Chorleywood Bread Process
Encyclopedia
The Chorleywood bread process is an industrial process used to lower the cost of bread production. The CBP, or no time method, was developed in 1961 by the British Baking Industries Research Association based at Chorleywood
, and is now used to make 80% of the UK's bread
. Compared to the older bulk fermentation process, the CBP is able to use lower protein wheat, and produces bread at a much faster rate, with the disadvantage that the bread requires extra processing to enhance the flavour. The process had an important impact in the United Kingdom, as at the time, few domestic wheat varieties were of sufficient quality to make high quality bread products, and it therefore permitted a much greater proportion of low-protein domestic wheat to be used in the grist
. Whereas this innovation benefitted UK agriculture in finding new, higher value markets for its products, some authors claim CBP products have reduced nutritional value.
, and intense mechanical working by high-speed mixers to incorporate air into the dough. The last requirement means that the CBP cannot be reproduced in a domestic kitchen. Solid fat is necessary to prevent the risen loaf from collapsing — in traditional methods, this structure is provided by the gluten produced by higher-protein flour.
Flour, water, yeast, salt, fat, a chemical oxidiser such as ascorbic acid, and minor ingredients such as emulsifiers and enzymes are mechanically mixed for about three minutes. The high shear mixing generates high temperatures in the dough, which is cooled using a cooling jacket on the mixer, air pressure in the mixer headspace can be controlled so that gas bubbles of the desired size and number can be produced. Typical operating regimes are pressure followed by vacuum and atmospheric followed by vacuum.
The dough is cut into individual pieces and allowed to "recover" for 5-8 minutes. Each piece of dough is then shaped further, placed four to a tin and moved to the humidity- and temperature-controlled proofing chamber, where it sits for about 45-50 minutes. It is now ready to be baked. Baking takes 20-25 minutes at 400°F (about 200°C) and then the loaves go to the cooler, where, about two hours later, they are sliced, packaged and ready for despatch.
The CBP is only minimally used in the United States
, largely due to the "strong" wheats grown in North America that do not require such intensive mixing. Bread made with these high quality flours can be made with other mixing types such as bar and spiral mixers.
In many countries, enzymes and several other "improvers" are not required to be listed on ingredient labels, as they are considered to be consumed in the baking process. ).
There is a small group of campaigners, under the name Doh Boy, who criticize the Chorleywood bread process. They wish to "raise awareness" of the disadvantages of this method.
Chorleywood
Chorleywood is a village and civil parish in the Three Rivers district of Hertfordshire in the United Kingdom. It had a population of 6,814 people at the 2001 census. The parish of Chorleywood as a whole has a population of 10,775. The town lies in the far south west of Hertfordshire, on the...
, and is now used to make 80% of the UK's bread
Bread
Bread is a staple food prepared by cooking a dough of flour and water and often additional ingredients. Doughs are usually baked, but in some cuisines breads are steamed , fried , or baked on an unoiled frying pan . It may be leavened or unleavened...
. Compared to the older bulk fermentation process, the CBP is able to use lower protein wheat, and produces bread at a much faster rate, with the disadvantage that the bread requires extra processing to enhance the flavour. The process had an important impact in the United Kingdom, as at the time, few domestic wheat varieties were of sufficient quality to make high quality bread products, and it therefore permitted a much greater proportion of low-protein domestic wheat to be used in the grist
Grist
Grist is grain that has been separated from its chaff in preparation for grinding. It can also mean grain that has been ground at a grist mill. Its etymology derives from the verb grind....
. Whereas this innovation benefitted UK agriculture in finding new, higher value markets for its products, some authors claim CBP products have reduced nutritional value.
The process
The aim of the Chorleywood bread process is to use cheaper, lower-protein wheats and to reduce processing time, the system being able to produce a loaf of bread from flour to sliced-and-packaged form in about three and a half hours. This is achieved through the use of chemical improvers, solid vegetable fat, higher quantities of yeastYeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...
, and intense mechanical working by high-speed mixers to incorporate air into the dough. The last requirement means that the CBP cannot be reproduced in a domestic kitchen. Solid fat is necessary to prevent the risen loaf from collapsing — in traditional methods, this structure is provided by the gluten produced by higher-protein flour.
Flour, water, yeast, salt, fat, a chemical oxidiser such as ascorbic acid, and minor ingredients such as emulsifiers and enzymes are mechanically mixed for about three minutes. The high shear mixing generates high temperatures in the dough, which is cooled using a cooling jacket on the mixer, air pressure in the mixer headspace can be controlled so that gas bubbles of the desired size and number can be produced. Typical operating regimes are pressure followed by vacuum and atmospheric followed by vacuum.
