
Yellow bell pepper is a sweet, non-pungent variety of Capsicum annuum with zero heat on the Scoville scale.
Nothing reproduces its fresh capsicum aroma when it is the main feature. For a minor color or sweetness role, another mild yellow vegetable such as yellow tomato will do, with syrup added half a barspoon at a time to balance.
Chili pepper
Yellow ones exist and they carry capsaicin; a bell pepper carries none at all. Swapping one in turns a mild savory drink into a hot one.
Red and orange bell peppers
Further ripening makes them sweeter and their color stronger, and they swap in directly; the drink simply comes out redder and a shade sweeter.
A whole pepper keeps a week or more in the fridge and softens from the stem end. Cut, it goes limp within a day or two. Pressed juice will not keep to the next service, so it is made to order.