Judul: Studi enkapsulasi Lactobacillus casei dan Bifidobacterium longum dengan teknik ekstrusi
Abstrak: Lactobacillus casei dan Bifidobacterium longum merupakan bakteri probiotik yang umumnya diaplikasikan sebagai starter kering probiotik untuk pangan. Proses pengeringan dalam pembuatan starter kering dapat menurunkan jumlah L. casei dan B. longum, oleh karena itu perlu dilakukan enkapsulasi. Teknik enkapsulasi yang digunakan dalam penelitian ini adalah ekstrusi dengan maltodekstrin-alginat (1:3), pati sagu-alginat (1:3), maizena-alginat (1:3), dan kontrol skim-alginat (1:2) (b:b) sebagai bahan pengkapsul. Keempat bahan pengkapsul tersebut berpengaruh nyata terhadap nilai viabilitas, efisiensi enkapsulasi, jumlah sel pada beads basah dan beads kering, ketahanan sel setelah proses pengeringan, serta ketahanan sel L. casei dan B. longum terhadap kondisi pH rendah dan garam empedu. Berdasarkan nilai viabilitas L. casei dan B. longum, karakteristik matriks beads, jumlah sel pada beads basah dan beads kering, serta persentase ketahanan sel selama proses pengeringan, bahan pengkapsul maltodekstrin-alginat lebih baik dibanding pati sagu-alginat dan maizena-alginat, namun belum lebih baik dari bahan pengkapsul kontrol yaitu skim-alginat. Jumlah sel L. casei dan B. longum pada beads kering maltodekstrin-alginat adalah 4.69 ± 0.08 log CFU/g dan 5.32 ± 0.21 log CFU/g, sedangkan jumlah sel L. casei dan B. longum pada beads kering skim-alginat lebih tinggi yaitu 5.08 ± 0.07 log CFU/g dan 6.20 ± 0.16 log CFU/g.
Keyword: Bifidobacterium longum, Encapsulation, Lactobacillus casei, Probiotic, Starch, Starter, Food science, Drying process

Judul: Enkapsulasi Lactobacillus casei dengan teknik ekstruksi sebagai starter untuk pembuatan dadih susu sapi
Abstrak: The purpose of this research is to get an optimal composition for encapsulating materials of Lactobacillus casei as dried starter culture for production of dadih from cow milk. Lactobacillus casei was encapsulated by the extrusion technique, then dried by hot air oven on 40 oC. Biopolymer for encapsulating materials consist of sodium alginate and filler based on protein such as whey protein concentrate, sodium caseinate, and skim. The highest yield, the biggest diameter, and more spherical shape of beads was recorded in 4% alginate beads. Yield and diameter of beads decreased significantly with increasing filler concentration. Optimum proportion of alginate-filler on 4% total biopolymer is 2:1 (2.67% sodium alginate : 1.33% filler) that resulted in yield 78.7 – 80.7%, diameter 2.7 – 2.8 mm, and spherical – elliptical shape of beads. Encapsulated Lactobacillus casei in 4% alginate beads and alginate-skim 2:1 showed that the rate of acid produced was higher then alginatewhey 2:1 and alginate-sodium caseinate 2:1. Encapsulation of Lactobacillus casei with alginate-skim 2:1 resulted in a higher cell viability, namely 5.32 log cfu/gram or decline in viable count of about 2.36 log over a drying periode of 6 hour while there was a decline of about more than 5,76 log in Lactobacillus casei which were encapsulated with 4% alginate (without filler). Using dry starter (encapsulated Lactobacillus casei) for production of dadih from cow milk took longer time (48 hours) as compare to free cell (24 hours) on the same population of Lactobacillus casei. The characteristics of dadih from cow milk with dried starter application resulted in viscosity 2147 – 2563 cP, pH 5.55 – 5.75, titrable acidity 0.64 – 0.67%, and population of Lb. casei 8,16 – 8,43 log cfu/m . Population of Lactobacillus casei on dried starter in this study still low, namely 2.1 x 105 cfu/gram, and hence continuation experiments need to be increasing population of Lactobacillus casei in alginate-skim beads.
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Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite