Judul: Evaluation Of Active Edible Coating From Chitosan Incorporated With Thai Herb Extract For Fresh-Cut Guava (Psidium Guajava L.)
Abstrak: Fresh-cut guava is one example of convenient novel foods that fit the many needs of modern lifestyle while it is also very perishable. Thai Herb extract might have antimicrobial activity as one of an alternative for prolonging shelf-life of fresh-cut product. Objectives of this research are study antimicrobial activity of Thai Herbs and application of active edible coating from chitosan incorporated with Thai Herb extract on fresh-cut guava (Psidium guajava L.) during storage. Screening of Thai Herbs, extracted with ethanol 50% and then dried with freeze drying method, for choosing the best one as an antimicrobial agent in edible coating was done by disk diffusion method. Total phenolic compound (TPC) and antioxidant capacity were analyzed using Folin-Ciocalteu method and DPPH scavenging activity respectively. Piper betle as selected Thai Herb extract had antimicrobial activity against Gram-positive and negative bacteria also yeast from 7.15±0.36 to 18.81±0.06 mm and TPC of 79.20±1.42 mg GAE/g sample also antioxidant activity of 674.59±1.48 μmol TE/g sample. The concentration of Piper betle extract used for formulation was determined according to minimum inhibitory concentration (MIC) with broth microdilution method and minimum bactericidal concentration (MBC). Highest MBC value was 12.5 mg/mL and concentration of extract used for coating solution was 25 mg/mL. Application of coating from chitosan incorporated with Piper betle extract for fresh-cut guava did not reduce amount of microbial growth until 6.37±0.21 log CFU/g at the end of storage and could not inhibit browning reaction as shown by L (62.28±4.45), a* (2.32±2.90), and b* (17.41±0.51) value. This coating process could not delay ripening process according to total titratable acidity (0.07±0.03 g citric acid/100 mL), total soluble solid (7.27±0.45°brix), and weight loss (0.12±0.01%). It also had the lowest hedonic score compared to control in sensory evaluation at day 8 for attributes of appearance (2.1±0.99), texture (3.9±1.73), aroma (2.9±1.37), and overall (2.8±1.23).
Keyword: chitosan, coating, fresh-cut guava, Piperaceae, Thai Herb

Judul: Shelf life and quality of edible coated fresh cut sapota (Achras zapota, L) cultivar sukatali ST1 stored in modified atmosphere packaging
Abstrak: Minimally processed fruit is one of the options that provide practical and ready to eat food for the urban people that has instant life style. Edible coating and low temperature are required to keep the quality and the shelf life of the minimally processed fruits. The objective of this study was to determine the influence of edible coating used for fresh cut sapota cultivar Sukatali ST1 on its quality and shelf life. Preliminary experiment resulted in the selection of 0.5% glucomannan out of 0.5%, 0.55%, and 0.6% concentration for the edible coated fresh cut sapota due to its lowest respiration. Two treatments, storage temperature at three levels 5oC, 10oC, 15oC and atmosphere composition at also three levels 16-18% O2 & 2-4% CO2, 14-16% O2 & 2-4% CO2, and 14-16% O2 & 4-6% CO2 were applied to the edible coated fresh cut sapota cultivar Sukatali ST1. The results indicated that storage temperature of 10 oC, and atmosphere composition of 14-16% O2 and 2-4% CO2 were favored compared to the room condition. The packaging films appropriate for the selected condition were stretch film and polypropylene film. The validation experiment concluded that edible coated fresh cut sapota cultivar Sukatali ST1 was best to be stored at 10 oC in a modified atmosphere packaging using stretch film, which was still accepted by consumers on the sixth day storage with an organoleptic score of 3-5 in the range of
Keyword: 

Judul: Formulasi Hamiltonian untuk Menggambarkan Gerak Gelombang Soliter Dimensi Tiga di Permukaan Laut
Abstrak: Gelombang permukaan adalah gelombang yang terjadi perbedaan rapat massa antara air dan udara. Salah satu gelombang permukaan yang ditinjau adalah gelombang soliter. Formulasi gelombang soliter dilakukan dengan menggunakan formulasi Hamiltonian.
Keyword: