The Science of Baking: Chocolate
From Cacao to Chocolate
Cacao trees bare fruit year around.Pods are harvested twice a year. They are cut off the trees carefully, and can grow anywhere on the tree- even on the trunk.The trees are delicate.
Once pods are harvested they are split open and 20-50 cream colored beans are scooped out and the rest is discarded.
Once the beans have been scooped out they are fermented. They are placed in large piles and covered with banana leaves or burlap for 3-6 days.
Fermentation
- Enhances flavor
- Removes some of the bitterness
- Destroys the ability to sprout
Once they are fermented, the beans are dried. They are usually sun dried. If the climate is too moist, then an artificial method is used. Farmers will turn beans often for drying, this allows them to pick over beans and remove foreign objects and inferior beans.
Drying
- Prevents spoilage
- Lowers moisture content
- Develops flavor
- Causes beans to loose nearly all their moisture and in turn their weight
Beans are packed in 130-200 lb sacks and shipped to processing plants. Once at the processing plant, the beans are stored carefully until ready for cleaning. It is important that the beans are isolated so that they don’t absorb any off odors.
Cleaning
- Brushes, air, gravity are used (never water!)
- Removes any dried pulp, pieces of pod, other extraneous materials that have not yet been removed
Roasting
- Lasts from 30 minutes to 2 hours
- Temperature is 250 degrees or higher
- Lowers moisture content
- Color develops to a rich dark brown
- The characteristic aroma of chocolate becomes evident
- Enhances flavor
After roasting the beans are cooled quickly. This allows the shell to become brittle and easy to remove. This is often done by a machine called a ‘cracker and fanner’. This process is called winnowing. Then the shells are removed from the beans. This leaves you with the ‘meat’ of the bean called nibs.
The nibs are now in small pieces and are ready for the grinding processing. Grinding is done with large stones or steel disks. This process generates heat through friction, which allows the cocoa butter to become liquid.
Grinding
- Produces chocolate liquor (which refers to liquid- not alcohol.)
- Nibs contain 53% cocoa butter
- Liquor is the purest form of chocolate
- When poured into molds and allowed to solidify, result is unsweetened or bitter chocolate.
Production of Eating Chocolate
- Liquor is put into a mixer- called a melangeur
- Various ingredients are added to produce different types of chocolate
- Once mixed, the chocolate is still gritty and harsh. The chocolate is put through a roll press that crushes the particles and gives the chocolate a finer texture.
Conching
After being refined, the chocolate is conched.
- Conching further refines the chocolate by shaking, kneading and pressing for up to 3 days (can be as little as a few hours.)
- The higher the quality of chocolate, the more conching it goes through
- This process creates a smooth texture and fluidity
- Aids in the emulsification process
- Aerates the chocolate
- Aeration helps evaporate the volatile acids
- Reduces the harshness of flavor
- And evaporates the unwanted water
Tempering
Once the conching process is finished, the chocolate is tempered.
- Tempering is a process in which the temperature of the chocolate is manipulated to allow for the proper crystallization of the cocoa butter to occur, thus allowing it to set evenly and properly
- After the tempering, the chocolate is molded, cooled, un-molded, packaged, shipped.
Cocoa Powder
Cocoa Powder Production
- Liquor is placed in hydraulic press
- Pressure is applied and the cocoa powder is pressed out of the liquor- pressed into wheels
- The leftover cocoa cake is then pulverized and sifted. This is cocoa powder.
The cocoa butter content of cocoa powder varies:
- Grocery store cocoa is about 10% or more
- Breakfast cocoa is about 22%
Cocoa Butter
Cocoa butter is unique among vegetable fats because it is solid at room temp, but melts at 89-93 degrees. It also:
- Resists oxidation and rancidity
- Can be stored for years without spoilage
- Is used for confectionery, pharmaceutical and cosmetic purposes
About Dutch Process
- Uses alkaline chemicals that neutralize some of the acids in the cocoa
- Can be done to the cocoa powder or the beans
- Dutched products have
- A better, fuller flavor
- A deeper, darker color
- Allow for more solubility
- Are preferred by many professionals
Types of Chocolate & Their Ingredients
- Dark chocolate- cocoa liquor, cocoa butter, sugar (varying amounts), vanilla and lecithin
- Milk chocolate- cocoa liquor, cocoa butter, condensed milk or DMS, vanilla and lecithin
- White chocolate- cocoa butter, sugar, condensed milk or DMS, vanilla and lecithin
- Not ‘real’ chocolate since it doesn’t contain cocoa liquor
Couverture
Couverture is bulk chocolate that is produced the same way eating chocolate is but has a higher percentage of cocoa butter. This provides:
- More fluidity
- Better shine when set
- Harder set, good snap
- Higher quality = higher price
- Used for production of:
- Confections, pralines, fine pastries, dipping, enrobing, molding and special fillings.
