Judul: Formulasi minuman fungsional kerang pisau (Solen spp)
Abstrak: Razor clam (Solen spp) is one type of a class of mollusks that includesbivalva Pelecypoda or non-fish aquatic biota. Razor clam have the opportunity to be used as a health beverage because it contains taurine and has an antioxidant activity. The aim of the study were to determine the effect of concentration and the mixing of the raw materials to the antioxidant activity in fungtional beverages and determine the maximum storage by testing the stability of the product. The result were three formultion, A131 formula (Solen spp 35%, ginger 40%, tamarind 15%, lemon 10%), A132 formula (Solen spp 40%, ginger 40%, tamarind 10%, lemon 10%), A133 formula (Solen spp 45%, ginger 40%, tamarind 5%, lemon 10%).Addition of razor clam, ginger, tamarind and lemon in formulation will provide a synergistic effect on antioxidant activity. Panelist preferred formula based on taste and has the best antioxidant activity (1.107,08 ppm) was the formula A131. Functional beverage powder storage for 60 days can reduce the antioxidant activity in functional beverage products to 8,7%. The testing stability of the parameters showed chemical and microbiological shelf life astimation based on the critical parameters of the mold, formula A131 has a shelf life over 94 days at 30⁰C.
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Judul: Formulasi dan Kestabilan Minuman Fungsional Berbasis Rumput Laut Cokelat (Sargassum sp.), Bunga Telang, dan Kayu Secang
Abstrak: Minuman rumput laut yang banyak diteliti sebelumnya hanya mengandung satu unsur rumput laut dan belum menggunakan tambahan rempah lokal. Manfaat kesehatan dan senyawa bioaktif pada Sargassum sp., bunga telang dan kayu secang berpotensi untuk dijadikan sebagai minuman fungsional ready to drink. Penelitian bertujuan untuk mendapatkan formula minuman fungsional berbasis Sargassum sp., bunga telang, dan kayu secang, sehingga didapatkan formula minuman yang mengandung antioksidan dan memiliki penerimaan sensori yang baik, serta memprediksi stabilitas minuman selama penyimpanan. Tahapan penelitian terdiri dari formulasi minuman fungsional dan pengujian kestabilan mutu. Hasil uji hedonik menunjukkan perlakuan komposisi Sargassum sp. berpengaruh nyata terhadap kesukaan panelis pada parameter rasa dan aroma. Formula F1 (jahe) memiliki tingkat penerimaan tertinggi dari panelis. Formula F1 memiliki nilai aktivitas antioksidan sebesar 9,93 ppm. Penyimpanan pada suhu ruang dan suhu chilling serta penambahan natrium benzoat dan natrium metabisulfit berpengaruh terhadap kestabilan mutu minuman fungsional selama penyimpanan., The seaweed drink that has been studied previously only possesses one element of seaweed and has not used additional local spices. The health benefits and bioactive compounds in Sargassum sp., butterfly pea flower, and secang wood have the potential to be mixed as ready-to-drink functional drinks. The study aimed to develop a mix-functional drink formula based on Sargassum sp., butterfly pea flower, and sappan wood, to obtain a drink formula that contains antioxidants and has good sensory acceptance, and evaluate the stability of the drink during storage. The stages of the research consisted of making functional drink formulations and analyzing quality stability. The hedonic test results showed that the composition of Sargassum sp. had a significant effect on the preference of panelists on the parameters of taste and aroma. F1 Formula (ginger) has the highest acceptance rate from the panelists. F1 formula had an antioxidant activity value of 9.93 ppm. Storage condition at room temperature and chilling temperature and the addition of sodium benzoate and sodium metabisulfite affected the stability of the quality of functional drinks during storage.
Keyword: antioxidant, formula, functional drink, Sargassum sp.

Judul: igenvalues and Eigenvectors of Tridiagonal Matrix with Non Constant and Recurrent Diagonal Entries.
Abstrak: Matriks tridiagonal adalah suatu matriks yang mempunyai entri-entri bernilai nol kecuali pada diagonal utama, di bawah diagonal utama (subdiagonal) dan di atas diagonal utama (superdiagonal). Entri pada diagonal utama tidak konstan dan berulang. Setiap entri pada matriks tridiagonal ini adalah bilangan kompleks. Dalam karya ilmiah ini, akan dibuktikan 3 teorema untuk menentukan nilai eigen dengan 2 kasus dan 1 teorema untuk menentukan vektor eigen. Teorema pertama menentukan polinomial karakteristik dari matriks tridiagonal. Polinomial karakteristik dari matriks tridiagonal tersebut digunakan untuk menentukan nilai eigen pada teorema kedua dan ketiga serta menentukan vektor eigen pada teorema keempat
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