The pipette method is a conventional method commonly used for determining the viscosity of gelatin. The purpose of this research was to study the use of a rotational viscometer to measure the viscosity of fish gelatin. The rotational viscometer has a wide measuring range and a limitation on low viscosity liquid measurements such as fish gelatin, so it is necessary to verify the sensitivity of the rotational viscometer to measure the viscosity of fish gelatin. In this study, low range manual rotational viscometer (MLV), low range digital rotational viscometer (DLV), low range digital rotational viscometer with low viscosity adapter (DLV + UL) were tested for their sensitivity to read standard solutions of 4.8 cP and 48.8 cP. The results showed that DLV + UL generated a high accuracy in reading 4.8 cP and 48.8 cP standard solutions with the recovery value of 102.5% and 99.5%, respectively. Measurement of the viscosity of commercial fish gelatin seven times obtained a coefficient of variance of 2.98% indicating a high degree of precision, with a recovery value of 103.54% of the value of the secondary reference material analysis certificate. The number of samples required for DLV + UL is 16 mL, while the conventional method required a sample of 100 mL. We proposed using DLV + UL for testing the viscosity of fish gelatin.

Thermoplastic agar/chitosan blend was prepared by a rheomix process, and the effect of concentration agar: chitosan on the material properties forms were investigated. This research aimed to observe the physical properties of bioplastic agar/chitosan produced through rheomix. Bioplastic was produced by mixing 65 % solid material (agar: chitosan) and 35% glycerol, the ration through the melting process at an initial temperature of 100°C. The weight ratio of agar : chitosan was 65% : 0% (F0/control), 52% : 13% (F1), 39 % : 26% (F2), 26 %: 39% (F3). The tensile strength and elongation of bioplastic were decrees with a higher chitosan concentration. The color and the opacity of bioplastic were affected by the ratio of agar: chitosan. The moisture content and the water vapor transmission rate (WVTR) of bioplastic were increased by increasing the chitosan ratio. The SEM micrograph of bioplastic showed that the blend agar and chitosan seem to have a rough and inhomogeneous surface than pure bioplastic agar. The best blend was bioplastic with agar: chitosan 52%: 13% (F1), which have properties of : tensile strength 4.95 ± 0.56 MPa, elongation at break 34.94 ± 0.99 %, moisture content 15.33 ± 0.43%, WVTR 3259.39 ± 28.12 g/m2.24 h.

Padina sp. seaweed is a species of brown seaweed that grows naturally in Indonesian waters and it is not been optimally utilized. Padina sp. contains bioactive natural carotenoids that can apply as additive ingredients in functional foods and cosmetics field. This study aimed to determine the total carotenoid content in Padina sp. seaweed-infused oil. Seaweed oily extract or Padina sp. seaweed-infused oil was obtained from the filtered maceration of Padina sp. powder using virgin coconut oil as a solvent. Furthermore, the total carotenoid content in Padina sp. seaweed-infused oil, Padina sp. powder and virgin coconut oil as solvent for maceration of Padina sp. were analyzed using the spectrophotometry method. Padina sp. powder and virgin coconut oil without Padina sp. (as control) contained total carotenoid content 2.42±0.32 µg/g and 0.71±0.66 µg/g respectively. Padina sp. seaweed-infused oil had total carotenoid content by maceration process with virgin coconut oil as solvent at a temperature of 65 °C for 1 hour, 3 hours, and 5 hours were 2.73±0.36, 2.18±1.01, and 1.74±1.24 µg/g respectively. Therefore, the total carotenoid content increased in Padina sp. seaweed-infused oil. It could be an opportunity for functional food products and cosmetic ingredients.