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Have you ever wondered why the bread in the supermarket is always so slippery, the interior is so uniform, and it won't get hard for a long time, but the home-made steamed buns have big irregular holes in them, and they are hard after a day?

Behind this is actually amazing technology and hard work.

(photo: wikimedia) it starts with the fact that the British can't afford to eat bread.

Half a century ago, bread was a very precious food for the British people, mainly because British flour could not make delicious bread. at that time, common white bread mainly depended on wheat flour imported from the United States and Canada.

A kind of ancient British bread: Scottish Bannock bread (beremeal bannock), which is made of British-made barley. Because British-made wheat is low in gluten, the texture of the bread is hard. Does it seem to give you an appetite? (photo Source: wikimedia) Why is this happening?

According to the British Baking Industry Research Association (BBIRA), the bread making process is nothing more than these steps: mixing noodles, hair noodles, baking, cooling. The process does not sound surprising, but surprisingly, it is this mediocre craftsmanship that makes English bread expensive.

The thing is, handmade bread needs to be kneaded and then fermented with yeast. This process is not only time-consuming and laborious, but also requires a high protein content of gluten (also known as gluten), that is, flour.

Gluten, also known as gluten, is the protein in wheat (mainly glutenin) (photo source: wikimedia) anyone who has made Western-style pastry knows that Western-style cakes that need to wrap bubbles like bread need high-gluten flour, because the inflated form is formed by an elastic network made of glutenin that wraps the edges of bubbles like balloons.

(photo Source: hippopx) however, British flour is of poor quality and low in protein, so there is no way to make high-quality white bread. After Britain had a North American colony, British white bread was revived by imported flour from the United States and Canada. By 1939, 70% of Britain's grain was imported, from which you could see the quality of English flour.

During World War II, in order to save limited space for cross-sea freight, British Prime Minister Winston Churchill called on British people to eat less bread made from imported flour and more "National Loaf" made from local flour. This kind of bread is not very gray, and it looks and tastes bad.

During World War II, Britain encouraged its citizens to eat "national bread" made from home-made low-gluten flour (photo: see watermark). The British have not stopped trying to make less bad bread from low-gluten flour.

Finally, in 1961, the British Bakery Industry Research Association (British Baking Industries Research Association) in Jolywood, England invented a new bread-making technology, and it has since dominated supermarket bread shelves around the world. This new process is called Chorleywood bread process, or CBP for short.

Compared with traditional handmade bread, CBP bread has the advantage of being short and fast and does not pick flour, so it is also called "no-time method".

(photo: wikimedia) while traditional handmade bread takes 4-10 hours to make, today's CBP assembly line can convert flour into packaged sliced bread in about an hour.

Let's see where the supermarket bread comes from.

First of all, CBP technology through violent mechanical kneading, it only takes less than 4 minutes to complete the dough mixing process.

CBP technology using mechanical noodles (photo source: Inside The Factory How Our Favourite Foods Are Made) such a short time and out of the noodles can be good?

Contrary to our imagination, the quality of noodles has little to do with time, but it has something to do with the degree of beating of the dough, that is, the energy input in the process of dough.

A large number of food industry studies have found that the greater the input energy of the mixer, the bigger the dough, the finer the internal bubbles and the softer the bread. The principle behind this phenomenon is not yet fully understood, but it is generally thought to be related to the oxidation process, the process by which gluten is netted.

After mixing the noodles, the traditional bread still needs to give the yeast several hours to make the noodles, but with the help of double yeast, the CBP dough making process is compressed to about 1 hour.

Dough is the process of forming a net of gluten under the squeeze of bubbles, which come from carbon dioxide produced by yeast (photo source: Inside The Factory How Our Favourite Foods Are Made). Of course, most importantly, CBP can use low-gluten flour. Federation of Bakers Limited, the world's leading food producer, claims that CBP has greatly reduced bread-making time through the use of high-energy and noodle machines, as well as allowing UK-grown wheat to be used to make bread.

In order to make the bread always have an industrial feel of softness and evenness, CBP has also introduced technology that handicrafts dare not imagine-high pressure and vacuum.

CBP bread with good noodles (photo source: Inside The Factory How Our Favourite Foods Are Made) you should know that the softness of bread and cake lies in the dense bubbles inside. To create a soft and uniform dough, CBP injects the dough with high-pressure gas and uses a vacuum to control the size of the bubbles.

At the beginning of the dough, the CBP assembly line will inject extra air into the dough, resulting in a large number of bubble cores in the dough.

The pressure inside the CBP and the cylinder can be adjusted, see the lower right corner (photo source: Baker Perkins Tweedy) at the end of stirring, the air pressure in the cylinder will approach the vacuum, when the bubble core expands and bulges into uniform and dense bubbles, the volume of the dough becomes larger, so the bread will become delicate and soft.

