Effect of chilled sea water storage of oil sardine (Sardinella longiceps) on quality changes during frozen storage

The shelf-life of frozen oil sardine (Sardinella longiceps) can be improved by preserving the fish immediately after catch in chilled sea water before freezing. Delayed icing caused considerable deterioration in quality and reduced frozen shelf-life. Oil sardine preserved in chilled sea water were found to be suitable for freezing up to 5 days whereas iced samples could be frozen only up to 2 days.

Studies on frozen storage of cuttle fish fillets

The freezing and cold storage characteristics of cuttle fish fillets have been studied. The yield of fillets from cuttle fish was about 35% and the fillet had an average moisture content of 76.85% and fat 0.82% During storage at -20 ± 1°C for 16 months the salt soluble nitrogen of the fillets decreased from 85.1to35.36%, the non-protein nitrogen from 24.61 to 20.84% and alpha amino nitrogen from 252 to 140mg/100g. Initially the fillets were white in colour, showed signs of desiccation by 4 months storage which increased on further storage and the fillets finally became dull white with yellow discolouration inside. The firm and chewy texture of the cooked fillets changed to rubbery even though the product was slightly sweet at the end of that storage period of 16 months.

Studies on freezing and storage of Psenopsis cyanea

The freezing and storage characteristics of Psenopsis cyanea caught on board FORV Sagar Sampada from a depth of 350 m off Cochin are reported. The fat content of the fish was high (15.58% on the weight of whole fish) and the meat was white in colour. Peroxide value, free fatty acids and thiobarbituric acid values increased during frozen storage and organoleptically the fish was acceptable up to 32 weeks at -22 ± 1°C.

Effect of liquid nitrogen freezing and subsequent storage on survival of Staphylococcus aureus and Streptococcus pyogenes in treated prawn meat

Prawn meat treated with Streptococcus pyogenes B-49-2 culture and Staphylococcus aureus ATCC-12598 culture were frozen in conventional plate freezer at -40°C and by spray type liquid nitrogen freezer. The frozen products were stored at -18°C. Streptococcus pyogenes B-49-2 showed low sensitivity to cold injury during freezing and frozen storage. Staphylococcus aureus ATCC-12598 survived during the entire storage period of 240 days. Total bacterial count of untreated prawn meat was found to be always lesser in liquid nitrogen frozen products than that in plate frozen products.

Effect of pre-processing iced storage on deteriorative changes in lipids of silver pomfrets stored at -18°C

Silver pomfret (Pampus argenteus) was frozen in the fresh condition as well as after holding in ice for one, two and four days. Evaluation of changes in the quality of these samples during storage at -18°C has shown that shelf-life decreased sharply if the pre-freezing iced storage was more than one day. The shelf-life of one day iced, two day iced and four day iced frozen samples were 32, 20 and 16 weeks respectively. No correlation was observed between the peroxide value and the organoleptic detection of rancid flavour. Levels of free fatty acids were more in the samples frozen after storage in ice for one day than in all the other samples.

Studies on iced storage of cultured rohu (Labeo rohita)

The biochemical, bacteriological and organoleptic changes in cultured rohu (Labeo rohita) during iced storage have been studied. Non-protein nitrogen decreased and water soluble nitrogen remained almost same during storage in ice. Initially, when the fish was in pre-rigor and rigor conditions, the extractability of protein was low (45 to 50%) which increased after the resolution of the rigor and the decrease in extractability towards the end of storage was insignificant. The total volatile base nitrogen remained steady up to 7 days in ice and showed slight decrease on further storage. During iced storage the bacterial count increased from 10^3/g to 10^5/g by the 11th day of storage. Nearly 80-90% of the total bacterial population in fresh fish was constituted by mesophiles which decreased gradually (decreased to 1% by 13th day of iced storage). Organoleptically the fish was acceptable up to 15 days in ice.

Solid loss and weight gain in prawns during storage in ice

Loss of solids from and gain in weight of meat of whole prawn and prawn meat stored in ice has been studied to explain the mechanism of solid loss. Two stages are identified in this phenomenon. In the first stage water is absorbed without loss of solids resulting in a maximum increase in weight. In the second stage both solids and water are lost resulting in gradual decrease in weight from the maximum reached but not reaching the original weight. It is inferred that whole prawns stored in ice up to two days give the maximum peeled yield without loss of nutrients and at the same time making the peeling process easier.

Bulk packages for storage and transportation of salted and dried fish

The effect of bulk packaging on the storage of salted and dried fish was studied at ambient conditions. Four different packaging systems were tried, among which gusseted type high density polyethylene woven sacks having either circular loom or traditional loom laminated with 100 gauge low density polyethylene were found to be best suited for dry fish packaging as they could withstand the hazards of handling, transportation and storage.

The effect of various salinity levels and stocking density manipulation methods on the survival of milkfish fry (Chanos chanos Forsskal) during storage

Results of the study indicate that the survival rate and increase in body weight did not differ significantly at different salinity levels or at different stocking density manipulation methods. A significant interaction between salinity and stocking density manipulation could not be demonstrated statistically. There apparently is no need to reduce the salinity of the water used in storing milkfish Chanos chanos fry in order to attain higher survival as commonly believed. Sufficient food and maintenance of good water quality are more important than salinity for higher survival of fry during storage.

