Pour 2/3 cup (150 ml) of the water into a glass and set aside. In a large pot, bring the remaining water, along with the purple corn, cinnamon stick, clove, and reserved apple skins to a boil.
Lower the heat to medium-low, and allow the mixture to gently simmer for one hour, until aromatic and the flavors have blended together.
Meanwhile, in a countertop blender, process the green apple, pineapple, lime juice, and ground cinnamon into a completely smooth purée. Transfer purée to another container and set aside.
In the same blender, blend the sugars, salt, stabilizer, and inulin (if using) with the reserved 150 ml of water on high until all the solids have completely dispersed. Set aside.
Once the chicha morada has finished stewing, remove from heat, and allow it to cool to warm. Strain half the chicha morada into the blender containing the sugars and stabilizers; blend once more.
Pour the mixture from the blender along with the rest of the chicha morada through a fine mesh strainer into the prepared ice bath to cool completely. Once cooled, whisk in the fruit purée.
Using a refractometer, measure the Brix of the base, verifying it is within the target range of 25 to 32 Brix. At this point, you can adjust the sweetness or tartness of the base with more sugar or lime –
adding just a teaspoon at a time and re-reading the brix after each addition.
Transfer the sorbet base to an airtight container and refrigerate for at least 12 hours and up to 2 days.
Churn the sorbetOnce the ice cream base is completely chilled, place a loaf pan in the freezer to chill. Immersion blend the base thoroughly before processing the ice cream base in an ice cream machine according to the manufacturer’s instructions.
Churn the sorbet until it reaches the texture of a stiff slushie (about 30°F or colder with a thermometer gun).
Transfer the sorbet to the chilled loaf pan. Press a piece of wax paper directly on top of the ice cream and freeze for at least 3 hours before serving.
Sorbet StabilizerMix 5 Tbsp. cellulose gum, 3 Tbsp. + 2 tsp. guar gum, 2 Tbsp. + 1 tsp. lambda carrageenan, 1 Tbsp. + 1/2 tsp. glucose powder together and store in an airtight container in a cool and dry place. Mix well before each use.
NOTEInulin* adds more body and a creamier mouthfeel to sorbets. If you prefer a sorbet with a cleaner and more refreshing meltdown, feel free to leave it out. Andean dried purple corn is sold as ears or loose kernels in many Latin supermarkets.
* Inulin is a powder made from chicory fiber, sold as a fiber supplement and prebiotic, widely available in health food stores and online. Incidentally, it’s also a useful tool for thickening watery sorbets. Be sure to use a flavorless inulin.