Bread Making Course
Lesson 2
What is Flour
Flour is a powder made by grinding raw grains, roots, beans, nuts, seeds, or bones. Flours are used to make many different foods. Cereal flour is the main ingredient of bread, which is a staple food for most cultures. Wheat flour is one of the most important ingredients in Oceanic, European, South American, North American, Middle Eastern, North Indian and North African cultures, and is the defining ingredient in their styles of breads and pastries. Corn flour has been important in Mesoamerican cuisine since ancient times and remains a staple in the Americas. Rye flour is a constituent of bread in central Europe.
What is Organic Flour
Flour bleaching agent is the agent added to fresh milled grains to whiten the flour by removing the yellow colour pigment called xanthophyll. It whitens the flour and this flour is used in baking industry
What is Organic Flour
Organic flour is milled from pesticide-free grain and grown in soil only fertilized by natural substances. The flour is not artificially processed or chemically ripened.
What is Gluten
Gluten is a protein that builds the network that keeps your dough together. It binds the starch almost like a web of elastic bands that runs through the bread, allowing the starch to gelatinise and stay in place. It works a bit like a balloon, capturing the carbon dioxide that comes off the microbes as they ferment the sugars in the flour, i.e. one with more protein content. You don’t need very strong flour to bake great sourdough. Generally, I work with flour with about 11–13.5% protein. Occasionally I use a higher gluten flour to support lower gluten ones and use it to blend.
Different Kinds of Fermitation
What is Fermentation
The flour you use also dictates, to a large extent, the speed of fermentation. Flour contains amylase, an enzyme that breaks down carbohydrates into sugars that the yeasts can access. A flour’s enzyme levels will depend on where in the world it was grown. British flours tend to have high levels of naturally occurring enzymes because they are grown in a maritime environment. This results in high levels of enzyme activity, which means that dough ferments more quickly, yeasts are more active and more carbon dioxide is produced, making the bread more bouncy and voluptuous. You will sometimes find flours that have had enzymes added to them – flours from the Uk, for example, tend to have more naturally occurring enzymes so millers making it easier to get the liveliness and activity needed.
What Are the 3 Different Types of Fermentation?
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Lactic acid fermentation. Yeast strains and bacteria convert starches or sugars into lactic acid, requiring no heat in preparation. These anaerobic chemical reactions, pyruvic acid uses nicotinamide adenine dinucleotide + hydrogen (NADH) to form lactic acid and NAD+. (Lactic acid fermentation also occurs in human muscle cells. During strenuous activity, muscles can expend adenosine triphosphate (ATP) faster than oxygen can be supplied to muscle cells, resulting in lactic acid buildup and sore muscles. In this scenario, glycolysis, which breaks down a glucose molecule into two pyruvate molecules and doesn’t use oxygen, produces ATP.) Lactic acid bacteria are vital to producing and preserving inexpensive, wholesome foods, which is especially important in feeding impoverished populations. This method makes sauerkraut, pickles, kimchi, yogurt, and sourdough bread.
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Ethanol fermentation/alcohol fermentation. Yeasts break pyruvate molecules—the output of the metabolism of glucose (C6H12O6) known as glycolysis—in starches or sugars down into alcohol and carbon dioxide molecules. Alcoholic fermentation produces wine and beer.
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Acetic acid fermentation. Starches and sugars from grains and fruit ferment into sour tasting vinegar and condiments. Examples include apple cider vinegar, wine vinegar, and kombucha.
The best way to store Flour
Flour must be kept cool and dry. All flours, even white flour, have a limited shelf life. Millers recommend that flours be stored for no more than six months. The main change that occurs is the oxidation of oils when flour is exposed to air. The result of this is rancid off flavours. During hot weather, store flour in the refrigerator.
Flour should be stored, covered, in a cool and dry area. This prevents the flour from absorbing moisture and odours and from attracting insects and rodents. Freezing flour for 48 hours before it is stored will kill any weevil or insect eggs already in the flour. It is better not to mix new flour with old if you are not using the flour regularly.
Do not store flour near soap powder, onions or other foods and products with strong odours.
If freezer space is available, flour can be repackaged in airtight, moisture-proof containers, labelled and placed in the freezer at 0 degrees F. If flour is stored like this, it will keep well for several years.
Keep whole wheat flour in the refrigerator the year around. Natural oils cause this flour to turn rancid quickly at room temperature.
Throw away flour if it smells terrible, changes colour, or is invested with weevils.
