Learning Objective: Understand the process of tabliering or hand tempering
Tabliering (hand tempering or mush method)
Tempering lays the foundation for success in any chocolate process. It ensures that the cocoa butter fatty acids are in the V form (see "About the V-Form" lecture in this Module) and that the chocolate will harden correctly with shine and color. This is the preferred method used by experienced professionals because, if done properly, the temper of the chocolate will be perfectly crystallized.
Chocolatiers and chocolate makers have used the tabliering method to temper chocolates since "eating" chocolate was first produced. By literally using their hands to feel when the chocolate is ready to use, professionals over the centuries have produced exquisite products. Now, most chocolatiers and chocolate makers rely on tempering machines for most of their chocolate products but some still dip certain items by hand for a more traditional look. Also, some artisan chocolatiers use this method to introduce the first seed into their holding kettles or enrobers.
Note from instructor: As you look at some of the tempering videos and follow links to other sites on tempering, you'll find that there are variations in both technique and recommended temperatures used in the tempering process. There is no one magic formula for tempering chocolate. We present a general method that works for most chocolates in most environments. But you need to experiment and practice to find the technique and temperatures that work for each particular chocolate you temper. There are so many variables that come into play:
Chocolate ingredients. Each chocolate has different proportions of ingredients: cocoa solids, cocoa butter, sugar, vanilla, lecithin, etc. These all impact the temperatures needed to create a perfect temper. Manufacturers have tempering specifications for each of their chocolates. To achieve a perfect temper, you need to know what those specifications are so you can use them as your guideline.
Air temperature and humidity. If it's warmer or cooler in the room during your practice session, you'll have to adjust for the room temperature in how you temper – the amount of seed needed in the seeding method; reduction of the temperature by making the cool water bath or marble slab a little colder; keeping the warm water bath stable when you try to maintain the temper. Too much humidity or too dry a climate also can effect temper.
Your thermometer. As you're checking very minuscule temperature changes from one degree to the next, you need to make sure your equipment is used properly and functioning correctly. You'll want to take the temperature after stirring the chocolate mass thoroughly (not when it has been sitting for a while as such a thick mass will develop hot and cool spots).
Agitation. You must continually stir the mass throughout the process. If you leave it on the marble slab without stirring, you run the risk of the part of the mass that is up against the cool marble solidifying. If you're heating or tempering from a bowl, the chocolate up against the hot bottom or sides of the bowl will fall out of temper. Again, since we're talking differences of only one or two degrees, you have to be careful with the process.Heat. Whether you're using a bain-marie or the microwave, heat is the enemy. Be careful with your temperatures. Burnt chocolate clumps together in a dry, grainy mess – this usually happens at the bottom or around the sides of your pan in a bain-marie or in the hot spot in the microwave. You can probably still re-use the chocolate in a baking recipe, such as in a cake or brownie, but it cannot be used for ganache or tempering for molding or dipping.
Over-tempered or over-seeded chocolate. As you stir the chocolate mass over time, you create more V-form crystals which makes the chocolate mass thicker, until it is hard to work with – even though it's still in temper. To combat this, you need to melt some of the excess V-form crystals, either by adding warm chocolate at 115°F (47°C) or by heating the edges of the chocolate mass with a hair dryer or over hot water. Make sure you thoroughly mix the warmed chocolate into the mass. You need to have the seeding chocolate hot, but be careful not to raise the temperature of the whole mass too much, which will throw it out of temper. Testing for the temper periodically is always a good idea.
Too thick a coating. Chocolate prefers to cool evenly, so an even, thin coating will be resistant to bloom. If your chocolate is too cool and you end up with a thick coating, the outside cools first and looks fine as it sets up, but the inside is still warm, which may produce bloom as it cools slowly.
Shocking the chocolate. This can occur when the center you are enrobing is too cold or has moisture in it. It can also occur from keeping the enrobed centers into the fridge too long where, again, cold and moisture can form. Shocking will produce a dull finish and possible sugar bloom.
While the following process may seem primitive, it's the basis for developing a "feel" for well-tempered chocolate and truly being able to call yourself a chocolatier or chocolate maker. Even when using a tempering machine, processes can sometimes go wrong. Having the skill to visually and tactually know that the chocolate is tempered distinguishes the professional.
IMPORTANT NOTE: Chocolate is expensive so try your best to work cleanly, even with this messy technique. Save all the chocolate "residue" on your marble, counter, utensils and bowls. As long as it's clean, without bits of other ingredients or moisture, you can use it again for tempering or ganache.
The tabliering process
The tabliering process consists of reproducing by hand the tempering steps we discussed in the lecture on tempering machines. In hand tempering, the chocolatier will not use a thermometer to measure when a specific temperature is reached, but determine how the temperature of the chocolate relates to his or her body temperature. Temperatures have been included as a reference only.
Note: The ideal temperature of the workshop should be approximately 68°F (20°C). If you're working in a very hot and humid climate and can't get your room temperature that low, it's very important that you make sure your marble or granite surface is cool. A bag of ice on the surface for a few minutes will bring it down. Just make sure to wipe up all moisture before starting your tempering. You may need to reapply the ice between tempering sessions.
I borrowed the inspiration for the following tempering diagrams from Chef Givre's explanation of tempering technology. We'll use this key for the following diagrams:
Step 1: To melt all fatty acid crystals, heat to 104 - 115°F (40 - 46°C).
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Heating the chocolate mass to at least a minimum of 104°F (40°C) ensures that all the crystals in the cocoa butter are melted. Different chocolates have different melting points, so it's always good to use the manufacturer's suggested temperatures for melting and tempering. |
Chopped chocolate hunks or pistoles are melted using either the microwave or double boiler. For details refer to the lecture earlier in the program curriculum Table of Contents entitled: Lecture: Working with Chocolate.
Temperature check: Using a thermometer, check that the temperature of the melted chocolate is now between 104° - 115° F (40° - 46° C). Milk and white chocolates should only be heated to the lowest range. That being said, don't make the mistake of UNDER-heating your chocolate. If you experience problems with tempering, try heating to the higher temperatures in the range.
Let's talk sbout thermometers
We've found that the best thermometer for the tempering process is a probe thermometer. It allows you to easily and accurately take the temperature of your chocolate mass on the marble slab, as well as in a bowl. These thermometers are a box design with digital readout attached to a wire and probe. They can cost anywhere from $20+ to $200+ – the more expensive, the more accurate and durable it is. There are many out there – just do a search on "cooking thermometer+probe." Note: With the model in this photo, you would remove the pan clip on the probe when testing a chocolate mass on your slab.
Don't want the mess of a probe thermometer? There's another solution but it isn't as accurate as the probe. My experience at Valrhona introduced me to the use of infrared thermometers in tempering and making ganache. The thermometer Chef Givre used was a gun model, like the one shown below. While it only takes the surface temperature of the chocolate or ganache mass, if you make sure to stir the mass thoroughly before taking the temperature, you'll have a pretty accurate read of the temperature of the mass. This method doesn't work if you leave too much time between the stirring and the time you take the temperature, but if you're careful to stir then shoot immediately, it works fine. No mess or having to clean the thermometer after reading the temperature as you would with the stick-type thermometer. As these are not cheap (I've seen prices from $69US and much higher), I didn't include them as part of the supplies for the program. If your budget allows, you'll definitely want this very helpful piece of equipment. There are many, many different kinds on the market, so I suggest you do an Internet search on "infrared thermometers." For example, Raytek has a variety of different models, as does Bon Jour Products.
Gun-type Infrared Thermometer
Step 2: To form seed crystals, cool to between 79 - 80°F (26 - 27°C).
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As you cool and agitate the chocolate mass, it forms both stable and unstable crystals during the process. The crystals that we want are the yellow stable Form V crystals, but this will also create unstable crystals, which we'll deal with in the next step. |
Approximately 30 - 40 per cent of the melted chocolate is ladled onto a cool marble slab.
The remaining chocolate is kept warm by either reheating in the microwave occasionally or leaving it in the bain-marie, but with the heat source for the hot water turned off. This warm reserved chocolate will be used later in the tempering process to keep the tempered chocolate mass from becoming too cool and solidifying.
Using either a hand or pallet knife, the chocolate mass on the marble slab is stirred in a circular motion pulling the chocolate from around the edge of the puddle into the center. This process ensures that the chocolate mass on the marble slab is in constant motion as it cools rapidly.
For success with this technique, don't UNDER-agitate: keep the mass moving rapidly throughout the tempering process. Stirring is very important, as chocolate is a poor conductor of heat, so you need to keep those crystals moving to maintain temperature and keep them from solidifying!
Chef Givre at Valrhona uses a pallet knife to move the chocolate
during the tempering process and an offset spatula to keep the pallet knife clean.
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Temper check: After a few minutes, there will be a very recognizable thickening and cooling that can be felt with the fingers.
Step 3: Melt any unwanted crystals and hold temper
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We then start raising the temperature to melt all the unstable crystals. These unstable crystals have a lower melting temperature than the stable crystal, so if we bring the temperature up above 84°F (29°C), we'll melt all the unstable crystals and have only the stable crystals left in the mass for a perfect temper. |
- Dark chocolate between 88° - 90°F (31° - 32°C)
- Milk or white chocolate between 84° - 86°F (29° - 30°C)
At this point the chocolatier has two choices:
- Heat the tempered chocolate mass to the working temperature above by the addition of the warm liquid chocolate from the reserved chocolate using a ladle. This method allows the chocolatier to work from the marble slab to produce the required chocolate product.
