Development and storage characteristics of dehydrated salt mince from low priced fish

The study showed that less initial moisture with high salt content will be the best condition for enhanced storage life of dehydrated salt mince. Between sample I (10% salt per meat weight) and sample II (15% salt per meat weight) the latter was comparatively better in colour, odour and longer shelf-life. At room temperature the dehydrated salt mince has not showed any increase in total bacterial count. It is also found that the storage life of the salt mince can be enhanced to a significant extent by lowering the moisture content to below 10% and increasing the salt content to above 30%. Peroxide value, free fatty acid value, total volatile nitrogen and trimethylamine registered gradual increase during storage at room temperature for all the three samples. Among the three samples, the sample treated with 0.1% citric acid and 0.125% butylated hydroxy anisole was comparatively better in appearance and showed less rancidity as indicated by TBA values, up to a period of 15 weeks and thereafter all the three samples were almost similar in storage characteristics. Hence, the treatment with citric acid and B.H.A. has apparently not much significance in improving shelf-life and quality of salted dehydrated fish mince.

Effect of mixed feeding schedule on growth and nutrient utilisation in Rohu, Labeo rohita (Ham.) fingerlings

Studies on nutrient utilisation and growth of rohu (Labeo rohita) fingerlings (3.13-4.09 g) raised on seven feeding schedules under laboratory conditions (26.3-33.5°C) showed that two days regular feeding on Diet B (high protein, 38.90%) resulted in maximum growth and protein retention efficiency. While regular feeding on low protein diet (Diet A) resulted in poor nutrient utilisation and growth of fish, high protein diet (Diet B) did not show any significant difference in growth from the mixed 2A-3B schedules but exhibited comparatively low protein retention efficiency. The other feeding schedules were 1A-2B, 1A-3B, 2A-2B and 2A-4B, where the numerical value refers to the number of days for continuous feeding of a particular diet. The diets A and B served as the controls which contained 3.40 and 3.67 kcal/g gross energy respectively. The 2A-3B feeding schedule was also found to be highly economic as an expenditure of Rs.11/- only was required for raising the body weight by one kilo as against Rs.17/- with high protein diet (Diet B) as calculated

Effect of feed quality restriction followed by realimentation on growth, nutrient utilization, biochemical changes and haematological profiles of Indian major carp, rohu (Labeo rohita H.)

To investigate the effect of protein restriction with subsequent re-alimentation on nutrient utilization, hematological and biochemical changes of Indian major carp, Rohu (Labeo rohita H.), 150 acclimatized Rohu fingerlings (average 20.74 ± 0.13 g) divided into five experimental groups (30 fingerlings in each groups with three replications with 10 fingerlings in each) for experimental trial of 90 days using completely randomized design. Control group (T sub(CPR)) was fed with feed having 30% crude protein at 3% of body weight for 90 days trial period. Other experimental groups T sub(1PR) was alternatively 3 days fed with feed having 20% CP and 30% CP at 3% of body weight, T sub(2PR) was alternatively 7 days fed with feed having 20% CP and 30% CP at 3% of body weight, T sub(3PR) was alternatively 15 days fed with feed having 20% CP and 30% CP at 3% of body weight and T sub(4PR) was alternatively 25 days fed with feed having 20% CP and 30% CP at 3% of body weight during 90 days trial period with daily ration in two equal halves at morning and afternoon. It was noticed that retention of different nutrients was almost similar among all treatment groups indicated improvement of digestibility of nutrients might not be the mechanisms for recovery growth in carps. Increased percent feed intake of body weight (hyperphagia) (4.14 ± 0.30 or 4.94 ± 0.46 and 3.33 ± 0.29), improved specific growth rate (1.86 ± 0.09 or 2.26 ± 0.05 and 1.43 ± 0.01), absolute growth rate (1.57 ± 0.08 or 1.84 ± 0.18 and 1.36 ± 0.12), protein efficiency ratio (1.19 ± 0.11 or1.16 ± 0.12 and 1.05 ± 0.09) were the important mechanism showing better performance index (21.60 ± 1.09 or 23.80 ± 0.21 and 19.45 ± 0.37) through which the experimental groups which were protein restricted and re-alimented at 3 or 7 days alternatively during 90 days trial period could able to compensate the growth retardation and to catch up the final body weight of control (128.68 ± 11.53 g/f) but other experimental groups failed to compensate during 90 days trial period. Result of the present study indicated that deprived fish i.e., fish received alternate 3 or 7 days protein restriction and re-alimentation showed recovery growth had still lower values of Hb (10.21 ± 0.02, and 9.88 ± 0.04 g/dl), hematocrit value (30.62 ± 0.05 and 26.64 ± 0.11%), total erythrocytic count (3.40 ± 0.01 and 3.29 ± 0.01 X10super(6) mm³), plasma glucose (126.93 ± 0.20 and 126.67 ± 0.05 mg/dl), total plasma lipid (1.04 ± 0.01 and 1.02 ± 0.01 g/dl) and liver glycogen (290.10 ± 0.80 and 288.99 ± 0.95 mg/kg) in comparison to control (10.56 ± 0.08 g/dl, 31.68 ± 0.24%, 3.52 ± 0.03 X10super(6) mm³, 128.23 ± 0.25 mg/dl, 1.07 ± 0.01g/dl and 292.00 ± 0.23 mg/kg) at the end of 90 days trial but total plasma protein in deprived group was compensated with advancement of trial period. All hematological and biochemical parameters studied were proportionately lowered in the experimental group got higher degree of deprivation. These findings suggested that with the increase of trial length complete compensation of hematological and biochemical profiles of rohu might be achieved. The results indicated that the implementation of alternative 7 days low and high protein diet feeding during aquaculture of carps could make economize the operation through minimizing the feed input cost.