The dough is cut into individual pieces and allowed to "recover" for 5-8 minutes. Each piece of dough is then shaped further, placed four to a tin and moved to the humidity- and temperature-controlled proofing chamber, where it sits for about 45-50 minutes. It is now ready to be baked. Baking takes 20-25 minutes at 400°F (about 200°C) and then the loaves go to the cooler, where, about two hours later, they are sliced, packaged and ready for despatch.
Worldwide
It is used in over 80 percent of factory-produced bread in the United Kingdom, Australia, New Zealand and India. Even many "speciality" and organic breads are produced this way. The CBP has been used in 28 countries worldwide, and has made inroads in France, Germany and Spain, with plans to introduce the system to China.The CBP is only minimally used in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, largely due to the "strong" wheats grown in North America that do not require such intensive mixing. Bread made with these high quality flours can be made with other mixing types such as bar and spiral mixers.
Change in wheat
Since the introduction of the Chorleywood bread process, many UK domestic wheat varieties have been improved. Flour suitable for traditional high quality pan bread can now be sourced in the United Kingdom, although such flour attracts a significant milling premium. The CBP's use of cheaper wheat, to produce bread acceptable to the bulk of UK customers, means that the process is still used for 80% of UK bread production.Bread additives
CBP processes may include the following additives, but these additives are not limited to CBP:- Fat in the form of palm fat or oils, to soften the dough and bread and create a finer cell structure.
- SaltSaltIn chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...
allows yeast to grow while reducing competitive bacterial growth, and affects the flavour. - Esters of monoglycerides and diglycerides act as emulsifiers and anti-stalingStalingStaling, or "going stale", is a chemical and physical process in bread and other foods that reduces their palatability. Stale bread is dry and leathery.-Mechanism and effects:...
agents. - Calcium propionateCalcium propionateCalcium propanoate or calcium propionate has the formula Ca2. It is the calcium salt of propanoic acid.-Uses:As a food additive, it is listed as E number 282 in the Codex Alimentarius. Calcium propanoate is used as a preservative in a wide variety of products, including but not limited to bread,...
inhibits mould. - Enzymatically active soy flour contains lipoxygenase enzyme that creates whiter crumb.
- AzodicarbonamideAzodicarbonamideAzodicarbonamide, or azobisformamide, is a synthetic chemical with the molecular formula C2H4O2N4. It is a yellow to orange red, odorless, crystalline powder. As a food additive, it is known by the E number E927.-Use as a food additive:...
is a flour oxidizer, banned in EU, Canada, Japan, Australia and New Zealand, but permitted in the US. - Ascorbic acid is the most common dough oxidising agent used in the EU, mainly for wholemeal and whole grain breads.
- GlutenGlutenGluten is a protein composite found in foods processed from wheat and related grain species, including barley and rye...
provides texture. Added gluten augments the low gluten levels of cheap low-protein wheat. - Starch enzymes and protein enzymes are used to rapidly break down wheat starches to sugars to feed the yeast and to "mellow" the gluten to allow for reduced mechanical mixing times. Enzymes are also engineered to survive baking temperatures and great variations in pHPHIn chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
to impart antistaling and softening qualities to the finished products.
In many countries, enzymes and several other "improvers" are not required to be listed on ingredient labels, as they are considered to be consumed in the baking process. ).
Criticism
In the book Not on the Label: What Really Goes Into the Food on Your Plate, Felicity Lawrence claims that the industrial scale of the Chorleywood Bread Process comes at a nutritional cost, requiring larger amounts of salt and yeast than traditional bread recipes. However, salt levels in all types of bread have been reduced in recent years. Andrew Whitley in his book Bread Matters: The State of Modern Bread and a Definitive Guide to Baking Your Own criticises the CBP for the inferior flavour and texture of the bread made in this way.There is a small group of campaigners, under the name Doh Boy, who criticize the Chorleywood bread process. They wish to "raise awareness" of the disadvantages of this method.
Other processes
- Batch Mixing Bread Process, method currently used in US.
- Continuous Mixing Bread Process, popularized with Wonder BreadWonder BreadWonder Bread is the name of three North American brands of white bread: One produced by George Weston Bakeries in Canada, another by Hostess Brands in the United States, and the third by Grupo Bimbo in Mexico.- United States :...
in the 1970s - Aerated Bread CompanyAerated Bread CompanyThe Aerated Bread Company Ltd was founded in the United Kingdom in 1862 by Dr. John Dauglish. Its aim was to mass produce healthy, additive-free breads using a new bread leavening technology invented by the company's founder...
An English bread company which operated from in 1862 to the 1980s, using carbon dioxide instead yeast