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Need easy-to-find alternatives to food-grade silicone, to make molds. Would aquarium silicone do?? Answered

Hi. I would really like to make some food-grade molds (candy molds). I know that food-grade silicone is the way to go, but here in Norway, it is not that easy to come by, and when you do, it's very expensive. My question is whether there are viable alternatives, that lasts. (not a make one, and break it thingy..) I know that aquarium silicone is supposed to be non-poisonous, but will it do as a mold material? Or are there other alternatives I can make myself? or buy at a hardware store.. I know there are a lot of silicone products out there.. Surely some of them would be safe to use in food prep? Thanks for all answers. Best regards, Klaus, Norway.


. Aquarium RTV is just like other RTVs except it doesn't have any additives. Eg, anti-mold agents in bathroom caulk. When properly cured, it should be very safe at room temperature or below - it doesn't harm even very sensitive marine invertebrates. Heating may be a problem.

Well.. It would be heated in a way.. when adding hot gelatinous candy-goodness into the mold. Hmm.. Anyone know what exactly food-grade silicone putty is made of? I mean chemically speaking, is it really that different from the other silicons (apart from the ones with anti-mold substances and such..) Hmm... anti-mold.. now that's ironic... seeing that I'm looking for a way to make "molds" :-)

. I would think that anything below 100oC would be OK, but can't say for sure. Didn't find any temp limits with a Q&D web search.
. Silicone covers a lot of ground. If I understood what's I've read in the past, aquarium sealant is the same as bathtub sealant, except it doesn't have any additives (colorant, anti-fungals, &c). This would lead me to believe that it is safe for cooking (if it's safe for an anemone, it must be safe for me), but I'm no expert.

They do say to keep your friends close and your anemones closer ;P but seriously, there are also Vacuuform and blowmolded candy molds, and even cornstarch!
 if you do intend to use an RTV (room-temperature vulcanization)silicone, keep in mind that using another support material(a mold jacket, etc.) can help you to get better detail and less "travel" (distortion)
though your best bet would be a moldmaking silicone, because of shore hardness and durability factors,
an appropriate aquarium cement could be done in layers with either power netting (cheesecloth may not stretch and may do more mold damage), polyfiber, or inside a keyed "hard piece" maybe a drilled piece of polypropylene bottle or pipe.
you also may want to look at the older methods of sandcasting, which I'm theorizing here, could be used in conjunction with the cornstarch method? somewhere between oobleck and green sand?
i might have to try this myself before advocating this part.....;)

i was wondering about this also, since no local stores sold food grade silicone, and i am to impatiant to wait for it to be delivered. so i looked at home depot, and the aquarium safe silicone says on the back, "safe for food contact when cured and washed" so that pretty much answers the question, however, i found that the price for aquarium safe silicone is pretty close to food safe silicone. so it might not be very helpful...

This may seem a little off topic, but it works that way with polyurethane (wood finish) The make a special polyurethane that is food-safe, and it costs a fair amount more that the standard types. The additional cost is partly due to the fact it gets certified safe by the FDA here in the US. They pay for the certification, but the formula is really no different than standard polyurethanes. A cure time of 30 days is suggested with polyurethane to be food-safe however.

Mmm, people might be adding a premium to products simply because they're certified as "food-grade" but they may simply be more expensive because of it. Don't really know, but when the polymer is finally set and cured it should be fairly inert if not treated harshly. Try it I suppose? L