Buzz
For some unknown reason, certain people have a habit of hoarding bottles of expired salad dressing. Personally, I can’t help but notice that a recently expired bottle of Trader Joe’s Green Goddess dressing in my fridge might just be evidence of me slowly turning into my grandmother—one food item at a time (the cheap bologna package only adds to this theory).
But what about those expiration dates? Do they hold any real significance, or are they just part of a clever marketing tactic to encourage us to purchase more salad dressing? To get to the bottom of these burning questions, I reached out to Dr. Donald Schaffner, an extension specialist in food science and a distinguished professor at Rutgers University.
The first thing I asked was how seriously we should take those printed dates. In response, Dr. Schaffner shared, 'I think you are correct in assuming that the dates are likely conservative in most cases. Keep in mind that the food company’s priority is to ensure you have a positive experience with their product, so they might err on the side of quality.'
The good news is that the quality of salad dressing can often be assessed by taste. If you come across an expired bottle of dressing, whether in your parents’ fridge or your own, use your senses to check if it smells rancid, and discard anything that doesn’t taste like the dressing you love. 'Salad dressings often have a high fat content, making them prone to oxidation,' explained Schaffner. 'It might not just be a rancid smell; it could have an off-flavor. I remember once tasting expired dressing and swore it tasted like cardboard. Turns out, 'cardboard' is a real term for certain off-flavors.'
Flavor isn’t the only concern, but thankfully, when it comes to bacterial growth, salad dressing is formulated to work in our favor. 'Most salad dressings are designed to resist harmful microorganisms,' Schaffner noted, 'and they’d actually kill any bacteria present.' It's unlikely anyone could contaminate their own dressing. However, it's still wise to toss any dressing that looks a bit...fuzzy. 'Mold formation is certainly possible. Molds tend to be more resilient than bacteria and some can even produce toxins. It's best to discard any dressing with mold. Unlike bread, you can’t just cut off the moldy part of the dressing.'
While unopened bottles past their expiration date may still be safe, it’s impossible to give a universal time frame for all dressings. 'Every product is different,' Schaffner explained. 'The manufacturer is your most reliable source since they’ve likely conducted extensive shelf-life studies. The storage conditions also play a role. Was it kept in direct sunlight, warming up on a shelf, or in a cool, dark basement? Cooler temperatures and less light help preserve quality.'
The most reliable way to check? Give it a sniff and a taste. 'If it’s unopened and past its best-by date, try a little bit,' Schaffner advised. 'If it tastes fine, then it’s good to go! Due to the way these products are processed, it’s very unlikely that mold would develop upon opening. But depending on how long it’s been past the date and how it was stored, it might taste oxidized or just 'off.' So, the next time you visit your parents, do a little taste-testing of their expired dressings. You might discover perfectly fine raspberry vinaigrettes, or ranches that taste like cardboard. It won’t be pleasant, but at least you’ll know which ones have 'off-flavors.'
This interview was lightly edited for clarity. Updated 3/2/2022 with new details.
