Chemical Leavening Basics

Michelle Briggs Kudos Blends Ltd. Cleobury Mortimer, Worcestershire, England

An Introduction to Chemical Leavening—­ History and Development

Chapter

It is difficult to pinpoint exactly when the leavening of baked goods began, but recorded evidence of leavened bread extends as far back as the ancient Egyptians and biblical times (Page, 2013a). It was not until the nineteenth century that knowledge of chemicals first influenced the development of leavening agents (Fig. 1-­1). This led to the introduction of baking powder and the first commercially produced cakes.

Fig. 1-­1. A timeline of the history and development of chemical leavening, with a focus on the 1800s. (Courtesy Kudos Blends)

1

1

Chapter 1

Early Acid and Alkali Components

An Introduction to Chemical Leavening—History and Development

Potash (potassium carbonate) is an early example of an alkaline chemical being used in bread to counteract the sourness caused by early acid components such as soured milk. In the early 1800s, development of chemical leavening agents for the market was initiated by the introduction of sodium bicarbonate. With its low price, wide availability, and high purity it is no wonder that sodium bicarbonate is still heavily relied on in the twenty-­first century. Interestingly, today it appears chemical leavening is returning to its roots, not with potash, but with potassium bicarbonate being used as a means to reduce sodium consumption.

A chemical understanding of cream of tartar and tartaric acid was attained in the late 1700s, along with small-­scale production of tartaric acid as a by-­product of wine fermentation. It was not used in baking, however, until the mid 1800s—­instead muriatic acid, known to us today as hydrochloric acid, was commonly used. Although an impractical and somewhat dangerous acid, muriatic acid was used for more than 50 years, up until the late 1850s (Page, 2013a).

Pioneering Chemists Hugh Colquhoun was an active chemist in the early 1800s, and his findings were integral to the development of chemical leavening.

Among several chemists attempting to establish alternative means to traditional fermentation in the early 1800s, Colquhoun is note­worthy because his key findings showed: • Bitter taste from fermentation can be eliminated using sodium bicarbonate.

• Evolution of CO2 from carbonates improves eating quality and identified sodium bicarbonate as an effective CO2 generator.

• Kneading dough is essential in trapping CO2.

• Carbonates combined with tartaric acid in powder form are a good source of CO2 in baked goods.

Ten years after Colquhoun’s findings, muriatic acid was still being used as an acidulant. John Whiting released a patent in 1836 on the re2

action of muriatic acid with sodium bicarbonate. This patent is the first documented evidence of an acid/alkali reaction being used in dough, with no reference to more practical and less harmful acidulants such as tartaric acid (Page, 2013b).

Chapter 1 An Introduction to Chemical Leavening—History and Development

The Discovery of Baking Powder In the early nineteenth century, evidence showed that yeast-­raised products were associated with constipation and indigestion; this was a key factor that drove research toward alternative leavening systems.

Some companies even promoted their chemically aerated products as preventatives for indigestion, which is thought to be why the digestive biscuit commonly eaten in the United Kingdom was developed and so named.

The potential health benefits of non-­yeasted products led to Alfred Bird carrying out research in Birmingham, England, in 1843. He developed what he termed “fermenting powder,” later known as baking powder. As Bird’s wife was allergic to yeast-­raised breads, he set out to develop a means of chemically raising bread. His baking powder consisted of sodium bicarbonate, tartaric acid, and cornstarch, but it was not produced commercially until some years later. For Bird this was not a business venture but a way to assist his wife, and as such, the product was never patented.

In 1845, Henry Jones of Bristol, England, invented self-­raising (or self-­rising) flour using a formulation of sodium bicarbonate, tartaric acid, and excess filler (flour). Whether this can stand as a true invention due to Bird’s development of “fermenting powder” two years earlier is debatable. However, Jones was more business driven and in 1845 patented his product. One year later Jones was granted royal patronage and was appointed “Purveyor of Patent Flour and Biscuits to Queen Victoria,” giving the product commercial success.

Individually, Bird and Jones each saw a potential niche market for chemical aeration within the military, particularly in the British Navy, so that fresh bread could always be available at sea. They both had commercial success in this area, and during the late 1800s, as baked goods became more sophisticated, the need for chemical aeration continued to grow (Page, 2013c).

3

Chapter 1

Baking Powder in the United States

An Introduction to Chemical Leavening—History and Development

While the invention of baking powder was a major asset for the bakery industry, early loss of CO2 during processing was still an issue.

