Pickled products from green mussel

Methods of preparing different types of delicious ready to serve pickled products from green mussel (Perna viridis) and a comparative study of their storage characteristics are reported. Of the three types of products, namely, dried and pickled, fried and pickled and light smoked and pickled, the last one had the best shelf life. The optimum conditions of drying and smoking for preparing such type of pickles are also reported.

Study on the quality of beche-de-mer in trade and shrinkage of specimens during processing

The beche-de-mer industry in India is a cent percent export oriented industry being confined to south east coast in Palk Bay and Gulf of Mannar in Tamil Nadu. Chemical quality of 180 trade samples of beche-de-mer of four sizes collected from the beche-de-mer curing centres of Ramanathapuram district was studied. Moisture ranged from 6.2 to 24.4% and sand content from 0.11 to 20.42% for all grades. Mean values of sand content are for grade 1=3.47%, grade 2=4.50%, grade 3=3.68%, grade 4=6.87%. Sodium chloride was almost constant for all grades at 5.7%. TVBN values ranged from 10 to 78.4 mg%. 44 laboratory samples of different grades were prepared following trade practice and examined for chemical quality. Mean moisture values are for grade 1=13.4%, grade 2=12.44%, grade 3=12.62%, grade 4=12.08% and mean values of sand are for grade 1=0.70%, grade 2=0.90%, grade 3=1.16%, grade 4=2.15%. The percentage of shrinkage of the animals ranged from 56% to 60% for dried beche-de-mer of 7.5 cm size and above.

Antibiotic sensitivity of Staphylococcus aureus strains isolated from fishery products

During the course of an investigation on the incidence of Staphylococcus aureus contamination in frozen crab meat, frozen prawns and dried fishes from Cochin, 116 strains of S. aureus were isolated. The sensitivity of the isolated strains towards nine antibiotics showed that all the S. aureus strains were sensitive to kanamycin and streptomycin (100%). Sensitivity to other antibiotics like chloramphenicol, polymyxin-B, erythromycin, tetracycline, neomycin, penicillin and ampicillin were shown by 98.28, 93.10, 87.93, 68.10, 67.24, 56.90 and 55.17 percent of the isolates respectively.

Nutritional evaluation of fish solubles

This paper reports the results of a preliminary study on the biochemical composition and nutritional charactersitics of fish solubles from oil sardines (Sardinella longiceps) and white tailed pink perch (Nemipterus japonicus). The nutritional quality of sardine solubles has been evaluated by feeding trials using albino rats also. The studies have shown that compared to a control group of rats whose diet had casein as the sole source of protein, a group of rats in whose diet dried sardine solubles replaced half of the casein, had a noticeably higher growth rate. This higher growth rate was not prominent in the early stages of growth (4-7 weeks). But, during later stages (7-10 weeks), solubles incorporated diet supported a distinctly higher growth rate. This effect was more pronounced in female rats (17% over the control group) compared to the male rats (4% over the control group). Fish solubles are found to be poor sources of essential amino acids. Thus, the observed increase in growth rate is higher than the rate expected from the amino acid make up. This probably supports the view expressed by workers elsewhere that fish solubles contain some unidentified growth factors.

Preliminary chemical and physical evaluation of some formulated feeds for P. monodon

The culture of Penaeus monodon has explicitly defined the need for diet formulations or supplementary feeds that would promote optimum growth and survival of the animal. A total of 28 feed combinations were developed for P. monodon. Fish meal, shrimp head meal, squid head meal, Ascetes spp. rice bran, and soybean cake were used as primary ingredients in these feeds. The commercial vitamin mix No. 22 was added to the dry ingredients. Gelatinized corn starch and wheat flour were used as binders. The pellets were extruded using a portable kitchen grinder with a diameter of 4 mm. The products were either sun-dried for 8 hours or oven-dried overnight at 50 degree C to stabilize moisture at 8-10%. The pellets were then kept in covered glass bottles and stored in the laboratory at room temperature. The cost of the feeds excluding labour were also computed. The pellets were analyzed for protein, fat, carbohydrate, crude fiber, ash, and moisture contents using standard procedures. They were also analyzed for water stability. To test the stability of pellets in water, 2-g samples were placed in plankton nets (mesh #40) and suspended in water for two, and six hours. The undissolved samples were then vacuum-dried and the moisture determined. Cost of the feeds ranged from P1.10 to P2.60 per kg depending on the feed ingredient. Squid and Ascetes spp. were rather expensive for use as basic ingredients. Proximate analysis of dry weight showed percentage protein content ranged from 20-63 g; fat, 8-20 g; carbohydrate (by difference), 11-36 g; ash, 8-28 g; moisture, 6-11 g; and crude fiber, 5 . 13 g. Stability tests showed that after two hours, 35-88% of solids remained intact and after 6 hours, 20-55% of the pellets remained undissolved. When a pellet disintegrates easily, pollution of the water occurs. Chances for the shrimp to feed on the pellet is minimized when the pellet is unstable. Thus, the search for a more compact feed pellet has to be continued.

