Cold brewing leaves tea in lower-temperature water for an extended period, which can yield a gentler profile than hot brewing; however, it is not simply a matter of switching the hot-water step to "cold". Steeping time, container hygiene, and refrigeration management must all be organised together.
At home, start with a modest measure of tea, using a clean, sealable, food-grade container and safe drinking water, then place it into the refrigerator. For your first trial, record the leaf dose, water volume, start time, and time of serving; if the flavour is too mild, adjust either the time or the leaf quantity. Begin with small batches to avoid producing large quantities of surplus overnight beverage just to test a single flavour.
Outlets must treat cold brewing as a production protocol
Food service settings require internal procedures covering container washing, refrigeration temperatures, batch labelling, and shelf life, with exact practices determined by local food safety regulations. Dry tea leaves cannot be assumed to yield a brewed beverage that remains stable at room temperature for long periods. If adding fruit, sugar, or milk, shelf life and allergen considerations also change.
Both green tea and oolong tea can be used for flavour development, but how different leaves perform in cold brewing must be evaluated through actual recipes. Product data for Jiang Rong Hao teas can provide a starting point for selection, but cold-brew shelf life and safety parameters should not be deduced from product titles.
If selling cold-brewed drinks, the production batch, initial refrigeration time, and discard time should all be traceable; domestic preparation cannot serve directly as an operational standard for food service premises.