Chocolate sticking to molds
Posted in: Tech Help, Tips, Tricks, Techniques
You need to pre heat the molds to your usage temp of your chocolate to avoid shock then you should get contraction and release if you are in temper.
Thanks all for the response. It definitely seems to be a temperature issue we are battling with. Unfortunately, we work in a shared kitchen so there are a lot of variables out of our control.
What we are finding out though, is if we put a wax paper liner down on the metal sheetpans just before placing the mold on it that it seems to give enough of a buffer that the mold fully releases. Don't ask me why that's working so well but it has thus far!
From my limited experience...
Flexibility of the mould can also lead to uneven release and cooling marks. I noticed this especially with large moulds with flat areas without much detail. As the chocolate shrinks back from the mould it releases on the edges and corners ok: there it cools first and the mould is more rigid due to it's shape. The middle of the chocolate is the warmest and solidifies the last, but as the mould flexes with the shrinking chocolate it doesn't release well or stick. When this happens to me, the chocolate will still release hard and shiny (sometimes I have to give the mould a quick tap to release), but you see visible cooling marks where the chocolate released in stages.
I can imagine better cooling will help too. But as I can't control my cooling very well, I don't know to what extent.
Do you know how your moulds are made: injection moulded or vacuumform and what is the material thickness? How complicated/intricate is your design?
I prewarm my moulds just above room temperature, that seems to give better results. I cool at 8-10degC with the moulds slightly raised, so air can circulate all around. On the 'to-do' list is to put a fan inside the cooling fridge, to see if forced air circulation gives better results. Now it can take some time (hours) before the whole piece has cooled sufficiently and the middle finally releases from the mould.
According to Callebaut, moulds should be as close to room temp (20 C) as possible, but they also recommend slight preheating. So, around 25 C?
They go on to say that cooling is best done at 10-12 C, followed by time in the fridge. Circulation during the cooling phase is important, although this winter when it was between 10-15 C in my workshop (there is no heating in this country lol) I rarely had blemishes even though I had no special ventilation so I'm thinking at that temp as long your 10 C space is not too small, you'll be fine.
Source: http://goo.gl/BIjVFC (first result, PDF format)
Temperature can definitely be a factor, but so can humidity. Hot, humid days make molding chocolate difficult. It could be that the molds aren't cold enough, though. If necessary, after you have poured the chocolate, put them briefly in a temperature-controlled refrigerator to harden completely, and don't try to remove them before they are fully set. The larger bars mean you need more cooling time. Don't freeze them, though! You should be able to keep the trays at room temperature while filling them (as long as the room isn't too hot!) Then cool them, so that the chocolate can pull away from the edges.You don't want the trays cold from the start, because the chocolate will harden too quickly at the bottom, and warm chocolate will spill over and solidify around the edges making the bars stick. You want the bars to cool evenly.
I've been having an intermittent issue where my chocolate sticks to molds. It will always release around the edges but the middle (sometimes a large area, sometimes a small area) sticks to the mold. When I let the chocolate sit overnight, usually the surface is dull, but it snaps and appears to be tempered properly.
I think I've discovered that the temperature of the metal trays I'm placing the molds on influences whether this occurs or not. Has anyone else experienced this? What is the ideal temperature to keep my trays at when placing my molds onto them. I'm using custom food grade pvc molds and my bars are rather large at about 7.5 inches x 3.5 inches. Thanks in advance!
i am curious if anyone has any info regarding rising cacao prices and if a there is a shortage? I read an article, but it seemed to focus on the African beans and large multi national companies.
I've also heard from another maker who is using a VCM for pre-grinding in production. At some point, I'd love to upgrade to one for the larger bowl size.
Googling confirms that the original Cuisinarts were manufactured by Robot Coupe. Not so much that they stopped working together so Cuisinart could build in some plannedobsolescence.
Several of the reviews for the model I bought claimed that they had owned and abused it for many years. We'll see how it holds up to chocolate making...
Hi Dave. I'll post the results when I do a larger batch.
" the first Cuisinart food processors were private label Robot Coupes "
hunh! I did not know that.
Vertical Cutter; good to know.
Corona mill; cheap materials- somehow i knew that might come out in the wash. I havent seen much quality in mid americanmanufacturing, IMHO.
thanks Clay
The point is that there are many options at many price levels for every budget and situation. I've seen vertical cutter mixers in production - so I know they work. You get very large batch capacity (compared with most food processors). Used, they can be had for $3500.
Perhaps ironically, I was told that the first Cuisinart food processors were private label Robot Coupes. Problem was, they never broke or wore out. So they were redesigned with smaller motors and in plastic.
Of the options, the Corona grain mill is the one I can't recommend even if motorized. These days they are made with cheap materials and, in particular, it's hard to put pressure on the grinding plates and get a consistent texture. That's from personas experience using them in Belize.
Im not surprised to hear the Cusinart does good. Ive used robo coupes for 20 years and I gotta be honest Ive never been impressed with their power (or is it power delivery). That being said they do take a good amount of abuse (Ive seen one vibrate off the counter and still run. Not bad for a #15 machine.) I do remember using a 20 year old Cusinart this past summer and I was impressed with it.
