The Bread Leavening Agents And The Sourdough Starter
One of the most important parts of the bread making is the leavening process using the bread leavening agents. This reaction is an important part of giving bread its quality, in texture and flavour. It is important to understand how this process works. The same technique is generally used in most cultures all around the world. In some places such as the middle east unleavened bread will also be served.
The Bread Leavening Process
To follow are some steps to help you appreciate the importance of bread leavening agents including yeast and tips on how to begin using yeast.
On Bread Leavening Without Yeast
Leavening means to put gas into the dough during or before the baking process to achieve a more chewable, lighter bread. Most bread eaten in the UK is leavened, however unleavened breads are out there. Leavening is a basic technique that uses the gas producing chemicals.
There are several ways to leaven bread without yeast, using other bread leavening agents. The two most common methods are: 1. The method of using baking powder or a self-raising flour that may include baking powder. 2. This method involves adding an acidic ingredient such as baking soda with buttermilk. The reaction of the baking soda and the acid with create the gas. This type of leavening is used when making soda breads and for a fast bake bread. This method is used more in the making of sweet breads or muffins.
On Bread Leavening With Yeast
The many bread leavening agents include yeast. Which is used in the leavening of a range of breads and is a single cell fungus. The species of yeast used in bread leavening is called Saccharomyces cerevisiae, this is the same type as used in the brewing of alcohol. In the reaction the yeast will ferment carbohydrates in the flour and any sugar. This will create the carbon dioxide.
More On Yeast And Bread Leavening Agents
The sourdough and the baker’s yeast method of making bread follow a similar process. The baking liquid, such as water is combined with the salt, flour and the leavening ingredient. Other ingredients like fruits, nuts and seeds are not essential to bake bread, however these add flavour and texture. Once the dough has been mixed it is allowed to rise at least once. Bakers will often knock the dough back once risen and let it rise again. The dough is formed into loaves in the required style and baked in the oven.
Another process of making breads is using the straight dough or the direct dough method. In this case all of the ingredients will be added in a single step and allowed to rise and then baked in the oven.
The starter method for making dough is another option. This is when the water, flour and raising agent are mixed at least one day before baking. This allows the dough to ferment. All the other ingredients will then be added and the rest of this method is similar to the straight dough process. The finished product will be more flavourful with a better texture.
Bread can also be leavened by steam expanding very quickly within the bread. This is a basic method, however it can be unpredictable. The most common type of bread that uses this method is the popover. Also steam leavening can be done using most leavening agents including: sourdough, egg snow, yeast and baking soda. Although this method is unpredictable due to the steam only being created once the bread is baked.
Bread – Sourdough and Leavening
The range of leaving agents used in baking all have their own properties. This results in different characteristics of the end product for each leavening agent used. The taste in sour dough is not produced by the yeast it is the lactobacillus ( a non–spore forming bacteria) the yeast lives in association with the lactobacillus. The lactobacillus feeds on the left over products of yeast fermentation. This makes the part that turns sour by the excretion of lactic acid. Also this will protect everything from spoiling.
The baker’s yeast that is used in the baking of bread, is a specific strain of yeast. This is not naturally sour because of the absence of the lactobacillus and needs to go through the process to form a sourdough starter. All breads were sourdough up to the 19th century, until the process of rising through microbes was fully understood. As soon as this development was made by scientist’s yeast was taken on by bakers all over the world.
Sourdough Bread Essentials
Sourdough bread is made using a sourdough starter. The sourdough starter is produced by the Lactobacillus and yeast this is where the lactobacilli and yeast live and is similar to a pancake mixture. A sourdough starter can be managed continuously by removing a part of the starter to be used and adding fresh flour and water back into the mix. Starters can be kept for long periods of time. Some starters have been passed down from generation to generation is baking families. Due to the sourdough starters growing potential it is possible to buy small pieces from specialist suppliers and growing them.
A traditional method for the culture of sourdough in bread making families. Is to have the sourdough prepared and keeping a piece back to use for the following week. If baking once a week then a small piece of sourdough will be kept back each week and grown for the next week. The starter will be saved from the previous week and mixed with the new ingredients and left to rise.
Salt Risen Bread – Bacteria
Salt risen bread uses a leavening method that does not use yeast. This process is not as accurate as using yeast as a leavening agent and needs close attention. This style of bread making will produce a cheese-like flavour and a smooth texture.
Fats and Preparation
There are a broad range of bread preparation methods, and this will vary from culture to culture. The finished product will change depending on the preparation methods used. Also the body, crust and the texture will vary with each different method or ingredient used. And some bakers will have their own methods of producing original types of bread.
The gluten development within the bread can change depending on the fats used. Fats including vegetable oils, butter and lard will coat the single protein strands that help hold the structure together. By using too much fat in a bread dough recipe then the proteins structures may separate.