Chocolate forms/moulds: is silicon an option?

[Odysseus]

Hi all,

I was checking for chocolate forms/moulds and was wondering whether silicon ones or ok to go with.
I haven't found anything against on the web nor here on the cass forum.

So, is it ok to go with silicon forms? If not, what are you using?

 

[RyanX]

I was actually wondering the same thing. The chocolate bar moulds I've seen have either been silicon or polypropylene plastic, and I'm not exactly sure which is the safer material as far as food chemistry goes. I haven't seen moulds made out of any other type of material, but it could be that I haven't looked hard enough.

As far as rubberized silicone goes, it doesn't sound like there is much data yet to know for sure what health effects it may have. Teflon was deemed "safe" and "inert" in the beginning too and look how that turned out. From Scientific America:

_http://www.scientificamerican.com/article.cfm?id=earth-talk-silicone-tally

Silicone Tally: How Hazardous Is the New Post-Teflon Rubberized Cookware

Although most people will probably not have a problem with silicone cookware, those with chemical sensitivities might want to stay away until more definitive research has been conducted

Dear EarthTalk: Are there any health hazards associated with the use of the new silicone bake ware and cooking utensils? I have found information associated with the hazards/benefits of Teflon and other cookware but nothing on the use of silicone.
—Jean McCarthy​, Sebastian, Fla.

With all the negative press about Teflon and about metals leaching out of pots and pans, consumers are on the lookout for cookware that’s easy-to-clean and doesn’t pose health concerns. Silicone, a synthetic rubber made of bonded silicon (a natural element abundant in sand and rock) and oxygen, is increasingly filling this niche. The flexible yet strong material, which has proven popular in muffin pans, cupcake liners, spatulas and other utensils, can go from freezer to oven (up to 428 degrees Fahrenheit), is non-stick and stain-resistant, and unlike conventional cookware, comes in a range of bright and cheery colors.

But some wonder if there is dark side to silicone cookware. Anecdotal reports of dyes or silicone oil oozing out of overheated silicone cookware pop up on Internet posts, as do reports of odors lingering after repeated washings. Also, silicone’s image may be forever tainted by problems associated with silicone gel breast implants—some women with earlier generations of these implants experienced capsular contracture, an abnormal immune system response to foreign materials. And while theories about silicone implants’ link to breast cancer have since been debunked, the damage to silicone’s reputation lives on.

It’s sad to say, but since the use of silicone in cookware is fairly new, there has not been much research into its safety for use with food. Back in 1979 the U.S. Food and Drug Administration (FDA) determined that silicon dioxides—the basic elements in silicone cookware—were generally recognized as safe to use even in food-grade contexts. But the first silicone cookware (silicone spatulas) didn’t start to show up on store shelves until a decade later, and the FDA hasn’t conducted any follow-up studies to determine whether silicone can leach out of cookware and potentially contaminate food. For its part, Canada’s health agency, Health Canada, maintains that food-grade silicone does not react with food or beverages or produce any hazardous fumes, and as such is safe to use up to recommended temperatures.

Consumer advocate Debra Lynn Dadd, who steers clear of Teflon due to health concerns, is bullish on silicone cookware after investigating potential toxicity. “I tried to find some information on the health effects of silicone rubber, but it was not listed in any of the toxic chemical databases I use,” she reports, adding that she also sampled material safety data on several silicone rubbers manufactured by Dow Corning​ (which makes some 700 variations). “All descriptions I read of silicone rubber describe it as chemically inert and stable, so it is unlikely to react with or leach into food, nor outgas vapors.” She adds that silicone “is not toxic to aquatic or soil organisms, it is not hazardous waste, and while it is not biodegradable, it can be recycled after a lifetime of use.”

So while most of us will probably not have a problem with silicone cookware, those with chemical sensitivities might want to stay away until more definitive research has been conducted. In the meantime, cast iron and anodized aluminum cookware remain top choices for those concerned about harmful elements leaching into their cooked foods.

