A. The main difference between yellow and purple passion fruit lies in their appearance and taste. Yellow passion fruit has a bright yellow or golden outer skin when ripe, while purple passion fruit has a dark purple or maroon-coloured outer skin when ripe. Yellow passion fruit is generally larger than purple passion fruit and has a smoother skin texture. In terms of taste, yellow passion fruit is often described as having a more tart and tangy flavour, while purple passion fruit tends to be sweeter with a slightly floral and musky taste.