Survival rates of different postlarval stages of Penaeus monodon Fabricius

The objective of this study is to determine survival rates of different postlarval stages upon stocking in the Leganes ponds. Twelve 3m x 2m x 2m suspension nets made of nylon cloth (mesh size = 0 . 1 mm) were set up in a Leganes Station pond (ave. water depth = 1 m) by means of 3-m long poles stacked at distances approximating the area of each net. The net bottom was filled with topsoil at least 15 cm thick to stimulate the pond bottom. At least 60 cm of the upper edge of each net was above the water level to prevent mixing of water inside and outside the net. P.monodon of stages P SUB-11 , P SUB-15 , P SUB-21 (from the hatchery) and P SUB-25 (from the wet lab) were stocked in the nets at 200/sq m or 1,200 fry/net. Due to lack of fry, only one P SUB-25 net was stocked. Each net had two large dried miapi branches as shelter from predation and cannibalism for the young sugpo fry. Fresh lablab was fed at the rate of one pail (approximately 5 kg) every four days per net. Harvest data show relatively higher survival rates for P SUB-15 and P SUB-18 compared to P SUB-11 and P SUB-25 with no significant difference between these two stages. The results for P SUB-25 may not be valid because the stock came from the wet lab in comparison to the other postlarval stages which were reared in the hatchery. Moreover, the P SUB-25 stock had no replicates and the net itself (no. 10) was discovered to have many holes. These preliminary results point to P SUB-15 as the best stage for harvest from the hatchery in terms of high pond recovery and lesser expense in rearing compared to older postlarvae.

Utilisation of squid waste as meal

The squid waste which includes head, tentacles, viscera, fin, skin and pen amounts to 52% of the whole weight and is discarded at present. A method has been worked out for the conversion of squ.id waste into meal. The waste is boiled in salt solution (2%)/salt (2%) and alumn (0.5%) solution/and water for two minutes, drained and dried. All the dried samples including the control (dried without blanching) were analysed for physical and biochemical changes. Blanching reduced the yield but the product could be dried in a shorter period. The volatile bases were reduced significantly and the colour was improved. Blanching made pulverisation of the dried product easy. Pulverisation before drying yielded a granular product.

Quality of cured fish from the Maharashtra coast

Chemical, bacteriological and organoleptic characteristics of sun dried/dry salted fish collected from five major centres of coastal Maharastra [sic] are reported. Wide variations are seen in the quality of the different samples. In dry salted products, moisture ranged from 16.17 to 46.58%; salt from 5.18 to 22.75%; acid insoluble ash from 1.0 to 6.8%. In sun dried samples moisture varied from 16.15 to 39.51% and acid insoluble ash from 0.42 to 2.82%. The sun dried samples, though no salt was used in the process, showed fairly good amount of salt.

Preserved algae as food for Penaeus monodon larvae

Uni-algal cultures of C. calcitrans, S. costatum, T. chui and Isochrysis sp. obtained from the laboratory were harvested. The harvest, preserved by either freezing or sun-drying, was fed to the larvae of P. monodon . Among the test algal species, Chaetoceros and Tetraselmis were used in larval feeding trials with frozen food while Chaetoceros, Tetraselmis and Isochrysis species were utilized in feeding experiments with sun-dried algae. Their relative effects on larval survival and development were assessed. Results showed that, except the alum-flocculated cells, both frozen Chaetoceros and Tetraselmis can support survival at the zoea stage. Best survival of 68% was atained with dried Chaetoceros followed by Tetraselmis at 44%. Dried Isochrysis did not perform as well, a significantly low survival of only 25% was obtained.

Feeding behavior and food preference of Penaeus monodon Fabricius with scrap tilapia

The time of day during which P. monodon feeds at different depth levels in earthen ponds, and its preference for three types of tilapia feeds (dry, fresh and fermented) were determined. It was observed that P. monodon concentrated at the bottom beds during the day and along the periphery of dikes during night-time, with a slight tendency to swim and feed towards the surface as darkness increased. P. monodon showed special preference for dried tilapia compared to fresh and fermented tilapia. P. monodon also showed adaptability to the platform method of feeding, especially during night-time.

Incidence and low temperature survival of Salmonella in fishery products

Salmonella was isolated from 12% of PD shrimps, 10% of HL shrimps, 14% of PUD shrimps, 17% of lobsters, 14% of cuttle fish, 25% of cat fish and 20% of seer fish (all frozen) tested. One percent of the fish meal, 4% of dried non-penaeid prawn and 23% of sea beach sand showed incidence of the organism. Salmonella was also isolated from 2 and 4% of the swab samples of utensil surfaces and the floor surface of the processing hall respectively as well as from 1% of the process water tested. All the serotypes of Salmonella tested were resistant to freezing at -40°C, but during subsequent storage at -20°C, there was some difference between the serotypes with regard to their viability, S. paratyphi B being the most resistant which survived up to 9 months while S. saintpaul the least resistant having survival up to 5 months only.

Quality of dry fish from markets in Andhra Pradesh

Dry fish samples were procured from different fish markets and subjected to biochemical and bacteriological evaluation for assessing quality. The quality of market samples was compared with the samples dried in laboratory and in the mechanical drier [sic]. Most of the market samples had high moisture and sand contents. TVN values of market samples were high showing poor quality of the finished product.