From another article:

_http://www.environmentalhealth.ca/greatchefs.htm

Silicone cookware is the new kid on the block. Its flexible and its cheerful colours make it popular. But is it safe? Health Canada says yes. They say that tests show silicone to be stable and inert, and that there are no known health hazards. But Health Canada also told us that Teflon was safe. A more reliable opinion comes from Debra Lynn Dadd. Author of Nontoxic, Nature and Earthwise and Home Safe Home, Dadd is a strong advocate for less toxic living. Dadd’s opinion is that “silicone bakeware and other kitchen utensils are safe to use.

“Silicones are made chemically by creating a "backbone" of silicon (from common sand) and oxygen molecules, a combination that does not occur in nature. Then various other synthetic molecules are added branching off of the main silicon-oxygen line to create hundreds of different silicones that range from liquids to rubbery solids,” Dadd writes. (Dadd's info packed website can be found at www. dld123.com). But some consumers report that silicone does offgas, and raise concerns that additives may include petroleum or other harmful ingredients. While silicone cookware may be funky and fun, there is not a lot of evidence yet about safety or harm. In the past, the health hazards of some new products, like Teflon, were not revealed for several decades. In the case of silicone, it might be more sensible to be cautious.

Generations of cooks produced first class meals and baked goods in the days before nonstick coatings. It may take a bit of adjustment to find just the right heat, baking time, or amount of oil to add to a pan, but with a little work, great meals can be yours without the health risks of nonstick cookware.

Then from here:

_http://www.drweil.com/drw/u/id/QAA400274

Silicone is a synthetic rubber which contains bonded silicon - a natural element, abundant in sand and rock - and oxygen. Although I still prefer stainless cookware, silicone kitchen products seem to be everywhere these days. You can now get cheery, brightly colored cake pans, muffin tins, colanders, potholders, baking mats, ice cube trays, pastry brushes, spoons, cake pans, and even roasting pans made out of silicone. Sales of these products have mushroomed into the millions. The advantages of silicone include heat resistance, flexibility, the fact that it can go directly from the oven or microwave into the refrigerator or freezer and that it is generally easy to clean. Silicone containers are also environmentally friendly; the snap-on lids can eliminate the need for plastic wrap or aluminum foil.

Silicone appears to be safe. It is an inert material - nothing used in its manufacture will leach into foods. So far, no safety problems have been reported, but if you're concerned, stick to silicone kitchen tools (such as spatulas) and avoid bakeware.

You might be interested in an assessment by New York Times food writer Marian Burros about the usefulness of silicone cookware. After testing a variety of products, Ms. Burros reported that the baking pans are not as nonstick as you might think: she found that you do have to grease them if you want your cakes and muffins to slide out unscathed. She had the most trouble with loaf pans, cake tins, brownie pans and Bundt pans. But she gave a rave review to potholders that double as trivets, mitt-type potholders, and a spatter screen that she found actually did prevent grease from speckling the stove top. Some of the products tested by the Times proved impractical, among them silicone garlic peelers, lemon squeezers, and measuring cups.

When you buy silicone products, make sure that you get good quality ones that don't contain any filler. Ms. Burros recommended pinching and twisting a flat surface to see if white shows through - if so, filler has been used and the product may not be uniformly heat resistant and may impart an odor to food.

Since silicone cookware is relatively new, we don't know much about how long it will last. But since it is comparable to other types of cookware, replacement should not be too much of a hardship.

Andrew Weil, M.D.

As far as polypropylene plastic goes as a mould material, there's a lot more known about chemical toxicity. It seems that the stuff is most toxic when heated, which may not be an issue if the chocolate you're pouring into it is not too hot.

_http://www.environmentalhealthnews.org/ehs/newscience/polypropylene-plastic-additives-break-down-with-heat/

Chemicals with unknown toxicity form when polypropylene plastic is heated.

Reingruber, E, M Himmelsbach, C Sauer and W Buchberger. 2010. Identification of degradation products of antioxidants in polyolefins by liquid chromatography combined with atmospheric pressure photoionisation mass spectrometry. Polymer Degradation and Stability 95:740-745.

New chemicals – with unknown toxic properties – are present after heating commercial polypropylene plastics during manufacturing.

The chemical composition of an everyday plastic could be more complicated than what a list of raw ingredients would suggest, report a group of Austrian chemists.