Effect of preprocessing storage conditions on the carbonyls of oil sardine

Changes in the total as well as major individual carbonyls of oil sardine muscle during storage at room temperature for 24 h and in crushed ice up to 6 days are reported. Carbonyls extracted with hexane were converted to their 2:4 dinitrophenyl hydrazone (DNPH) derivatives and were separated into major classes by column chromatography on celite/magnesia. Individual carbonyls were then identified by capillary gas chromatography of these derivatives. Though absolute values for carbonyls exhibited wide variations depending upon the degree of freshness, the pattern of changes in the carbonyls during storage of fish under different conditions gave an insight into the influence of carbonyls on flavour. The significance of the findings is discussed.

Shelf-life of rotary and solar tunnel dried SIS products under different packaging and storage conditions

A study was conducted on the shelf-life of rotary and solar tunnel dried SIS products under different packaging and storage conditions. Organoleptically dried products were found in good condition after a storage period of 60 days in ambient and chilled conditions. The moisture content, TVB-N value and bacterial load slightly increased during 60 days of storage in ambient and chilled conditions. The changes in moisture content and bacterial load were faster in ambient temperature than in chilled storage condition whereas changes in TVB-N value was higher in chilled condition than in ambient temperature. The initial moisture content was in the range of 13.71% to 22.84%. After 60 days of storage in ambient and chilled condition the moisture content of dried products was in the range of 15.09% to 25.11% and 14.49% to 25.01%, respectively. The initial TVB-N value was in the range of 10.64 to 17.52 mg/100g and after 60 days of storage in ambient and chilled condition, TVB-N value was in the range of 29.00 to 34.82 mg/100g and 31.41 to 39.11 mg/100g, respectively. The initial bacterial load was in the range of 1.91x10 super(8) to 2.84x10 super(8) and after 60 days of storage in ambient and chilled condition, the bacterial load was in the range of 6.2x10 super(8) to 1.8x10 super(9) and 5.75x10 super(7) to 5.05x10 super(8) CFU/g, respectively. The results of the present study indicated that it is necessary to store high quality dried products in sealed packed in chilled condition to ensure good quality up to a certain period of time.

Organoleptic and microbiological quality changes of catla (Catla catla) in immediate and delayed ice storage and at ambient temperature

An investigation was carried out on the quality changes of Catla (Catla calla) stored immediately (0 h) in ice, after 6 hours in ice and at ambient temperature. The samples were examined for organoleptic and microbiological parameters in summer. Organoleptically, the acceptability of fish varied between 16-20 days in both the iced storage conditions and 12-13.5 hours at ambient temperature (28°C). When fish were organoleptically just acceptable on the 16th day of storage, bacterial load were 6.23 and 6.17 log10 cfu/g, respectively for 0 hour and after 6 hours iced fish. But on the 20th day of storage, when fish were just unacceptable SPC were 6.51 and 6.62 log10 cfu/g. In case of ambient temperature storage condition standard plate count was 8.36 log10 cfu/g on 13.5 hours, when fish were organoleptically just unacceptable. At the time of rejection for fish stored in ice (0 hour and after 6 hours) on 20th day, gram negative and gram positive values were 55.45%, 44.55% and 44.52%, 55.48% respectively. While fish were rejected after 13.5 hours at ambient temperature gram negative and gram positive bacteria were found as 43.02% and 56.98%. The differences in SPC, gram positive and gram negative bacteria between the storage times were statistically significant (p<0.05).

Study on shelf life of fish cake prepared from surimi of silver carp (Hypophthalmichthys molitrix) during frozen storage

Surimi was prepared from silver carp with an aim to put this underutilized fish for profitable use. The mince prepared was washed twice with chilled water (5°C) using mince to water ratio (w/v) of 1:2 for 5-6 minutes each. After final dewatering to moisture content to about 80%; half the quantity of washed minced meat was mixed with cryoprotectants (4% sorbitol, 4% sucrose and 0.3% sodium tripolyphosphate) to produce surimi. The prepared surimi and the dewatered minced meat were packed in LDPE bags, frozen using a plate freezer and stored at -20°C. Surimi and dewatered minced meat from frozen storage were used as base material for production of fish cakes. These were fried at 160°C for 3 to 4 minutes before serving for organoleptic test. Changes in salt soluble nitrogen, total volatile base nitrogen, non-protein nitrogen, peroxide value and free fatty acid of surimi and dewatered mince were estimated at every ten days interval during the storage period of 3 months. The study has indicated that frozen storage of surimi could be a potential method for effective utilization of silver carp. This surimi when incorporated in fish cakes yielded products which retained the shelf life even up to 90 days of storage.

Microbiological quality study of Macrobrachium rosenbergii (de Man 1879) during storage at -20°C temperature

The shelf life of fresh water prawn Macrobrachium rosenbergii by applying low temperature was investigated. M. rosenbergii preserved at -20°C was subjected for quality assessment before storage and at 15, 30, 45, and 90 days of storage period. The quality assessments as done microbiological viz. total bacterial count (TBC), total mould count (TMC), total yeast count (TYC), total coliform count (TCC) and salmonella count. All the samples were acceptable during 90 days because the upper limit of all spoilage indicator was not exceeding within the experimental time period.

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.