Characteristics of sponge cake preserved by green tea extract powder

The green tea leaves were extracted and spray-dried to make powder. The polyphenol in green tea is known for its antioxidant and antimicrobial activities. This study investigated the application of green tea extraction powder as a preservative in sponge cake. Our green tea extract powder contained a total polyphenol content of 322.6 mg GAE/g and EGCG content of 11.4%. Green tea extract powder was added to sponge cakes at concentrations of 0.5, 1.0, 1.5, and 2.0% (w/w wheat flour mass). The sponge cakes were tested for some properties including total polyphenol content, antioxidant activity, peroxide value, sensory acceptance, and microbial quantity. As a result, the sponge cake with 1.0% green tea extract powder obtained the best quality with low peroxide value and good microbial quality. Also, the addition of green tea extract powder kept good-quality sponge cakes for 14 days when they were stored at room temperature in sealed packaging. Practical applications Green tea extract powder rich in polyphenols had not only high antioxidant activity but also microbial inhibitory properties. Therefore, green tea extract powder could function as a natural and healthy additive, replacing chemical synthetic additives to preserve fresh sponge cakes.