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Pathogenic bacteria are commonly found as natural contaminants in seafood and fish products. Globally, several countries have been imposing strict regulations on the maximum levels of pathogens and consequently require microbial testing of pathogens before the products can be marketed. A culture-based method with biochemical assay has been widely used to detect pathogenic bacteria in food, despite its long and extensive process. Meanwhile, the alternative molecular-based method to overcome this problem, cannot differentiate between viable and nonviable cells, which may lead to underestimation. This study aimed to develop a multiplex PCR (mPCR) method as a confirmatory assay for the culture-based method to detect pathogens in fish products simultaneously. This method applied a pre-enrichment step to ensure the growth of low-level pathogens and the injured cells in the sample. The target genes were ToxR, InvA, and UidA for Vibrio parahaemolyticus, Salmonella spp. and Escherichia coli, respectively. This assay also amplified the 16S rDNA gene of bacteria as an internal control for the PCR reaction. By implementing liquid-based DNA extraction during analysis, the developed-mPCR was comparable to detect the targeted bacteria in artificially-contaminated samples. The method was more sensitive in naturally-contaminated samples, where the number of E. coli, Salmonella spp. and V. parahaemolyticus detected were 28, 7, and 22, respectively. While the conventional method only detected 26, 5, and 19 of the respective pathogens. With a relatively shorter time and lower operation cost, the mPCR method is potential as an alternative for the culture-based method.

Indonesian salted-boiled fish (pindang) is a popular traditional food in Indonesia, which is made from Scombroid fish such as tuna and mackerel. As with other traditionally prepared fish products, pindang has important economic and social values, especially for those living in the coastal areas of Indonesia. However, pindang is a major cause of histamine fish poisoning (HFP) for consumers. Klebsiella aerogenes T124, a relatively high histamine-producing isolate from pindang, was used to describe lag time (λ), growth rate (μmax), maximum population density (Nmax), and histamine production in histidine broth and artificially contaminated Grey mackerel. Broth was adjusted to 1.5, 6, 10 and 20% w/v NaCl; mackerel was treated with 6% w/w NaCl, a level common to Indonesian industry practice, or not treated with additional NaCl. Samples were incubated at 10, 15, 20 and 30 °C. In broth, μmax and Nmax were significantly affected by temperature and NaCl, respectively, with λ influenced by both parameters. In control fish, μmax was significantly affected by temperature and NaCl, except at 10 and 15 °C; for 6% NaCl treatment, growth was only observed at 20 and 30 °C. Under similar incubation conditions for broth and fish, histamine formation was markedly affected by NaCl concentration. In broth, −5.1 to −6.6 log μg of histamine was produced per CFU, versus −4.6 to −6.6 log μg per CFU in fish. This study demonstrated that mackerel treated with 6% NaCl and stored at 10–15 °C prevents growth of K. aerogenes strain TI24 and formation of toxic levels of histamine.

Chitosan-starch blend film showed desirable elongation and oxygen transmission rate (OTR) values and demonstrated rapid degradation in soil burial treatment. The incorporation of higher glycerol concentration lowered tensile strength but increased the amount of transmittable water vapour. The biodegradability of chitosan-starch based film was tested using soil burial test. Chitosan-starch blend films were able to degrade naturally at slightly similar period, ranging from 72–87 days. The addition of glycerol was likely contributed to the high Water Vapour Transmission Rate (WVTR) value which faster the biodegradability of the film in soil. Among different type of acid solutions, lactic acid is less preferable solution to dissolve chitosan as it produced film with poor mechanical properties compared to acetic and formic acid. Based on its mechanical limitation, the film can be used as a coating based film for certain type of fish product, especially product with high lipid content.

Increasing fish consumption value should be supported by enhancing the safety and quality offish products. Microbiological level is most of importance since every food contains microorganismswhich could multiplicate due to temperature abuse and time delay during handling and processing.Risk assessment is a structurally and scientifically based approach aimed to protect consumerfrom risk (hazard) particularly microbiological hazard when consuming certain food. Microbiologicalrisk assessment of fishery products have not been structurally developed in Indonesia, eventhoughseveral initial data on hazard identification have been available. As an attempt to build an integratedrisk assessment, a model for microbiological risk of pathogenic Vibrio parahaemolyticus inshrimp will be proposed in this article. The available data could be used as a starting point whileother required data could be collected in collaboration with other related institutions.

Penelitian pembentukan formaldehid pada proses pembusukan ikan telah dilakukan untuk mengetahui proses pembentukan formaldehid secara alami dari ikan yang disimpan pada suhu dingin. Dalam penelitian ini, ikan kerapu (Ephinephelus fuscoguttatus) dalam keadaan hidup dimatikan dengan cara shock suhu dingin (hypotermia) selama 30‑60 menit atau sampai ikan mati . Kemudian ikan disimpan pada suhu 0‑4 0 C menggunakan es curai dan diamati setiap 2 hari sekali . Pengamatan dilakukan terhadap kadar formaldehid yang terbentuk, serta parameter lain seperti Total Volatile Base (TVB), kadar air dan mutu organoleptik. Hasil pengamatan menunjukkan bahwa formaldehid mulai terbentuk pada hari ke‑10 penyimpanan, sebesar 0,62 ppm, selanjutnya mengalami penurunan sampai akhir penyimpanan. Berdasarkan nilai TVB, ikan sudah tidak layak untuk dikonsumsi sejak hari ke‑10 penyimpanan dengan nilai TVB sebesar 49,77 mgN%, sedangkan berdasarkan hasil uji organoleptik, ikan ditolak oleh panelis setelah hari ke‑12 penyimpanan. Formaldehid pada kadar yang tidak terlalu tinggi (0,4‑0,6 ppm) yang terdeteksi pada ikan kerapu macan yang telah mengalami deteriorasi selama penyimpanan dalam es, diperkirakan terbentuk secara alami sebagai hasil dari proses pembusukan.