GUTsy Captain Zero Raspberry runs the fermentation until the bacteria have consumed all the cane sugar, then adds natural raspberry flavour and organic fruit extracts. Without sweetness to balance them, the flavours sit in different proportions to the standard version. On the nose the raspberry is fresh but noticeably sharper, with the more acidic fermented tea note sitting prominently beneath. On the palate the raspberry reads as tart rather than sweet, giving it an interesting sharpness. The berry and fermented tea combine into a clean, sour-fruit flavour profile. The finish is dry and brief. Some people find this more interesting than the sweetened version. The acidity is pronounced enough that it is worth knowing what you are in for before buying a case.