High temperature salting of fish mince

Freshly caught miscellaneous fish were transported to the laboratory, gutted and washed before mechanical separation into bone and mince. Seven batches of the mince were then treated with seven different concentrations (Wt/Wt) of sodium chloride before cooking. The cooked mince was divided into two groups, pressed and unpressed. Percentage residual salt of the salted cooked mince, cooked water and salted pressed mince was determined. Also, the moisture content of the salted cooked mince and salted pressed cake was determined

The brine and gas content of sea ice with attention to low salinities and high temperatures

Based on the well known sea ice phase diagram, equations are derived for determining the brine and gas content of sea Ice for high temperatures (range 0 to -2 °C) and low salinities. The presently widely used equations of Cox and Weeks (1982) are valid only for temperatures below -2°C. Fresh-water ice is used as a boundary condition for the equations. The relative salt concentrations in brine are_assumed to be the same as in normal (or standard) seawater. Two sets of equations are presented: 1) accurate formulae based on UNESCO standard sea water equations, and 2) approximate formulae based on general properties of weak solutions. The approximate formulae are not essentially different from the classical system which basically assumes the freezing point to be a linear function of fractional salt content. The agreement between the two approaches is excellent and the approximate system is good enough for most applications.

Evaluation of biochemical characteristics of a traditional salt fermented fish product of northeast India with special reference to its flavour components

'Lona ilish', is a traditional salt fermented fish product, widely consumed and very popular in north-east part of India and Bangladesh. It is prepared exclusively from a high fat fish, Hilsa (Tenualosa) ilisha. 'Lona ilish' was prepared in the laboratory following traditional process. After 150 days of fermentation, a better quality 'lona ilish' was obtained. Biochemical characteristics of market sample was estimated and compared with the laboratory prepared one. A variation in biochemical composition was observed. Sensory quality of the final product of laboratory prepared 'lona ilish' was compared with the market sample and found that the laboratory prepared product scored better than the market sample. The moisture (49.89%) and salt (15.48%) of the final product was found to be satisfactory for stability of the 'lona ilish' at ambient temperature. Analysis of volatile compounds of 'lona ilish' was done using GC-MS. It was concluded that, aldehydes, ketones and esters may possibly contribute characteristic aromas to the overall flavour of the salt fermented hilsa.

High temperature processing of fish sausage 2. - Effect of certain preservatives on the shelf life

The effects of preservatives like fat coated sorbic acid (FCSA) and glucono-deltalactone (D-lactone), both separately and in combination, on the shelf life of high temperature (115.6°C for 20 min) processed fish sausage, stored at three different temperatures namely, ambient (28±2° C), cooler storage (2±2°C) and refrigerator (10±2° C) were studied. Whereas the control (without preservative), FCSA, D-lactone and FCSA + D-lactone treated samples could be stored for 9, 11 and 13 days respectively at ambient temperature, those stored at lower temperatures were found to be in acceptable condition for 70 and 80 days respectively. Organoleptic evaluation of taste, flavour the products carried out by panelists revealed that FCSA and FCSA + D-lactone treated samples were unacceptable with regard to the taste, flavour and texture. However, the taste flavour and texture of the control and D-lactone treated samples were in acceptable condition.

High temperature processing of fish sausage 3. - Studies on some of the storage characteristics

The proximate composition of the high temperature processed fish sausage was found to be 14.56% protein, 4.65% fat, 69.14% moisture, 2.12% ash and 8.12% carbohydrate. The quality of the product during storage was assessed on the basis of the changes observed in the physical, chemical and microbiological parameters. The results of the different tests such as pH, volatile base nitrogen (VBN), trimethyl amine nitrogen (TMA-N) and jelly strength are summarized and discussed. The total bacterial load increased gradually during storage but was not proportional to the initial load.