artisanal thinking

We knew it couldn’t always be biscuits and gravy… In my latest batches, the fifth and sixth overall, consisting of Peruvian and Panamanian Cacao respectively, I’ve run into my first considerable troubles with the process. However, as nothing is bad—just instructive, I’ve identified several key areas for process improvement.

Currently the cardinal question is how to store tempered chocolate during molding. When chocolate comes off the grind, it is at 130F and at this temperature, no crystals are present, they’ve all melted, the chocolate is raw and without its temper. The granite bottomed bowl of the Santha grinder is also at 130F, and with this amount of thermal mass, the chocolate in this container cools fairly slowly. I can take lots of time scraping all the chocolate out of the melangeur and into a holding bowl with no worries.

The story is different, however, once I temper the chocolate and by doing so, reduce its temperature to 90F. If I ever heat this tempered chocolate to above 92F, its stable β crystals will start to melt, taking the heated chocolate back to the high-entropy, dog-eat-dog world of a type I-VI crystal forming free-for-all. On the other hand, if the chocolate cools too much, below say, 82F, it will start to thicken noticeably, other crystals start to form, and it will become impossible for me to suck up this chocolate fudge into my syringe, squeeze it into a mold, and smooth it out in its tray. The chocolate may be tempered, but the bars I would mold can only be called, ‘ugly.’

Iteration #1—fail, #2-4—success! #5—return of the trouble

With this background, we can discuss numero uno problema: what kind of bowl or holding system should I use to store tempered chocolate so that it doesn’t cool too quickly for me to mold, and I don’t have to heat it back up, risking destroying the temper. For batches 1-3, when I was making 3lbs a batch, I filled to the brim the largest ceramic bowl I owned. Ceramic retains and does not conduct too much heat, and since the batch size was small, it did not take long to mold, keen. In batch #4, the first of the 7lb batches, I used a melamine bowl. Later, I was a little nervous—melamine is some kind of metabolized pesticide and was recently in the news because it has been appearing in food products from China, but apparently it is kosher to make dinnerware out of a mixture of melamine and formaldehyde (with this plate, you can kill and preserve your insects!)… This thick plastic bowl also retained heat quite well, at the end of the mold, my chocolate may have been thickening a bit, but the bars from this batch all looked good and I didn’t have to resort to hair dryer re-heating.

Batch #5 brought the trouble. I no longer had access to the melamine bowl, so I attempted to use one of the only concave objects of sufficient size that I own, a steel stockpot (with aluminum base for efficient heat distribution). What I forgot was that heat distribution was precisely what I don’t want! After molding only a couple trays of bars, the chocolate in this pot was already thickening up. A second manifestation of this same issue arose with some chocolate I had separated from the rest and mixed with nibs to make some experimental nib bars, one of which you can see on the right. Because this was only a small amount of chocolate, I could put it in a thick ceramic bowl, but again I neglected to consider that both the bowl and the nibs I was mixing into my tempered chocolate were not 90F, but room temperature. This caused nib chocolate to also cool down very quickly—after one tray, the chocolate was already non-malleable. At this point I began looking for my hair dryer, but I couldn’t find it right away, and in desperation attempted to smooth as best I could the thick chocolate in my molds. After trying this with some more of the plain dark chocolate, we were unable to draw it up in the syringe and I searched again for my hair dryer.

Finding it this time, we started giving short blasts of hot air to chocolate in the molds and to our metal pot of chocolate. I don’t recall using my thermometer to monitor the temperature of the chocolate being blasted, instead we just stirred and heated until the chocolate again began to flow. We finished by molding some, heating some, until all the chocolate was molded and cooling in the fridge. As you can see from the picture above, some of the chocolate was pushed too far and lost its temper. When using the hair dryer to heat chocolate already in a mold, it is likely that you will heat the chocolate at the surface to above 92F, untempering it, but the chocolate in the center of the bar will likely stay cool and tempered. You end up with a bar that is not as bad as molding pure untempered chocolate, but the surface still has a poor look and feel. For this batch, the final thing to note is that I made another experimental bar, this was plain dark chocolate not mixed with anything, but I drizzled some almonds, raisins and sea salt on the ‘back’ of the bar, the side facing ‘up’ from the mold. I pressed the fruit and nuts in slightly to the bar so that they would be gripped by the hardened chocolate, but still stick out of the bar for aesthetics.

