1,561 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

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 20264545

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 20268395

Butter vs. grease

We often read in a recipe where a pastry is put into a mould that, just before pouring, the mould should be buttered or greased. But what's the difference between these 2 terms?
December 1^st 20252,9305

Getting out of the fridge early

Very often when you're cooking, you need to take food or preparations out of the fridge, to use them in the recipe in progress. There's nothing tricky about this: you just take them out of the fridge and use them, usually immediately, in the recipe. But is this really a good method?
November 24^th 20251,8915

Who's making the croissants?

When you look at a bakery from the outside, you naturally think that in the bakery, the bakers make the bread, and in the laboratory, the pastry chefs make the cakes. It's very often like that, with each of these professions having quite different ways of working, but sometimes there's also one...
November 23^th 20251,719

See all posts Random post RSS feeds

Other pages you may also like

Should I believe my oven?

Can you really trust your oven? This is an important question as we are always tempted to take the temperature indicated as gospel truth and, unfortunately, this is rarely very precise. .
July 4^th 201133 K4.6

Butter doesn't make you fat, unless you eat too much of it.

Whenever I'm discussing cooking and recipes, there is one idea which comes up frequently, like this: "Oh no! But that's got butter in it" (I should add, for the sake of accuracy, that this is something I hear more frequently from women, who are almost all concerned with keeping their figure). ...
March 26^th 201246 K4.5

How to avoid lumps

You've probably come across this unpleasant phenomenon where, when you try to incorporate an ingredient (usually a solid or powder) into a preparation (usually a liquid), the mixture doesn't mix properly and you end up with little "balls" or little lumps of the solid part that refuse to mix with the...
October 9^th 202024 K4.8

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 202138 K4.5

Soup vs. potage

It's true that we're finally coming out of winter as I write these lines, and that we'll all be making, no doubt, a little less soup and potages, but even if it's out of season, it really is a simple and delicious dish, which is one of the always easy answers to "What's for dinner this (Sunday)...
April 9^th 202212 K