The Science of Sweet Tea

thermometerOne of South’s unique tastes is for sweet tea. For those not acquainted with this beverage, sweet tea is like normal iced tea but with the addition of ludicrous amounts of sugar. The key to achieving this monumental level of sweetness is adding sugar to boiling hot tea before cooling. Heating water causes the molecules to move around faster creating greater space between them. Sugar molecules are able to quickly squeeze into these gaps allowing more sugar to quickly dissolve into the water.

Degrees Brix is the amount of sugar contained in an aqueous solution with one degree Brix being 1 gram of sucrose in 100 grams of solution. We can use this metric to figure out exactly how sweet, sweet tea can be.

By “sweet tea,” we mean “sweet.” As one food technologist told me, some of the sweetest glasses can hit 22 Brix of sugar. That means that 22 percent of the liquid consists of dissolved sugar solids, or, to put it in more meaningful terms: close to twice what you’d find in a can of Coke. 

However, this doesn’t always appear to be the case.  Take the sweet tea at McDonald’s.  It contains 59g of sugar in 32 fluid ounces (6.2 Brix).  While Coke is 85g in 32 fluid ounces is 9 Brix.  Indeed, the chart below of some favorite Southern spots to acquire the golden elixir suggest there is quite a bit of variability into how sweet, sweet tea can be.  And only in some locations top out over Coke.  If you make it home, chances are it is not as sweet as what you purchasing out.

Brand Brix
Homemade 2.4
Bojangles 3.8
McDonalds 6.2
Bob Evans 6.4
Churches Chicken 7.2
Coke 9.0
Sonic 9.5
Snapple 9.7
Hardees 10.2
Perkins 10.4
Lipton 10.5

Which turns us back to where exactly sweet tea is available. Internet group Eight over Five undertook an investigation into the relationship of sweet tea availability and the separation of Northern and Southern cultures in the United States. In the state of Virginia a distinctive line stretches across the state separating McDonald’s that serve sweet tea from those that do not. The shift in McDonald’s sweet tea service occurs in the southern part of Virginia. Interestingly, during the Civil War, the capital of the Union was Washington, DC and the Confederate capital was Richmond. These capitols are separated by less than 150 miles of Virginia countryside. It’s within this same area that the shift in sweet tea availability occurs as well, matching the Southerner’s preference for this sugary concoction.

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