Dairy Ingredients

• As the name implies, homemade Irish cream contains dairy ingredients. Sweetened condensed milk thickens and sweetens it, while heavy cream gives it a smooth, rich mouthfeel. Before they are sold, commercially available dairy products are pasteurized to eliminate harmful bacteria, but they still have to be stored properly. The U.S. Food Safety Working Group reminds consumers that pasteurization does not mean that milk can be left out of the refrigerator, especially after it has been opened.

Raw Eggs

• Some recipes for homemade Irish cream call for raw eggs. Including eggs will increase the richness of the final product, but will also increase the risk of food-borne illness such as salmonella. The U.S. Food Safety Working Group recommends using pasteurized eggs or egg substitutes instead of unpasteurized raw eggs. Using pasteurized eggs or egg products will not allow you to store your homemade Irish cream outside of the refrigerator, but they will ensure that your liqueur does not start out with harmful bacteria.

Whiskey

• A small study done by microbiologists at Rockefeller University in 2008 suggests that using raw eggs in beverages such as Irish cream and eggnog is safe because the alcohol kills any bacteria present in the eggs and dairy products. While this study does explain why there are not serious spikes of salmonella in the winter months when homemade eggnog is most prevalent, it is not conclusive enough to suggest that it is safe to store alcoholic beverages such as Irish cream at room temperature.

Shelf Life

• Homemade Irish cream does not include the same preservatives and stabilizers present in commercial versions. To determine how long your homemade Irish cream will last, check the expiration dates of the ingredients you use. Consume your Irish cream before the soonest expiration date of those ingredients. For example, if the cream expires 14 days from the date you make your Irish cream and the eggs expire 10 days from that date, consider the eggs' expiration date to be the date by which you should finish your homemade Irish cream.