Tang
A powdered, orange-flavored, vitamin-C-fortified drink mix meant to be stirred into water; in cooking it works as a shelf-stable shortcut for concentrated orange flavor plus sugar and citric acid, not as a beverage on its own.
Buying guidance
Check whether the container is the classic sweetened mix or an unsweetened/sugar-free version -- they behave very differently in a dish, since the unsweetened kind needs added sugar to match. A packet sized for a full pitcher is far more concentrated than a teaspoon-scale seasoning use, so measure by whatever amount a dish calls for, not the drink-mix directions on the container.
Substitutions
- Orange zest plus a little sugar -- fresher, more natural flavor without the powdery aftertaste, though it won't dissolve into a dry mix the way Tang does.
- Another powdered orange drink mix -- close enough in most uses; check its sugar content against Tang's before matching quantities.
Tips & common mistakes
Stirring it into a liquid too quickly, or adding it straight to something hot without dissolving it first, can leave gritty, intensely sour pockets of undissolved powder -- dissolve it in a small amount of liquid before combining it with the rest.
Storage
Keep the container tightly sealed between uses -- the powder pulls in ambient moisture and clumps into hard lumps within an open canister, especially in a humid kitchen, and a clumped batch is unusable even though the flavor itself isn't affected.