One of my beefs with the robo is the small bowl, yes there are different sizes. but the your well into the >$2500 range.
I know Clay suggested using a vertical mill chopper, Ive only used them a few times. Without trying it out, I would be hesitant to put my $$$ into one. For one thing youd have to keep stirring it with the built in stirrer. I do like the idea of the corn mill. Load a hopper, and watch it. Possibly less involved than the vertical mill.
just my 0.02$
Thanks Ben that's good to know!! I'll be curious to hear how long it eventually takes you with a much larger batch of nibs and whether it scales linearly. For instance, would 15 kilos take you 50 minutes? And then of course, it would be good to hear your impressions of the heat given off by the food processor after a much heavier load.
Dave
I've recently purchased a 20-cup Cuisinart food processor. The motor specs are roughly comparable to the Robot Coupe I was looking at, but it has a larger capacity and is less expensive. It also has overheating protection to avoid burning out the motor.
I used it for the first time over the weekend on a small (approx. 1.5 kilo) test batch. It easily pre-ground the nibs to a gritty, but runny, liquor in about 5 minutes.
Afterwards, the motor housing was cool to the touch. It has an internal fan for the motor and the air blowing out of the vents never noticeably warmed.
I will be doing some more tests to figure out a few things. I imagine that theres a point of diminishing returns, where it no longer makes sense to keep running the liquor in the food processor.
-Ben
Cheebs, is the Nixtamal grinder that you are referring to have metal disc or is it using stone wheels for grinding?
Robert
The machine shown in the video Olive and Sinclair video is fairly large and couldn't be considered a replacement for a Champion juicer. What you're probably looking for is a tabletop appliance like the Nixtamatic. Here's a video of one in action. Still hands-on, but not so much as the Champion.
Yep, Mexican corn mill = Nixtamal
This is probably outside of your budget, and I haven't seen anyone else do this, but Scott Witherow at Olive & Sinclair uses (or at least used to use) a Mexican corn mill. Check out the attached video at about the 1:25 mark. Looks like it works fairly well too.
Dave,
Nope, I haven't gotten one yet.
Ben
Here in Guatemala a lot of people use Nixtamal grinders to grind cacao. There are many models for sale in the US. There's a video in my profile about artisanal cocoa butter where you can see one in operation. Check around the 1:30 mark.
Ben,
Have you managed to try out the Robot Coupe VCM on your nibs yet? If so, how did it go?
Dave
Alan -
I think the point is that at the scale you're working at now, anything larger or more expensive than the WonderMill Wonder Junior just doesn't make sense. It's about $250 with the drill attachment, though I would try to motorize it using the optional pulley) and you're not going to get better price/performance in a pre-grinder.
This doesn't make a "proper" liquor. However, anything you can do to reduce the particle size before you put it in your melangeur is going to speed the process up considerably. As Ben notes, warming the stones gently is also a good idea (use a small resistance heater that doesn't get hotter than about 100F, put it in the bowl a couple of hours before you want to use the melangeur - or overnight - and cover with something that will help keep the heat in.
From a tech perspective I think colloid mills are a better bet for oily products like cacao than hammer mills. I would be careful, however, about buying machines from China. There's a thread on the new melangeur from Kudvic where Victor talks about some of the issues he had with Chinese-made machines that led to his developing his. His experience echoes mine pretty closely.
I never replaced the grinding plates, but have spoken with another chocolate maker who used a new PN2 version. Their results were similar to mine.
For most of the time I've been making chocolate, I've just put the nibs straight into the melanger. The belts that come in the melangers are basically terrible. They almost always break and need to be replaced. I replaced mine with power-twist fiberglass link belts, as recommended in several posts here on TCL and on the Chocolate Alchemy forums, and have not had a problem with them since. Also, warming the bowl, roller stones and nibs helps a lot.
http://www.ebay.ca/itm/Automatic-continuous-Hammer-Mill-Herb-Grinder-pulverizer-machine-25KG-per-hour-/150975226935?pt=LH_DefaultDomain_0&hash=item2326d32437
and / or
http://www.ebay.ca/itm/NEW-Vertical-Sesame-soybean-Peanut-Butter-colloid-mill-grinder-JML-65-/160992669808?pt=LH_DefaultDomain_0&hash=item257be93070
as I try to wrap my mind around what we are doing, I realize that what we are doing needs to be measured. The final product needs to be <30microns, but not everything is measured the same way. Not everything can produce a set of standards that will tell you how a machine will perform. Not everything has the same standard, like the p-b machine. It may only apply "x" amount of force, and produce "x" size particles. But then there is the variables. A cocoa nib has "x" density and requires "x" force and heat to create "x" product....
Aint life funny
hmmmm...
did you have/try new, grinding burrs? being used, it could have been worn. Just trying to figure out where/how the differences in results came from. Model? Used burrs?