Iteration #6—different solution, same problem.

I was a little disappointed with my technique in Batch #5 and I didn’t want to dignify these bars with a wrapping party. I was still rolling on towards Batch #6, however, and so I thought again about what object I could use to store my hot chocolate. I thought maybe choosing a metal pot with greater thermal mass might do the trick and I was in luck, because I have a Le Creuset dutch oven. I figured that cast iron would retain enough heat to allow me to mold. I was wrong! I experienced the same two expressions of the same single problem. I again tempered my chocolate, poured it into the dutch oven and culled some to make more nib bars. I again did not pre-heat my ceramic nib-bar-bowl, nor did I preheat the nibs, and I again ran into the same trouble molding these bars. While I was doing this I covered the pot of pure dark chocolate, and I successfully molded a tray or two of bars, but again the metal was dissipating heat too quickly and I really had to resort to the hair dryer this time.

It took me maybe two hours to mold my bars (I was up until 2am!) as I kept repeating a cycle of stirring and heating the chocolate, monitoring it with a thermometer until it got too about 91F, then I would mold a tray of bars as fast as possible and have to come back to heating the chocolate again. After iterating this several times, I began to grow skeptical that what I had in the pot was even still tempered chocolate, it seemed unlikely. If it was untempered, my labors were in vain, and I might as well heat it all up to say, 100F, be done with the molding and try again to temper and mold the next day. This is eventually what I did, but I was surprised to discover that before that point the chocolate I was working with seemed pretty good. Most of my bars, though labor intensive to mold, looked decent because of it, only after I had grown frustrated and resolved to end the process did I really get untempered bars. To the left is an example of a bar halfway through the process, it is ‘bumpy’ because I squeezed it out of the syringe in a ‘back and forth’ pattern, and since the chocolate was not so viscous, shaking the molds only smoothed the ridges so much.

On the experimental side of Batch #6, I was planning on making a cinnamon + cayenne pepper bar, but given my trouble with incorporating the nibs, I held off on this and just made more tests of the nib bar and the almond/raisin bar. It is definitely easier to use the style of pressing things into the back of the bar rather than incorporating them into the chocolate and then molding. Therefore, I may try some more experiments with dried fruit, nuts, or other pressable things, rather than powders, which must be mixed.

After these two batches I decided to take some time off, and have been considering my options. Today I biked over to the Habitat ReStore and picked up a large ceramic pot which I think should solve some of the cooling troubles. The professional solution is to buy a chocolate holding tank, like this ’small’ tank or this industrial tank. In the image you can see confusingly named fellow chocolate maker, Rogue Chocolatier with his arm on his tank. If this ceramic bowl doesn’t work, I’ll buy another melamine bowl, and if that doesn’t work, then…

I’ve also made a big plunge and put in an order for 110lbs (ie: one ‘bag’) of Panamanian beans, I would have preferred 110lbs of Peruvian, but they are not for wholesale. I’m dwindling on the stock of 35 lbs of beans I received two weeks ago, so this should last for at least… a month. I’ve also tried to become a little more business like and resist the urge to give everyone I meet free chocolate. That is not sustainable, and I still have not broken even on any batch of chocolate, but I visited the bank today to make a deposit of my sales over the last several weeks, and I think I may be in the black in a couple more weeks. Finally, blog-wise, it seems impossible to post more than once a week, but I still have more to say! I’ll post next time on process improvements and ideas in the wrapping and packaging of our bars.

This entry was posted on Saturday, September 5th, 2009 at 3:58 pm and is filed under Chocolate Making. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.