Regenerative efficacy of tert-butyl hydroquinone (TBHQ) on dehydrogenated ascorbic acid and its corresponding application to liqueur chocolate

Abstract In this study, a polyethylene (PE) film contained tert-butyl hydroquinone (TBHQ) was immersed into an aqueous solution containing dehydrogenated ascorbic acid (DHA) as a separable system for verifying the regenerative effect between the two antioxidants with different solubilities. It was confirmed that DHA was regenerated to either ascorbic acid (AA) with the presence of TBHQ; and the regeneration rate of AA was significantly increased compared with the control without using the TBHQ-contained PE film. The extent of regeneration from DHA to AA was influenced by the following factors, including surface area of PE film, content of TBHQ, reaction time, and temperature. The regenerative mechanism of DHA to AA by TBHQ was proposed accordingly in which DHA was regenerated to AA by TBHQ, and the TBHQ was reacted to 2-tert-butyl-1,4-benzoquinone (TQ) as one of the oxidation products. A further application of the two antioxidants to liqueur chocolate was adopted. Results showed that the TBHQ added into chocolate shell significantly improved the antioxidant capacity of AA when added into the liquor filling. Therefore, such an established antioxidant combination would expect to extend the shelf-life of liqueur chocolate.