How do you ripen custard apples?

1. Select: Choose firm but slightly soft custard apples with a slight yellowish or brownish color. Avoid those that are too hard or have dark spots.

2. Paper Bag Method: Place the custard apples in a paper bag with a ripe banana or apple (ethylene-producing fruits). The ethylene gas emitted by these fruits will help speed up the ripening process.

3. Temperature: Keep the bag in a warm place but not in direct sunlight. The ideal temperature for ripening custard apples is around 70-80°F (21-27°C).

4. Check Regularly: Check the custard apples daily. They usually ripen within 2-5 days, depending on their initial ripeness.

5. Gently Squeeze: Gently squeeze the custard apples to check their ripeness. Ripe custard apples will give a slight to moderate pressure when squeezed.

6. Color Change: As they ripen, the custard apples will turn a deeper shade of yellow or brown. The skin may also develop slight wrinkles.

7. Smell Test: Ripe custard apples have a sweet, fragrant aroma. Sniff the fruit to gauge its ripeness.

8. Ready to Eat: Once the custard apples are fully ripe, they will have a smooth, custard-like texture and be sweet and juicy.

Remember, the ripening process may vary depending on the variety and freshness of the custard apples. Be patient, and they'll be ready to enjoy in no time.