Judul: Pembuatan Permen Jelly dari Karagenan dan Konjak dengan Aplikasi Prebiotik Xilo-Oligosakarida
Abstrak: The functional food’s consumption is growing rapidly. One of the functional ingredients is Xilo-oligosaccharides (XOS). In this study XOS was added to jelly candy which used carrageenan and konjac as gelling agent. Carrageenan and konjac was used as alternative gelatin substitute. The objective of this research is to study the influence of gelling agent (carrageenan, konjac, mixture of carrageenan and konjac), ratio of carragenan and konjac (1:1, 2:1, 3:1) and concentration of xilooligosaccharide used (3%,4%, 5%) to the physical and sensory characteristics of jelly candy. This research is divided in two steps, preliminary and main research. Preliminary research consists of formulation and selection of the best formula for the main research. The best formula is formula with 1.5% gelling agent, 20% sugar, 5% glucose, 0.2% citric acid, 0.1% flavor, 0.001% colorant, 73.2% water and sugar coating. Main research consists of texture, sensory, proximate, and XOS content analysis. The optimum jelly candy from texture and sensory analysis is jelly candy with mixture of carrageenan and konjac (1:1) and 5% XOS. The jelly candy has the hardness of 166.28 gf, elasticity 1.00, and stickiness 132.95 gf. The result of proximate analysis showed that jelly candy has 10.37% water content, 0.35% ash content, 1.00% fat content, 0.96% protein content, and 87.32% carbohydrates content (by difference). The XOS anlalysis show that the jelly candy contain 15.17% XOS.
Keyword: 

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: 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
Keyword: