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Tempering Chocolate
June 26, 2008
9:15 am
stow10
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April 20, 2008
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Hi there, I’m using a bain marie at present for tempering and I always test to see if the chocolate has “snap” at the end. However, I have noticed that sometimes with the finished results, the milk chocolate has streaks in it and during storage, small speckles have appeared in clusters. Am I right in thinking therefore, that this is a sign of preliminary over heating and would this affect shelf life?

June 26, 2008
2:50 pm
Ilana
Israel
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those aresigns of fat and sugar bloom. Which means that the chocolate wasn’t tempered well enough. How do you temper ?- be exact
It doesn’t affect the shelf life of the chocolate.

Ilana Bar-Hai www.ganache.co.il
June 27, 2008
6:49 pm
Alex Rast
Manchester, United Kingdom
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October 13, 2009
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quote:


Originally posted by stow10

Hi there, I’m using a bain marie at present for tempering and I always test to see if the chocolate has “snap” at the end. However, I have noticed that sometimes with the finished results, the milk chocolate has streaks in it and during storage, small speckles have appeared in clusters. Am I right in thinking therefore, that this is a sign of preliminary over heating and would this affect shelf life?


Certainly it means your chocolate wasn’t in perfect temper, and yes, the most probable cause IME is initial overheating during the temper. It’s also possible that you’re reheating too much in the 3rd phase. As you may know milk chocolate is more temperamental than dark, by and large, with a narrower working window as well as lower temperatures throughout. I’d spend some time to profile the temper carefully against the milk chocolate you’re using. If you’re using different milk chocolates this again could be a cause of the intermittent problems – some work fine with your existing profile while others don’t

I do have, respectively, to disagree with Ilana with regards to shelf life. Now, the shelf life in terms of *food safety* isn’t affected, that is to say you won’t get sick from eating an untempered chocolate any sooner than you would a tempered one. But from a point of view of *flavour* shelf life is not only dramatically reduced, but indeed unless the chocolate is retempered will always be worse. The reduction in shelf life also applies to later retempering, so if you have chocolate that’s fallen out of temper and been allowed to sit like that for some time (days or weeks), the flavour will be worse that what it would have been had it been retempered immediately.

Alex Rast
Alex_Rast_Alternate@hushmail.com

Alex Rast Alex_Rast_Alternate@hushmail.com
June 28, 2008
8:07 am
Ilana
Israel
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I agree that the flavour and texture is certainly affected in a negative way. I was referring to shelf life in terms of health! By the way, if the chocolate is tempered incorrectly, there may be more of a tendency for the filling to be less well encased and thus more exposed to air. This can affect shelf life interms of health, if there is a filling. What do you think Alex?

Ilana Bar-Hai www.ganache.co.il
June 28, 2008
4:21 pm
stow10
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Because I’m using less than 1kg of chocolate at present, I’m using a bain marie and a method reecommended for all types of chocolate. So I heat the water until just below boiling (no steam),with chocolate in a bowl on top (glass bowl which isn’t ideal). Then swith off, stir chocolate and leave until temperature drops to 32C. Then use. Its worked until lately when Ive taken less care with the preheating which is where I feel Ive gone wrong. So the chocolate has still had snap and been shiny but has shown signs of streaking with clusters of spots appearing after a few days. Does this still sound as though the preheating is the problem?

June 28, 2008
6:27 pm
Ilana
Israel
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tempering is a system by which time, temperature and movemeny or agitation are all necessary. You need to heat or melt the choc to a temp instructed by that particular producer as cocoa butter of different types has different needs. In gemeral for dark choc 45-49 C is good. At this point thereshould be very few crystals of any type left in the chocolate. If you keep it at this temp for at least 2 hours- all the better. Now you need to cool it down and mix. You can do this by adding callets of choc that is hard and tempered. This cools the chocolate down and adds crystals. You also need to constantly mix. I do this until the callets don’t melt any more – I keep adding callets while mixing so that when the choc is getting to working temp I am in control of the amount left that does not melt. The choc should be ready at around 31-32C but always do a test. If you feel something is not right, you can bring the temp down more to say 27-28 and then reheat to 31-32. Just waiting for it to cool will not give correct results.
Perhaps at your method, if the thermometer is not accurate you can end up with untempered choc or under temp. That is my 2 cents anyway.

