In the same week that Pepsico pulled its SunChips compostable PLA package off grocery store shelves, Stonyfield Farm announced its new PLA yogurt cups. And while I pretty much dissed the SunChips bag in my post last week, I am feeling a little warmer towards Stonyfield’s effort. Not hot. Not warm and fuzzy. But while I think there are better options, I have to concede that the new yogurt cup is a step in the right direction, and I’ll tell you why. (Of course I’ll tell you why. That’s the purpose of this blog.)
Prepare yourself for a long post. There’s a lot of information here, but I think it’s all important. So get yourself a snack and settle in.
PLA vs. Polystyrene
Stonyfield’s new yogurt cups replace the multipack cups that were previously made from polystyrene. That’s right. While their larger sized and single-serving containers are made from #5 polypropylene plastic and can be returned for recycling into Preserve toothbrushes and razors, the 4-ounce multipack cups were #6 polystyrene (the same kind of polymer from which Styrofoam is made) and could not be recycled.
Not only is polystyrene not recyclable, but it’s also pretty toxic stuff. Styrene, the basic building block of polystyrene, is classified as a possible human carcinogen by the EPA and by the International Agency for Research on Cancer (IARC). And when heated, it can leach chemicals into food. But, you might say, I don’t heat my yogurt! Actually, it’s already been heated in the container. But I’ll get to that part later.
PLA (polylactic acid) is made from plants — mainly corn. And as I mentioned in my SunChips rant, corn is a problematic crop. I wrote:
Industrial corn farming requires huge amounts of petrochemical fertilizers and pesticides. And growing corn in this country is fraught with other environmentally and socially damaging practices. From monoculture farming that destroys diversity to genetically modified organisms that ensure the monopolization of the food supply by large corporations, industrial corn is a troubling business.
What’s more, PLA is produced by Cargill, the same company that gives us other corn goodies like high fructose corn syrup, and which also trades in petroleum and other fossil fuels. How, then, is this PLA any better than the polystyrene it is replacing?
How Stonyfield’s PLA is Different
Stonyfield did not go into this process ignorant of the environmental problems associated with PLA, and they addressed these issues in a Webinar that I attended last week. First, Stonyfield contracts with the Institute for Agriculture and Trade Policy for Working Landscape Certified corn. That means that the farmers who grow the corn agree to:
* Grow only non-Genetically Modified (GM) crop varieties
* No continuous annual crop production on same acreage
* Soil testing to assure that nutrients are used efficiently and are not likely to leach or run-off
* No use of chemicals that are known human or animal carcinogens, including atrazine
* Use of cover crops to minimize soil erosion
* Creation of a farm plan that includes information on biodiversity, energy use and greenhouse gas emissions.
Now, the corn Stonyfield actually receives is not necessarily the certified corn. The IATP system is an offset program. Stonyfield contracts for the amount of certified corn it needs, and that amount enters the system, whether Stonyfield or some other purchaser gets it.
Most people are surprised to know that PLA products, like petroleum-based plastics, contain additives that can leach, especially when heated. (Like I said, I’ll get to that later.) And Stonyfield’s containers are made from 93% PLA, 4% titanium dioxide — a colorant, and 4% other additives. It’s that 4% that we, and Stonyfield, are worried about. Here’s the thing…
A BIG thing…
A thing that I have ranted about before, but for those who are new here and missed those rants…
NO ONE KNOWS what additives plastics manufacturers put in their plastics. Not the consumer, for sure. But not even the companies that contract to have their containers made. Stonyfield doesn’t know what chemicals are added to their PLA containers because no plastic manufacturer will disclose that information. In fact, the rep who presented the webinar stated, “Plastic is the most secret industry you can imagine.”
Knowing that those additives could be a problem, the company took steps to mitigate the situation. Since it couldn’t know what was in the plastic, Stonyfield decided to identify and ban the toxic chemicals they did not want. So it hired the environmental consulting firm Pure Strategies to come up with a plan. I spoke with Ken Soltys from Pure Strategies who explained the steps the company took to ensure the safest chemicals were added to the PLA.
1) PS identified the three types of additives that would be needed to make the yogurt cups: an impact modifier to soften the plastic, since unmodified PLA starts out very brittle (Turns out, impact modifiers are another set of petroleum-based plastics. So yes, there is a tiny amount of petro-plastic in the Stonyfield container.), a heat stabilizer, and a melt strength additive to make sure the PLA doesn’t sag or crumble in the machine when heated. Then, knowing what additives would be needed, PS identified all the chemicals available to serve those functions and from that list, specified the toxic chemicals that could not be used.
2) PS identified 2,500 other “red list” chemicals — those that had been determined to be toxic (carcinogens, mutagens, reproductive toxicants, and endocrine disruptors) by several different U.S. and international agencies — and banned all of those chemicals from Stonyfield’s packaging.