(photo Source: Baker Perkins Tweedy) according to the world-renowned culinary institute Blue Ribbon International (Le Cordon Bleu), when the bread mass produced in the supermarket is cut, you can see that the inside of the bread is relatively tight and dry, and there are no stomata, this is because the supermarket bread is produced by large machines, using the Chorleywood bread production method.

(photo source: wikimedia) however, assembly line work alone does not change the physical properties of low-gluten flour that tend to collapse. In order to make the low-gluten dough swell, CBP will inevitably add two additives that traditional bread does not need: oxidants and emulsifiers.

The function of the oxidant is to let the gluten form as many grids as possible, supporting the shape of the bread. In the past, potassium bromate was used in industrial bread, but later it was found to cause cancer, so vitamin C is now the most commonly used oxidant in CBP.

Vitamin C added to supermarket bread (sometimes labeled "ascorbic acid") is an oxidant during CBP processing (photo source: see watermark) you may wonder, vitamin C is not antioxidant, how does it become an oxidant?

In the absence of air, vitamin C is indeed reductive. But under the action of a large amount of air, vitamin C can oxidize gluten and quickly form a network. It is vitamin C that allows the dough to withstand the violent processing of industrialization, preventing the dough from collapsing into a pile of mud after being hammered.

The function of industrial noodle (photo source: Baker Perkins Tweedy) emulsifier is to extend the shelf life and keep the bread from collapsing during baking. At present, the emulsifier used in CBP bread is stearin, that is, fatty acids with a higher melting point. Cheap stearin is usually hydrogenated vegetable oil, which is why you see this ingredient in industrial bread with a long shelf life.

Diglyceride is an emulsifier used in CBP bread making. (photo source: see watermark) however, the above process does not fully explain why supermarket sliced bread can be kept for a long time without being hard.

Take the counterexample of CBP bread, the baguette made by Britain's old enemy France, which is one of the few varieties of bread in the world that still insists on not using CBP.

Baguette (photo source: hippopx) anyone who has eaten a baguette knows that the newly baked baguette can be used for self-defense the next day. Elisa Karkle, a food scientist at Kansas State University, explains this: handmade bread hardens the next day because starch tends to become crystalline again, a process called retrogradation.

Starch in dough (top), starch in fresh bread (middle) and recycled starch (bottom) (photo source: biologyreader.com) this is why handmade bread, as well as the "carbon bombs" such as steamed buns, twistbread and rice that we usually eat, will be very hard after being kept for a long time.

(photo Source: wikimedia) Why isn't supermarket bread recycled?

This is another major innovation of modern CBP process: amylase.

Karkle said that the food industry has been looking for the right amylase. Food researchers have tried amylase from bacteria, but the bacterial amylase is so powerful that it can easily cause the whole bread to be digested.

The commonly used anti-retrogradation additive is malt amylase (Maltogenic amylase enzyme), which has just the right effect and can break the "legs" of amylose, which is easy to regenerate.

The "α-amylase" in the additive belongs to malt amylase, whose function is to prevent bread from harden. (photo source: see watermark) it is after such a meal that the CBP process increases the softness of sliced bread by 40% and doubles the shelf life.

(photo: wikimedia) compared with traditional handmade bread, CBP bread is cheaper, more durable and more stable in quality, but it also has many disadvantages.

The first disadvantage is that the bread loses its flavor. Blue Ribbon International points out that the fermentation process of CBP bread is shortened as much as possible, thus losing the aroma brought by fermentation.

Second, the fermentation process can not only bring special aroma, but also break down gluten. The lack of fully fermented CBP bread is also thought to be associated with a surge in intestinal diseases. For example, John Warner, a researcher at Imperial College, found that the number of people allergic to bread in the UK has increased significantly over the past 50 years.

(photo source: publicdomainpictures) as early as 2004, the National Institutes of Health (NIH) pointed out that although intestinal disease used to be a rare disease in the United States, accounting for only 1 / 2500 of the population, 1% of Americans (about 3 million people) suffer from intestinal disease, and this number may be underestimated, a phenomenon related to gluten in pasta. Because many patients disappear their intestinal symptoms after fasting foods containing gluten.

In short, industrial bread feeds more people but is not so delicious, while delicious bread cannot feed most people. Delicious food probably conforms to the law of conservation.

Pure nature will eventually be hard on you, only technology and hard work will always be gentle to you.

Reference:

Https://docs.qq.com/doc/DVE13anRiUmFsaXFi

This article is from the official Wechat account: bring Science Home (ID:steamforkids), author: everything.

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