Ilana Bar-Hai www.ganache.co.il
June 28, 2008
10:06 pm
Alex Rast
Manchester, United Kingdom
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stow10: Now that you’ve described it I think, as Ilana does, that the problem is more basic and related to method. As described below, simply letting chocolate to cool isn’t reliable. I think what may be missing is an idea as to why the steps in the laborious process are necessary. I’ll try explain as I understand it below.

quote:


Originally posted by Ilana

tempering is a system by which time, temperature and movemeny or agitation are all necessary. You need to heat or melt the choc to a temp instructed by that particular producer as cocoa butter of different types has different needs. In gemeral for dark choc 45-49 C is good. At this point thereshould be very few crystals of any type left in the chocolate.


The key point about tempering is, it’s all about crystallisation. Chocolate, or more specifically, cocoa butter, doesn’t have a single-phase crystallisation. Put into layman’s terms that means the shape of the crystals can vary depending on what conditions they form in. However, as it happens only one of the forms is properly stable for chocolate – that which has the highest melting point, as it turns out. What you’re trying to do with tempering is to return the chocolate, once cool, so that all of its crystals are in this phase. The complication is, that if any crystals are present in a different phase, they can act as nuclei that promote further crystallisation in the wrong phase, “breaking” the temper.

The first step, as above, is the melting. You want to be absolutely sure that every last crystal in the chocolate is melted, so that there can be no possibility a rogue crystal in the wrong phase might cause large parts of it to solidify in the wrong phase. While in theory chocolate should come pre-tempered, and since the right phase is the highest one, merely melting it at all should be sufficient, in practice you can’t count on that. So you heat it to high enough temperature that it’s definitely absolutely melted.

quote:


If you keep it at this temp for at least 2 hours- all the better. Now you need to cool it down and mix.


Step 2 is to cool it down to the point where crystals do start to form. Again, in theory you could do this simply by cooling to the solidification temperature of the right crystal phase (31C), but in practice the temperature of the next-highest (wrong) phase is so close
that again, it would be virtually impossible to be that controlled with any volume of chocolate, at least using normal confectionery equipment. So what you do is cool it down to just the point where it starts to solidify. At this point, hopefully most of the crystals will be in the right phase but perhaps a few won’t. How do you resolve this problem?

quote:


You can do this by adding callets of choc that is hard and tempered. This cools the chocolate down and adds crystals.


This is one method, otherwise known as the “seeding” technique. The idea behind this approach is to introduce a concentration of crystals already in the right phase, encouraging the right crystallisation as explained above. BTW, the term “callet” is just a Callebaut term for a small round drop. Of course the seeding technique relies on you already having an additional supply of solid chocolate of the same type, which may or may not be the case. Other techniques don’t require that – with the penalty of being perhaps finickier to master initially. The basic idea is this, however: to bring the aggregate mixture into that critical temperature range where only the right phase will remain solid.

The way to look at this is as a marginal reheat of the solidifying portion of the aggregate. The solidifying portion, whether seeded or slabbed or whatever, is actually at a temperature below the range where only the right phase is solid. So by mixing it with chocolate above that temperature, the net temperature of the whole mass goes up, into the critical range. It’s also, therefore, equally possible to temper by bringing the whole mass slightly below temperature and then slightly raising it. Whatever the case may be, this mixing or reheating is Step 3.

quote:


You also need to constantly mix.


This is crucial throughout the process for 2 reasons: first, to keep the whole mass at an uniform temperature, for otherwise some parts will be cooler than others, and second, to distribute the forming crystals throughout the mixture so that at every location there will be crystals in the right phase to act as nuclei. This is a major reason why simply letting a mass cool undisturbed almost never works: because you can’t guarantee evenness of temperature or crystal distribution.