Im leary about a Champion juicer because from the little reading Ive done on CA, it sounds like the juicer (parts) will/do wear out within a relatively short time. 100#? 1000#?
anyways a small machine like that is out of my league for home use! maybe a small p-b maker. Having burnt out a belt on my melangeur trying to do make the liquor IN the melangeur, I think its time I do it properly.
I was using the PN1 version, which was the older version of the PN2 you linked to. I got it used, but it went for over $2k new.
I tried, but wasn't able to effectively feed the paste through the grinder again.
I'm not sure what brand of food processor it was. Sorry.
I kind of expected to hear that results may vary. The machine I called Pleasant Hills about is a huge commercial machine, $2500....so its probably got a bit more robust grinding system than a small tabletop unit. Its made to make smooooth butters.
Did you ever try putting the "paste" through the home table top butter maker again? Wondering if a second time round would yield better results.
What kind of food processor did/do you use? Im a CuisinArt fan, but I remember Chocolate Alchemy saying some just dont cut it.
My concern isn't that it will grab the nibs--I think the gap between the first two rollers should handle that fine--so much as how fine it will actually grind.
Ben,
It seems we think alike. I ran across the monter brewing website a few weeks ago, too. Its more than I want to spend for a small hobby, but maybe?????
I must admit though, Im curious to know how well the monster mill grinds....ugh, I hate being curious. Any idea how the steel roller, grab the dry nibs? It seems like they might just spin ans spin and spin.....That being said, it works for the barley/wheat which are possibly larger and harder, and drier(?)?
Cake batter consistency would be great, but it's not what I got when using one. I've spoken with another maker who was using one for a while, too, and their results were more like what I was getting than cake batter.
Well......
I called Pleasent Hill Grain Nut Butter Machines ( http://www.pleasanthillgrain.com/nut_butter_machine.aspx ), at one point they did do a test with cocoa nibs (they couldnt remeber the size of the peices, but I think to us its its irrelavent), and she said, it comes out like a chocolate cake batter. Then hardens after 30 minutes or so.
Do what you will with the info....
Cheers
Alan
Sorry, just noticed that you referenced the youtube video in your original post. Not sure how I missed that...
I've used the Olde Tyme Peanut Butter Grinder in the past. The results were about the same as shown in the Wondermill video, although much faster.
The only thing that I've tried that actually made liquor--as opposed to a thick paste--was a food processor. It worked really well until I burnt up the motor. In another thread here, Clay mentions Vertical Cutter Mixers (VCMs) for pregrinding. They're basically just big, heavy-duty food processors.
I've also thought about using a grain mill like are used for beer brewing. One I've looked at is one of the Monster Mills, which are adjustable from 0 to .065" according to their site:
Ben, Thanks for posting up, I appreciate it.
I know you can, but how well does it work? It seems to me, the paste that comes out of the wondermill, is about the same consistency as when the nibs start to "gunk up" and stick when grinding them in he melangeur.
Has anyone tried a peanut butter grinder?
Cheers
Alan
There's a video of the Wondermill JR grinding cacao here:
Hey Chocophiles,
Ive been doing more and more, playing at home with small batches of beans. <3#. I still dont have a way to make a proper liquor. Doing it in the melanguer, is....far from good and requires babysitting for ~45 minutes....
I was wondering at how well a Wondermill JR or a peanut butter machine would work? The Wondermill JR has a small youtube clip saying it does mash it up, but I was wondering how well that paste processes in a melangeur.
Cheers all!
In all my internet explorations I had not come across your very useful site; I am glad you pointed it out. And I appreciate your comments on the Felchlin Cru Sauvage in particular. I was, however, surprised at your review of Valrhona's Caraibe (my current dark chocolate), namely, that it was too sweet. I am thinking that if you found that product too sweet (I found it too bitter, except perhaps with the sweetest of ganaches), we have very different palates, and I had better prepare myself for tasting Cru Sauvage. Thanks for your help.
I also really enjoyed the Cru Sauvage, even though I only had it in couverture. (I forget the term for those little round discs.) See my review notes attached. I think it would be an excellent choice if it fits your budget.
I have also reviewed 4 other Felchlin chocolates. You can find my reviews at ChocoFiles .
Vera,
Thanks for those very helpful links.
Hi Jim, Excellent choice! I love Felchlin, especially the Cru Sauvage. You can find more information of both Grand Cru's on their website:
http://www.felchlin.com/en/product/cacao-maracaibo
http://www.felchlin.com/en/product/cacao-bolivia
Call the distributor for samples and taste them. I'm curious to your opinion!
http://www.felchlin.com/en/continent/usa-central-south-america
Chocolove, Vera
I am interested in finding a different dark chocolate and am thinking of Felchlin products. Unfortunately I have not seen a source for small amounts of the chocolates, and so am seeking comments from those who have tried the two in which I am most interested.
The two chocolates are Cru Sauvage and Maracaibo. As a point of reference, I started my chocolate experience using several different Callebaut products (including their 70% dark), then moved to Valrhona Caraibe, which I am finding a little bitter for my taste (I have tasted most of Valrhona's dark chocolates and Caraibe was my favorite).
I have read good things about the two Felchlin products. Any comments will be appreciated.