Efficient tannase production using Brazilian citrus residues and potential application for orange juice valorization.

Tannase is an interesting enzyme due to its capacity to hydrolyze galotannins and polyphenol compounds. Tannase from Paecilomyces variotii has been produced from different residues, such as wheat, castor bean cake and pomegranate, and has shown great potential in Brazilian Citrus residue. The process of tannase production using solid-state fermentation was optimized and activity increased tenfold. The tannase produced showed optimum activity at pH 5.0, with 70 °C and 80% stability between pH 4.0–6.5 and 20–60 °C. The enzyme was then applied to orange juice by flavanone hydrolysis to increase antioxidant and functional activity. It was concluded that aglycon flavanones present higher functional activity than glycosylated flavanones. The results demonstrate the benefits of producing tannase (from a low-cost process) for the food industry. The enzyme reacts under a range of temperatures and pH levels, and increases the biological effects of orange juice. [ABSTRACT FROM AUTHOR]