Judul: Pengaruh Pelapisan Kitosan terhadap Daya Simpan Buah Pisang Ambon
Abstrak: The banana needs post harvest treatment to be not decay quickly. One of the way is by coating. Chitosan is a substance that can be used to coat the fruit, which is a polysaccharide derived from shrimp and crab shell waste. The aims of the research was to study the effect of chitosan coating on post harvest of bananas, and find out the optimal concentration of chitosan as a natural coating materials. This research used the completely randomized design (CRD) method with one factor. The factor was the chitosan coating by three level treatments with different concentrations. First concentration was 0%, second was 1%, and the last was 2% w/v. Each treatment was repeated four times. The results showed that treatment with concentration of chitosan couldn’t inhibit loss of. There is no consistent effect of chitosan on acid titration, vitamine C content and no significant effect on total soluable solute. From organoleptic test that was conducted in 12 day after treatment indicated that respondent still like bananas on 2% concentration of chitosan treatment.
Keyword: weight loss, banana, self life, total soluable solute, total titration acid

Judul: Penggunaan Kitosan dan Lilin Lebah sebagai Bahan Pelapis untuk Meningkatkan Masa Simpan dan Mempertahankan Kualitas Buah Pepaya
Abstrak: Papaya is a climacteric fruit with increased respiration rate during ripening process. Respiration rate papaya can be inhibited by providing a coating on the surface of the fruit. Coating materials that can be used include chitosan and beeswax. The purpose of this research is to study the effect of chitosan and beeswax coating on the shelf life and quality of Callina papaya fruit during storage. Experiment was carried from November 2014 until March 2015 at the Experimental Field of PKHT, Tajur and Postharvest Laboratory, Department of Agronomy and Horticulture, Faculty of Agriculture, Bogor Agricultural University. The experimental design used was completely randomized design with 3 treatments and 3 replications, there are chitosan 0.75%, beeswax 6%, and the control (without coating). Data were analyzed by F test and treatments that affect were analyzed by Duncan Multiple Range Test (DMRT). Parameters measured were shelf life, the index of fruit skin color scale, respiration rate, weight loss, skin firmness, pulp firmness, total soluble solids, total titratable acids, and the content of vitamin C. Results of the experiments showed that chitosan and beeswax treatments can extend the shelf life of papaya Callina 4–5 days compared to control because it inhibits respiration rate papaya during storage. The use of chitosan and beeswax can maintain the physical and chemical quality of papaya fruit Callina.
Keyword: Callina, chemical quality, physical quality, postharvest ripening, respiration rate

Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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