Bloom gelatin fully in cold water before dissolving in warm puree to avoid lumps., Avoid adding hot gelatin directly to whipped cream or meringue; cool gelatin mixture to room temperature first., Use chilled bowls and cream for best whipping results., Egg whites must be free of yolk and whipped to stiff peaks for stable Italian meringue., Fold ingredients gently and progressively to preserve airiness in mousse., Strain raspberry puree through a fine sieve for smooth texture., Adjust sugar based on fruit sweetness to maintain balanced flavor., Moderate alcohol additions (e.g., raspberry liqueur) to avoid interfering with gelatin setting., Chill mousse several hours or overnight for best texture and stability., Store mousse covered in refrigerator up to two days; do not freeze when possible as texture may suffer.