Kajian awal pemanfaatan pektin dan zat warna alami dari kulit buah naga menggunakan pelarut asam asetat pada pembuatan jeli

Abstract

Dragon fruit (hylocereus undatus) is a fruit that quite liked by Indonesian people, can grow well in tropic climate. Dragon fruit production in 2014 are up to 55 ton/ha. This research use dragon fruit peel because the peel has not been used well, considering the high level of pectiine and natural color substance. The making of jelly also affected by pH, sugar, and heating time. Food product processing is done by using extraction method, followed by gelatination. The principle of extraction is solut mass transfer from solid to solvent. Product obtained from extraction process is pectine and dragon fruit’s peel natural color substance. Pectine and color substance are extracted using batch extractor in 1L extractor. Extracted using 30 minutes with F/S = 1/10. Temperature variance are 47,90 – 97,10, the accidity are 0,0144 – 0,52 with five replication. The observed response in jelly are viscocitas extract, color, and gel’s strength. Tool used to observe gel’s strength is analyzer texture. Jelly is made by extracting dry dragon’s fruit peel with water level of 9,32%-b using acetat acid solvent with dispersion contact with sugar. The result of analysis using central composite design experiment with five centre point. The research result of gel’s strength has the range of 9,819 – 16,155 gr, no less strong than jelly that sold in the market. Optimum condition of making jelly using acetat acid solvent gained in extraction temperature of 50,000C and pH of 3,3.