TBHQ or tertiary butylhydroquinone is an anti-oxidant. It is used as a food additive and as a preservative. Its E number is E319.
It is available in 500gm and 25kg packing.
130- 131, Radha Bazar Street, Behind Lal Bazar Head Quarters, Near HDFC Bank, Kolkata, West Bengal, 700001, India