The Science of Freshness

To appreciate the importance of freshness, it's essential to understand what tea is from a botanical perspective. Green tea is made from the leaves of the Camellia sinensis plant. When these leaves are plucked and processed, they contain a myriad of compounds, including catechins, amino acids, and volatile oils. These compounds are responsible for the tea's flavor, aroma, and health benefits and Freshness in tea is largely determined by their preservation.

From the moment the tea leaves are plucked, they begin to undergo natural processes like oxidation and fermentation, which alter their chemical composition. In green tea, the aim is to minimize these processes to retain the tea's original flavor profile.

Factors Affecting Tea Freshness

Several key factors:

• Oxidation: Exposure to oxygen can lead to the breakdown of flavor and aroma compounds in green tea. This is why green tea undergoes minimal oxidation during processing compared to black or oolong teas.
• Moisture: Tea leaves are hygroscopic, meaning they absorb moisture from the air. Excess moisture can lead to mold growth and accelerate the degradation of the tea.
• Light: Ultraviolet light can degrade the compounds in tea leaves, particularly catechins, affecting both flavor and health benefits.
• Temperature: Higher temperatures can accelerate chemical reactions in the tea leaves, leading to faster degradation.

Production Process is Key

The journey of green tea begins with careful harvesting. The timing of the harvest is crucial; tea leaves plucked in early spring (known in Japan as "first flush") are often considered superior in quality due to their higher concentration of aromatic compounds. After harvesting, the tea leaves are quickly steamed or pan-fired, a process unique to green tea. This step is critical for freshness as it halts oxidation, allowing the leaves to retain their vibrant green color and fresh, grassy flavor.

A process that Mohei's ancestors has mastered and is continuously improving. 

Myths and Misconceptions about Freshness:

There are common misconceptions about what keeps tea fresh. For instance, refrigerating green tea is often suggested, but it can introduce moisture, which is detrimental. Another myth is that vacuum-sealed packaging extends the life of the tea indefinitely. While vacuum sealing can prolong freshness, it's not a panacea; the tea will still degrade over time, albeit more slowly.

The Role of Freshness in Health and Culture:

Freshness in green tea not only affects its flavor profile – the sweet, umami, and vegetal notes – but also its health benefits. Green tea is lauded for its high concentration of antioxidants, particularly epigallocatechin gallate (EGCG), which are best preserved in fresh tea. In Japanese tea culture, freshness is not just a product attribute; it's a philosophy. The Japanese tea ceremony places emphasis on the seasonality and freshness of tea, reflecting a deep appreciation for the transient beauty of nature.