Judul: Perubahan Karakteristik Fisikokimia Tepung Bawang Merah (Allium ascalonicum L.) dalam Kemasan selama Penyimpanan
Abstrak: The packaging has an important role to prevent and delay the decay of food. The used packaging will affect the chacteristic of packed shallot powder, the physically and chemically change is caused by chemical migration from packaging, aroma change, color change, and texture change due to water vapor and oxygen. These conducted research was designed to study and explore changes in physical dan chemical characteristics of shallot powder in packaging for storage in an effort to obtain a longer shelf life. Test parameters used in this study were color, water aktivity, moisture, ash content, concentration of total phenolics, and antioxidant activity. There were three conditions to store samples, i.e 20 oC, 30 oC, and 40 oC for 32 days. The results of this research of three packaging and temperature treatments during storage, has showed the increase and decrease of lowest slope on alumunium foil coated polypropylene vacuumed as parameters. iii On colorimetric measurement, water activity assay and water content assay showed the slope increase as 0.0942, 0.0042 and 0.0261 at temperature 20 oC, 30 oC, and 30 oC consecutively. The ash measurement, total phenolic concentration, antioxidant activity and inhibition precentation each has slope decrease as -0.0094, -4.2188, -0.9557 and -0.2924 on 30, 20, 30 and 30oC consecutively.
Keyword: Bogor Agricultural University (IPB), storage, shallot powder, packaging

Judul: Optimasi Bahan Pengisi dan Penstabil terhadap Antioksidasi Fisikokimia dan Organoleptik Tepung Bawang Merah (Allium ascalonicum L)
Abstrak: One way of preserving the fresh shallot is by processing it into the powderform. The purpose of this study is to optimize the addition of fillers ingredients and the stabilizer on the making process of Bima-variety of shallot (Allium ascalonicum L) powder to avoid damage on shallot in order to keep antioxidant containts and other quality parameters during dryng process. The optimization was conducted by Response Surface Methode (RSM). The selected formula is the fourth (4th) formula with addition of maltodextrin 0.65%, tapioca, 6.50%, and citric acid 225 ppm with the value yield 15.44 %, water content 2.63%, ash content 2.14%, fat content 0.45%, protein content 8.02%, crude fibre content 4.42%, vitamin C 150.23 mg/100g, total phenols 6327.42 ppm Gallic Acid Equivalence (GAE), antioxidant activity 902.71 ppm Ascorbic Acid Equivalent (AAE) with 94.74% inhibition of free radical. The best treatment according to the organoleptic-parameters is using addition of maltodextrin 1%, tapioca 10% and citric acid 300 ppm and the color of shallot powder based on the Hue°-value is a reddish yellow.
Keyword: Shallot (Allium ascalonicum L) powder, citric acid, tapioca, maltodextrin, Bogor Agricultural University (IPB)

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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