Before the freezing happens, an ice cream base often needs to be cooked. This cooking process denatures dairy proteins, which then capture free-roaming water in the base, resulting in smoother and less icy ice cream. Precise temperature control is important when cooking the base, especially with custard-based ice creams that include egg yolks. If the heat is too high, there is the risk of curdling the yolks. With sous vide, we eliminated potential problems and simplified the process. We just combined the ingredients and circulated them for an hour. We further combated iciness by incorporating nonfat milk powder and corn syrup, which help by trapping water in the base, thus preventing the formation of large ice crystals. The base is “cured” overnight in the refrigerator to give the dairy proteins more opportunities to capture water.
Notes
- A vanilla bean gives the ice cream the deepest flavor, but 2 teaspoons vanilla extract can be substituted.
- Be sure to double bag ice cream base to protect against seam failure.
- If using a canister-style ice cream maker, be sure to freeze the empty canister for at least 24 hours and preferably 48 hours before churning. For self-refrigerating ice cream makers, prechill the canister by running the machine for 10 minutes before pouring in the custard.
- To Make Ahead Ice cream can be frozen for up to 2 weeks.
Ingredients
- 1 vanilla bean
- 1½ cups whole milk
- 1½ cups heavy cream
- ¾ cup nonfat dry milk powder
- ½ cup sugar
- ¼ cup light corn syrup
- 6 large egg yolk
- ¼ teaspoon salt
Instructions
- Using sous vide circulator, bring water to 180°F/82°C in 7-quart container.
Prepare the ice cream base:
- Cut vanilla bean in half lengthwise. Using tip of paring knife, scrape out seeds.
- Whisk vanilla bean and seeds, milk, cream, milk powder, sugar, corn syrup, egg yolks, and salt in large bowl until sugar has dissolved.
Cook the base:
- Transfer the mixture to a 1-gallon zipper-lock freezer bag. Seal bag, pressing out as much air as possible.
- Place bag in second 1-gallon freezer bag and seal.
- Gently lower bag into prepared water bath until ice cream base is fully submerged, and then clip top corner of bag to side of water bath container, allowing remaining air bubbles to rise to top of bag.
- Reopen 1 corner of zipper, release remaining air bubbles, and reseal bag.
- Cover and cook for at least 1 hour or up to 1½ hours.
Chill the mixture:
- Fill a large bowl halfway with ice and water.
- Transfer zipper-lock bag to ice bath and let sit until chilled, about 30 minutes.
- Strain custard through fine-mesh strainer into airtight container; discard solids.
- Refrigerate for at least 12 hours or up to 24 hours.
Churn the ice cream and freeze:
- Churn custard in ice cream maker until mixture resembles thick soft serve ice cream and registers 21°F/–6°C.
- Transfer to clean airtight container and freeze until hard, at least 2 hours, before serving.