What you see: Bubbles on the plastic film sealing up your yogurt.
What it is: Probably a harmless processing issue.
Eat or toss: If the yogurt otherwise looks and smells fine, give it a taste. If it tastes normal then you’re good to go.
Is yogurt still safe if there are “bubble prints” on the seal?
When I saw these odd bubble-prints on the clear plastic film sealing my yogurt, I couldn’t help but fear the worst. Could this be the work of fizz-generating, destructive microbes (which wreaked such havoc on some Chobani yogurt that the company issued a voluntary recall in 2013)?
Nope, food scientist Nicole Martin told me. If there were problematic microbial growth, I’d probably also see a bloated package, or maybe even a seal busted by pressure from yeast-produced gases; the yogurt would also probably smell and taste strange.
So, phew! The bubble prints on my yogurt’s seal, Martin told me, probably came about because of a minor fluke when the yogurt was pumped from a tank into the plastic cup.
“That looks just like a processing issue to me,” said Martin, associate director of the Milk Quality Improvement Program at Cornell University. “Like it was at the end of the tank and so they had extra foam on the top or they had a little too much air in the process.”
Martin also pointed out that bacterial culture used for yogurt like this doesn’t produce a bubble-making gas; it only generates lactic acid, which is essential for yogurt making. So, absent any signs of contamination, the bubbles must have been the result of a mechanical process, not a biological one.
Break out the bubbly! The yogurt is fine!
