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Saran Wrap Isn’t What It Used To Be


In the 1960s, I used to help my mother in the kitchen and learned how to cook. I used Saran Wrap to cover plates and bowls, and I noticed that this material was sort of magical. It stuck to what I wanted it to stick to and wasn’t much inclined to stick to itself. What is this sorcery? You could pull it back to access something in a bowl, then seal it back up again. I was fascinated because it seemed like it was intelligent. I had studied some chemistry but not yet enough to guess the cause for this marvelous behavior.

Plastic Wrap

So what was this wonderful material I was working with? In 1933 a chemist at Dow Chemical was trying to develop a new dry cleaning solvent. He noticed that certain beakers and glassware were hard to clean. They had a residue that was hard to scrub off. Investigation revealed a new substance, a new polymer that was named polyvinylidene chloride or PVDC.

It was found that, among other things, PVDC made a tough and durable clear coating. During World War 2, virtually every U.S. aircraft was coated with PVDC to help protect it from the elements. At the end of the war, hundreds of companies in the U.S. got busy looking for commercial applications for the countless marvelous things they had developed for the war effort. Somebody at Dow realized that PVDC would make an excellent food wrap. And excellent it was, as you will see later. Production methods for forming PVDC into a very-thin film were developed. The CEO of Dow decided to name it after his wife and daughter, Sarah and Ann: Saran.

The product was introduced in 1949 and was an almost overnight success. This is the stuff I was using in the 1960s. Towards the end of the 1960s, Dow’s patents expired and other companies began producing PVDC food wrap, like Glad Wrap. They were all just copies of Saran Wrap.

From the 1990s forward, I didn’t use much plastic food wrap until I began to work in a restaurant in 2012. There, I used plastic food wrap all the time and immediately noticed that it behaved differently from what I remembered. Sure, it worked, but it frequently refused to stick to some things and it was eager to stick to itself. This is not what I remembered. After opening and closing a covered bowl, the plastic wrap would become wrinkly and refused to stick to anything. I covered a mixing bowl full of diced onions with this plastic wrap and placed it in the cooler. Soon, the cooler smelled strongly of onions. What? That’s not supposed to happen. What is this stuff? Maybe some kind of cheap imitation of Saran Wrap?

Time passed, I finally did some digging on the Internet, and immediately found the answer. Through the 1990s, chlorinated polymers like PVDC became an increasing environmental concern. In 2004, all the makers of PVDC plastic wrap switched to ordinary low-density polyethylene (LDPE). Polyethylene is cheap and easy to make into a thin film. But there are problems. Big problems.

First of all, polyethylene is a low-friction, non-stick kind of polymer. This is why milk bottles are made from it. Polyethylene film doesn’t stick to anything, nor itself. Today’s polyethylene plastic food wrap is coated with a moisture-activated adhesive to make it “cling”. At best it clings to certain things but not others, and it eagerly sticks to itself, making it hard to work with.

Secondly, the adhesive quickly wears out so opening and reclosing a bowl covered with modern plastic wrap is something you might be able to do once but not repeatedly, like you can with PVDC film.

Thirdly, polyethylene film is around 3,000 to 4,000 times more permeable than PVDC film. Oxygen is the main culprit that causes food spoilage. For every molecule of oxygen that a given area of PVDC film lets through, polyethylene film lets through 3,000. The consequences of this are obvious. It also explains the experience I had with onions stinking up the cooler. That wouldn’t have happened with PVDC film. In fact, certain meats are still packed with PVDC film because polyethylene film can’t do the job.

The bottom line for me is I was pleased to discover that my memories from the 1960s were pretty accurate. However, I was not pleased to discover that the plastic film I use today is inferior in terms of performance and user friendliness, and there’s no way to fix it.

Today’s plastic wrap looks like classic Saran Wrap, but it ain’t. It’s not even close.

6 Comments

  1. V. T. Eric Layton

    Yup. Things change. Those fabulous things from yesteryear, like radium tablets, red dye #2, and DDT, often are found to be dangerous to man and environment, so… changes are made. We end up with costlier things that don’t work as well, but someone is making a decent buck off of it.

    I remember that “miracle” Saran Wrap from when I was a kid. Nowadays, though, I buy the cheapest no-name plastic wrap in the stores. I only use the stuff to wrap up and freeze individual servings of meats (hamburger, beef cuts, chicken breasts, and pork tenderloins) that I buy in bulk. It serves that purpose well and is much less susceptible to “freezer burn” compared to foil, which is also a Helluva lot more expensive.

    • Phil

      Yep, that’s how it is. Hopefully, someone will come up with a polymer with the characteristics of PVDC that’s not a chlorinated polymer or other environmental problem.

      And DDT works great! I used it in the 1960s. It just has certain, uh, problems. It’s a shame because if DDT wasn’t such a problem and was still usable, malaria would be a much smaller problem in the world.

      The Red #2 controversy has never been proven one way or the other. It’s a natural substance only banned in the U.S.A., but is the red dye of choice in Europe, Canada, and the rest of the world. Ironically, evidence is mounting against the substitute we use in the U.S.A., Red #40. A ban on it in the EU is under consideration.

      • V. T. Eric Layton

        Yeah, I remember the “red dye No. 2” fiasco from back then. Another fantastic thing we used to have back then was Chlordane dust*. That shit would kill any and everything with multiple legs. Unfortunately, it was found to be carcinogenic, like MANY other things in this world.

        Medical science doesn’t really understand what cancer is, yet a determination is somehow made that certain thing cause it. Well, guess I’ll step out on the porch for a smoke now. 😉

        *https://en.wikipedia.org/wiki/Chlordane

        • Phil

          Yep, I used Chlordane in the garden, too. Another one was nicotine. My dad used to buy the professional grade pesticides in big glass jugs, Ortho brand, which was a subsidiary of Chevron. It was my job to mix up 4 gallon batches of it in the big sprayer and do the spraying. We had quite a rose garden and many other plants. Some of them grew way taller than I so I was spraying overhead with the mist raining down on me. Nobody worried about stuff like that back then.

          • V. T. Eric Layton

            > Nobody worried about stuff like that back then.

            Because we were much more trusting back then. Most figured that if it was on the market, it must be safe to use. Sadly, that wasn’t always the case.

          • Phil

            Hmm, that wasn’t the case with my parents. The level of personal taking of responsibility was much higher. We didn’t expect to be protected from ourselves.

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