Judul: Karakterisasi Flavor Buah Naga Putih (Hylocereus undatus) dan Buah Naga Merah (Hylocereus polyrhizus)
Abstrak: Pitaya is one of newcomers on market. It is also one genus of the cactus family that is unique and interesting to be more deeply explored. Pitaya market demand increases every year. This is correlated with consumer demand for pitaya flavor in a variety of food products. Therefore, this study took the domain about flavor characterization of white and red pitaya to characterize their sensory description and their volatile composition. This research was divided into two stages. The first study involved the selection and training of panelists, pitaya flavor extraction, selection of extraction methods with sensory evaluation, and QDA (Quantitative Descriptive Analysis). The extraction was done using two methods, the maceration and the Likens-Nickerson. The second study included extraction of volatile components that form pitaya flavor using method that had been selected and identification using GC-MS. Based on trained panelists’ evaluation, some fruit aromas description in both of pitayas were sweet, fruity, floral, green leafy, fatty green, and plastic green. Trained panelists revealed in QDA test that the most intense aroma in both of pitayas is green leafy. According to output data from identification result using GC-MS, white and red pitaya contain alcohols, carboxylic acids, alcanes, aldehydes, ketones, alcenes, esters, and terpenoids as their volatile compositions. Alcohol compounds present as major concentration in both of pitayas, with most of this being due to 1-tetradecanol (143.40 μg/g) in white pitaya and 1-hexadecanol (114.62 μg/g) in red pitaya. These volatile compositions had correlation with FGD sensory description. It is expected that the results of this research can contribute significantly to world food and flavor.
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Judul: Profil Komponen Volatil Minyak Atsiri Kayu Putih dari Berbagai Daerah dan Pengaruhnya terhadap Profil Flavor Cajuputs Candy.
Abstrak: Essential oils of cajuput and peppermint have been utilized as bioactive components and flavor. Volatile components influence the flavor quality. The cultivation and production of cajuput essential oils are spread over Indonesia regions such as Java, East Nusa Tenggara, and Sulawesi. This study was conducted to determine the profile of cajuput essential oils from various regions in Indonesia related to their application compatibility into Cajuputs candy products. The quality of cajuput essential oils were analyzed for their physico-chemical properties including of color, density, refractive index, optical rotation, solubility in alcohol 70%, and cineol content. The composition of the volatile components were analyzed by using GC-MS. Sensory evaluation was done in terms of its acceptance by rating hedonic test and the similarity of its sensory character to commercial Cajuputs candy by different from control test. Physical and chemical properties measurement showed that the density, refractive index, and solubility in alcohol 70% of all samples had adjacent values, whereas in terms of color, optical rotation, and cineol content had diverse values. Cajuput essential oil that came closest to the target in term of physico-chemical characteristic was oil from Pulau Buru. The cajuput essential oil chromatogram pattern of Sukabumi, Indramayu, Gundih, Mojokerto, and Pulau Buru were similar while the chromatogram pattern of Atambua and Madura were somewhat different. No conclusion regarding the compatibility of evaluated essentials oils into the Cajuputs candy could be made yet due to the weakness of sensory evaluation method.
Keyword: Cajuputs candy, essential oils of cajuput, flavor, GC-MS, sensory

Judul: Solusi Geometri Schwarzschild untuk Dimensi 4+1 dengan Invarian Rotasi Isotropik
Abstrak: Metrik Schwarzschild merupakan solusi eksak pertama dari persamaan medan Einstein dengan mangasumsikan metrik statik dan simetris. Metrik Schwarzschild yang ditemukan oleh Karl Schwarzschild masih dalam dimensi 3+1, namun seiring dengan teori-teori terbaru yang menunjukkan bahwa alam semesta tidak hanya di dimensi 3+1. Maka melalui penambahan dimensi, tujuan penelitian ini memperoleh solusi pada geometri Schwarzschild untuk dimensi 4+1 dengan memodifikasi koordinat bola yang invarian rotasi isotropik dan melalui penurunan rumus seperti koordinat bola, simbol Christoffel, dan tensor Ricci. Selain mendapatkan solusi ini, metrik Schwarzschild dimensi 4+1 dapat digunakan sebagai metrik dasar untuk memperoleh solusi blackhole dan wormhole pada dimensi 4+1. Hasil akhirnya, dengan memanfaatkan modifikasi koordinat bola, metrik Schwarzschild dapat dibentuk sehingga diperoleh solusi geometri Schwarzschild untuk dimensi 4+1.
Keyword: metrik Schwarzschild, persamaan medan Einstein, modifikasi koordinat bola, penambahan dimensi, invarian rotasi isotropik