Answer

In Jainism, the not-good methods for making fruit juice are the ones that cause unnecessary himsa or involve impure/non-Jain ingredients.

Explanation

Generally, these methods are avoided:

• Over-grinding or excessive crushing of the fruit
• Heating or boiling the juice unnecessarily
• Fermenting the juice or keeping it for a long time until it spoils
• Using industrial clarification methods that involve animal-derived agents like gelatin or isinglass
• Using dirty or reused filters that are not clean and may create impurity

A Jain-friendly approach is:

• Use fresh fruit
• Prepare the juice simply and gently
• Strain it with a clean cloth or fine sieve if needed
• Drink it fresh, without unnecessary processing

Spiritual Understanding

Jain Dharma teaches ahimsa, purity, and restraint. So the best method is the one that causes the least harm and keeps the food simple and clean.

Takeaway

For Jain practice, avoid excessive processing, fermentation, and animal-based filtering aids. Choose the simplest and most compassionate method.