Judul: Pengaruh Suhu dan Lama Perendaman Blansir Terhadap Mutu Selada Kepala (Lactuca sativa L.) Terolah Minimal Selama Penyimpanan
Abstrak: The damage of minimally processed head lettuce (Lactuca sativa L.) is because of the activities of enzymes and microorganisms. The objectives of this research were (1) to determine the effect of treatment on quality of shredded blanched-lettuce, (2) to determine the best combination of temperature and immersion time on the handling of shredded blanched-lettuce and (3) to determine the Standard Operational Procedure (SOP) to treat minimally-processed lettuce head. The results of this research were blanching temperature of 50 °C with immersion time of 55 seconds and vacuum packaging could maintain the quality (weight, water content, brightness, hardness, and organoleptic) shredded blanched-lettuce could until 8-day storage. Standard Operational Procedure (SOP) for handling the shredded lettuce is sorting and peeling brown leaves, cuting and shredding with a size of 1.5 cm, immersing in water at 50 °C for 55 seconds, submerging in cold water 3-5 ° C for 1 minutes, centrifuging to reduce the excess water on the surface of shredded lettuce, packing with HDPE plastic, packaging in vacuum, and storaging with a temperature of 5 oC.
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Judul: Pengaruh Pelapis Lilin Lebah terhadap Perubahan Mutu Selada (Lactusa sativa) Terolah Minimal Selama Penyimpanan
Abstrak: Minimally processing in lettuce could accelerate senescense. Hence, the research objectives are to know the effect of beeswax emulsion coating on the quality of minimally-processed-lettuce and determine the best storage condition. The research design used Completely Random Design while the first factor was beeswax concentration: 0, 1, 3, and 5 %, second factor is temperature with level 3-4 °C dan 7-9 °C and third factor was storage days: 3, 7, 10, and 14th. The result showed that the beeswax concentration affects significantly (P<0.05) on the drop weight and damage rate, but there is no interaction between both of them. Ascorbat acid in temperature II sigfinicantly is less than temperature I while acid total tend to be stabil in 3 % concentration beeswax coating. In sensory evaluation, lettuce with 5 % beeswax concentration and 7-9oC temperature almost have the highest score among the other lettuces, but is not significantly different to 3 % beeswax concentration in the same temperature for some parametres. Inconclusion, to maintain the quality of minimally-processed-lettuce, it could be use 3 % beeswax coating with 7-9°C storage temperature and RH 85%.
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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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