Bread Yeast
Useful Microbes
Making Bread with Yeast
By Rebecca Coles
Introduction
Bread is such a common food, who would expect it to be made in such a fascinating and clever way? A simple loaf contains just four main ingredients; flour (the main ingredient), warm water (the yeast prefer the water warm), salt and of course the yeast, tiny microscopic fungi that help the bread rise. Although fascinating the process is surprisingly simple; first, the flour, sugar and water is mixed together with yeast to make the bread dough, next the yeast ferments (a chemical change that results in the production of alcohol or gas) natural sugars in the dough to make alcohol and carbon dioxide bubbles. The gas is trapped in the sticky proteins in the mixture and causes it to bubble and rise, whilst the alcohol is converted to compounds which give the bread its taste as it is baked in the oven.
What Is Yeast?
Yeasts consist of only one cell and belong to the kingdom of Fungi. There are an estimated 1,500 species of yeast with the common yeast being Saccharomyces cerevisiae, used for making bread and also beer. Yeasts need sugar to grow. They divide in a process called budding.
When was this Process discovered?
Extensive research shows that Ancient Egypt was the birthplace of the bread we know today. Although now we have modern technology to assist us, the process has stayed the same. Archaeologists that were digging in Egyptian ruins discovered old grinding stones and large baking chambers, as well as drawings of 4,000 year old bakeries and breweries.
All those years ago, the bakers were using different grains to give their bread a variety of flavours. The most common grain used back then was wheat, which made good bread. To make yummier and more interesting bread, bakers made bread in animal shapes and added dried fruits, seeds, herbs and spices. Whilst baking as an art was evident from the very start, the scientific aspect of bread-making did not begin to
Making Bread with Yeast
By Rebecca Coles
Introduction
Bread is such a common food, who would expect it to be made in such a fascinating and clever way? A simple loaf contains just four main ingredients; flour (the main ingredient), warm water (the yeast prefer the water warm), salt and of course the yeast, tiny microscopic fungi that help the bread rise. Although fascinating the process is surprisingly simple; first, the flour, sugar and water is mixed together with yeast to make the bread dough, next the yeast ferments (a chemical change that results in the production of alcohol or gas) natural sugars in the dough to make alcohol and carbon dioxide bubbles. The gas is trapped in the sticky proteins in the mixture and causes it to bubble and rise, whilst the alcohol is converted to compounds which give the bread its taste as it is baked in the oven.
What Is Yeast?
Yeasts consist of only one cell and belong to the kingdom of Fungi. There are an estimated 1,500 species of yeast with the common yeast being Saccharomyces cerevisiae, used for making bread and also beer. Yeasts need sugar to grow. They divide in a process called budding.
When was this Process discovered?
Extensive research shows that Ancient Egypt was the birthplace of the bread we know today. Although now we have modern technology to assist us, the process has stayed the same. Archaeologists that were digging in Egyptian ruins discovered old grinding stones and large baking chambers, as well as drawings of 4,000 year old bakeries and breweries.
All those years ago, the bakers were using different grains to give their bread a variety of flavours. The most common grain used back then was wheat, which made good bread. To make yummier and more interesting bread, bakers made bread in animal shapes and added dried fruits, seeds, herbs and spices. Whilst baking as an art was evident from the very start, the scientific aspect of bread-making did not begin to
Bibliography: http://en.wikipedia.org/wiki/Yeast#Baking http://www.epa.gov/biotech_rule/pubs/fra/fra002.htm http://www.breadworld.com/Science.aspx http://www.exploreyeast.com/article/yeast-and-bread http://www.food-info.net/uk/qa/qa-wi8.htm