Flour is always readily available so it should only be brought in quantities that will last a maximum of two to three months.
Put a bay leaf in the flour canister to help protect against insect infections. Bay leaves are natural insect repellents.
Water
Sourdough bakers often overlook the importance of water. We can talk for hours about the nuances of the flour, but actually water is key to the success of the loaf too. How much to add, when to add it and the temperature all contribute significantly to the finished loaf. The most important thing to remember, though, is that you should NOT add all the water at once when you mix.
One of the key processes of a beautiful open crumb sourdough is developing gluten when mixing, but if you add in all the water at once you will get a soup-like consistency. You have to hold back some of the water. As a rule of thumb I mix almost all my white dough at 70% hydration (so 700g of water to 1kg of flour). The remaining water is set to one side and added gradually once the gluten has been developed. This is a technique called bassinage. The exception to this rule is with wholegrain, which requires more like 78–85% hydration. I apologise for being vague. This is the bit where you will need to use your judgement. It is why I recommend baking the classic loaf first, so you have a point of reference.
Why do we use salt
One of the important functions of salt is its ability to improve the taste and flavour of all the foods in which it is used. Salt is one ingredient that makes bread taste so good. Without salt in the dough batch, the resulting bread would be flat and insipid.
You should never completely avoid using salt in sourdough – it has significant gluten-strengthening properties, provides the base for the flavours and helps to control the speed of fermentation. If your doctor has advised you to cut down on salt, you can reduce the amount used by half but to compensate please add miso, soy or a good rehydrated finely chopped seaweed, such as dulse. This will give you more minerals and compensate for the lack of flavour, plus the extra minerals will go someway to help strengthen the dough. (As a guide I use about 5–7 grams of dry seaweed which is then rehydrated to replace half the salt.
Leavening agent
In cooking, a leaven, often called a leavening agent, is any one of a number of substances used in doughs and batters that cause a foaming action that lightens and softens the mixture. An alternative or supplement to leavening agents is mechanical action by which air is incorporated.
I have made a list of Leavening agent that we use in day to day baking.
How Does Fermentation Work?
To master fermentation, you need to understand the science behind the chemical process.
Microorganisms survive using carbohydrates (sugars, such as glucose) for energy and fuel.
Organic chemicals like adenosine triphosphate (ATP) deliver that energy to every part of a cell when needed.
Microbes generate ATP using respiration. Aerobic respiration, which requires oxygen, is the most efficient way to do that. Aerobic respiration begins with glycolysis, where glucose is converted into pyruvic acid. When there’s enough oxygen present, aerobic respiration occurs.
Fermentation is similar to anaerobic respiration—the kind that takes place when there isn’t enough oxygen present. However, fermentation leads to the production of different organic
molecules like lactic acid, which also leads to ATP, unlike respiration, which uses pyruvic acid.
Depending upon environmental conditions, individual cells and microbes have the ability to switch between the two different modes of energy production.
Organisms commonly obtain energy anaerobically through fermentation, but some systems use sulfate as the final electron acceptor in the electron transport chain.
What is yeast?
Yeasts are single-celled microorganisms that predate humans by...hundreds of millions of years. There are more than 1,500 species of yeast, but the species we're concerned with today is saccharomyces cerevisiae, derived from Latinized Greek meaning "sugar-fungus." This group of yeasts includes strains of baker's yeast and brewer's yeast, responsible for producing our favorite carb-heavy treats: bread and alcohol. They work by feeding on sugars and converting that food into carbon dioxide (and alcohol, given enough time), giving your baked goods that soft, airy structure you love and your beer that bubbly nature.
What are the different types of baker's yeast?
There are three main types of commercially produced baker's yeast: active dry, instant, and fresh. All of them will work to leaven doughs in any given yeasted baking recipe, but each has slightly different properties, and, for the more discerning palate, varying flavors.
Active dry yeast
Live yeast is partially dehydrated, rendered inert, and ground into granules. You'll often find this sold in ¼-oz. packets or a 4-oz. tinted glass jar in the baking aisle. These dormant yeast cells can be stored at room temperature for several months until their expiration date but are heat-sensitive and potency can vary. Be sure to store it away from super warm areas up until the moment you're ready to bake—active dry yeast will begin to die once exposed to temperatures higher than 120°F. To extend shelf life, store sealed packets in an airtight bag in the freezer to keep the yeast in a more secure state of suspension.
