jimtrue.com : school : CUL115 : Week 1: Pre-ferments

Posted by Jim True on January 13, 2010 11:46 PM. Last Updated January 13, 2010 11:46 PM

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Week 1: Pre-ferments

Yeast

• A single celled microorganism of the fungi family that requires specific living conditions to thrive
1. Moisture
2. Oxygen
3. Food
• These are all needed in the appropriate temperature in order to reproduce and create alcoholic fermentation (the conversion of sugars to alcohol and carbon dioxide)
• There are over 100 species that convert sugar into alcohol and carbon dioxide. There is only one strain that is commercially sold today: Saccharomyces cerevisiae (SACKARO-MY-SEE-SERA-WE-SEE-AY).
1. Instant Yeast: Can be added directly into dry ingredients without rehydrating, except for croissants, danish and bagels. It is moistened in 4-5x's it's weight in water and the temperature of the water is 85-100ºF
2. Compressed (Cake) Yeast: Is a Mixture of Yeast and Starch with a moisture content of 70%. It is softened int 2x's it's weight in water, and the water temperature should be 100ºF. Fresh yeast should not have a strong odor to it, it should be dry to the touch and have a creamy color to it. Fresh yeast can be stored in the refrigerator for up to 3 weeks.
3. Active Dry Yeast: All the moisture has been removed by hot air, left dormant. Add enough water to moisten and rehydrate in water of 100-110ºF. It can be stored up to 2 months in a cool dry place. To substitute 1 t of rapid rise yeast, add 25% more active yeast to the recipe.

Fermentation

• Fermentation in bread baking refers to the conversion by yeast of sugars into carbon dioxide, alcohol, heat and organic acids
• There are FIVE Stages of Fermentation:
1. Buik (Primary) Fermentation that starts the moment the mixer is turned off
2. Bench Rest: After dividing and preshaping, the second fermentation begins with the bench rest
3. Proof: Once the loaves are shaped, the third stage is known as the final proof or fermentation begins
4. Oven Spring: The final phase begins once the loaves are loaded into the oven; this is known as oven spring.
• The optimal phase of fermentation is when a pre-ferment is used.
• The hours of yeast activity which occurs as the pre-ferment ripens

Desired Dough Temperature

• The Desired Dough Temperature is important to a bread baker for uniformity of the bread and its flavor and flow of the bread production throughout the bakery. The longer or slower bread dough is allowed to ferment, the more time the flavor has to develop.
• Bread Baker's have only so much time in their schedule to bake bread and only so much room in the ovens to fit the bread. Starting bread fermentation at specific temperatures gives the baker time for other bread production
• Straight Dough:
• Take the desired dough temperature from the recipe and multiply by 3 (ex. 76 degree final DDT x 3 = 228)
• Subtract the flour temperature (ex 228-72 degrees = 156)
• Subtract the room temperature (ex 156 - 68 = 88)
• Subtract the friction factor of the mixer: This is 26 for the 20 quart and 30 quart mixers. (ex 88 - 26 = 62)
• Water Temperature is 62º F. This is the only variable that we DO have control over
• Pre-Ferments:
• Take the desired dough temperature from the recipe and multiply by 4 (ex. 76 degree final DDT x 4 = 304)
• Subtract the flour temperature (ex 304-72 degrees = 232)
• Subtract the room temperature (ex 232 - 68 = 164)
• Subtract the pre-ferment temperature (ex 164 - 70 = 94)
• Subtract the friction factor of the mixer. (ex 94 - 26 = 68)
• Water Temperature for your dough should be 68º F.

Pre-Ferments

• A pre-ferment is a portion of dough's overall ingredients that are mixed and allowed to ferment before being added to a final dough mix.
• Pre-Ferments come with many names: Poolish, Biga, Pâte Fermentée and Old Dough to name a few
• When using a pre-ferment, a few things should happen:
1. The dough's structure is strengthened
2. The bread develops a superior flavor
3. The keeping quality improves
4. The overall production time is reduced

Scoring

• What does this mean and why do we do it?
• By Scoring bread dough, you are intentionally creating a week section on the surface of the loaf in order to encourage controlled expansion of the bread. Left unscored, the bread will have difficulty reaching its full volume. The bread will burst out at another weak area on the loaf, giving a distorted and tortured look to the loaf
• Some bread has very traditional scoring like a baguette, while others are scored with numerous designs. Bakeries sometimes have a signature score for each bread type and/or sometimes its the baker who does. There are no real rules to scoring, so be creative
• Some bread loaves may be weak from over rising or due to the nature of the flour, so scoring the dough lightly is required. Other bread loaves offer great strength and can handle deeper cuts that will open beautifully in the oven during the bake
• Tools for Scoring
• There are many tools in the bakeshop that can be used for scoring bread. The most traditional tool used is a lame. A Lame is a straight edge razor with a handle on it that can hold the razor straight or curved.
• Substitute a serrated knife for a lame
• Scissors can make a beautiful design
• A rolling pin makes great indentations
• a docker will make uniform holes. If a docker is not available use wooden toothpicks or a skewer

Baking with your Five Senses

1. Hearing: As the dough spins in the mixer, the sound changes. If the dough makes a slapping noise in the bowl, then you know you have achieved the correct hydration level
2. Touch: Touching the dough during the mixing, kneading and fermentation allows the baker to understand the variety of changes that occur during the dough's development. The dough may be examined by a gentle tugging and squeezing.
3. Smelling: A baker should understand what a good starter smells like. It is ripe and ready to go or too weak? The smell of the fermentation aroma is important throughout the dough's development. As the bread bakes in the oven, the smell changes
4. Seeing: The eyes guide at every stage. Sometimes a formula may state "allow the bread dough to rise for 1 1/2 hours", your eyes may see that the dough has already risen twice its size in one hour. Our eyes see a pattern to follow with the lame as the dough is cut into sections
5. Tasting: Tasting everything from starters to doughs to finished products, will help the baker understand each stage or process. A baker should taste for a well-balanced product.

Gluten

• The combination of proteins that contribute to dough elasticity, extensibility and strength. Gluten is not found in flour alone, add water and manipulate the dough to create gluten.
1. Gliadin: Found in wheat flour and rye flour. Provides dough with extensibility (the ability of the dough to stretch without tearing)
2. Glutenin: Found in wheat flour and very little in rye flour. It helps develop dough structure and the elastic quality of the dough (the resistance to stretching).

Disclaimer: These are MY notes taken from classroom lectures while I'm in the classroom. While I'm perfectly happy to share my notes with my classmates and I know I take very good notes, you should still make every effort to attend the class and TAKE YOUR OWN NOTES. I will not transcribe everything the instructor says in the classroom, and I will NEVER post pre-exam reviews. My notes will not replace the value of actually attending class and taking your own class notes.I also cannot attest to their accuracy, other than they are what was provided in the lecture; you should not reference my notes as "expert opionion" by any means, and if you notice an error or omission, please do me the favor of e-mailing me with the correction and I will re-post my notes. End of Disclaimer.