Having the Right Information is Key:
What most people aren't aware of is that experts grade matcha according to color, aroma, flavor, texture, and freshness. Also, authentic matcha is produced only in Japan, using strict harvesting methods developed over a 1,000 year old growing tradition.
These grades range from the highest quality (most expensive) to lowest (least expensive). The brighter the color, the richer the aroma, the deeper the flavor, the finer the powder, and the fresher the product, the higher the grade and the higher the price. Few people can afford to use the top grades of matcha as an everyday beverage, but many of the less pricey midgrades are excellent.
In Japan, the highest grades of matcha are often sold as “thick tea” (koicha), because they are suitable for the unusual preparation made with a much greater ratio of matcha powder to water than the familiar “thin tea” (usucha). Thick tea has the consistency of heavy syrup; it is sipped from a communal bowl by guests at the end of a formal tea ceremony. All thick teas can be used to prepare thin tea if you can afford them, but thin teas are not considered good enough to make thick tea. Forget thick tea. If you have a chance to experience a tea ceremony in Japan, it will be an informal one, where the only form of matcha served is thin tea.
Most of us are going to enjoy matcha as thin tea, hot or cold. And most of us will want to use the better grades of thin tea. Call them “premium” if you want, but drop the term “ceremonial grade.” There is no such thing in Japan. Any high-quality matcha is appropriate for use in the tea ceremony, but the vast majority of Japanese matcha drinkers consume it as we do, not as part of any ceremony. They buy the best quality tea they can afford. “Ceremonial grade” seems to be an American invention. Too often it is used as a marketing catch-phrase to sell less-than-high-grade matcha.
Lower quality matcha is sometimes called “food” or “culinary” grade, because it works well as an ingredient in green tea ice cream and other sweet and savory dishes but is likely to be disappointing as tea. Lower quality matcha is not as vibrant green, aromatic, richly flavored, and fine textured as the better stuff, and, of course, it is less expensive.
The Bottom Line
Matcha is graded from highest quality to lowest quality based on color, aroma, flavor, texture, and freshness – and priced accordingly.
Any high-quality matcha might be called “ceremonial grade,” and any low-quality matcha might be called “culinary grade,” but, really, those terms are meaningless.
You can buy cheaper matcha to use in food preparation, as long as you like its flavor. However, if you're looking to enjoy matcha as a daily beverage, get the highest quality you can afford.
P.S. A rule of thumb is start with a Sipping Matcha (i.e. Thin Tea) as you learn the technique and preparation. Or, as your interest demands the absolute highest quality, choose a Thick Tea.