Judul: Kajian Karakterisasi Permen Jeli dari Campuran Rempah – Rempah dan Penentuan Umur Simpannya
Abstrak: The demand for healthy food tends to increase every year along with the growth of public concern on health. Foods consumption, include jelly candy, is not only for daily nutrition needs but also for improving body health. Jelly candy has potency to be developed as a functional food contained dietary fiber, and enhance the flavor and functional properties by adding spices extract mixture. This study aims to obtain a selected jelly candy formulation made from carrageenan and konjac with a spices flavor and determine the physicochemical properties and functional characteristics of the selected product. Furthermore, selected jelly candy shelf life was determined by modified critical moisture content method. In first step, two formulas of spices extract mixture (formula A and formula B) were made. Formula A contained ginger, sappan wood, cinnamon, long pepper and lemongrass while formula B consisted of nutmeg, black pepper, anise, cloves and pandan leaves. These two formulas were used by combining concentration of mixture in 10, 15, and 20%. The jelly candies were coated by edible film which is made from carrageenan. Based on hedonic rating test results, antioxidant capacity and total phenolic compound, selected formula A was jelly candy with 15 % and the formula B was 20 % of added spices extract. Formula A with 15% spices extract had antioxidant capacity of 360.67 mg AEAC/g, total phenolic compound 96.43 mg GAE/g, 4.37 g of total carbohydrate and 0.37 g of dietary fiber per serving (4.5 grams). Formula B with 20% spices extract had 229.46 AEAC of antioxidant capacity, total phenolic compound 317.80 GAE, 4.43 g of total carbohydrate and 0.36 g of dietary fiber per serving (4.5 grams). Shelf life of selected jelly candy at RH 80 % storage using oriented polypropylene (OPP) plastic packaging showed that formula A was 4.4 months and formula B was 4.6 months. This jelly candy had potency to be developed as a functional food because of its dietary fiber content and antioxidant capacity.
Keyword: antioxidant, spices, conjac, carrageenan, jelly candy

Judul: Pendugaan Umur Simpan Permen Jelly Pepaya (Carica papaya L).
Abstrak: Papaya (Carica papaya L) is a kind of fruits which is concluded in Caricaceae family. This fruit is a yearly fruit so it exists for a whole year. It is needed to make some efforts in order to utilize papaya, then it will increase the economic value of papaya. One of them is by making processed product from papaya, for example papaya jelly candy. The general aim of this research was to produce papaya jelly candy. The special aim of this research was to know the quality changing during storage, also predict shelf-life of the product, and to know the best packaging for the product of papaya jelly candy. Shelf life is time that is needed for a product in a certain storage condition to get into a certain level of quality. Shelf life is determinated by using accelerated storage studies (ASS) method. It was done by using such condition that could accelerate the degradation process of quality of the product. The packaging and storage condition is assumed could lengthen product’s shelf life and suppress degradation rate of papaya jelly candy. In this research, papaya jelly candy was packed in three different packaging. Those were polypropylene (PP) plastic, aluminum foil and glass packaging. Storage was held at 5, 15, 25, and 35˚C. This research consists of three stages. Firsting, the material preparation and making of papaya jelly candy. Second, packing and storage papaya jelly candy in different packaging and storage temperature. Third, analysis quality product. Material characterized before treatment, with proximate and microbial analysis. Proximate analysis consisted of water, ash, protein, fat, high fiber content, carbohydrate, pH, and aw. Microbial analysis included mold analysis of papaya jelly candy. Besides that, there was another analysis to know material characterization during storage. Those are water content, total titrated acid, vitamin C content, texture, color analysis, and sensory evaluation test. Based on the research result, it was known that quality of papaya jelly candy was changing during storage. Water content of papaya jelly candy was increasing in every packaging and at every temperature of storage. Water content increased in PP plastic packaging at 5, 15, 25, and 35°C, were 0,11, 0,13, 0,16, and 0,17% respectively per day. Water content increasing of papaya jelly candy in aluminum foil packaging at 5, 15, 25, and 35°C were 0,08, 0,10, 0,13, and 0,14% per day. While water content increasing of papaya jelly candy in glass packaging the same temperature were 0,12, 0,15, 0,15 and 0,19% per day. Vitamin C content and Total Titrated Acid of papaya jelly candy decreased 0,01% per day in all of packaging and all storage temperature.
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Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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