Their discovery concerns chemicals that manufacturers add to stabilize polypropylene (PP) plastics. The synthetic antioxidant additives break down when exposed to high temperatures typical of the manufacturing process, especially when they are combined with a common mineral filler called talc.

The results of this study add to the body of knowledge about chemicals found in everyday plastics. The findings could be used to more thoroughly assess the implications for environmental and human health.

Antioxidants are added to protect the structure of the plastic. They are designed to react quickly with oxygen, sacrificing themselves to protect the PP chemical chain.

The discovery of the new chemicals is of concern since they may occur in commercial products where they could migrate out of the plastic and potentially into humans. Talc-filled PP plastic is typically found in car parts, household appliances, and building materials.

The researchers did not measure the toxicity of the newly discovered chemicals, but their molecular similarity to the controversial product additives BHT and BHA suggests that they merit further study. While still widely used, the synthetic chemicals BHT and BHA have known health effects. They are used as antioxidants in many products, including food, cosmetics, pharmaceuticals, plastics and some petroleum-based greases and lubricants. BHT has been shown to cause mutations, tumors and endocrine effects in test animals. It has been responsible for allergic responses in people. BHA can also mimic the female hormone estrogen.

The researchers tested six commercial antioxidant additives, four of which had structures similar to BHT. In the presence of heat and talc, the additives lost parts of their chemical structures in predictable ways. This predictability means that chemists might be able to anticipate what will happen when new additives are exposed to heat and design for safer breakdown processes.

The chemists showed that although most of the pure additives were stable at 239 degrees Fahrenheit, all of them broke down when talc was present. Some also broke down when blended with the PP. PP generally melts above 266 F. If the additives were blended into melted plastic, the high temperature would lead to their degradation, and thus, the new low-molecular-weight chemicals.

The observed decrease in molecular weight could lead to faster migration out of the plastic. This question and the issue of toxicity could be resolved by further study.

So it might be an issue of dealing with the devil you know versus the devil you don't. At this point, I'm not sure if there is enough data to conclude whether silicone is safe for food yet or not.

Just a note: I've been using different sized freezer containers (made from polyethylene plastic) as chocolate moulds. They're not ideal since you just end up with a bar, which if too big, needs to be cut or chopped into smaller pieces. But they work in a pinch and it was the best I could find on such short notice. It would be nice to have a regular chocolate bar-shaped mould which has the marked sections for breaking off pieces or some sort of mould where you can pour bite-size pieces. I've seen these for sale on various websites in those two materials (polypropylene plastic and silicone) as mentioned above.

 

[Aliana]

Just a note: I've been using different sized freezer containers (made from polyethylene plastic) as chocolate molds. They're not ideal since you just end up with a bar, which if too big, needs to be cut or chopped into smaller pieces. But they work in a pinch and it was the best I could find on such short notice. It would be nice to have a regular chocolate bar-shaped mold which has the marked sections for breaking off pieces or some sort of mold where you can pour bite-size pieces. I've seen these for sale on various websites in those two materials (polypropylene plastic and silicone) as mentioned above.

I have been using bite-sized muffin tins (something like these http://www.williams-sonoma.com/products/usa-pan-traditional-finish-mini-muffin-pan/) and have found tiny paper wrappers that just fit inside the molds - they look like mini cupcake wrappers. I pour or spoon the melted chocolate into the paper/molds and put in the fridge to set. The paper pops right out of the mold. I am not sure what my tins are made out of since I found them in my Mom's kitchen stash when she moved. So - just to be on the safe side I use the paper wrappers. This has worked really well so far and makes clean up much easier.

The only problem is that I use coconut oil in my chocolate, so have to keep it cold if i take it anywhere, or I have a mess of chocolate. Generally I keep them in the refrigerator for use at home.

 

[monotonic]

It could be edifying to look at how silicone molds are manufactured, because even if the silicone itself isn't toxic, other chemicals used to make it may be.

 

[Oxajil]

How about a 100% stainless steel muffin pan?
I found this one for example: _http://www.marmeesbreadmarket.com/store/index.php?main_page=product_info&products_id=100

You could also look for cast-iron muffin pans, on amazon for example. Be sure it's safe!