Effect of Water Temperature on the Depletion of Eugenol in Sea Bass under the Simulated Settings in Handling and Transport

The edible safety of eugenol-treated fish is one of the concerns limiting the anesthetic applied in the aquaculture industry. The depletion of eugenol was investigated at different water temperatures under the simulated settings of sea bass handling and transport. Sea bass was exposed to eugenol at a concentration of 60 mg/L for 3 min, then immediately transferred to clean water to be purged for 24 h and sampled at different time intervals. The left fish were re-exposed to eugenol in a repeat of the first exposure, purged for 48 h in clean water, and sampled for eugenol detection. Under the simulated settings, the sea bass could accumulate more eugenol residue in fillet when exposed to water at a temperature of 20 °C than that at 13 °C. However, eugenol could be depleted much faster when the sea basses were exposed to the higher water temperature. The half-lives of eugenol in sea bass were 0.28 h and 0.29 h for the first and second purging stage at a water temperature of 20 °C, while at 13 °C, the half-lives were 2 and 4.5 h, respectively. Therefore, increasing the water temperature may be an effective way to accelerate eugenol depletion in fish fillet and reduce exposure risk for the consumer.

Characterization of tannin based colorimetric indicator and its application on fish packaging

This study aims to determine characteristics of the gel-type colorimetric indicator at various pH and under different storage conditions, then determine the indicator characteristic in the packaging of fish fillets during storage. The gel-type color indicator was synthesized with a concentration of 1%, 3%, and 5% gambir powder. The FT-IR spectra of the color indicator showed the presence of tannin functional groups, namely C=C aromatic rings, C-C phenolic, and C-H groups, respectively at wavenumbers 1517-1519, 1440-1475, and 752-761 1/cm. Moreover, the coefficient value of the Red-Green-Blue (RGB) of the indicator was changed over pH and did not appear to be consistent. Based on the Analysis of Variance (ANOVA) test, the concentration of gambir powder and duration of color indicator storage, respectively, had a significant effect (P <0.05) on the value of the RGB coefficient. The color indicator exposed to sunlight had a smaller RGB coefficient value than the RGB coefficient value of the indicator stored at room temperature and 5-7°C. The application of color indicators with a 1% Gambir powder concentration in fish fillet storage has been tested for 5 days at a temperature of 5-7°C. They showed that the RGB coefficient value of the indicator was proportional to changes in the pH value of fish fillets but not in line with changes in Total Volatile Based Nitrogen (TVBN) of fish fillets.

Detection of Bacterial Contamination of Some Traditional Frozen Fish in Some Local Markets in Tikrit City

This study was aimed to investigate bacterial contamination in frozen fish form samples collected from some local markets in several neighborhoods of Tikrit city. Thirty samples of frozen fish were collected for two types of fish common carp and fish fillet, laboratory bacterial isolation and diagnosis showed Staph. aurues samples constitute highest proportion of isolations which followed by Aeromonaus hydrophyla, E.coli, Psudomonas. Spp and Salmonella ( 7,6, 5 and 3) isolations. Bacterial number of isolations has been calculated where it showed a variant in number of bacterial colonies, Staph. aurues which recorded the highest rate in colonies number. Chemical analyses to estimate the amount of protein and fat showed 9.43, 7.31% of protein and 3.9, 8.66 % fat, so as to moisture was high in both carp and elephant fish 80.5, 75.72% and ash 2.31, 7% in carp and fish fillet, respectively. The results of current study shows there are an inverse relationship between both used fish in study and the moisture in the fish.

Innovation Technology on Catfish Fillet By-Product as Raw Materials for Food Industry

Kampar Regency is one of the national catfish cultivation development clusters, and there are many catfish processing industries, especially fish fillet processing. The processing of catfish fillets always left by-products in the form of small pieces of meat, skin, bones, and abdominal fat, which amounts to around 50% – 60%. The by- products are mostly disposed to the environment around the industry, causing pungent odor pollution, as the byproducts contain protein, fat, minerals and crude enzymes which are suitable habitat for the growth of spoilage microbes. Therefore, it is very possible for these by-products to be processed further in order to obtain new products in the form of industrial raw materials that have economic added value. The objectives of this research are (1) Optimizing the utilization of by-products from fish fillet processing starch into raw materials for food industry that have economic value; and (2) understanding the characteristics of organoleptic quality and the proximate composition of the food industry raw materials produced. The research method used is an experimental method, namely experiments on processing by-products into raw materials for the food industry in the form of fish meal, fish oil and bone meal. The results showed that the number of by-products produced from processing the catfish fillets was arround 60% with, consisted of head, tailbone and fins by 37%, small pieces of meat 5%, viscera 10% and abdominal fat 8%. Furthermore, that raw materials having organoleptic quality and proximate composition that meet the SNI standards.

