Explain in detail of the material and methods of the processing of mix fruit jam from pineapple, orange, strawberry, and sugar.

To make a mixed fruit jam from pineapple, orange, strawberry, and sugar, you will need the following ingredients and equipment:

Ingredients:
- 2 cups diced pineapple
- 1 cup diced oranges
- 1 cup diced strawberries
- 3 cups sugar
- 1/4 cup lemon juice

Equipment:
- Large saucepan
- Wooden spoon
- Blender or food processor
- Sterilized glass jars with lids

Method:

1. Wash and dice the pineapple, oranges, and strawberries into small, uniform pieces.

2. In a large saucepan, combine the diced fruits with sugar and lemon juice. Stir well to mix all ingredients together.

3. Place the saucepan over medium heat and bring the fruit mixture to a boil. Stir constantly to ensure the sugar is completely dissolved.

4. Once the mixture reaches a rolling boil, reduce the heat to low and let it simmer for about 30-45 minutes. Stir occasionally to prevent sticking and burning.

5. As the fruit mixture simmers, use a blender or food processor to puree the mixture until smooth. Alternatively, you can leave some fruit chunks for texture if desired.

6. Continue to cook the mixture on low heat until it thickens to your desired consistency. This can take up to an hour, depending on how thick you want your jam to be.

7. Once the jam has thickened, remove it from the heat and let it cool slightly.

8. Pour the hot jam into sterilized glass jars, leaving some headspace at the top. Seal the jars tightly with lids.

9. Let the jars cool completely before storing them in the refrigerator. The jam will continue to thicken as it cools.

Your mixed fruit jam is now ready to enjoy on toast, pancakes, or as a topping for desserts. Store any leftover jam in the fridge for up to a month.