Cold brewed beverages have become hot this year, and everyone is trying to capture this segment of the business. With the success of #coldbrewcoffee, other industries are trying to capitalize on this trend, and tea is no exception.
Cold brew, also referred to as cold water extraction, was initially developed to brew ground coffee in cool water for an extended period, typically 12+ hours. Room temperature or cold water would slowly leach the flavor from the ground coffee beans producing a radically different profile than coffee produced with the traditional hot water brew method.
Brewing at lower temperatures resulted in less acidity and caffeine, since high temperatures are needed to fully extract the natural caffeine, oils and fatty acids found in coffee. Cold brew coffee is about 70% less acidic than that of traditional hot brewed coffee.
This lower acidity produces a smoother cup of coffee, which is slightly sweeter, that is not as harsh on the stomach. Even though the caffeine is lower with this type of extraction, the coffee to water ratio is higher and the brew time is longer; therefore cold brew typically has a higher amount of caffeine per serving.
Cold brew coffee ...produces a smoother cup of coffee, which is slightly sweeter, that is not as harsh on the stomach...typically has a higher amount of caffeine per serving.
With the success of cold brew coffee, tea was the natural successor everyone turned to as the next “big thing.” Cold brew tea has become just as craveable.
However, the preparation of coffee and tea are not the same. The biggest concern with tea has to do with the microbiological levels naturally found in tea leaves. Coffee beans are high-temperature roasted, which kills microbiological organisms that are typically found on the green coffee bean. With tea leaves, the typical kill-step is the steeping process of the leaves in hot water. Not having a kill step could lead to food safety issues.
Cold brew tea can be just as antioxidant rich as traditionally steeped tea. According to Professor Jeng-Leun Mau of the National Chung Hsing University, Taiwan: cold brew tea steeped for 12 hours had antioxidant levels equal to or greater than tea steeped in hot water for 5 minutes. The study cautions shifting results depending on several variables, such as the type of tea used. Additionally, the study states that the caffeine content of the cold brew tea was one half to two-thirds that of hot steeped tea.
It is important to note that not all teas will taste delicious when prepared as cold brew. Consumers should experiment to find the right tea, length of extraction time, leaf grade, and tea to water ratio. Additionally, testing in smaller batches and then extrapolating to larger batches does not always work. This has to do mainly with the depth of the tea and the lack of agitation of the leaves. Below is a guide to help you pick the best teas to try for your #coldbrewtea:
White teas works well in cold brew and should be steeped for 12 hours.
Green teas, especially those that are steamed green teas like Japanese green teas, are perfect for cold brew and are ready in a few hours.
Matcha Green teas can be used as well for an instant cold brew delight.
Oolong teas of any type are an excellent choice, as the amount of tea needed per batch tends to be less and should be steeped for 12 hours.
Black teas, depending on origin, can work but should be prepared using the hot water step first.
Pu-erh teas are not recommend due to the processing of the leaf as these teas have a greater risk of food safety issues being prepared via cold brew method.
Herbals/tisanes should only be used if purchased from a reputable source and success varies based on botanical used. Prepare using the hot water step first is critical.
The Risky Business
To mitigate risk, consumers should only use teas from reputable sources that can provide Certificates of Analysis on their teas or have third party verified lab analysis for microbiological levels. The highest potential risk comes from e-coli and salmonella, though excessively high counts of molds and yeast could also lead to potential food safety issues. Organic teas are not the answer to this potential issue as microbiological levels are virtually the same on conventional and organic tea leaves. The major difference between conventional and organic tea leaves are the pesticide residuals and the types of pesticides used.
Additionally, herbal teas or tisanes are of greater concern as these have a much greater risk of higher microbiological levels. Good Manufacturing Practices (GMPs) and Sanitation Standard Operating Procedures (SSOPs) should be followed when preparing cold brew beverages as there is greater potential of microbiological contamination from the environment, the equipment used, and of that of the preparer.
Consumers could also be concerned about presence of staphylococcus aureus, botulism, and listeria. Just like with hot prepared beverages, filtered clean water is always essential.
The Danger Zone for food is between 40• -140• F. To help mitigate food safety issues with cold brew tea, most tea companies’ employee one of the two measures:
Prepare the cold brew tea with water below 40• F and store the tea in the refrigerator during the entire brew process; and store the finished beverage in the refrigerator.
First add 200•+ F water covering the tea leaves for 1-1.5 minutes. Then add cold water and refrigerate as noted above.
We Can Help
If you're looking to create Cold Brew Tea for your Café or Tea Shop and would like assistance tweaking the perfect recipe, we'd be glad to assist you. Whether it's a just a few pointers or complete custom program, we're happy to help! Drop an email to Scott@HulaConsulting.com to get started.