What if mayonnaise with olive oil has a date best when used by Sep 10?

Here's what you can do:

1. Check the Appearance: Before consuming the mayonnaise, inspect its appearance. If it looks curdled, discolored, or has an unpleasant odor, it's best to discard it, even if it's within the "best when used by" date.

2. Taste a Small Amount: If the appearance seems okay, take a small taste to assess the flavor and texture. If it tastes rancid or has any off flavors, discard it.

3. Consider Storage Conditions: The "best when used by" date assumes proper storage conditions. If the mayonnaise with olive oil has been continuously refrigerated at the recommended temperature (usually between 35-40°F or 2-4°C), it's likely still okay to consume. However, if it has been left at room temperature or exposed to heat, discard it.

4. Use Common Sense: Ultimately, use your best judgment. If you're unsure about the quality or safety of the mayonnaise, it's better to err on the side of caution and discard it. Food safety is paramount.