I want to buy a vacuum sealer for food. The vacuum bags do not have a hechsher. Normally, I buy ziplock bags that are OU. To keep this general, I am hoping someone can elaborate on the reason and ruling behind needing approval for food storage containers. If the food is always room temperature or colder when putting into the bag, does that make a difference? I imagine the law is based on the transfer of taste from the bag, which seems to imply the food going into the bag is warm, because otherwise the transfer would not occur.

After looking at star-k's list of items that don't need approval, which includes plastic bags, I wonder why OU feels they do need approval.

  • 2
    Letting something liquid sit in a container for 24 hours is kavush ("pickled") and can transfer taste as well sometimes.
    – Double AA
    Commented May 21, 2013 at 4:47
  • 3
    If someone <strike>asks</strike> pays OU to certify shirts, why shouldn't they? Commented May 21, 2013 at 5:50
  • 1
    Do they say they need hashgacha? Commented May 21, 2013 at 5:50
  • @ShmuelBrin Because that would be mean. They should explain that shirts don't need certification (assuming that is the case) and not take money from people who don't know any better.
    – Double AA
    Commented May 21, 2013 at 6:10
  • Maybe $ $ $ $ $
    – Yehoshua
    Commented May 21, 2013 at 7:32

4 Answers 4


One could dream up some remote possibilities, but in short, it's not:

The OU feels that Ziploc bags need approval


The Ziploc company decided they'd sell better with OU approval

There's an OU shiur (I believe it was a session for women in professional kashrus, and it featured Rabbi Yoel Schoenfeld) where someone asked about an OU on bottled water. The rabbi replied it was basically a marketing decision on behalf of the water company - if they want an OU, okay the OU will go in, check it out, and give it to them! No one was saying it was halachically necessary - but it sells better that way.


(I hereby authorize myself to quote myself verbatim, and indemnify myself from any and all copyright claim against myself.)


From the Star-K:

"Quite frankly, we were astonished to learn of the rather extensive use of stearates and other tallow based chemicals in the production of plastic food-contact materials. These chemicals may be added to plastics in various formulations at concentrations as high as two percent with the intent and knowledge that they will migrate to the surface, thereby interacting with the foods they contact. Due to this migration and interaction the FDA requires that all additives used in plastic food-contact materials be of an acceptable food grade quality."


  • I wish the Star-K would be more clear regarding the permissibility eating foods kept in those plastic items. As it stands, they leave it up to the reader to interpret what they mean by saying that it's a "problem" to be solved.
    – Fred
    Commented May 21, 2013 at 19:18

The OU has an extensive list of non-food items that do not need a hechsher for Pesach. Included in the list are plastic bags and containers, and aluminum foil wrap and pans. I assume that this can be extended to year-round as well. A detailed discussion of these products can be found on the OU website here.

Star-K also has a list of foods and items that don't require a hechsher. Included are plastic bags and aluminium tins.


they don't need a hechsher, except maybe for pessach (where the starch which might be used is a problem)

  • 3
    Without a source this isn't a very useful answer, as we don't know who you are! Nothing personal...
    – Double AA
    Commented May 21, 2013 at 11:04
  • Source: Dayan Zimmerman
    – jekishboy
    Commented May 21, 2013 at 18:58

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