This on-slab method works best for hand-enrobing nuts or fruits and the production of chocolate decorations such as curls or cutouts where the chocolate is spread on plastic or parchment. To retain the temper of the chocolate mass on the marble slab, the mass will need to be continuously warmed by additions of the warm liquid chocolate from the reserved chocolate over the course of the production.
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- Transfer the mass back into a clean, warm bowl or back into your chocolate covered used bowl to save extra clean-up. An easy method for the transfer, if you have a stand alone marble slab, is to pull the marble slab to the end of your counter or table so that 2 inches (6 cm) of the slab protrudes over the counter. Hold the bowl under the edge of the marble slab and scrape the chocolate across the slab, over the edge and into the bowl. Add warm chocolate from the reserved bowl if the temperature of your tempered chocolate drops under 79°F (26°C) during the transfer process but again, make sure not to raise the temperature of your mass over 90°F (32°C).
This bowl method works best for hand-dipping or molding where higher temperatures and less viscosity (i.e., more fluidity) are needed.
When you don't have a warming or tempering machine that holds your mass of tempered chocolate at a constant temperature automatically, there are many different methods you can use to retain that working temperature – see the options below. Remember, it only takes a little bit of heat to raise the temperature of the mass a degree or two.
- Adding a small amount of the warm reserved chocolate
- Reheating the mass in the bowl carefully in the microwave
- Placing the bowl back on the bain-marie over the hot water for a few seconds
- Using a heat gun or hair dryer (used for only that purpose) to heat the surface of the chocolate while stirring (be very, very careful that you don't burn the surface of the chocolate mass).
- Wrapping the bowl with a heating pad (experiment with the temperature to make sure you know exactly how much heat your pad produces)
With all the above heating methods, make sure that you agitate the chocolate mass by stirring to incorporate the warmed part of the mass into the rest of the chocolate as you check the increasing temperature.
About "Residence Time" - this term is used in the industry to denote the additional time you need to continue to stir the chocolate mass once it has reached the desired temperature in order to ensure you have V-form crystals incorporated all through the mass of chocolate. Remember chocolate is a very dense substance and it takes time for those V-form crystals to propagate throughout the mass. The why is explained this way by our QA Online Tutor, Kerry Beal, "To grow crystals you need time (because crystals grow on crystals) you need to be at the right temperature to encourage the growth of the crystals and you need to agitate to bring crystals in contact with areas that have no crystals so that crystals can grow on crystals." The bottom line is to continue agitating the chocolate mass for 2 - 5 minutes (more time for a larger volume of chocolate - less time for a smaller volume of chocolate) to make sure you have a good "crop" of V-form crystals throughout.
Temper check: Chocolatiers traditionally test with a small dab of chocolate on the upper lip – it should feel cool and just slightly below body temperature. To retain the temper, check often and raise or lower the heat of the hot water source.
Ecole Chocolat Note: Our Online Tutor gives this advice: "When we temper the chocolate in our shop, I am often amazed at the difference in the quality of the temper after that chocolate is cooled to 29°C and then the final bit of heat is added to bring it back up to 32°C. The three-degree difference can be striking and a crucial step in achieving the best results." Which is why you need a thermometer accurate at minute temperature changes.
Don't forget to keep the tempered chocolate agitated throughout the time you're working with it, otherwise it will begin to solidify.
IMPORTANT NOTE: When you have finished tempering your chocolate, never use it for molding or enrobing purposes unless you have done a temper test. This is done by taking a small smear of your tempered chocolate, either on a piece of parchment/acetate or a utensil such as a spoon, knife or spatula. Let the chocolate harden. If perfectly tempered, the chocolate should solidify within minutes in a 68°F (20°C) workshop. Check that the hardening is present at the same rate throughout the smear. This will give you a good indication that the crystallization you created while tempering is uniform. Look for gloss and snap.
Here are two other videos on tempering so you can see how other chocolatiers do the same technique:
Resources and references
Callebaut offers some good information about tempering on their site along with a lot of videos in the Tutorials link on their CallebautTV page. Go to http://www.callebaut.com You will have to register and create a login to access Callebaut TV and the Tutorials.
Making Handmade Chocolates with Jenn Stone contains some good photos of the tempering process.
Videos on tempering:
Cacao Barry online demonstrations are very good. Don't be put off by the French in the intro – the demonstrations themselves are in the language you select when you register. These professionally made videos are free, but you have to register as they are collecting contacts for their sales efforts.
Callebaut TV Again, these videos are free, but you have to register.
Ghirardelli Chocolate has short videos on working with chocolate, including tempering.
Keylink has a number of technique videos that you may find helpful.