3) PS flat out banned certain classes of chemicals: phthalates, polybrominated materials, PVC, and BPA. According to Ken, even if those chemicals were not directly added to the plastic, they could still end up in it if the manufacturer reused molds that had been previously used for other plastics. So Stonyfield’s packaging had to test free of those contaminants.
Is It Safe Enough?
Here’s the thing: Knowing what’s not in something doesn’t tell us what is. It’s great that Stonyfield went to such lengths to ensure that known toxic chemicals were not added to their product. But the fact is that new chemicals are released onto the market constantly, and sometimes what we don’t know can hurt us. That is why (watch me climb up on my soap box now) I. Don’t. Eat. Food. In. Plastic.
Ken acknowledges that the system we have in place is not perfect and that if the FDA were truly protecting us, then firms like Pure Strategies would not be needed. But until the government requires plastics manufacturers to disclose all of their additives, steps like Stonyfield has taken are the best companies can do if they want to package food in plastic.
A Question of Heat
As I mentioned before, plastics leach the most when they are subjected to heat. And while you are probably not going to put a plastic container of yogurt into the microwave, Stonyfield’s yogurt cups are filled while the yogurt is still hot. 100°-108° F, to be exact. Why? Because that is the temperature needed to grow the little bugs that make the yogurt. The cups are filled with the hot milk as well as the yogurt culture, and the yogurt sets right there in the plastic cups. If there are chemicals that can leach from the plastic, that’s the time they’ll do it.
Not all yogurt companies fill their yogurt cups with hot milk, but all the big ones do. Straus Family Creamery, a local yogurt company I visited and blogged about last year, vat sets their yogurt. The milk is cultured in big stainless steel vats, and the plastic yogurt cups are not filled until the yogurt is finished and has been cooled to 40°F. As you can imagine, Straus makes its yogurt in much smaller batches than Stonyfield. It’s not attempting to outdo the Yoplaits and Dannons of the world.
Waste — Downstream vs. Upstream
Unfortunately, right now there is no way to recycle Stonyfield’s new PLA containers. Unlike Pepsico that insisted its SunChips PLA bag was compostable (despite customer reports to the contrary), Stonyfield is making no such claim about its yogurt cups. Instead of composting, Stonyfield is looking at feedstock recovery — recycling the containers back into PLA pellets that can be reused to make new containers. It’s recycling which actually closes the loop, unlike the downcycling that happens with petroleum-based plastics. And there are two facilities where PLA is recycled: one in Belgium and one in Nebraska. But Stonyfield can’t do it yet. They have a lid problem.
Because the lid of the Stonyfield yogurt pack is not yet made from PLA but metalized PET (#1 plastic), the PLA recycling facilities will not accept it. Creating a new lid and developing a take-back program for the containers are priorities for Stonyfield. But the company wanted to replace the polystyrene cups sooner than later and opted to release a less than perfect solution now, which they feel is at least a step in the right direction.
What’s more, Stonyfield says that the upstream benefit of the new packaging outweighs the downstream waste issue. In a life cycle assessment performed by Roland Geyer from UC Santa Barbara, PLA outperformed polystyrene in the areas of greenhouse gas emissions and human toxicity. In fact, the new cups have 48% lower global warming potential than the old ones. And that is why Stonyfield is comfortable releasing them without a recycling infrastructure in place yet.
The Wrong Comparison?
Here’s where I get all hardcore on you and where I ask for your opinions. I will certainly concede that the new packaging is superior to the old. And it has the potential to be even better, once the lid problem is solved and take-back program in place. But…
What if we didn’t need a disposable package in the first place? There are already two options that negate the need for plastic packaging. The first is not available everywhere. But the second… anyone could do.
St. Benoit is a small yogurt company in the Bay Area. It sells its yogurt in returnable glass and ceramic containers. Just like glass milk bottles that are available in some places and can be returned to the store, St. Benoit’s containers carry a deposit which is refunded to the customer when the jar is returned. There’s no extra fuel used to return the container to the store because customers just bring them back during their regular shopping trips. Zero waste (except for a plastic security seal around the lid).
But even better than buying someone else’s yogurt in any kind of container: Make your own!
Do you know how easy it is to make yogurt yourself? It’s so simple that I achieved perfection the first time I tried. I made it in a Thermos. Here are the homemade yogurt instructions I followed. All that is required is milk, a tablespoon of yogurt from a previous batch (or commercial yogurt if it’s your first time), a thermometer, and a thermos. Fruit or sweeteners are a plus. And you get the whey along with the yogurt, which can be used in all sorts of ways. (Pun acknowledged but not necessarily intended, unless you like puns.)
The Bottom Line
Stonyfield yogurt is a good alternative to Dannon or Yoplait or other big brands because it’s organic and because the company is doing its very best to mass market its product sustainably. If the choice is between a non-organic yogurt in a plastic container or an organic yogurt in a bio-based container, I’d choose the latter. And hopefully many other conventional yogurt eaters will make that switch.
But let’s not forget that we do have other choices. We don’t have to opt for the mass market.
So what do you think?