explained recipes, with +66K photos and 78 videos

This site uses only a few technical cookies necessary for its operation. By continuing to browse, you accept their use.
To find out more...

Raising (or leavening) agents

When we want to make a dough or batter rise when baking, either in patisserie or bread-making, we need to use a raising agent or leavening agent, one of which is called leaven.

In the context of baking, a raising agent is simply what "makes something rise". It is a substance which, when added to the dough or batter makes it swell up by creating thousands of tiny bubbles of carbon dioxide within it.

As there are 2 kinds of yeast, 2 kinds of leaven and baking powder as well, this can be confusing, so here is a summary of the different types and how they act.

58 K 4.8/5 (18 reviews)

Keywords for this post:Yeast Sourdough Bread Bakery Pastry Baking powder

Last modified on: June 16^th 2021

For this post: Comment Follow Ask me a question Send to a friend

Raising (or leavening) agents

Baker's Yeast

This is the yeast used by bakers to make bread, brioches, etc. It is basically the same kind that brewers use to make beer, so it is sometimes also known as brewer's yeast.

Yeast is a living organism, a microscopic fungus, called saccaromycès cerevisae, which reacts with the sugars in flour to form carbon dioxide. It is this fermentation process that makes the dough rise. Yeast is available in 2 forms:

Fresh yeast

baker's yeast

This is the classic baker's yeast which is normally sold as a small, beige-coloured block. It should be kept in the fridge and not for too long.

Dried yeast

dried yeast

This is exactly the same yeast, but completely dehydrated. It comes as a beige powder and keeps very well.

Baking powder

baking powder

This white powder is a mixture of bicarbonate of soda and cream of tartar. It reacts on contact with the water in the dough or batter to form the carbon dioxide which makes it rise. There is no fermentation.

Baking powder is used mostly for cakes, scones, etc.

Leaven

Leaven is a natural raising agent, like yeast. It is made from a mixture of water and flour that begins to ferment when exposed to the naturel yeasts present in the air.
It is a living substance and reacts with the sugars in flour to form carbon dioxide by fermentation, which makes the dough rise. Two different forms can be made:

Liquid leaven

liquid leaven

This is a leaven made with equal parts of water and flour. As the name suggests, it is liquid, rather like pancake batter.

Stiff leaven

stiff leaven

This is a leaven made with one part water to two parts flour. It has a consistency similar to bread dough.

Whether the leaven is liquid or stiff it makes little difference in its use, but a lot in the taste of the bread obtained.

It is worth noting in passing that when making leavened bread, it is usual to combine a large amount of leaven with a little yeast. This improves the bread's appearance especially the crust.

Summary

We can say that yeast and leaven work by fermentation, whereas baking powder uses a chemical reaction.

Lasts posts

The other use for bowl scraper

Your kitchen or bakery utensils may include a horn (left) or a pastry cutter (right). These practical utensils are normally used to scoop the contents of a bowl or salad bowl - the horn - or to cut dough - the pastry cutter. But they also have another, very practical use - let's see what it is.
May 9^th 2026922

The strange foam of potatoes in milk

As you may have already noticed, when you cook potatoes in milk, especially in small pieces (slices or cubes) for a gratin for example, a surprisingly abundant white foam forms on the surface. Where does it come from?
April 26^th 20261,052

A little leftover butter

Very often when you're making a cake, your recipe will tell you to melt some butter and mix it into the batter - a classic for cookies, cakes, moelleux and the like. And every time you do this, you'll have to butter the baking tin to prevent the dough from sticking during baking. Naturally,...
April 16^th 20261,1445

A tablet holder

Perhaps you too cook by consulting your recipe on a tablet or phone, and putting it down on your worktop? It's practical, but not the best solution. Here's a look at how you can make an inexpensive, almost universal stand.
March 14^th 20261,8805

Pre-calibrated pastry dough

When making pie dough (shortbread, shortcrust, sweet...), it's always a good idea to make a lot at once, and then divide it into pieces, which you can freeze. I've already pointed out the mistake not to make, which is to form a ball before freezing. It's difficult to roll out afterwards because...
March 9^th 20261,6585

See all posts Random post RSS feeds

Other pages you may also like

The march forward

When professionals get to work in their kitchen, lab or bakery, they are (if they are conscientious) very sensitive to hygiene and cleanliness. It is impossible for a good baker for example to do a day's work without regularly cleaning the table where he or she works, and it is even more...
June 30^th 202121 K5

Tranché, dissociated, failed, in short... missed!

When preparing a sauce or a cream, there's always a (small) risk that the creamy preparation you're working on will suddenly separate into two parts of different textures: a liquid part, for example, and a more or less solid part, or even become lumpy. It's terribly frustrating, but we'll see...
June 19^th 202314 K5

The secret of cooking until "done"

This is a real chef's skill: being able to look at a fish fillet cooking and say, "Stop – that's enough, it's cooked". I always admire this ability to see at a glance if something is done. It is what sets the professionals apart from us mere amateurs. And it's true that how fish is cooked is...
November 26^th 201221 K4.4

The so-called "nervous" meats

You've probably heard this before, we're talking about "nervous" meat, or meat with nerves, to describe what is indicated by the blue arrow on the left. This is a piece of beef, and what we call a nerve is not a nerve, it is in fact collagen (chemists sometimes call it a "collagen sink"), a...
April 16^th 202139 K4.5

Incise some meats before cooking

Have you ever had this rather unpleasant phenomenon: you grill a meat, a pork chop or a veal cutlet for example, and during cooking it becomes completely deformed? It takes a very strange shape, a bit difficult to describe, a sort of cone around the central area of the meat, which also hinders...
June 19^th 202113 K4.9