Before being added to your recipe, active dry yeast should be dissolved in lukewarm (between 100°F and 110°F) water or milk, to ensure its activity level. If your yeast mixture does not increase in size and become foamy in 10 to 20 minutes, your packet was likely DOA and no longer viable. This likelihood is not unthinkable: The manufacturing process for active dry yeast can kill up to 25% of yeast cells.
Instant yeast
Also known as "bread machine yeast" and "RapidRise," instant yeast is more shelf-stable and tends to be more reliably and consistently active than active dry yeast (talk about misleading names!). The most popular brand of instant yeast among pro-bakers is SAF-Instant, which is sold in a 16-oz. package. Instant yeast has finer, smaller grains than active dry yeast. This increased surface area allows for a faster rehydration process, and it can be used in recipes without blooming the yeast in a liquid beforehand. (Nonetheless, I still prefer to bloom instant yeast to ensure even distribution in the dough.)
When used in substitution, ¾ teaspoon of instant yeast is equivalent to 1 teaspoon of active dry due to its increased potency and shorter fermentation time. Instant yeast can be stored in the freezer in an airtight container for up to 2 years.
Fresh yeast
Also known as "cake yeast" and "compressed yeast," fresh yeast comes in big blocks or smaller, individually packaged cubes and can be found in the refrigerated aisle near dairy and eggs. It is the only form of commercial yeast that isn't dehydrated: a solid but crumbly concoction of water and yeast, its rubbery texture is halfway between paste and modeling clay. Due to its high moisture content, this form of yeast is the least shelf-stable, requiring refrigeration and lasting only about two weeks under ideal conditions. If kept in too humid or unclean a container, white tufts of mold can develop within a week and the yeast is no longer safe to use. For longer storage, divide your fresh yeast into individual portions and wrap each piece tightly with plastic wrap before placing in your freezer for up to a year.
Some bakers prefer to use fresh yeast in sweeter recipes, such as donuts, for its more vibrantly yeasty perfume. When used in substitution, 1 oz. of fresh yeast is equivalent to 0.4 oz. of active dry yeast or 0.33 oz. of instant yeast. To substitute for a ¼-oz. packet of active dry yeast, use about ⅔ oz. of cake yeast. To substitute for a ¼-oz. packet of instant yeast, use about ¾ oz. of cake yeast.
what is kombucha
Kombucha is a fermented drink made from sweetened tea and a specific culture known as a scoby. Scoby stands for 'symbiotic culture of bacteria and yeasts'. The bacteria and yeasts convert the sugar into ethanol and acetic acid. The acetic acid is what gives kombucha its distinctive sour taste.
How do you make a sourdough starter with kombucha?
To your sourdough starter jar, add 1/2 cup of brown rice flour and 1/2 cup filtered water or 1/2 cup plain kombucha. You may want to add kombucha in the beginning until your starter is established. Stir until thoroughly mixed and cover with the tight-weave dishcloth.
Sourdough starter
Ingredients
Day 1
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175ml/6fl oz skimmed milk
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75ml/5 tbsp fresh, live, full-fat, plain yoghurt
Day 2
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120g/4oz strong white flour
Day 3
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150g/5½oz strong white flour
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150ml/5½fl oz water
Day 4
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180g/6oz strong white flour
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100ml/3½fl oz water
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40ml/3 tbsp milk
Day 5
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150g/5½oz strong white flour
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150ml/5½fl oz water
Method
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On day one, heat the milk in a saucepan over a gentle heat. Place the yoghurt into a bowl and stir in the warmed milk. Cover and leave in a warm place for 12-24 hours until thickened. Stir in any liquids that may have separated.
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On day two, stir the strong white flour into the yoghurt, incorporating evenly. Cover and leave at room temperature (about 20C) for two days. The mixture should be full of bubbles and smell pleasantly sour.
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On day four, add the measured flour to the starter with the water and the milk. Cover and leave at warm room temperature for 12-24 hours.
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On day five the starter should be quite active now and be full of little bubbles. Remove half of the starter and discard. Add the flour and the water to the remaining starter and mix thoroughly. Cover and leave at warm room temperature for 24 hours.
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On day six the starter should be ready to use. You can keep the starter at room temperature, but you will need to feed it daily. Combine equal parts of the starter, water and flour and mix thoroughly. You may have to discard some of the starter so that you do not end up with too much. Keep covered and use as needed.
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If baking less often, keep the starter covered in the fridge, feeding it once every five days or so by mixing equal parts of starter, flour and water.
Tips
You can freeze some of your sourdough starter if needed, as a back-up in case you need to start again. You can also keep it in the fridge if you bake less often.