Just about any dessert or pastry tastes even better when filled or topped with a thick dollop of freshly whipped cream. Whipping cream contains at least 30% butterfat and its volume will double when whipped. The cream can sour and spoil if it is stored in a place that is too warm, or if it is past its expiration date. Soured cream should not be ingested as it poses bacterial risks as well as an unpalatable taste.
Check the expiration date on the carton of whipping cream. If it's kept closed in the refrigerator at or below 40 degrees F, the cream may last for a week past its printed expiration date and is usable as long as it does not taste or smell sour.
Smell the whipping cream. Soured cream has a distinctive smell as bacteria starts eating away at the components and the milk fat starts to oxidize. Spoiled cream smells rancid, whereas usable whipping cream has a mild, milky smell.
Dip a finger into the whipping cream and taste a portion of it. Soured cream tastes bitter and is unusable in recipes calling for fresh whipped cream. Do not take any more than a very small taste if the cream is sour to prevent ingesting any harmful bacteria.