Tofu A without formaldehyde, Tofu B without formalin, Tofu C with formalin September 30, 2017 (September 30, 2017) Reyshan Tofu A without formaldehyde, Tofu B without formalin, Tofu C with formalin Tissue paper that has been soaked with dragon fruit skin extract Tissue paper that has been silenced for 10 minutes Return to: Utilization of Red Dragon Fruit Skin (Hylocereus Costaricensis) as an Indicator of Formalin and Borax in Food