Can you shave a few milliliters off the amount of detergent that you use in every load of laundry and still get your clothes as clean? You probably can, but we’re curious after checking out this slight change in the amount of Tide detergent in a bottle while the number of loads per bottle remains unchanged.

“I noticed this today at Wal-Mart,” she writes. “New and old packaging side by side. Maybe the lid size changed…? Couldn’t find any evidence on the bottles.”

The bottle change makes each theoretical serving of detergent .6 ounces lighter. Does that make a difference? Is there less detergent in the bottle, or is it slightly more concentrated than it used to be?

Hmm. We’re not sure. We dropped Procter & Gamble an e-mail, and will update this post if we hear anything from them.

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