You think that you are alone in struggling with perfect tempering? The following article shows you tempering is an industry issue:
Ultrachoc project seeks consistent chocolate qualityFebruary 2013 Ultrachoc.eu Chocolate quality is highly dependent on a stage of the manufacturing process known as tempering. Tempering is critical for reducing processing failures and ensuring a quality end product. In simple terms, tempering involves mixing and cooling the liquid chocolate under controlled conditions to ensure that the fat phase in the chocolate composed mainly of cocoa butter, crystallises in its most desirable form, i.e. form V. Incorrect tempering makes the chocolate become dull, susceptible to fat bloom, soft in texture as well as difficult to de-mould. Thus, the physical and textural properties of chocolate are influenced by the microstructure formed during crystallization of liquid fat. The control of the molecular structure and polymorphic form of this fat is therefore particularly important in the manufacture of chocolate. To this end, small, medium and large enterprises of the chocolate industry, as well as research centres from 8 different European countries will participate in the EU-funded project ULTRACHOC that aims to develop a low cost ultrasound-based system capable of controlling by real-time monitoring the tempering process during chocolate manufacture. The project Kick-Off meeting will take place on the 18th and 19th of February in Castelldefels, Spain, in IRIS project coordinator headquarters. Cocoa butter as key factor As SFC may change during manufacturing and storage, it is important to be able to measure this parameter to control the ingredients and manufacturing conditions for achieving optimum product quality. Traditional methods of SFC determination are slow, irreproducible, require additional chemicals and are based on sampling such as dilatometry. While dilatometry is an extremely precise technique, it is somewhat laborious and has been replaced in many applications by low resolution Nuclear Magnetic Resonance (NMR). While the NMR method is rapid and easy to use, it is poorly sensitive to low concentrations of solid fat and is expensive. An on-line sensor capable of measuring the SFC in the chocolate melt would allow automated control of the tempering process and would be of great value to manufacturers. Unfortunately, neither of these approved methods, which are based on sampling technique, is entirely appropriate for on-line application, thereby leaving a clear technological gap. In view of this technological gap, the ULTRACHOC project will build on the promising results of past laboratory scale research that has revealed the strong sensitivity of cocoa butter shear crystallisation process to the Ultrasound Doppler-based velocity profile (UVP) and pressure drop (PD) technique, thereby practically providing a basis for an on-line temper meter. To this end, this project will aim to carry out further laboratory trials with the UVP-PD and Ultrasound attenuation (USA) technique, UVPPD + USA, in order to define the parameters required for the industrial system that can be used as a tool in commercial chocolate manufacturing facilities. Ultrasound has long been a popular technique that is finding increasing use in the food industry for both the analyses (ultrasound of high frequency) and modification of food products (ultrasound of low frequency or high power ultrasound). Two possible methods for controlling the tempering process will be explored during the project based on the use of ultrasound: as a technology to control the fat crystal size during tempering (high power ultrasound), and ultrasound of low energy for the development of an on-line sensor capable of measuring the SFC (UVPPD and USA). The project coordinator, Dr Adriana Delgado, highlights that the combination of the two methods in a system that is readily integrated in chocolate tempering machines will represent a breakthrough for the EU chocolate industry. Towards the end of the project, the system will be installed at the sites of the different end-user SMEs in the consortium, SKELLIGS in Ireland, and CARLA in the Czech Republic, and an additional test site will be set up at one of the European facilities of either NESTLE or VALOR. As for the role of the three research performers, SIK will carry out laboratory trials using high power ultrasound to tailor and control the fat crystal size, while ETH Zurich will perform laboratory trials with ultrasound of high frequency using ultrasound Doppler based velocity profile (UVP), pressure drop (PD) and ultrasound attenuation techniques (USA) to measure the solid fat content (SFC) on-line. Finally, IRIS will scale up the technology based on these laboratory results and build a precompetitive ULTRACHOC system able to measure in real time the SFC content of the chocolate and changes in the chocolate melt during tempering, and to assist and improve the crystallization process during tempering by using ultrasound technology. IRIS R&D, a Barcelona-based company dedicated to advanced engineering and R&D solutions, will coordinate the international project from its branch office in Dublin, Irleand, whereby 9 other companies and research centres will also participate: Carla Spol Sro (Czech Republic), Seaclaidi Na Sceilge Teoranta (Ireland), Aktive Arc Sarl (Switzerland), Ubertone Sas (France), Prefamac Nv (Belgium), Nestec York Ltd (United Kingdom), Chocolates Valor SA (Spain), SIK-Institute foer Livsmedel Och Bioteknik AB (Sweden), and Eidgenoessische Technische Hochschule Zurich of Switzerland. The consortium of ULTRACHOC consists in 5 SMEs and 2 large companies, and 3 research centres. The two-year project will strength Europe’s reputation as a consistent supplier of superior quality chocolate.
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