Pengaruh Steam Blanching terhadap Aktivitas Polifenol Oksidase, Total Polifenol dan Aktivitas Antioksidan Biji Kakao

Penelitian ini bertujuan untuk untuk mengetahui pengaruh steam blanching terhadap aktivitas polifenol oksidase, total polifenol, dan aktivitas antioksidan biji kakao. Bii kakao segar yang telah dihilangkan pulpnya ditimbang sebanyak 100 dan 200 g kemudian masing masing massa biji kakao diberi perlakuan steam blanching selama 1, 3, dan 5 menit. Biji kakao steam blanching dianalisa karakteristik fisikokimia (kadar air, pH, warna dan suhu), gugus fungsional (FTIR), aktivitas polifenol oksidase (PPO), kandungan total polifenol, dan aktivitas antioksidan. Hasil penelitian menunjukkan bahwa steam blanching dengan perlakuan kombinasi antara massa 100 g dan lama 1 menit menyebabkan menurunnya aktivitas PPO dari 445,87 menjadi 11,28 U/g berat biji kakao segar (FW), meningkatkan kandungan total polifenol dari 72,63 menjadi 92,15 mg Ekuivalen Asam Galat (EAG)/g bubuk kakao bebas lemak (DS), dan meningkatkan aktivitas penangkapan radikal bebas DPPH dari 55,36 % menjadi 68,99 % atau dengan nilai IC50 dari 3,39 menjadi 2,58 ml/l apabila dibandingkan dengan kontrol (tanpa steam blanching). Aktivitas antioksidan pada biji kakao steam blanching juga lebih tinggi dibandingkan antioksidan sintetis seperti BHT dan asam askorbat. Kesimpulannya, steam blanching dapat menurunkan aktivitas PPO, meningkatan kandungan total polifenol dan meningkatkan aktivitas antioksidan. Oleh karena itu, perlakuan steam blanching dapat dijadikan sebagai salah satu alternatif proses pengolahan dalam mempertahankan antioksidan alami polifenol biji kakao.Steam blanching effect on polyphenol oxidase activity, total polyphenol content and antioxidant activity of cocoa beanThe aim of this research were to determine the effect of steam blanching on the activity of polyphenol oxidase, total polyphenol content, and antioxidant activity of cocoa beans. The fresh cocoa beans that have been removed the pulp were 100 and 200 g and then each cocoa beans mass was treated with steam blanching for 1, 3, and 5 minutes. Physicochemical characteristics (moisture content, pH, color, and temperature), functional group, polyphenol oxidase (PPO) activity, total polyphenol content and antioxidant activity of cocoa beans were observed. The results showed that steam blanching by treatment (100 g; 1 min) decreased of the PPO activity from 445.87 to 11.28 U/g of fresh weight (FW), increased total polyphenol content from 72.63 to 92.15 mg of Equivalent Galic Acid (EAG)/g defatted sample (DS), increased RSA DPPH from 55.36 % to 68.99 % or with IC50 value from 3.39 to 2.58 ml/l when compared to the control (without steam blanching). Antioxidant activity of steamed blanching cocoa beans also were detected higher than the synthetic antioxidants such as BHT and ascorbic acid. As conclusion, the steam blanching treatment might decrease the PPO activity, increase the total polyphenol content, and increase of antioxidant activity. Therefore, the steam blanching treatment could be used as an alternative process for preserving natural antioxidant of cocoa bean polyphenols.•