Studies on packaging of fresh fish

Studies conducted in the laboratory and field have shown that iced fish can be preserved for longer periods in fresh and edible condition in conventional bamboo baskets by providing additional insulated linings of double layer of gunny and polythene or bitumen coated kraft paper. The quality of fish is adjudged by chemical and organoleptic evaluations.

Studies on the preparation of fish protein concentrate

The paper deals with the method of preparation of an edible fish protein concentrate from cheap miscellaneous fish. The method consists in cooking the fish with 0.5% glacial acetic acid, and extracting batch—wise, using ethyl alcohol followed by an azeotropic mixture of hexane and alcohol (B. Pt. 58-68°C). The product is finally vacuum dried during which the residual solvent is also removed. The concentrate prepared by this method contains 85% protein of which 96% is pepsin digestible. The product is practically odorless and almost white in color.

Protein from blanch liquor

A process is described for isolation of edible protein from blanch liquor, which is discarded as a waste at present from prawn canning factories. The protein isolated is colourless and odourless and contains an appreciable amount of salt from the brine used for blanching prawns. It is comparable to fish protein concentrate in amino acid composition.

Partial survey and critique of Ceylon's marine fisheries, 1953-55

This is a resume of a 1953-1955 study of Ceylon's fishing gears, fisheries and records of experimental and commercial fishing operations. Representative catches of edible fish per unit of effort for several of the gears studied are summarized in the table. They are low compared with many countries, indicating low abundance of fish.

The history and fishery potential of Kisoro Minor Lakes part two: Preliminary survey of Lakes Mutanda and Mulehe fisheries 

The fisheries of Lakes Mutanda and Mulehe during 1998/9 were mainly at subsistence scale and only few fishers operated at irregular intervals. The commercial catch records between 1963 to 1999 showed that Lake Mulehe was landing more fish than Lake Mutanda despite the fact that Lake Mutanda (26.4 km2) was bigger than Lake Mulehe (4.11 cm2). The constant decline of catches was due to irregular restocking and applying low stocking densities of fry. However, restocking should consider using species that withstand low temperature (15-240C) in the district. These include Oreochromis niloticus (Nile tilapia), Macropterus salmoides (Black bass), and Cyprinus carpio (Common carp). Most of these species have either disappeared or declined to very low levels. Due to lack of commercial fish species for harvest, the fishers by 1998/9 resorted to harvesting the haplochromines, Clarias carsoni and edible frogs (Xenopus kigesiensis) as alternative resources. Experimental studies have shown the need and techniques to enhance fish production on these two lakes.

Nutritive value of the crab Podophthalmus vigil (Fabricius)

Among the edible crabs, Podophthalmus vigil occupies a distinct position in Porto Novo coast. Though the fishery is seasonal, P. vigil supports an additional crab fishery from august to october. An attempt has been made to evaluate the nutritional status of different size groups of P. vigil. It has been observed that protein and moisture values are more in smaller crabs, corresponding with a drop in carbohydrate and fat. In bigger size groups, the values of fat and carbohydrate are found to be higher, while protein and moisture contents decreased slightly. The total meat content varies in different crabs of the same size group and the average value of the total consumable part is found to be only less than 30% of the total weight of the animal.

Nutritional evaluation of an indigenous low cost protein food

A study of supplementary feeding was conducted on children with a protein food (edible fish powder in the form of 'chutney') for 35 days and the effect assessed periodically. The most noticeable effect was gain in weight and mid arm circumference in children. 35% children showed a weight gain of 1 kg, 27% 0.5 kg, 21% 1.5 kg and 2.5% 2.5 kg. 48% children registered an increase in their mid-arm circumference by 0.5 cm, 16% 1 cm and 2.5% 1.5 cm. 10% children did not gain weight. However, these children had intercurrent infections like measles, whooping cough and asthma.

Freeze drying of fishery products: Part IV - Biochemical changes occurring in prawn muscle during freezing, freeze drying and prolonged storage of the freeze dried product

The changes occurring in water and salt extractable protein and non-protein fractions in prawn muscle of different species during freezing, freeze drying and subsequent prolonged storage have been studied. There is no denaturation of water extractable proteins, whereas salt extractable proteins were rendered insoluble to the extent of 21% due to freeze drying. The freeze dried products remained in good edible condition for 32 months of storage up to which storage characteristics were followed.

