You can pasteurize eggs for ice cream either by cooking them into a custard base on the stovetop or by holding whole shell eggs in a precisely heated water bath. The custard method is the most common approach for ice cream makers because it pasteurizes the eggs while simultaneously building the rich, creamy base you want. If your recipe calls for raw eggs folded in at the end (like a Philadelphia-style variation with egg yolks), pasteurizing the eggs separately in warm water before cracking them is the safer route.
Why Raw Eggs in Ice Cream Need Pasteurization
The FDA specifically names homemade ice cream as a food that carries risk from unpasteurized eggs. About 1 in 20,000 eggs contains Salmonella Enteritidis, a bacterium that lives inside the egg before the shell even forms. Standard grocery store eggs have not been treated to destroy this pathogen. They carry a safe handling label telling you to cook them until the yolks are firm, which obviously isn’t what you’re doing when you stir raw yolks into an ice cream base.
Pasteurization solves this by holding eggs at a temperature high enough to kill Salmonella but low enough to avoid cooking them solid. The target is 160°F (71°C) for a cooked custard, or a sustained lower temperature over a longer period for shell eggs in a water bath. Either way, you get eggs that are safe to use in a frozen dessert that won’t be cooked further.
The Custard Base Method (Stovetop)
This is the gold standard for egg-based ice cream and the method most recipes already use. You’re making a cooked custard, sometimes called a French-style base, that pasteurizes the eggs as part of the process. Here’s how it works.
Whisk your egg yolks with sugar in a heavy-bottomed saucepan. Heat your milk (or milk and cream mixture) separately until it’s warm but not boiling, then slowly pour the warm milk into the yolk mixture while whisking constantly. This step, called tempering, gradually raises the temperature of the yolks so they don’t scramble on contact. Return the combined mixture to the stove over low heat and stir continuously with a spatula or wooden spoon, scraping the bottom of the pan to prevent curdling.
Keep stirring until the custard reaches 160°F on an instant-read or candy thermometer. At this temperature, Salmonella is destroyed. You’ll notice the custard has thickened enough to coat the back of your spoon. If you drag your finger across the coated spoon, it should leave a clean line that holds its shape. The USDA pasteurization standard for liquid whole eggs is 160°F held for 3.5 minutes, but reaching that temperature with continuous stirring is sufficient for a home custard because the mixture spends time climbing through the danger zone gradually.
Once you hit 160°F, immediately pour the custard through a fine-mesh strainer into a clean bowl set over ice water. This rapid cooling stops the cooking, prevents any eggy flavor from developing, and gets the base ready for chilling. Refrigerate the strained custard for at least 4 hours (overnight is better) before churning. A well-rested base produces smoother ice cream with smaller ice crystals.
The Water Bath Method for Shell Eggs
If your recipe requires adding raw yolks directly (some gelato recipes, for instance), you can pasteurize whole shell eggs in a water bath before cracking them. This method works but requires patience and a reliable thermometer, or ideally, a sous vide immersion circulator.
Research conducted for the USDA found that immersing shell eggs in a 135°F (57°C) water bath requires 65 to 75 minutes to achieve a full reduction of Salmonella inside the yolk. At 136.4°F (58°C), the time drops to 50 to 57.5 minutes. The key detail: it takes about 30 minutes just for the center of the yolk to reach the temperature of the surrounding water. So the actual killing time only begins after that initial warm-up period.
A sous vide circulator makes this straightforward because it holds the water at an exact temperature. Set it to 135°F (57°C) and leave the eggs submerged for 75 minutes, or set it to 136.4°F (58°C) for 60 minutes. Without a circulator, you can use a large pot of water on the stove, but you’ll need to monitor the temperature closely and adjust the burner to keep it within a degree or two of your target. A swing of even 3 to 4 degrees can mean the difference between effective pasteurization and undertreatment.
After the water bath, transfer the eggs to an ice bath for a few minutes, then refrigerate. These pasteurized shell eggs stay good in the refrigerator for three to five weeks. When you crack them, they’ll look and behave almost exactly like raw eggs. The whites may be very slightly less firm, but the yolks retain their full emulsifying power.
Temperature Matters More Than You Think
The tricky part of egg pasteurization is that the window between killing bacteria and cooking the egg is narrow. Egg whites begin to set around 144°F (62°C), and yolk proteins start to thicken around 149°F (65°C). Salmonella dies reliably at temperatures above 130°F (54.4°C), but at the lower end of that range, it takes a very long time. Research from the BC Centre for Disease Control found that holding eggs at 130°F (54.4°C) for a full two hours only achieved a partial reduction of Salmonella, making that temperature unsuitable for reliable pasteurization.
That’s why the sweet spot for shell eggs is 135 to 137°F (57 to 58°C). Hot enough to kill the bacteria within a reasonable time frame, cool enough to avoid coagulating the proteins. For the custard method, you’re protected by the sugar and milk in the mixture, which raise the temperature at which the eggs curdle. That’s why a custard can safely reach 160°F without turning into scrambled eggs, as long as you keep stirring.
Why Egg Yolks Improve Ice Cream
Egg yolks aren’t just tradition. They contain lecithin, a natural emulsifier that binds water and fat together into a stable, smooth mixture. This is what gives French-style ice cream its dense, creamy body compared to eggless Philadelphia-style bases that tend to be icier and lighter. The yolk’s emulsifying action helps prevent the ice cream from separating during storage and keeps the texture cohesive as it freezes and thaws through serving cycles. Yolks also increase viscosity in the base, which slows ice crystal growth during churning and produces a finer, smoother final product.
Pasteurizing your yolks through the custard method actually enhances these benefits. Gently heating the proteins causes them to partially unfold and bond with the fat and water molecules in your base more effectively than raw yolks would. This is one reason why a cooked custard base almost always produces better ice cream than a raw-egg base, even setting safety aside.
Buying Pre-Pasteurized Eggs
If the water bath method feels fussy and your recipe doesn’t use a cooked custard, the simplest option is to buy eggs that have already been pasteurized commercially. Brands like Davidson’s sell in-shell pasteurized eggs at most major grocery stores. These eggs have been treated at the processing facility and don’t carry the standard safe handling warning on the carton. The label will state that they’ve been pasteurized. You can use them raw in any ice cream recipe without additional treatment, and they perform identically to regular eggs in terms of flavor and texture.