KARAKTERISTIK FISIKOKIMIA ANTOSIANIN EKSTRAK KULIT BUAH NAGA MERAH MENGGUNAKAN METODE UAE (Physicochemical Characteristics of Red Dragon Fruit Skin Anthocyanin Extracts using UAE Method)

Dragon fruit peel (Hylocereus polyrhizus) contains anthocyanin which can be used as a potential natural colorant. Anthocyanins can be taken through the extraction process. The extraction of anthocyanin was performed by UAE (Ultrasound Assisted Extraction) method. UAE was chosen because it can result greater extraction efficiency and shorter operating times compared to conventional method. This study aims was to determine the effects of different amplitude  and extraction times on the characteristics of dragron fruit peels extract using UAE. The control used was maceration method. The operating amplitude were evaluated at two levels  65% and 95%. Ultrasonic processor of 500 W output with frequency 20 kHz, solid-solvent ratio 1: 20,  60 mesh particle size with 15 minutes, 30 minutes and 45 minutes extraction times. The solvent used was aquadest with citric acid 10%. The method used was laboratory experiments using descriptive analysis. Characteristics of dragron fruit peel extracts investigated were total yield, residual solvent content, specific gravity, total anthocyanin, pH, and colour characteristics. The results showed that the dragon fruit peel extracts with amplitude 65% and extraction time of 45 minutes was the best treatment with total yield 10.62%, residual solvent content 37.50%, spesific gravity 1.2198, total anthocyanin content 29.640 ppm, pH 2.80,   respectively. Based on hue angle (23.42o) the dragon fruit peel extracts obtained was resulting in red colour. Meanwhile, control treatment revealed that total yield was 9.44%,  residual solvent content was 52.67%, spesific gravity 1.0609, total anthocyanin content  24.074 ppm, pH 3.06, and hue angle 33.16 o. It proven that UAE could increase the effectiveness of anthocyanin extraction and reduce residual solvent content  of dragon fruit peel extracts compared to maceration.  Hence, the present study makes influences of ultrasound technique on physico-chemical characteristics during extraction.  Red dragon fruit skin (Hylocereus polyrhizus) contains naturally pigment as anthocyanin. Anthocyanins can be extracted using conventionally or other method. Ultrasound Assisted Extraction (UAE) is a prospective extraction method because resulting higher yield and shorten time process. The aim of this study was to identify the effect of extraction time and amplitude to the physicochemical characteristic of extract red dragon fruit’s skin. The maceration method was used as control treatment. The parameters observed were total extraction yield, residual solvent content, anthocyanin content, pH, specific gravity and colour. The method used was laboratory experiment by using descriptive analysis. The research showed extraction time at 45 minutes and amplitude number 65% was a best variables extraction which resulted total yield 10.62%, residual solvent content 37.50%, specific gravity 1.2198, total anthocyanin content 29.640 ppm, pH 2.80, respectively. Based on hue angle (23.42o) indicated that the dragon fruit peel extract was red colour. Meanwhile, control treatment resulted a total yield was 9.44%, residual solvent content was 52.67%, specific gravity 1.0609, total anthocyanin content 24.074 ppm, pH 3.06, and hue angle 33.16o. The UAE method revealed a better extraction method than maceration to produce a higher red dragon fruit’s skin extracts and anthocyanin concentration. Keywords: anthocyanin, extract, physicochemical characteristic, red dragon fruit skin, UAE   ABSTRAKKulit buah naga merah (Hylocereus polyrhizus) mengandung pigmen alami sebagai antosianin. Antosianin dapat diekstraksi dengan cara konvensional atau metode lainnya.  Ultrasound Assisted Extraction (UAE) merupakan metode ekstraksi prospektif karena menghasilkan rendemen lebih tinggi dan waktu proses lebih singkat. Penelitian ini bertujuan untuk mengkaji lama waktu ekstraksi dan amplitudo terhadap karakteristik fisikokimia ekstrak kulit buah naga merah. Metode maserasi dilakukan sebagai kontrol. Karakteristik ekstrak yang diamati meliputi rendemen, kadar sisa pelarut, total antosianin, pH, bobot jenis dan warna. Metode penelitian yang digunakan adalah penelitian eksperimental laboratorium dengan analisis deskriptif. Hasil penelitian menunjukkan bahwa kulit buah naga merah dengan amplitudo 65% dan lama ekstraksi 45 menit merupakan perlakuan terbaik dengan rendemen total 10,62%, kadar sisa pelarut 37,50%, bobot jenis 1,2198, kadar total antosianin sebesar 29,640 ppm, pH 2,80. Berdasarkan nilai hue (23,42o) ekstrak tersebut berwarna merah. Sedangkan perlakuan kontrol menghasilkan rendemen total 9,44%, kadar sisa pelarut 52,67%, bobot jenis 1,0609, kadar total antosianin sebesar 24,074 ppm, pH 3,06 dan hue 33,16o. Pada penelitian ini dibuktikan bahwa metode UAE menghasilkan lebih banyak ekstrak kulit buah naga merah dan konsentrasi antosianin lebih tinggi dibandingkan metode maserasi. Kata kunci: antosianin, ekstrak, karakteristik fisikokimia, kulit buah naga merah, UA