Distribution of heavy metals in the northern shrimp Pandalus borealis from the Oslofjord

Studies on the distribution of heavy metals like copper, cadmium, zinc, lead and mercury in deep sea prawns Pandalus borealis in the Oslofjord region showed that those collected from inner and middle fjord contained higher levels of heavy metals than those from the outer fjord. Their content in the edible portions, viz., tail muscle, was less compared to other organs. In terms of metal concentration copper and zinc are present in significant quantities in Pandalus borealis.

Proximate composition of five species of flat fishes

Five species of flat fishes, namely Cynoglossus semifaciatus, C. lida, C. bilineatus, C. macrolepidotus and Psettodes erumei caught in trawlers off Mangalore were analysed for proximate composition of different body parts. These data are discussed in terms of their variability and applications. In whole body of C. lida and C. semifaciatus mean values for moisture, protein, fat and ash content on dry basis respectively were 75.9%, 75.3%, 7.1%, 16.1% and 78.9%, 75.6%. 7.9% and 16.6%. Mean values of these constituents of edible parts in the same order for C. semifaciatus and Psettodes erumei were 77.3%, 80.7%, 7.8%, 10.8% and 77.4%, 86.2%, 3.5% and 11.1% respectively.

Studies on two unexploited fish species: Peristedion adeni and Peristedion weberi

The chemical composition and nutritional quality of Peristedion adeni and Peristedion weberi, two unexploited fish species available in abundance in the Exclusive Economic Zone of India are reported. Size of the fish is small and separation of edible meat is difficult. Best method of utilization of the fish is conversion into meal. Meals having crude protein content varying from 55.0 to 57.0%, ash content from 17.0 to 19.6% and fat content from 17.7 to 18.1% can be prepared from the two species of fish. PER values of the meals are lower than that of casein. Amino acid analysis showed that isoleucine, leucine and valine are not present in the meals in adequate quantities compared to the FAO/WHO (1973) prescribed pattern.

Application of whey protein incorporation with Cinnamon oil as a preservative in Huse huso fillet under chilled storage condition

Biodegradable protein-based film was developed by incorporating cinnamon essential oil (CEO) into whey protein concentrate (WPC) at level of 0.8% and 1.5% v/v. Then physical and mechanical properties of the films were evaluated. Adding CEO to the WPC matrix decreased the water vapour permeability of the films and water solubility. Films containing CEO showed significant antibacterial activity both gram-positive and gram-negative strains and exhibited significant inhibitory effect on the studied fungi. In continue, the effect of whey coating and whey coating incorporated with 1.5% CEO on quality and shelf life of Huso huso fillet during refregrated (4±1°C) storage period were also investigated. The control and treated fish samples were analyzed for microbiological (total viable count, psychrophilic counts), chemical (PV, TBA, FFA, pH, TVB-N), and sensory characteristics in 4-day intervals up of microbial, chmical and sensoy analyses indicated lower levels of PV, TBA, FFA, pH, TVB-N in coasted sampels and specially, those with CEO while were kept in refrigerator. Based on results, whey protein edible coating contain 1.5% cinnamon essential oil could enhance preserving ability Huso huso during storage cold.

Mercury bioaccumulation in pike (Esox lucius) food chain from Anzali Lagoon, Iran

