Given the thousands of cheeses in the world, the number of possible cheese ball recipes is all but unlimited. Still, most conform to the same broad description. One or more strongly flavored cheeses is finely shredded, then mixed into a base of softened cream cheese or a similarly soft, spreadable cheese. Fresh herbs, spices, dried fruits and seeds or nuts can all be added to provide complementary or contrasting flavors, and some recipes add a splash of alcohol. The finished ball is usually rolled in seeds, crushed nuts or freshly ground spices, to provide a visually appealing exterior.

If you purchase your cheese balls at the supermarket, their shelf life is relatively straightforward. They're manufactured in tightly inspected production facilities, then packaged in airtight plastic and -- usually -- stamped with a "best before" date that's weeks or even months in the future. This is intended to tell you how long the cheese ball will retain its best freshness and flavor. The date is a reasonably reliable guide, but it assumes the cheese ball has been kept refrigerated throughout its life. If it was permitted to warm to room temperature at any point, it can spoil before its freshness date expires. Use common sense, and be alert for any signs of mold, fluid discharge or unpleasant odors.

Your homemade cheese balls don't have the benefit of sterile packaging and production, so they won't last as long as a commercial product. The rule of thumb for cheese balls, dips and similar products is that they'll last as long as your most perishable ingredient. The main ingredient in a cheese ball is cream cheese, which ordinarily lasts for a week or two in the fridge once it's opened. If you've used fresh herbs, diced fruit, cream or other perishable ingredients, the storage life of your cheese ball might be as little as 24 to 48 hours.

Once you unwrap your cheese ball and set it out for guests, your focus should shift from shelf life to food safety. Potentially harmful microorganisms multiply rapidly at room temperature in highly nutritious foods such as cheese, so pay careful attention to the time when you set out your cheese ball. After two hours, any unused portions should be discarded, for safety's sake. Rather than making one large cheese ball, consider making two or more smaller balls or logs and bring them out over the course of the event. Have a steady supply of clean or disposable utensils, and change them as often as needed to prevent contaminating the cheese.