More control of the CO2 gas release was needed, which resulted in research being carried out by Eben N. Horsford, a Harvard University professor and lecturer, and Justin von Liebig, a German chemist and former lecturer for Horsford. In 1856, Horsford obtained a patent for the manufacture of powdered monocalcium phosphate (MCP). The Rumford Chemical Works was opened, and by 1859 baking powder production began with “Horsford’s Bread Preparation.” It was advertised as a healthy and nutritious baking powder and contained sodium bi­ carbonate and MCP wrapped in individual paper packages. Cornstarch was later added to allow the ingredients to be blended together; this blend was sold as “Rumford Yeast Powder,” which was later known as “Rumford Baking Powder.” During the 1950s Hulman & Co., the founders of Clabber Girl, bought the Rumford brand, and it is still produced

by Clabber Girl today (Van Wazer, 1961).

Baking Powder in Germany During the 1860s, Ludwig Marquart and Carl Zimmer were informed of von Liebig’s experiments with potassium bicarbonate and so called “acidic phosphate of lime.” Although they believed that professional bakers would not willingly use these materials in place of yeast, they attempted to interest military and naval authorities, including industrial large-­scale bakeries. In 1869 baking powder production began in Germany: Marquart sold his products in the north and Zimmer in the south, with close competition between them. Neither was successful, however, with Zimmer pulling out of the market in 1870 and Marquart following in 1872. Marquart sold the business to his sons who decided not to pursue the venture.

Nearly 20 years later, in 1890, pharmacist Dr. August Oetker bought the baking powder formulation from one of Marquart’s sons, and by 1893 he was selling baking powder marketed toward cakes rather than bread. Success followed, and the Dr. Oetker brand of baking powder is still available worldwide today (Jones, 1993).

4

Chapter 1 An Introduction to Chemical Leavening—History and Development

Fig. 1-2. A timeline of the introduction of food phosphates to the bakery industry, from the late 1800s to the present day (Bailey, 1940; Brose et al, 1996; Horsford, 1856; Knox and Schlaeger, 1939). (Courtesy Kudos Blends)

Chemical Leavening in the Present Day In 2017, sodium bicarbonate and the food phosphates developed more than a century ago by these early chemists are still extensively used in both industrial and domestic bakeries. This book will take an in-­depth look into the individual elements that make up a baking powder and how they are fundamental to the end product.

Although there has been little progression in the fundamental chemistry behind chemical leavening since the 1800s, developments have been seen with the phosphates in particular, as shown in Figure 1-­2. In the twenty-­first century we have come to a crossroads. Will we continue to improve upon this longstanding chemistry, or will health trends be the driver for innovative research?

REFERENCES Bailey, L. H. 1940. Development and Use of Baking Powder and Baking Chemicals. U.S. Department of Agriculture, Circular No. 138.

U.S. Government Printing office, Washington, DC. Brose, E., Becker, G., and Bouchain, W. 1996.History. Page 8 in: Chemical Leavening Agents, pg. 8. Chemische Fabrik, Budenheim, Germany.

Horsford, E. N. 1856. Improvement in pulverulent acid for use in the preparation of soda-­powders, farinaceous food, and for other purposes. U.S. patent 14,772.

5

Chapter 1 An Introduction to Chemical Leavening—History and Development

Jones, P. R. 1993. Justus von Liebig, Eben Horsford and the development of the baking powder industry. Ambix 40(2):69-­73.

Knox, W. H., and Schlaeger, J. R. (assignor to Victor Chemical Works). 1939. Heat treated monocalcium phosphate. U.S. patent 2,160,232.

Page, F. G. 2013a. Baking powder and self-­rising flour in nineteenth-­ century Britain: The carbon dioxide aerations of Henry Jones and Alfred Bird. Bull. Hist. Chem. 38(2):141-­142.

Page, F. G. 2013b. Baking powder and self-­rising flour in nineteenth-­ century Britain: The carbon dioxide aerations of Henry Jones and Alfred Bird. Bull. Hist. Chem. 38(2):143-­145.

Page, F. G. 2013c. Baking powder and self-­rising flour in nineteenth-­ century Britain: The carbon dioxide aerations of Henry Jones and Alfred Bird. Bull. Hist. Chem. 38(2):147-­150.

Van Wazer, J. R. 1961. Food and dentifrice applications. Pages 1601-­ 1603 in: Phosphorus and Its compounds. Vol. 2, Technology, Biological Functions, and Applications. Interscience Publishers, New York.

Author Biography Michelle Briggs works in technical sales at Kudos Blends. With more than 10 years of experience in the baking industry, combined with a B.S. (Honors) degree in science from De Montfort University in Leicester, Michelle has a thorough and detailed knowledge of baking powders and bakery processes. At Kudos Blends, Michelle oversees all of the technical enquiries relating to raising agents and uses her wealth of knowledge to train and present seminars on raising agent technology to customers and audiences across the globe. Michelle’s current focus is to raise awareness of how, by improving the nutritional profile of their products, bakery manufacturers can play a vital role in improving health on a population level.

6