A number of wide-ranging monitoring studies have been performed in order to estimate the degree of mercury (Hg) contamination in freshwater ecosystems. Knowledge regarding contamination of different levels of the food chain is necessary for estimation of total pollutant input fluxes and subsequent partitioning among different phases in the aquatic system. The growing international concern about this environmental data is closely related to the strongly developing ecological risk assessment activities. In addition,freshwater monitoring outputs hold a key position in the estimation of the Hg dose consumed by the human population as it is highly dependent on fish consumption. So monitoring of Hg in the tissue of edible fish is extremely important because of contaminated fish has caused serious neurological damage to new born babies and adults. Mercury tends to accumulate in fish tissue, particularly, in the form of methyl mercury, which is about 10 times more toxic than inorganic mercury. The Anzali lagoon is one of the biggest wetland of Guilan province, which joins to the Caspian sea. Many Chemical and industrial factories plus agricultural runoffs and urban and rural sewages are major polluting sources of the Anzali wetland. Since many of those polluting sources drain their wastes directly or indirectly into the Anzali wetland and their sewages may be polluted with Hg, this study was conducted to find out the bioaccumulation of Hg bioaccumulation in pike (Esox lucius) food chain from Anzali lagoon, Iran. Sampling were carried out from July 2004 to July 2005, in addition 318 speciments of 9 fish species were collected. T-Hg was measured by LECO AMA 254 Advanced Mercury Analyzer (USA) according to ASTM standard No D-6722. Each sample was analyzed 3 times. Accuracy of T-Hg analysis was checked by running three samples of Standard Reference Materials; SRM 1633b, SRM 2711 & Sra 2709. Detection limit was 0.001 mg/kg in dry weight. The Accuracy degree of analyzor equipment with RSD<%0.05 (N=7) was between %95.5 and %105. In overal eigth fish species were distingushed in the gut content of 87 speciments of pike with age 1-5 year and maximum length 550mm. The max. and min. concentration of T-Hg in dorsal muscle of pjke was 0.2ppm in one year and 1.2ppm in five year class. The mean of T-Hg significantly increased with age and length increased (P<0.05).Mercury accumulation pattern in pike was as well as muscle > liver > spleen (P<0.05). THg content in female was higher than male(P<0.05). In contrast the mean of THg concentration in dorsal muscle of eigth fish species as prey was 0.282, 0.261, 0.328, 0.254, 0.256, 0.286, 0.322 and 0.241 ppm for Carassius auratus gibelio, Hemiculter leucisculus, Blicca bjoerkna transcaucasica, Chalcalburnus mossulensis, Rhodeus sericeus amarus, Gambusia holbrooki, Alburnus charusini hohenackeri & Scardinius Erythrophthalmus respectively.Liner regresion indicated that high degree of relationship between age of pike and Uptak/Intake ratio (R2=%99.12) and indicated that the mercury bioaccumulation in the pike dorsal muscle increased with age increased. BFA was >1 and and indicating the mercury biomagnification in the pike food chain. Trophy level of pike in the Anzali lagoon was estimated as well as 3.5 and 4 . It is generally agreed that Hg concentration in carnivorous fish are higher than in noncarnivorous species.

The preservation of some East African freshwater fish

Quality changes during storage were investigated for several commercially important East African freshwater fish. Lates, Bagrus, Protopterus, Tilapia esculenta and T. nilotica were examined during storage in ice and at ambient temperature (250•C). After 24 hours at ambient temperature Lates and Bagrus were completely spoilt but Protopterus was still edible. In iced storage most fish were acceptable for at least 20 days. Organoleptic examination showed that T. nilotica was acceptable after 22 days storage in ice and that gutting was only marginally beneficial. Changes in physical appearance, which could form the basis of a fish inspection system, were recorded during storage. Possible chemical quality control indices were also investigated. It was found that total volatile bases and hypoxanthine are unlikely to be useful quality indices for the species studied with the possible exception of Lates. The bacterial counts of the flesh and skin of T. esculenta and T. niloticus were found to be low (a maximum of 10 organisms per sq cm of skin or per g of flesh) after 22 days storage in ice.

Cytochemical changes in the developmental process of Nostoc sphaeroides (cyanobacterium)

There are several apparent developmental stages in the life cycle of Nostoc sphaeroides Kutzing, an edible cyanobacterium found mainly in paddy fields in central China. The cytochemical changes in developmental stages such as hormogonia, aseriate stage, filamentous stage and colony in N. sphaeroides were examined using fluorescent staining and colorimetric methods. The staining of acidic and sulfated polysaccharides increased with development when hormogonia were used as the starting point. Acidic polysaccharides (AP) were most abundant at the aseriate stage and then decreased, while the sulfated polysaccharides (SP) were highest at the colony stage. Quantitatively, along the developmental process from hormogonia to colony, total carbohydrates first increased, then became stable, and then reached their highest level at the colony stage, while reducing sugars were highest at the hormogonia stage and then decreased sharply once development began. SP were not detectable in the hot water soluble polysaccharides (HWSP), and hormogonia had the lowest content of AP, while old colonies had the highest. The AP content of the aseriate stage, filamentous stage and young colony stage were very similar. The evolutionary relationships reflected in the developmental stages of N. sphaeroides are discussed.