Question

The soft and fragile food products, having delicate flavors and colors, are best dried by which of the following method:

• A. Drum drying
• B. Vacuum drying
• C. Tray drying
• D. Freeze drying

Hint:

For questions about preserving the highest quality in a dried product (especially structure, flavor, color), the answer is almost always \textbf{Freeze Drying}. It is the premium, albeit most expensive, drying method.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The goal of drying is to remove water, but different methods use varying levels of heat and pressure, which can impact the quality of the final product. For delicate products, the gentlest method is required to preserve structure, flavor, and color.
Step 3: Detailed Explanation:
- Freeze drying (Lyophilization): This is the gentlest drying method. The product is first frozen, and then the water is removed by sublimation (turning directly from solid ice to vapor) under a high vacuum. Because the water is not in a liquid state and the process occurs at low temperatures, the food's structure is maintained, shrinkage is minimal, and heat-sensitive flavors and colors are exceptionally well-preserved. This is ideal for soft, fragile products like berries, coffee, and herbs.
- Drum drying and Tray drying use high heat, which can destroy delicate flavors, cause browning, and damage the structure of fragile foods.
- Vacuum drying is gentler than atmospheric drying because the vacuum lowers the boiling point of water, but it is not as gentle as freeze drying and can still lead to some structural collapse.
Step 4: Final Answer:
Freeze drying is the superior method for drying soft, fragile food products with delicate flavors and colors because it best preserves the original quality attributes. Therefore, option (D) is correct.