Ask the Alchemist #89


I am having a terrible time tempering my chocolate (no surprise!). I can’t mold it all up before it starts to thicken and most of the bars have these funny swirls on top. What am I doing wrong? I am bowl tempering and using your hobby grade molds. First off, you are doing nothing at all wrong really. It’s just about your technique and equipment.

Those swirls are not bloom (based on the photo you sent). If you notice, they really are not discolored as bloomed chocolate would be. Instead they just catch the light and you can see something ‘odd’. That is caused by the mold you are using. Namely the semi-flexible ‘hobby’ grade mold. This is why they are considered hobby grade. They don’t give a professional look. As tempered chocolate hardens, it contracts slightly, pulling away from the mold. In a mold that can flex, it pulls away in parts and the result is the unevenness you see. That is why professional molds are usually many times thicker. They resist that motion and flexing and you get a smooth, more even appearance. And it is why so called commercial molds are very heavy, rather expensive and totally rigid.

What can you do about it? Nothing really. No amount of support will change the fact that the mold flexs. It is worse the larger the mold is, so about the only thing I can really suggest is staying with small molds or molds that don’t have a lot of flat surfaces that show this distortion effect.

distortion.jpg

(click to embiggen) As for the issues you are having with your bowl tempering, it sounds like you don’t have it insulated and you are trying to beat the clock as it were. When I bowl temper, which is most of the time, I simulate a tempering machine as well as I can. I put my bowl of chocolate that is ready to go into molds into a larger, but shallower bowl filled with warm water at 90 F. The specifics here that are important is that because the outer bowl that holds the water is more shallow, there is no way for the water to over flow into your inner bowl containing your chocolate. And water is a fantastic insulator. Having that mass of water surrounding your bowl of chocolate keeps it at 88-90 F with very little effort. And if I am doing a lot of chocolate I usually keep a bowl of 95-100 F water around. If near the end of tempering it starts to thicken, I just move my chocolate bowl to the warmer bowl. And finally, I stir my chocolate after each and every ladle full of chocolate I removed that goes into a mold. It helps keep the chocolate temperature nice and even, and helps inhibit the chocolate from thickening faster than it should. And I find I slow down and relax if I have the rote procedure. Ladle, pour, rap the mold, stir, ladle, pour, rap the mold, stir…..soothing.

Basically set yourself up NOT to rush. The above works for me.

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