Chemical properties and changes during storage of some Indian ray liver oils

Ray liver oils are used in leather industry and the yield of oil from fresh good livers ranges from 30-35%. About 4,500 tons of rays are landed annually on the Indian coast. The present note reports the results of investiga_ tions on the constants and storage condition. of ray liver oils as the available data about them are scanty

The bacterial flora, trimethylamine and total volatile nitrogen of fish muscle at 0° c. (in ice).

Observations on the changes occurring in the bacterial flora and the trimethylamine and total volatile nitrogen content of fish muscle at 3° C. were reported previously (Velankar, 1956). The results of similar studies on fish kept in ice storage are presented in this paper and the bacterial flora, isolated during these investigations, is described

Studies on the Indian sardine oil

Sardines along with other Clupeids comprise nearly 20% of the total catch which is roughly one million tons per annum. Among the sardines the oil sardines {Sardinella longiceps) form the most important group along the West Coast and the fishery spreads over October-March. During the heavy seasons the bulk of the catch is utilized for the manufacture of fish oil and fish guano. The correct assessment of the oil production is not possible as it is manufactured by the private merchants all along the coast. A rough estimate is possible from the oil sardine landings. The approximate percentage of the extractable oil from fresh sardines is 5%. The general method which has undergone very little improvement since its inception which dates back as far as forty years (1921) consists in boiling the fish with water in large iron pans over open fire and pressing the boiled mass in coir bags with the aid of vertical screw presses. The liquid is drained into settling tanks which are interconnected at top and bottom for the separation of oil and water. The separated oil is stored in tins or tanks until it is finally exported. The oil so prepared is mostly used for painting boats and for tempering steel. The versatile uses of the fish-body oils and their products have not assumed much importance in India, due to its uncertain quality and the non-availability of the good oil

Experimental preservation of fish in aureomycin ice

Exploratory work carried out in Canada during the last decade on the comparative value of several chemicals and antibiotics in delaying fish spoilage has indicated the possibility of increasing the storage life of iced fish by incorporating trace quantities of antibiotics in the ice (Tarr et al, 1950; Boyd etal, 1953; Gillespie et al, 1955). Among the antibiotics tried so far aureomycin gave most encouraging results, according to the Canadian workers, who employed mainly the bacterial microscopic count for objective evaluation of the quality of fish in storage. These workers reported aureomycin to be effective at levels of 1 to 2 p.p.m. Velankar (1957) who examined the effect of aureomycin on the growth of a number of bacterial species isolated from marine sources, i.e., sea-water, marine mud, plankton, fresh and spoiling sea-fish, found that at the level of 2 p.p.m. aureomycin delayed growth in 40%, while at the level of 5 p.p.m. growth was delayed in the case of 70%, of the bacteria. Work reported from the Torry Research Station, Aberdeen, based on bacteriological, chemical and organoleptic examination of the fish also indicates that a concentration of 5 p.p.m. of aureomycin in the ice is necessary for increasing the storage life significantly (Ingram et al., 1956). The use of different species of fish, and also different criteria for assessing the state of preservation of the fish in storage, in the investigations of the Canadian and British workers probably explain the different findings

Fish curing and fishery by-products

As in the case of many of the maritime countries of the world Fish Curing is one of the oldest industries in India. As much as 21% of the total production is marketed in the form of dried fish and 19% comprising mainly sardine, mackerel, catfish, seer-fish, pomfret, shark, sole, etc., in the form of salted fish

Not Available

Not AvailableRay liver oils are used in leather industry and the yield of oil from fresh good livers ranges from 30-35%. About 4,500 tons of rays are landed annually on the Indian coast. The present note reports the results of investiga_ tions on the constants and storage condition. of ray liver oils as the available data about them are scanty.Not Availabl

Not Available

Not AvailableSardines along with other Clupeids comprise nearly 20% of the total catch which is roughly one million tons per annum. Among the sardines the oil sardines (Sardinella longiceps) form the most important group along the West Coast and the fishery spreads over October-March. During the heavy seasons the bulk of the catch is utilized for the manufacture of fish oil and fish guano. The correct assessment of the oil production is not possible as it is manufactured by the private merchants all along the coast. A rough estimate is possible from the oil sardine landings. The approximate percentage of the extractable oil from fresh sardines is 5%. The general method which has undergone very little improvement since its inception which dates back as far as forty years (1921) consists in boiling the fish with water in large iron pans over open fire and pressing the boiled mass in coir bags with the aid of vertical screw presses. The liquid is drained into settling tanks which are interconnected at top and bottom for the separation of oil and water. The separated oil is stored in tins or tanks until it is finally exported. The oil so prepared is mostly used for painting boats and for tempering steel. The versatile uses of the fish-body oils and their products have not assumed much importance in India, due to its uncertain quality and the non-availability of the good oil.Not Availabl

Shark spoilage bacteria

While the bacterial flora associated with spoilage' of teleosts has been extensively studied, elasmobranch spoilage flora has received little attention. Wood who investigated the bacteriology of shark spoilage, found the spoilage flora differing significantly from that of teleosts. He found that in the sharks there was no succession in the bacterial genera during spoilage

Not Available

Not AvailableObservations on the changes occurring in the bacterial flora and the trimethylamine and total volatile nitrogen content of fish muscle at 3° C. were reported previously (Velankar, 1956). The results of similar studies on fish kept in ice storage are presented in this paper and the bacterial flora, isolated during these investigations, is described.Not Availabl

Not Available

Not AvailableExploratory work carried out in Canada during the last decade on the comparative value of several chemicals and antibiotics in delaying fish spoilage has indicated the possibility of increasing the storage life of iced fish by incorporating trace quantities of antibiotics in the ice (Tarr et al, 1950; Boyd etal, 1953; Gillespie et al, 1955). Among the antibiotics tried so far aureomycin gave most encouraging results, according to the Canadian workers, who employed mainly the bacterial microscopic count for objective evaluation of the quality of fish in storage. These workers reported aureomycin to be effective at levels of 1 to 2 p.p.m. Velankar (1957) who examined the effect of aureomycin on the growth of a number of bacterial species isolated from marine sources, i.e., sea-water, marine mud, plankton, fresh and spoiling sea-fish, found that at the level of 2 p.p.m. aureomycin delayed growth in 40%, while at the level of 5 p.p.m. growth was delayed in the case of 70%, of the bacteria. Work reported from the Torry Research Station, Aberdeen, based on bacteriological, chemical and organoleptic examination of the fish also indicates that a concentration of 5 p.p.m. of aureomycin in the ice is necessary for increasing the storage life significantly (Ingram et al., 1956). The use of different species of fish, and also different criteria for assessing the state of preservation of the fish in storage, in the investigations of the Canadian and British workers probably explain the different findings.Not Availabl