Comparative Fatty Acid Profiling of Edible Fishes in Kuala Terengganu, Malaysia

The aim of this study was to compare the relative nutritional benefit of edible Malaysian fishes from the coast of Terengganu in Malaysia, as well as to perform a taxonomical characterization and metal assessment. Discrimination between species was carried out by a morphological and molecular approach by evaluating the total concentrations of metals by ICP-MS analyses and the fatty acids (FA) composition using the GC–MS approach on the fish fillet tissues. The taxonomical studies detected fishes of 11 families and 13 species. The heavy metal assessment showed that all detected elements did not exceed the regulatory limit stated by Malaysian Food Regulations. The proportion of saturated fatty acids (SFA) ranged from 33 to 58.34%, followed by the polyunsaturated fatty acids (PUFA) values from 24 to 51.8%, and the lowest proportion was of monounsaturated fatty acids (MUFA), ranging from 12.7 to 35.9%. The ω-3/ω-6 PUFA and PUFA/SFA ratios were determined in the range 1.1 to 7.4 and 0.35 to 1.6, respectively. The C20:5 ω-3 and C22:6 ω-3 acids were detected at levels comparable to those found in the corresponding species from similar tropical marine ecosystems. The high FA values can be useful biochemical tools for comparing the relative nutritional benefits of these biodiverse and non-toxic edible Malaysian fishes.

HEAVY METALS BIOACCUMULATION AND RISK ESTIMATION IN EDIBLE FRESHWATER FISH FROM PEDROSO RESERVOIR (MAYABEQUE, CUBA)

This work is a validation of the second step of a heavy metal monitoring procedure in Cuba fluvial ecosystems. Concentrations of seven heavy metals were measured by ICP-MS in water samples collected from the Pedroso reservoir (Mayabeque province, Cuba) and its main tributaries, as well as in edible muscle of three locally consumed fish species: Oreochromis spp., Tinca tinca and Clarias gariepinus. The results show a high concentration of Pb in areas near a paint factory (85.5 μg/L), an asphalt factory and a high traffic area (345.8 μg/L). Metal content (in mg/kg ww) in fish fillet ranged as follows: Cr (0.01-0.58), Co (0.01-0.58), Cu (0.23-88.16), Zn (4.9-29.9), As (0.01-0.86), Cd (0.02-2.93) and Pb (0.01-1.23). According to Cuban regulations, concentrations of Cd in muscle are not safe in 37.5 to 44.0 % of the studied fishes, while Pb is high in 14.0 to 20.0 %. Non-carcinogenic risk (HI) is present when daily intake is above 81 g/day. Carcinogenic risk (ELCR) is calculated to be 5.8 × 10–4 according to the US-EPA methodology. Fishermen families are the most sensitive population sector. Local authorities were informed and different measures were taken to avoid polluted fish consumption and the reduction of pollutant sources.

Influence of processing methods on quality and stability of silver catfish (Chrysichthys nigrodigitatus)

The study assessed different processing methods (freezing, smoking, oven drying and boiling) on fillet nutritional quality and stability of silver catfish. All analyses followed standard procedure. Results of proximate composition showed significant increase (p< 0.05) in protein (51.98%), lipid (11.65%), ash (3.82%) and calorie (432.57 Kcal/g) contents in the dried fillets. Thus, these variable increased with increasing processing temperature. On the other hand, moisture and carbohydrate contents decreased with temperature. The stability indices showed significant differences (p < 0.05) in free fatty acid of frozen (0.21%), boiled (0.8%), smoked (2.96%) and dried (9.87%). The lowest calcium (39.7%) was recorded in the frozen sample while the highest level (53.12%) in oven dried. Thiobarbituric acid decreased with increase in processing temperature with the highest level (27.14 mg MDA/100g) observed in the frozen fillet while the least value (2.08 mg MDA/100g) was obtained in the boiled samples. Calcium and phosphorus contents did not show any particular trend. The smoked fish fillet had the highest fibre content of 2.6%. Total volatile base nitrogen was generally low in all treatments. Inference from this study revealed that differently processed Chrysichthys nigrodigitatus was a rich source of fatty acids and essential minerals being very vital to the diet of humans.

The Effect of Different Types of Fish on Physical Characteristic of Fish Meatball

Mince fish can be made into a gel-based product. One of the gel-based products is fish ball. Making fish balls can use economical fish to add value to a product. This study aims to determine the differences in the physical characteristics of fish balls with the use of different types of fishThe treatment in this study is to use different types of fish. The types of fish used were Tilapia (Oreochromis mossambicus) and Mackerel (Restrelliger sp) Other additional ingredients are tapioca flour and seasoning fo making fish ball. The calculating in this study is the yield of fish fillets (skinless) and physical characteristics of product. The results of this study showed that the yield value of tilapia fish fillet is 33, 76% with the number of meatballs produced is 9-13 meatballs. While the yield of mackerel fillet was 49.29% with the number of meatballs produced as many as 24-29 meatballs. The characteristic value of the appearance of the tilapia fish ball is 8 while the mackerel meatball is 7.6. The aroma value of tilapia and mackerel fish balls were 7.4 respectively. Texture value in tilapia fish meatballs is higher than mackerel meatballs, which is 8.2.