Fatty acid composition of red drum maintained by fishmeal, fish oil substitutes in diets

Recent research by the authors evaluated strategies to reduce fishmeal and fish oil in diets for red drum by substituting terrestrial proteins and lipids while maintaining beneficial fatty acids with DHA supplements derived from marine algae. Results suggested fatty acid-enriched finishing diets can be used with growout diets containing little or no fishmeal and fish oil to achieve the desired DHA content in the final fish fillets.

Effect of aureomycin on the behaviour of certain free amino acids in oil sardine (Sardinella longiceps) held in ice storage

The course of development of a few free amino acids under the influence of aureomycin in oil sardine (Sardinella lingiceps) held in ice storage was investigated. The levels of leucines and valine regularly increased in the control and aureomycin treated fush throughout the storage period. Alanines and threonine showed similar trend in both control and fish treated with 20ppm aureomycin. These amino acids however showed a gradual fall in fish treated at 5 ppm level. The changes in tyrosine+tryptophane were found to be irregular. Most of the amino acids studied indicated a remarkable change in trend by about the 16th day of ice storage in the case of fish treated with 50ppm aureimycin.

Studies on fish lipids. Pt. 2. Fatty acid composition of lipids of oil sardine (Sardinella longiceps)

Gas-liquid chromatography has been employed for the qualitative and quantitative analysis of the component fatty acids in lipids of oil sardine (Sardinella longiceps). Phospholipids and triglycerides of the lipids were previously separated by column chromatography before they were converted into the methyl esters of the fatty acids. The predominant acids present in the depot fat of the fish have been found to be C14:0=8.13%, C16:0=27.9%, C18:0=3.8%, C18:1=15.4%., C20:5=10.6% and C22:6=8.8%. Apart from the above acids the distribution of minor acids belonging to Cl8, C20 and C22 groups have also been worked out. The separated phospholipid fraction contained more than 70% polyunsaturated acids of which the important constituents were docosahexaenoic (C22:6=28%) and eicosapentaenoic (C20:5=10.6%). A marked reduction was found in the amounts of polyunsaturated acids in triglycerides, their total amount registering about 20%. This fraction recorded about 48% of C16 acids of which palmitic and palmitoleic acids amounted to 25.8% and 19.1% respectively. Occurrence of odd numbered fatty acids C15 and C17 has also been noted in the phospholipid and composite samples of the fish.

Use of different glazes in frozen oil sardines

This paper reports on the relationship between the seasonal variations in the oil content of the Indian oil sardines (Sardinella longiceps) and their frozen storage life at -l8°C and on the use of various chemicals and coating materials to extent their storage life. It is observed that there is an inverse relationship between the oil content and the frozen storage life- oil content varying from 10.33 to 42.43% (MFB) and storage life from 2 to 5 months. Extension of storage life is achieved by dipping in hydroquinone solution prior to freezing or by coating with agar after freezing. Data on changes in peroxide value, free fatty acids, moisture, drip and organoleptic characteristics during frozen storage are presented.

On the canning of Sardinella fimbriata Sardinella gibbosa and Sardinella sirm in oil pack

This note gives details of experiments conducted on the canning of certain species of sardines viz. Sardinella fimbriata, Sardinella gibbosa and Sardinella sirm which are landed in commercial quantities in the East Coast of Madras State and which have not so far been tried for canning. The experiments conclusively prove that these species of sardines can also be canned in oil pack and good canned products manufactured out of them.

Studies on shark liver oil and its residue

Seasonal variation in oil and moisture contents and vitamin A potency of oil in livers from different species of sharks landed at Veraval coast were studied. Values of moisture, protein, ash and vitamins in defatted liver residue were determined.

Preliminary observations on changes in nucleotides in oil sardine and certain Penaeid prawns during chill storage

Preliminary study has been made of the changes in common 5' nucleotides in oil sardine (Sardinella longiceps) and two Penaeid prawns of Indian waters during chill storage. The course of nucleotide degradation has been followed in the fresh fish and shell fish during ice storage. The level of inosine monophosphate (IMP) in prawns showed significant but steady decrease during ice storage and this appears to serve as useful indication of length of storage. Comparison has been made on the pattern of nucleotide changes in block frozen fish and individually quick frozen fish stored at -23°C.

An effective method for reducing belly-bursting in frozen oil sardines

A dip treatment in 15% sodium chloride solution for 30 minutes prior to freezing was found to be effective in reducing belly-bursting occurring during freezing and thawing of oil sardines. The effect of size and fat content of sardines on belly-bursting phenomenon and storage characteristics of brine treated sardines have been studied.

Digestible protein and energy value of fish meal, dextrin, fish oil and soybean oil for Thai sharpunti (Puntius gonionotus Bleeker)

A laboratory trial was conducted to determine the digestible protein and energy value of fish meal, dextrin, fish oil and soybean oil for Thai sharpunti (Puntius gonionotus Bleeker). A reference diet containing 35% protein was formulated in which fish meal was the sole source of protein. Five test diets were formulated using reference diet and individual test ingredients (fish meal, dextrin, fish oil and soybean oil). Each treatment had three replicates with 15 fish per replicate. Fish were fed twice daily at the rate of 5% of their body weight. The result of the study indicated that the dietary protein in both reference and test diets were well digested and the apparent protein digestibility (APD) values of test diets ranged between 82.81 and 85.99%. The APD value of fish meal protein was 88.05%. The apparent digestible energy (ADE) value for the test ingredients ranged between 70.79 and 85.80% with soybean oil having the highest and fish meal the lowest value. The ADE values calculated in terms of Kcal/g of ingredients were 3.68, 3.22, 4.38 and 4.44 Kcal/g for fish meal, dextrin, fish oil and soybean oil respectively.