Influence of natural antioxidants and their carry-through property in biscuit processing

BACKGROUND: The present study has explored the use of natural antioxidants from plant sources such as hexane (G-1) and chloroform (G-2) extracts of Garcinia, Peltophorum ferrugineum flower extract (FE), turmeric powder (C-1) and curcumin (C-2), in biscuit preparation in the place of synthetic ones, and their carry-through properties were evaluated during processing and storage. Microstructure and electrophoretic characterization of biscuit dough were carried out to understand the influence of these natural antioxidants in the processing of biscuits. RESULTS: Biscuits prepared with C-1, C-2, G-1, and G-2 were well acceptable, and FE biscuits were least acceptable. Among the antioxidants used, C-2 was found to retain only 11.23% activity whereas G-2 had retained 51% activity after baking, which was comparable to synthetic antioxidant butylated hydroxyanisole (BHA) and better than tert-butylhydroquinone (TBHQ). Microstructure studies of biscuit dough indicated that in the case of G-1, G-2, C-1 and BHA the gluten network formation was intact when compared to FE and TBHQ. Supportive electrophoresis studies indicated that there was no change in the wheat protein subunits of different samples except for FE biscuit dough. CONCLUSION: Based on the result of retention of antioxidant activity during baking and storage, hexane and chloroform extracts of Garcinia (G-1, G-2) and turmeric powder (C-1) were found to be suitable for use in biscuits as natural antioxidants and results were comparable with BHA. The present study also indicated that protein subunits of biscuit dough were not affected by antioxidants. However, antioxidants influenced the protein-starch-lipid network during biscuit dough formation. (C) 2008 Society of Chemical Industry