While there are some brands of bagged teas made with high quality whole tea leaves by a few tea merchants, the generic tea bag you find on the supermarket shelves is not representative of a truly great cup of tea. The primary difference between loose leaf tea and tea bags is the size of the leaves which has a direct effect on the quality of the resulting cup of tea.
Taste and Quality
Quality whole leaf tea is made from the top two leaves that are handpicked from each bush. Tea bags are generally filled with a much lower grade of tea, usually a grade called broken orange pekoe,* fannings (the tiniest pieces of broken leaves), and dust. Broken leaves infuse more quickly which is desirable in a tea bag. However, because of the larger surface area, broken leaves become stale very quickly and essential oils evaporate leaving a dull and tasteless tea.
Sustainability
Some tea manufacturers use paper tea bags that are not fully biodegradable. Tea bags are made with about 80% paper fiber but may also contain heat-resistant polypropylene that does not break down. And, companies that do use better grades of whole leaf tea packaged in delicate net or mesh bags are also a problem. While they theoretically allow more room for tea to brew, tea bags made from nylon mesh will not break down in the compost pile. While biodegradability of tea bags may not be high on manufacturers’ agendas, if sustainability is a concern of yours, choose loose leaf tea and throw the spent leaves in the garden.
Convenience
Without a doubt, at first glance tea bags definitely offer ease of use and convenience. But today, there are many options for brewing loose tea that are just as easy and convenient as a tea bag. We like the large strainer that fits inside a mug or teapot. Newer teapots come with a strainer basket. Simply measure loose tea into the basket, add water, and remove strainer it before serving.
Cost
Have you ever checked the weight on a box of premium tea bags? Sometimes people simply notice the number of tea bags inside the box without giving much consideration for the weight. Take a moment to calculate the number of bags in the box and the weight. If you enjoy a ‘mug’ of tea, you’ll need to use two tea bags (or possibly three!) to achieve optimal flavor (which gets pricey) or be content with insipid flavor using one tea bag. One ounce of loose tea will make a generous 12-15 cups of tea. If you really, really appreciate having a quality cup of tea and good value, choose loose leaf tea.
Flavor
Whole leaf tea contains essential oils that are responsible for the delightful flavor of tea. Besides the leaf size, there is also the space factor when infusing the leaves. Whole tea leaves need space to swell, expand, and unfurl when brewing. Good water circulation around the leaves is important, which doesn't happen in a cramped little tea bag or small tea ball or infuser. Allowing water to circulate around the leaves freely also helps to extract beneficial antioxidants and flavonoids.
Variety
While there are many bagged varieties to choose from on the supermarket shelf, consider the almost endless variety of loose leaf tea available. If you desire a change, try blending two of your favorite teas. And don’t forget to store tea properly — keep it in a tin with a tight fitting lid, or place in a jar with a lid in a dark cupboard. It’s helpful to mark the date of purchase on the tin or jar. Use within a year of purchase and toss any tea you’ve been 'saving' that is over a year old. Remember: Life's too short to drink bad tea!
*Since much of the bagged tea sold in the US is marked ‘orange pekoe’ many people think that orange pekoe is a special kind of tea. It is not a kind of tea, but rather a grading measurement that applies only to the size and physical condition of the leaves, not their kind or quality. Most tea that is labeled orange pekoe is blended black tea, typically from India or Sri Lanka. It's an acceptable grade, but not a great grade.