Storage studies on prawns dried in rotary drum dryer

Storage study carried out with prawns processed in rotary drum dryer showed that the deteriorative changes taking place are mostly due to the presence of air and oxygen. By storing under inert atmosphere of nitrogen or carbon dioxide the original characteristics can be maintained over a considerable length of time.

Studies on cannning of mackerel fillets in oil

Canning operations suitable for packing mackerel (Rastrelliger kanagurta) in the form of skinless and boneless fillets in oil were studied and the process standardised. The technique of lye peeling for skin removal could be successfully applied. The storage life of the final product was tested over a period of one year and found to be quite comparable to other similar fish products.

Beverage preparation from fish hydrolysate

A method for the preparation of energy food incorporating fish hydrolysates, sugar, cocoa, malt extract etc. is described. The product has good consumer appeal. The preparation does not impart any bitter taste of the hydrolysate to the final product irrespective of the type of fish used for preparing the hydrolysate. It freely mixes with hot or cold milk and the resulting drink is adjudged to be very palatable.

Studies on maturation, spawning, fecundity and sex ratio in Barbus (Puntius) sarana (Hamilton-Buchanan) from Lake Kolleru, Andhra Pradesh

Barbus sarana contains only one batch of mature ova in the mature ovaries to be spawned in one spawning act. It spawns during July-September. The fecundity ranges from 11,201 to 224,248 ova. There is a positive curvilinear correlation between total length and fecundity, the latter increasing with length at a rate of less than cube of length. The stock of this species from Lake Kolleru appears to be more fecund than that inhabiting Loni reservoir. The sex ratio indicates that females outnumber males in all months and in larger length groups. Females appear to reach a larger length than males.

Studies on Colombo-curing of mackerel (Rastrelliger kanagurta)

Results of investigations carried out to improve the process of 'Colombo-curing' of mackerel are presented in this paper. Optimum composition of salt and gorujka puli (malabar tamarind, Garcinia cambogea) to be used in the pickle mixture to give a product of good organoleptic and chemical characteristics have been worked out. Sodium benzoate is used as a preservative against the attack of molds, 'red' etc.

The free alpha amino acid nitrogen contents of some common food fishes of Kakinada region, Andhra Pradesh

The moisture and free alpha amino nitrogen contents of some important food fishes and shell fishes of Kakinada region have been studied. Crustaceans and molluscs contain free alpha amino acids in quantities several times higher than all other aquatic animals examined in this study. Their probable role in the physiological activities of these animals has been discussed.

Pickle curing of fish using tartaric acid and garlic as preservatives

Tartaric acid and garlic have proved highly satisfactory as pickling agents when used in combination, giving fishery products of good appearance, texture, taste and shelf life. Full details of the pickling method are given.

Commercial studies on radiation preservation of fish and shell-fish in Canada

The author describes work being undertaken at the Fisheries Research Board of Canada's Laboratory at Halifax (Nova Scotia). These studies relate particularly to the irradiation of fish and shellfish for storage, and bacterial analysis of irradiated products.

Reliability and need for standardisation of electrical systems in small wooden fishing vessels

The working condition and atmosphere in a wooden fishing vessel are generally most injurious to the electrical systems. Therefore great care has to be taken in designing electrical systems for small c1afts. This paper deals with the difficult operating conditions and standardisation of electrical systems as applicable to small fishing vessels.

Effect of box stowage on quality fish

Quality of boxed cod and haddock was compared with that of penned fish in terms of organoleptic grading, trimethylamine values, Intelectron Fish Tester readings and fish and fillet yield. Boxed fish showed a higher percentage of grade one fish than penned fish. TMA values, however, did not differ greatly. There was less physical damage due to squeezing with boxed fish and consequently a greater yield of landed round fish and fillets.

Serological studies on oil sardine (Sardinella longiceps) and mackerel (Rastrelliger kanagurta)

An antiserum was raised in a rabbit against 0 panel red cells of mackerel. The erythrocytes of oil sardine and mackerel were tested against human blood typing sera anti A and B and also the test serum of rabbit which revealed the presence of antigens A and B. In addition, an antigen common to both the fishes and human A, B and 0 panel red cells was noted but not identifiable. The blood group B did not manifest itself clearly either in oil sardine or mackerel. The blood groups A, AB and 0 indicated the existence of genetically different groups of oil sardine and mackerel. Isoagglutinin tests revealed the presence of a reciprocal relationship with antigens A and B in both these fishes.

Electrophoretic characteristics of oil sardine (Sardinella longiceps) and mackerel (Rastrelliger kanagurta) eye lens proteins

Electrophoresis of eye lens proteins of oil sardine and mackerel showed separation of proteins into three and four components, indicating the heterogeneous nature of the population.

Electrophoretic studies on serum proteins of oil sardine (Sardinella longiceps) and mackerel (Rastrelliger kanagurta)

Oil sardine blood tests against human typing sera indicated A-positive, A-negative and B-negative. The blood of mackerel is antigenically negative both for A and B. Electrophoretic studies on serum proteins revealed the existence of genetica1ly different groups of oil sardine and mackerel on the south-west coast of India.

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.

Reaction of fishes to the underwater A.C. field

A comparative study on the effect of A.C. field on Puntius ticto, Heteropneustis fossilis and Tilapta mossambica was carried out using a slowly rising field intensity. Well defined reactions appeared in the species of fish with slight specific variations, depending on their orientation in the electrical field, on reaching the field intensity to specific value. These reactions can be distinguished as first reaction, when the fish perceive the surrounding field, jerky swimming when parallel to the current lines (longitudinal oscillotaxis), the static position finally adopted by the fish sooner or latter depending on the potential gradient (transverse oscillotaxis), and a state of muscular rigidity (tetanus). After switching off the current, a hypnotic condition prevailed in the treated fishes before returning to their normal swimming condition. The orientation of fish body in the field had an important bearing on the behaviour reactions and current thresholds necessary for those reactions. Initial reaction, jerky swimming between electrodes and hypnosis after stoppage of current appeared in fishes earlier when the fish body was in parallel to the current lines, whereas fishes responded to transverse oscillotaxis quickly when perpendicular to current lines.