1Place apples and water in a large saucepan. Bring to a boil, reduce heat, and cook 25 minutes, or until apples are tender, stirring occasionally. Add more water as necessary to keep the apples simmering.
2Wrap mustard seed in cheesecloth, and place with apples. Mix tomatoes, onions, garlic, sultanas, sugar, curry powder, cayenne pepper, salt and vinegar into saucepan. Stir until sugar has dissolved.
3Bring the mixture to a boil. Reduce heat, and simmer 3 hours, stirring occassionally, until a thick chutney remains. Remove and discard wrapped mustard seed. Seal chutney in sterile containers until serving.