Why is temperature control important during matcha processing?

The Importance of Temperature Control in Matcha Processing

Temperature control is crucial in matcha processing as it directly impacts the product's color, flavor, nutritional value, safety, and overall quality. Key reasons include:

Preventing Oxidation and Preserving Color: Matcha's vibrant green color comes from chlorophyll. Excessively high temperatures (e.g., exceeding 100°C during steaming) degrade chlorophyll, causing yellowing or browning. Insufficient temperatures (e.g., below 90°C) fail to fully inactivate polyphenol oxidase, triggering oxidation and loss of freshness.
Retaining Flavor and Aroma: Matcha's unique flavor profile (e.g., umami and freshness) relies on volatile compounds and amino acids (like theanine). High temperatures destroy these compounds, creating burnt bitterness. Low temperatures inadequately suppress enzymatic activity, resulting in flat or unstable flavors.
Protecting Nutritional Components: Matcha is rich in antioxidants (e.g., catechins), vitamins, and amino acids. Temperature control (e.g., maintaining 50-100°C during steaming and drying) minimizes degradation of heat-sensitive compounds, ensuring maximum nutritional value.
Ensuring Safety and Drying Effectiveness: During drying, excessive heat (e.g., over 70°C) can cause scorching, affecting taste. Insufficient heat (e.g., below 40°C) leads to inadequate drying, increasing moisture content and the risk of microbial contamination (e.g., mold).
Optimizing the Grinding Process: Friction during grinding into powder can raise temperatures (above 40°C), causing oxidation or flavor changes. Temperature control (e.g., using cooling systems) produces fine, uniform powder, enhancing texture and solubility.

In summary, precise temperature control is central to achieving high-quality matcha, ensuring product consistency, safety, and consumer satisfaction.