Due to halal and health issues, the fish by-product (waste) is one of the best sources to substitute land animal gelatin. Abalistes stellaris has a hard texture in skins and known as leather jacket fish species. Moreover, its skins obtained as wastes in smoked fish processing and have not been utilized. Therefore, this study aimed to analyze the physicochemical properties of gelatin extracted from A. stellaris skins at a different phosphoric acid concentration (0.2, 0.4, and 0.6 M). This study conducted by a completely randomized design (CRD) with three replications, followed by Duncan’s post-hoc test. The different pre-treatment of phosphoric acid concentrations showed significant differences (P<0.05) on yield, pH, chemical composition (moisture, protein, fat, and ash), gel strength, gelling, and melting points of A. stellaris skins gelatin. Only the viscosity parameter and an ash content of gelatin did not show a significant effect (P>0.05). The yield of A. stellaris skins gelatin ranged from 9.48% to 10.87%. The protein, moisture, fat, and ash content of skins gelatin ranged 74.55-81.41, 8.62-12.40, 0.43-0.73, and 1,48-1,79 (dry weight basis), respectively. Also, the gel strength and viscosity of skins gelatin were in the range of 1.28 N to 2.45 N and 3.83 cP to 4.21 cP. The amino acid composition of A. stellaris skins gelatin was rich in glycine, proline, alanine, and glutamic acid.

Starry trigger fish skin (Abalistes stellaris) is generally considered as waste from fish processing industry, especially in the traditional smoked fish industry. The purpose of this study was to determine the effect of different acid concentrations, used in the immersion process, on the physicochemical characteristics of starry trigger fish skin gelatin. Various concentration of acetic acid (0.2 M; 0.4 M; and 0.6 M) was applied during the gelatin soaking process. The experiment was done in triplicate. The extraction process was carried out for 4 hours at temperature of 55°C. The results showed that different concentration of acetic acid used in the soaking process had a significant effect (p<0.05) on the water, protein, and ash contents, yield, viscosity, gel strength, gelling point, and melting point. The results showed that the higher concentration of acetic acid used during the soaking process would affect the physical and chemical characteristics of gelatin from starry trigger fish skin (Abalistes stellaris).

Protease is an important enzyme widely produced by microorganisms applied in food, health, and industry. Mangrove ecosystem, a rich microorganism habitat, accounted as a new resource for isolating the proteolytic bacteria. The purpose of this study was to identify protease-producing bacteria from mangrove ecosystems in the Tuban area, Indonesia. Three isolates that produced the gelatinase was successfully isolated from mangrove sediments. Bacterial isolates were then tested for extracellular gelatinase. The results showed that isolate T1 had high gelatinase activity. Two isolates (isolates T2 and T3) produced moderately gelatinase enzymes. Molecular identification revealed that isolate T1 is Enterobacter hormaechei.

Gelatin is a fibrous protein obtained by partial denaturation of collagen. Traditionally, gelatin derived  from mammals’ skins and bones, such as cow and pork. However, both mammals’ gelatin could risk for bovine spongiform encephalopathy (BSE) and foot mouth disease (FMD), besides, gelatin extracted from pork is prohibited in Islam rules. Therefore, fish processing waste is potential as a source of gelatin in terms of starry triggerfish (Abalistes stellaris) skin gelatin. The aims of this study is to characterize physichochemical of gelatin extracted from skin of starry triggerfish. The methods used in this research, experiment with completely randomized design (CDR) by soaking different concentrations of citric acid (0.2; 0.4; and 0.6 M). The results showed that the concentrations of citric acid  had significantly different (P<0.05) on the yield, viscosity, gel strength, and fat content of starry triggerfish skin gelatin. On the other hand, the pH, melting point, galling point, protein, moisture, and ash value of starry triggerfish skin gelatin did not perform significantly different (P>0.05). The most properties of starry triggerfish skin gelatin meet the commercial gelatin, and it is able to as a potential alternative of halal gelatin.

Doktor Mengabdi is a community service program at Universitas Brawijaya that is carried out to improve the welfare of the community. One of the efforts to help the community in completing its packaging is by providing assistance in the form of business equipment. The purpose of this study is to investigate the difference in income of Small medium enterprises, Lele Sehat (IGF) which has been provided with the help of vacuum frying and spinners machines. Data retrieval was done through interviews and live observations. The data were tested for its normality and further analyzed using a paired t-test. The results showed that there was a difference in income of small-medium enterprises difference between before and after getting tool assistance. Prior income was IDR 3,007,000. It was increased to IDR. 4,097,000. This indicates that providing tools to small-medium enterprises will increase income and indirectly improve their welfare