What process applied to Matcha plants before harvest encourages the production of L-theanine and chlorophyll?

Answer

Shading the tea plants from direct sunlight for several weeks.

The characteristic brilliant green color and enhanced flavor profile of Matcha are achieved through a specific cultivation technique implemented before the leaves are picked. The plants intended for Matcha are subjected to deliberate shading, blocking them from direct sunlight for a period spanning several weeks. This environmental manipulation causes the plant to alter its chemical composition: it reduces the production of catechins, which are associated with bitterness, while simultaneously promoting higher levels of L-theanine, an amino acid contributing to sweetness and calm alertness, and boosting chlorophyll, which deepens the green hue.

What process applied to Matcha plants before harvest encourages the production of L-theanine and chlorophyll?
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