Milk chocolate is particularly finicky because the milk fat (butter, in essence), has its own crystallisation point, slightly lower than cocoa butter, and you must temper in the range where the milk fat solidifies with the cocoa butter in the right phase, even more narrowly distributed than the difference between the right and first-wrong cocoa butter phase. It’s a very sensitive emulsion that easily separates. Furthermore, overheating definitely breaks the emulsion once and for all, so you can’t heat as high either. I’m honestly surprised that you’ve gotten away with what you’ve done in the past – you’ve been very lucky. I would say definitely, profile your chocolates, i.e. find the melting point/crystallisation point/reheat point, then try again.

Alex Rast
Alex_Rast_Alternate@hushmail.com

Alex Rast Alex_Rast_Alternate@hushmail.com
June 28, 2008
10:15 pm
Alex Rast
Manchester, United Kingdom
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October 13, 2009
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quote:


Originally posted by Ilana

I agree that the flavour and texture is certainly affected in a negative way. I was referring to shelf life in terms of health!


Yes, I wanted to emphasize that fact because there is a dangerous misconception that untempered chocolate is unaffected. You see it printed even on chocolate wrappers by companies who should know better. They may well be thinking in food safety terms, but this is not the public perception – who assume that quality is likewise unaffected – and the unfortunate side effect is that many shops store chocolate poorly and don’t understand that bloom is a real defect, to the extent that even when you explain it to them they don’t believe it. IME, therefore, unless the wording is specifically in the format of “the safety of bloomed chocolate is unaffected but the flavour and texture will be” or something else that makes clear the effect, stating that bloomed chocolate is unaffected perpetuates the misconception and should be avoided.

quote:


By the way, if the chocolate is tempered incorrectly, there may be more of a tendency for the filling to be less well encased and thus more exposed to air. This can affect shelf life interms of health, if there is a filling. What do you think Alex?


It certainly makes it more brittle, therefore more prone to cracking and other obvious problems. With respect to filled chocolate it’s also gummier in working, therefore never coats as uniformly, increasing the risk. If it actually turned out that the filling were unexposed, there wouldn’t be a problem, so it’s not a given that poorly tempered chocolate diminishes food-safety-related lifetime, but it magnifies the risks.

Alex Rast
Alex_Rast_Alternate@hushmail.com

Alex Rast Alex_Rast_Alternate@hushmail.com
June 29, 2008
8:26 am
Ilana
Israel
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Again, thanks!

Ilana Bar-Hai www.ganache.co.il
June 29, 2008
4:45 pm
Gracie
Chippenham, United Kingdom
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June 23, 2007
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10

Hi,
As the above posts have said, you’re missing the movement part of the equation to achieve a good temper. There’s no need for me to elaborate further on the science.
It strikes me that your method is probably the most risky (in that you have water present) and difficult to control.
I started out using the microwave to melt the chocolate to about 40 – 50 c depending on the type, then using the seeding method by adding unmelted drops of the same chocolate…you need about one third to a half of the weight of the melted chocolate, but you must stir constantly.If you have the odd little lump you can gently warm with a hair drier without overheating.
By far easier and quicker, once you have the hang of it, is to cool almost all of the chocolate by working it back and forth on a marble slab to about 27c then scrape it back into the pot with the last remaining hot mass to bring it to working temperature.

I am lucky enough to have a granite worktop maker round the corner, and he polished up a nice piece of dense black granite for me which I use for this. The granite is about 70cm square, and for worktop makers that size usually goes in the skip so I only had to pay for the polishing! It may be worth searching your yellow pages and using a bit of charm.
I’ve found that chocolate tempered by this method remains much more fluid and easy to work at cool temperatures than the same chocolate tempered by the seeding method.

If you want to borrow a book on the basics of tempering etc, drop me a mail. Where in the Uk are you?