Coating Chocolate
Some or all of the cocoa butter is removed from the eating chocolate and is replaced with vegetable fat of some kind. This provides:
- Less fluidity
- Less quality ingredients = less expensive
- There are good and bad quality coating chocolates
- Used for the production of coating items, such as strawberries, truffles, cookies.
Melting Chocolate
Methods
- Microwave or direct method
- 20 second increments
- Or alternately, start at 1 minute, then 45 seconds, then 30 seconds, then 15 seconds. Stir each time. Do not heat above 90 degrees for dark chocolate, 88 degrees for milk, or 86 degrees for white to keep in temper
- Double boiler
- Keep an eye on the flame
- watch for excessive steam
- Oven with pilot lighting
- Great for large amounts of chocolate
- Works well overnight
- Machine method
- Top of oven- rising heat
- Use cooling screen so there is not direct heat
Melting temperature for chocolate varies from chef to chef and chocolate to chocolate.
Chocolate, in my opinion, does not need to be heated above 115 degrees. The lower the better. Dark chocolate can withstand higher temperatures.
Tempering
Tempering should be used for couverture only. The process requires that the chocolate be heated, cooled, then reheated.
Chocolate |
Heat Chocolate To: |
Then Cool Chocolate To: |
Reheat Chocolate To: |
Dark | 115 degrees | 80 degrees | 90 degrees |
Milk | 115 degrees | 78 degrees | 88 degrees |
White | 115 degrees | 76 degrees | 86 degrees |
- Chocolates are then workable from reheated temp down to dropped temp, reheat slightly if necessary.
- Test for properly tempered chocolate
- Spatula
- Paper
- Should set up in about 3 minutes
Tempering Methods
- Table method
- Marble slab
- Vaccination #1
- Shavings
- Melt 2/3 of the chocolate and add 1/3 to bring into temper
- Vaccination #2
- Shavings- stir constantly
- Resting
- Can add a chunk of chocolate to speed up process
- Microwave
- Machine
- Easiest, no fail
- Cold water bath
- Works well for white chocolate
Enemies of Chocolate
Moisture in melted chocolate
Melted chocolate that comes into contact with moisture becomes solid chocolate- it seizes. A few drops of water in melted chocolate will make for very sturdy chocolate which is good for lacy items (like chocolate cups, etc.)
If you do end up with seized chocolate, not all is lost- seized chocolate can be used for fillings or brownies.
Moisture on set chocolate
This will form droplets of simple syrup on your chocolate. Once dried, the chocolate will have white coating called ‘sugar bloom’. It will have a gritty feeling, and does not re-melt.
Excessive heat on melted chocolate
Do not heat chocolate above 120-122 degrees. If overheated, chocolate will become pasty, grainy, and will lose flavor. Depending on how grainy it is, it could be strained and used for baking, otherwise throw it away.
Excessive heat on set chocolate
This is usually due to improper storage practices. It will cause cocoa butter to melt and rise to the surface- this is called ‘fat bloom’. This is fixable- simply re-temper the chocolate.
Storage of Chocolate
- Wrap well
- Protect from:
- Light
- Strong odors
- Foreign particles
- Keep cool- 60-65 degrees is deal
- Store close to the floor since heat rises
- Moderate humidity- do not exceed 50%
- Do not store in the refrigerator
- Can be frozen, though not recommended
Texture Changes in Chocolate
These are generally caused by:- Cold
- Overheating
- Air
- Moisture
- Overuse
Ganache
Ganache consists of couverture and water based liquid. Boil the liquid and pour over small bits of chocolate. Allow to sit one minute and stir starting in the center.
Basic Proportions:
Chocolate |
Amount of Chocolate |
Amount of Liquid |
Dark | 2 parts | 1 part |
Milk | 2.5 parts | 1 part |
White | 3 parts | 1 part |
Ganache can set out of the fridge for up to 8 days, but will keep longer in the fridge.
Learn More:
- Air Pressure & Baking
- Proteins
- Carbohydrates
- Fats
- Leavening
- Milk & Cream
- Thickening Agents
- Specialty High Altitude Baking Tips
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