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Soy milk expiration dates- myth or reality or marketing ploy

I usually buy soy milk in the 64 ounce container- I notice on most brands that it states the product should be consumed within 7 days of being opened- I only use it in my breakfast cereal so one of these containers can last me about 3 weeks.

I've gone well beyond 7 days after opening and have not noticed any souring, decline in quality, etc...

And I'm still here to write this!!!!!! Is this a ruse to get us to buy the product more frequently?
Am I putting my life at risk????

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  1. My experience is similar to yours. I only use it baking, and so can have a container of soymilk around for a very long time. It does go bad eventually, getting chunky, but it takes several weeks. Hasn't killed me (or my guests) yet!

    1. It's simply a cover-your-ass recommendation (it's not an "expiration date"). In our litigious society they have to give some kind of warning that eventually the product might go bad (and I think the government requires them to do so) so they pick a date they think is absolutely "safe."

      I think this is particularly true of products in aspectic packaging, because they don't trust that people will realize that even though it was okay on in the cupboard for months, the contents is susceptible to spoilage after it's been opened.

      1 Reply
      1. re: Ruth Lafler

        As someone who regularly forgets things in the fridge, I always appreciate a best before date to help me remember when I opened the darn thing. When you have to figure out what year it is from, you know you've gone to far !!!!

      2. My husband, bless him, is a fanatic about expiration dates and routinely throws out perfectly good food and drink when that date rolls around (much to my chagrin).However, he won't go near soy milk and I've successfully kept cartons in the fridge, at least 3 weeks, probably more, with no ill effects or noticeable degradation in taste or quality. It's like yogurt to me, which I am comfortable eating up to a month past the exp. date.

        1. There are expiration dates that you should abide by. Then there are "sell by" and "use by" dates. Those are, as Ruth said, cover-your-ass dates! There are also "best before" dates. I had to laugh when I saw on a cracker box a "best before" date of Mar 16 08. C'mon, how did they come up with that exact date?

          3 Replies
          1. re: danhole

            Because they have done stability studies and come up with a time frame within which they have evidence that the product will be fine. It may or may not be outside of that, depending on a number of factors.

            So let's say their stability study shows 12 months under all conditions, whether you keep it in a cool dark place or in the back window of your car during a Texas summer. They add 12 months to the date of manufacture, which for a 12 month shelf life would be Mar 16 07.

            1. re: JonParker

              Amazing info! So now I know the date the crackers were manufactured. Thanks.

              1. re: danhole

                Well, you only know the date of manufacture if you know what the stability data shows, which you generally don't. If it's got an 18 month shelf life the date of manufacture would be different.

          2. I, too, keep my soymilk for 2-3 weeks, using it only on my breakfast cereal (and then not a lot of it, either). You can add me to the "still alive and kickin'" club!

            1. I ignore all expiration dates. If something gets old enough in my fridge it mutates a pair of legs and manages to get out of the ref and run away. If not, it is eaten.

              1 Reply
              1. I've often wondered how you're supposed to tell when soymilk is going off, it doesnt smell!! I have had soymilk go lumpy on me though, but both times this happened BEFORE the expiry date, and a very short time after opening. I never noticed the 7 day window on mine, oops! I mostly use it in coffee, so same goes (but i buy it in 1 litre)

                I will eat yogurt past it's sell by, cheese, tofu (within a few days) etc....pickles and salad dressings can stay in my fridge for ages . I don't eat any meat products, but this would probably be one of my cut-offs for safety.

                We have a fanatic at work like swissgirl's DH....and it pains me to watch perfectly good (and in my opinion safe) food get tossed every few days because it's one day past the date on the package. Including stuff like bread up in the freezer. I consider this highly wasteful.

                1 Reply
                1. re: im_nomad

                  On a tangent, I have an unopened container in the fridge with an expiry date of February 5. From the sound of, I should simply look for lumps, and if none, feel free to use in my favorite butternut squash soup recipe, yes?


                2. i find it varies by brand though generally soy milk does last long. For example, Soy Nice goes bad faster than Natura and Earth Shake (I'm Canadian so these brands may be unfamiliar to you). Also, I think, if the milk is in the cold part of the fridge, and if the lid is on tight, and if the box gets opened a lot or not, affect the shelf life.

                  5 Replies
                  1. re: chocabot

                    Add to that, Chinese brand soymilks from local tofu factories go bad in what seems like minutes! I don't think I've ever got much more than 4 days out of a carton... First they get really beany and then parts start to solidify.

                    1. re: chocabot

                      Free soy cheese! And you're complaining!

                      1. re: Sam Fujisaka

                        LOL - oh yes.
                        Please tell me how to use the smelly stuff and I'll retract my statements!

                          1. re: chocabot

                            In all seriousness now, when I lived in Bolivia and milk was completely unprocessed, the milk would go bad, smelling awful. We would dump the coagulated mess into a cheese cloth and hang over the sink overnight. Next day we had a thick, sweet, good smelling spreading cheese. Doubt it would work with soy milk, but it might be worth trying.

                    2. I'm with Sam Fujisaka. I use soy milk in my tea in the morning, but not for much else. I only throw out a carton when it curdles on contact with the tea.

                      Meanwhile, I've had the same soy milk curdle in coffee but not in tea. Has anyone else seen this? I always wonder if there's something in coffee that soy mild doesn't like.

                      1 Reply
                      1. re: Kagey

                        i'm guessing it's the acid content of the coffee. definitely higher than tea.

                      2. I wonder about this after I started making my own stone ground soymilk and tofu. My experience with the China town soft soy curds (Dou Hua, can't get that in Western food stores) and certain brands of Tofu were always that they don't keep well, and you definitely will smell the sourness when it's gone bad.

                        So, I made soymilk and tofu from various types of soybeans about 10 times now, and each time it seems that they keep forever without spoiling! Some of the beans I used were organic, but there were times when I used regular soybeans, yellow, black, black with green center....All have held up quite well.

                        So, I guess I'm also puzzled about the expirations issues. What's making the difference?

                        2 Replies
                        1. re: HLing

                          Well sorry to complicate things but I have been making homemade soymilk for more than two years now, about 2 quarts every four days as I use it. I've had homemade stuff sit around for 9-10 days and at that point I can begin to detect a sour taste/smell that gets worse with time. If you keep the containers you keep it in very clean/sterile this isn't a problem but I tend to use plastic containers that are hard to clean and I try to use soap as sparingly as possible as the plastic has a tendency to absorb the flavor of the soap. Also the vast majority of commercial soymilk has salt or other preservatives that help to preserve the opened shelf life. Thankfully in either case you're not going to get ecoli/salmonella from soymilk.

                          1. re: Professor12

                            "...Also the vast majority of commercial soymilk has salt or other preservatives that help to preserve the opened shelf life. ..."

                            That's interesting to hear that salt can act as a preservative. I wonder, along the same line, if the Nigari ("bitter"- mineral from the deep sea - the Japanese use as coagulant in tofu making) that i use to make tofu can act as a preservative somewhat?

                            I'm curious to hear what kind of soybeans you use to make soymilk, as I'm also starting to wonder what the commercial soymilk makers are using.

                            AS far as container goes, I started to use the heavy duty glass bottles (that Ronnybrook milk come in, as well as some of the salad dressing in the supermarket), and I've found that it keeps especially well. I know the plastic dilemma, and am phasing it out as much as I can now.