Sun tea, or not sun tea?

Summer and iced tea were made for one another. Each needs the other in order to provide maximum enjoyment to the person lucky enough to reside at the intersection of cold drink and hot air. Iced tea makes summer better. And without summer, iced tea could not possibly be as good.

Iced tea is not the only cold beverage on the planet, but the high content of plant material sets it apart. The leaves, flowers, stems, roots and seeds used in tea add myriad flavors, colors, medicinal qualities, and other properties. While usually made from purchased, pre-processed plant parts, tea can be made from gathered plants as well, like nettles or wintergreen, in either fresh or dried form. Basically, any plant part that spends time in water will yield some sort of tea. Add ice to it, and sweetener, and you’re good to go.

Sun tea, in many ways, is the poster child for summer time iced beverage. The way it’s made, by steeping the tea materials in a jar of sundrenched water, is about as elegant and poetic as food preparation can get. As the afternoon wears on, sun rays pierce the darkening liquid and light up the warm glass jar like a lamp, and it’s easy to see the romance in this iconic, solar-powered summer beverage.

With that being said, the argument for making sun tea, compared to using other tea preparation techniques, is not watertight. Aside from the spectacle, the tangible benefits of sun tea are questionable. And depending on the circumstances and materials involved, sun tea could actually be uniquely dangerous.

If either the plant materials or your kitchen gear are contaminated with dangerous bacteria, the warm conditions inside that sunny jar will be favorable to their proliferation. This reality has compelled many purveyors of sun tea recipes to warn about the possibility of sun tea-borne food poisoning, and recommend tactics like sterilizing the vessel, making just enough tea for immediate consumption, and not letting it steep for more than a few hours. It’s usually advised to discard the sun tea at any hint of problem, such as an off-smell, or if it develops a thick, syrupy viscosity.

The risk is small, but statistics would be of little comfort to a victim of food poisoning. Sun tea diehards, you’ve been warned.

There’s no reason, meanwhile, why tea can’t be made in cold water, in the fridge, in the dark (assuming the fridge light turns off when you close the door). It’s safer than sun tea, and while the steeping doesn’t happen as fast, it’s summertime, so what’s the hurry? And if there is a rush order for iced tea, using boiling water isn’t the end of the world either.

Harold McGee, writing for The New York Times, lays down the basics behind the choice between hot and cold brewing of tea, and coffee as well.

Hot water, he explains, extracts the plant components more rapidly, and extracts more of them, but also cooks as it extracts. In doing so, many of these substances are chemically changed. “Cold water, in contrast, extracts more slowly and selectively, produces a simpler extract, and doesn’t change the original flavor substances as much.”

According to McGee, hot water makes the quickest batch of tea, while cold water makes the best. Sun tea, we can interpolate, exists somewhere in the middle, in terms of both speed and quality.

I visited my local herb store in hopes of finding some tea-making materials, and hopefully some insight into the significance of various water temperatures in tea making. When the cashier saw my hibiscus leaves, she mentioned that she loves using them for sun tea.

I asked her about the possible health risks of sun tea. “Yeah, it’s kind of a scary setup,” she admitted. “Warm water, in an airtight container, with plant matter and maybe sugar,” she elaborated. “I wouldn’t do it with raw plant matter.” But if the herbs were professionally dried the risk is low, she said. “And be sure to sterilize the jar and all of the utensils,” she added.

But why risk it, I asked, when quality tea can be made safely in cool water?

“I believe in the energy of the sun, and what it does to the tea,” she said.

I brought home some black tea with rosehips, along with my hibiscus flowers. I subjected each type of tea to three preparation techniques: boiling water, cold water, and the energy of the sun. What I found left me thoroughly confused.

The hibiscus steeped in cold water was the strongest, and that made in boiling water was the weakest. The sun-brewed hibiscus, predictably, was in the middle.

The black tea with rosehips performed the same way. The cold-brewed batch, while lighter in color than the boiled water batch, had a stronger flavor. And that dangerous sun tea, as expected, was in the middle in terms of intensity, though I detected a softer, fuller flavor.

Given the diversity of materials with which tea is made, I suppose it’s to be expected that different plant parts will react differently to various water temperatures. But before we go splitting hairs among tea prep methods, it’s worth noting that all three preparations of both types of tea tasted fine, if different, and none made me sick.

Hibiscus leaf tea has a penetrating fragrance that is astoundingly refreshing. A Mexican iced tea of hibiscus leaves, called Jamaica (Ha-My-Ka), can be made by filtering the leaves, diluting the tea to a pleasant strength, sweetening with sugar or honey, and adding ice cubes. Do the same, and your summer will be complete. You may or may not be drinking sun tea, but you should most definitely be drinking it in the sun.