Judul: Pengaruh Suhu Terhadap Laju Respirasi dan Produksi Etilena pada Pascapanen Buah Manggis (Garcinia mangostana L)
Abstrak: The Mangosteen is one of climacteric fruit plant that has thick and fragile rind, the kernel is white color, nutrient content and of presenting it’s red-purple colored fruit and interesting. The fruit which has a fast respiration rate and high ethylene production usually has short shelf-life. The purpose of this research was to evaluate affect of temperature on respiration rate and ethylene production of mangosteen fruit. Respiration rate CO2 and O2 were measured by gas analyzer and ethylene production was analyzed gas chromatography. The results of this research revealed that the peak of climacteric at room temperature occured on 11th day with respiration rate of 54.56 ml/kg.hour and for cold temperature happened on 22nd day with respiration rate of 36.68 ml/kg.hour. The research showed that the highest ethylene on the room temperature pointed on 247.29 ppm (11th day). The research showed that the highest ethylene on the cold temperature pointed on 50.44 ppm (21st day). At room temperature (27-300C), mangosteen will be faster ripend and has a shorter shelf-life compare to the mangosteen which stored on the cold temperature (150C).
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Judul: Physiological study of hardening and color changes of pericarp in relation to climacteric respiration and moisture content in mangosteen (Garcinia mangostana) after harvest
Abstrak: Mangosteen is a high economic value fruit in Indonesia. The problems encountered are the fruit pericarp quickly harden and the color immediately changed to dark purple-black, and sepals quickly turned into brown in color after harvest, so shelf life is short, especially at room temperature. This research aimed to study the process of change in hardness, pericarp and sepal color, and the sepal freshness of the mangosteen fruit and the factors that influence the physiology and biochemistry during storage. The research consisted of five experiments: (1) hardening physiology of mangosteen pericarp, (2) effect of exogenous ethylene and storage temperature on quality changes of mangosteen, (3) effects of 1-methylcyclopropene (1-mcp) and storage temperature on hardening of and color change of pericarp of mangosteen, (4) Effect of cytokinin and CoSO4 on physical quality of mangosteen during cool storage, and (5) Effect of coating material and cytokinin CPPU (N-(2-chloro-4-pyridyl)-N-phenylurea (Forchlorfenuron)) on the quality of mangosteen on cool storage. The results showed that the peak rate of ethylene production one day earlier than the respiration climacteric. The peak rate of ethylene production occurred on day 11 while the respiration climacteric peak occurred on day 12. Climacteric respiration will lead to biochemical changes in the mangosteen fruit pericarp, such an increase in protein content, increased activity of the enzyme phenylalanine ammonia lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), and peroxidase (POD), and increasing the amount of lignin. Pericarp hardening occured due to water content decrease in the mangosteen and increased content of lignin. Fruit stored at a temperature of 15oC can last up to 28 days after treatment (DAT). Whereas fruit stored at room temperature only last up to 14 DAT. Mangosteen fruit stored at a temperature of 15oC had lower level of resistance and hardness. had a higher water content, lower weight loss, slower color change, and had a higher total soluble solids (TSS) and titratable acidity (TA). Exogenous ethylene treatment did not provide a marked influence on all the variables observed, which means that the mangosteen fruit wass less sensitive to exogenous ethylene treatment. 1-MCP treatment at various doses did not prolong the shelf life of the mangosteen fruit. This treatment is consistent in both room temperature and at a temperature of 15oC. 6% beeswax better reduce weight loss than other types of coating materials.
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Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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