1. Quality: Flying caviar is produced in large quantities and is therefore relatively inexpensive. Sturgeon caviar is relatively more expensive due to lower production.
2. Taste: Flying caviar has smaller particles and a lighter taste, so it is often used as a sushi ingredient. Sturgeon caviar, on the other hand, has larger particles and a richer flavor, and is considered a premium ingredient, often used as a garnish or accompaniment to meals.
3. Color: Flying caviar is yellowish in color, while sturgeon caviar is grayish-black in color.
Overall, flying caviar is more quantitative, while sturgeon caviar is more qualitative. Which roe sauce you choose depends on your personal taste and budget.