Estimation of yield of dry air bladders from eel fish

The findings are presented of a study conducted to determine a method for the calculation of the yield of dried air bladders of eel from the weight of the whole fish.

Comparative feature on design, construction and installation of three different model of low cost solar tunnel dryers

The study was conducted in collaboration with the ECFC project of the FAO (BGD/97/017) in Cox's Bazar to develop a low cost solar tunnel dryer for the production of high quality marine dried fish. The study areas were Kutubdiapara, Maheshkhali and Shahparirdip under Cox's Bazar district. Three different models of low cost solar dryer were constructed with locally available materials such as bamboo, wood, bamboo mat, hemp, canvas, wire, nails, rope, tin, polythene and net. Size of the dryers were: 20x4x3 ft ; 30x3x3 ft and 65x3x3 ft with the costs of Tk. 3060, 3530, 9600 for dryer 1, 2 and 3, respectively having different models. The drying capacities were 50, 150, 500 kg for dryer 1, 2 and 3 respectively. The average temperature range inside the dryers were 29-43°C, 34-51°C and 37-57°C for dryer 1, 2 and 3 respectively as recorded at 8:30h to 16:30h. The relative humidity were in the ranges of 22-42%, 27-39% and 24-41 % in dryer 1, 2 and 3 respectively. The fish samples used were Bombay duck, Silver Jew fish and Ribbon fish. The total drying time was in the range of 30-42, 28-38 and 24-34 hours to reach the moisture content of 12.3-14.5, 11.8-14.3, and 11.6-14.1% in dryer 1, 2 and 3 respectively. Among these three fish samples the drying was faster in Silver Jew fish followed by Bombay duck and Ribbon fish in all the three dryer.

Application of encapsulated nisin and sodium citrate for shelf life increasing of Rainbow trout (Onchorhynchus mykiss) fillet packaged with MAP and their effect on Staphylococcus aureus

Nisin is a widely used naturally occurring antimicrobial effective against many pathogenic and spoilage microorganisms. It has been proposed that reduced efficacy of nisin in foods can be improved by technologies such as encapsulation to protect it from interferences by food matrix components. The aim of this study was using of spray dried encapsulated nisin with zein in concentration of (0.15 and 0.25 g/kg) and sodium citrate (1.5 and 2.5%) and treatments with both of them to extent the shelf life of filleted trouts packaged by Modified Atmosphere Packaging (45% CO2, 50% N2 ,5% O2) and stored at 4±1 °C for 20 days. Furthermore, to evaluate the antimicrobial efficiency of encapsulated nisin and soudium citrate the trouts fillets was inoculated with Staphylococcus aureus as an index pathogenic bacteria. Assessment of chemical spoilage indexes such as (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) , microbial parameters (Total Plate Count, Psychrotrophic count, Lactic acid bacteria count), Staphylococcus aureus cont in treatments which were inoculated with 5 logcfu/g of this bacteria and sensory evaluation of fillets including (smell, color, texture and total acceptability) was carried out in days of 0, 4, 8, 12, 16 and 20. The results revealed that treatment with both exposure of nisin and sodium citrate showed significantly lower chemical spoilage indexes in comparison with controls (vaccum packed and MAP) (P<0.05). Furthermore, (nisin 0.25 g/kg sodium citrate 2.5%) treatment which was exposed to the maximal level used of both materials was significantly the lowest treatment with (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) of 9.95 (meq O2/kg) , 1.55 (mgMA/kg), 29.65 (mgN/100g) and 6.65 , respectively and according to the maximal recommended level of this indices , shelf life of fillets in this treatment was esstimated 20 days.The control (vaccum packed) treatment was significantly the highest treatment with (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) of 15.17 (meq O2/kg), 3.03 (mgMA/kg), 38.4 (mgN/100g) and 6.95 , respectively and according to the maximal recommended level of this indices , shelf life of fillets in this treatment was estimated 11 days. Also, in microbial point of view (nisin 0.25 g/kg- sodium citrate 2.5%) treatment was the lowest treatment with Total Plate Count, Psychrotrophic count, Lactic acid bacteria count and Staphylococcus aureus count of 6.7, 6.83, 5.25 and 6.04 logcfu/g respectively, and conrol (vaccum packed) treatment was the highest treatment with 9.15, 9.41, 7.7 and 9.01 logcfu/g respectively. According to the lower results of chemical and microbial indices and higher sensory evaluated scores assessed in this research for encapsulated nisin in comparison with free nisin , it was concluded that encapsulation of nisin with zein capsules may improve the efficiency of nisin. The measuremented values of Mass yield, Total solids content of capsules, Encapsulation efficiency, In vitro release kinetics in 200 hour for encapsulated nisin in this study was 49.89, 62, 98.31 and 69% respectively and Encapsulated particle size was lower than 674.21 μm for 90% of particles. As a consequence, nisin , in particular encapsulated nisin, and sodium citrate alone or together with and Modified Atmosphere packaging might be considered as effective tools in preventing the quality degradation of the fillets, resulting in an extension of their shelf life.