The use of borax as a food additive by some producers is intended to
preserve food longer so as to reduce production costs. Tofu is a soybeanproduct.
The high water content causes the tofu to spoil quickly and smells bad, at room
temperature tofu can only last 1-2 days. The use of borax in tofu soaking water can
make the texture of the tofu chewy and last up to 4- 5 days.
Based on Permenkes RI No. 1168 of 1999 concerning food chemical
additives, in food should not contain hazardous food additives, such as borax and
formalin. Taking borax can cause poisoning, brain, liver and kidney disorders, longterm use and in high doses can cause death. The purpose of this study was to
determine the presence or absence of borax content in tofu in the traditional
markets of Pati City, namely Pasar Puri, Pasar Kayen, Pasar Trangkil, Pasar
Rogowongso, Pasar Tayu and Pasar Gabus.
The results of the qualitative test used a flame test and tumeric paper,
namely six samples of tofu circulating in the Rogowongso market with traders with
sample codes I, II, III, IV, V, and VI positive for containing borax hazardous
substances. Then proceed with a quantitative test to determine the level of borax
contained in tofu, the results obtained from the tofu sample were 0.012%, 0.011%,
0.010%, 0.008, 0.016%, and 0.032%.
Keywords: Borax, UV-VIS spectrophotometry, tumeric paper