Karakteristik Mutu dan Organoleptik Permen Jelly Kulit Buah Naga Merah (Hylocereus polyrhizus) dengan Penambahan Ekstrak Ubi Jalar Ungu dan Konsentrasi Karagenan

Abstract

Red dragon fruit peel has higher antioxidant activity than its flesh, making it a potential ingredient for jelly candy. This study was aimed to evaluate the effects of adding purple sweet potato extract and different carrageenan concentrations, as well as their interaction, on the quality and organoleptic characteristics of jelly candy made from red dragon fruit peel. A factorial Completely Randomized Design (CRD) was used with two factors: purple sweet potato extract (U): (5%; 10%; 15%; and 20%) and carrageenan concentration (K): (2.5%; 3%; 3.5%; and 4%). Parameters analyzed included moisture content, ash content, antioxidant activity (IC50), color index, reducing sugar, texture properties (hardness, cohesiveness, springiness, gumminess, chewiness), total soluble solids, pH, and sensory attributes (color, aroma, taste, texture, and overall acceptance). The results showed that the addition of purple sweet potato extract had a significant effect (P<0.01) on antioxidant activity, color index, reducing sugar, texture properties, total soluble solids, and sensory evaluation of color, texture, and overall acceptance. Carrageenan concentration had highly significant affect on (P<0.01) moisture content, ash content, antioxidant activity, color index, reducing sugar, texture properties, total soluble solids, pH, and most sensory attributes, and had a significant effect (P<0.05) on texture preference. The interaction of both factors had highly significant affect (P<0.01) on antioxidant activity, color index (ºHue), reducing sugar, total soluble solids, and gumminess, and significantly affected (P<0.05) hardness. The best treatment based on the De Garmo method was U4K1, with the addition of 20% purple sweet potato extract and 2.5% carrageenan concentration. The results of this treatment showed an antioxidant activity (IC50) of 119.8800 μg/mL, overall acceptance of 5.6750 (slightly liked), hedonic taste of 6.0100 (liked), hedonic texture of 6.0550 (liked), hedonic aroma of 5.2600 (slightly liked), hedonic color of 4.1400 (neutral), hardness of 111.5000 gf, chewiness of 318.1550, gumminess of 132.5650, springiness of 2.4000, cohesiveness of 1.1900, moisture content of 18.8000%, color index of 1.9669 ºHue, total soluble solids of 35.00 ºBrix, reducing sugar of 7.8484%, pH value of 3.89, and ash content of 1.0927%. The best treatment (U4K1) was further tested for total plate count in red dragon fruit peel jelly candy.