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ThesisItem Open Access ENHANCEMENT OF GEL STRENGTH OF CROAKER SURIMI USING EXTRACTS OF BROWN SEAWEED (Padina tetrastomatica) AND GREEN SEAWEED (Caulerpa sp.) POOJA SIDDHARTH (Accession No. T06758)(dbskkv., Dapoli, 2019) GAMARE, POOJA SIDDHARTH; Sawant, S. S.Surimi is Japanese term which can be defined as concentrated myofibrillar protein obtained from fish flesh by washing to remove lipids, bloods, sarcoplasmic proteins and enzymes and mixed with cryoprotectants for frozen storage. Recently, plant phenolic compounds are used as protein cross-linkers. In present study, the brown seaweed (Padina tetrastomatica) and green seaweed (Caulerpa peltata) available along Ratnagiri coast of India were used. The total plant phenolic compound extracted from both brown and green seaweed as protein cross-linkers in croaker fish surimi. Water seaweed extract of Padina tetrastomatica (Brown) and Caulerpa peltata (Green) contained 16.75 and 15.34 mg tannin/g of dry seaweed powder. The effect of addition of different concentrations (0.0%, 0.2%, 0.4%, 0.6%, 0.8%)of seaweed on croaker surimi gel were studied. The 0.6% concentration of brown and green seaweed with surimi gel showed significantly increase in gel strength compared with control (P<0.05). The lower moisture content was showed in 0.6% concentration of surimi gel with both seaweeds concentration. However, addition of brown and green seaweed had slightly decrease in whiteness (P<0.05). During study low protein solubility (%) was found that, at 0.6% concentration of both seaweeds extracts. The addition of brown and green seaweed extract showed the minor increase in pH with increasing concentrations, which was not significant difference compared with control surimi gel sample (P>0.05). Folding test indicates that, the high score was found in 0.6% concentration of surimi gel with both seaweed compare to control. Therefore, it may be concluded that, the brown and green seaweed extract used as gel enhancer in croaker surimi has no changes in texture and flavour.ThesisItem Open Access ENGINEERING ASPECTS OF OPERATIONAL BRACKISH WATER FARMS OF RAIGAD, MAHARASHTRA(dbskkv., Dapoli, 2018) BANSODE, VIKRANT VISHNU; SHARANGDHAR, M. T.Present study was taken to investigate the engineering aspects of the operational brackish water farms of Raigad. Raigad district was divided into three regions namely North, Central and South Raigad Region for the study. Farm details like general information, site selection, design, leading canal, shape of pond, specifications of ponds (length, width, depth, pond bottom slope, pond and water spread area), dikes (Peripheral and Partition dikes), drainage canal, drainage canal dike, catwalk, sluice gate, water supply system, were measured and other infrastructure parameters such as approach road, farm stead and electrical distribution system were also taken in consideration. Soil characteristics like moisture, pH, electrical conductivity, water holding capacity, bulk density and texture of operational brackish water farms of Raigad were analyzed. Water quality parameters like salinity, temperature, pH, dissolve oxygen, ammonia, total alkalinity, total hardness, and transparency were observed. Layouts of the selected farms were prepared from data collected during the study period. In Raigad, forty-three brackish water farms were observed to be operational. Total area of the brackish water farms 0.5 to 50.0 ha comprising of the 2 to 47 ponds and having a total water spread area of 0.3 to 48.90 ha. Leading canal was not observed for any of the 43 farms of Raigad district as the location of the creek was near to the farm area and all the farms were observed to be pump-fed. The length of the ponds ranged between 28.75 to 280 m and width of the ponds was 18.80 to 231.59 m each. The maximum depth was found to be 1.5 to 2 m. Pond area and water spread area was 0.07 to 2.5 ha and 0.05 to 2.2 ha. Pond bottom slope was 1: 1000 to 2:1000 (Vertical: Horizontal). On the brackish water farms, top width of the peripheral dike was 1.3 to 2.80 m. The side slope and free board was 1:1 to 1:2.5 (Vertical: Horizontal) and 0.30 to 0.60 m respectively. The height of the dike was 1.8 to 2.2 m. On the top width of the partition dike ranged from 0.8 to 2.5 m. The side slope was 1:1 to 1:2.5 (Vertical: Horizontal) and the free board 0.2 to 0.5 m. The height of the dike was 1.5 to 2.0 m. The top width of the drainage canal was 2.60 to 20.5 m. The bottom width was 1.5 to 15.6 m and the depth was 2.0 to 3.5 m. On the top width of the drainage canal dike was observed to be 1.4 to 2.8 m and a freeboard of 0.4 to 2.0 m. In the Raigad district farms, catwalks were constructed by using bamboo, wooden poles and wooden planks. Length and width of the catwalk was observed to range from 4.0 to 16.0 m and 0.44 to 2.5 m. The height of the catwalk from the pond bottom was found to be 1.5 to 3.0 m. It was observed that in some brackish water farms had constructed a feeder canal made of brick and cement. The top width of the feeder canal was 0.65 to 1.80 m and depth 0.20 to 3.0 m. The other farms used PVC pipes, Hose pipes, Canvas and HDPE pipes for supply of brackish water to the ponds. The inside and outer diameter of pipe varied from 30 to 250.0 mm and 31.2 to 251 mm. On the brackish water farms, the sluice gate was found to be constructed in the ponds. The width and height of the sluice gate was observed to be 1.30 to 3.65 m and 2.0 to 3.0 m. Sluice gate was constructed with the help of bricks and cement while in some farms hume pipe was used for drainage pipe hume pipe diameter and length were within range of 300 to 1000 mm and 2.5 m. Sluice gates were provided with three to six numbers of grooves for fitting screens with 60 micron mesh cloth. Water level within the ponds was maintained by fixing 10 to 16 numbers of wooden planks in the two adjacent grooves of the sluice gate and filling the area between them with mud. High-density polyethylene (HDPE) lining was observed in some farms for preventing seepage of water from the ponds. The thickness and shelf life was 0.3 to 0.5 mm and 5 to 7 years. Instruments and equipments used for the farms were pump, aerator, blower, check tray, auto feeder, CCTV, refractometer, DO meter, pH meter, and weighing balance. On brackish water farms the source of electrical power supply was from Maharashtra State Electricity Board (MSEB) and having transformers of 60 to 200 kVA capacity. The alternating power supply was available in the form of diesel generator of 15 to 250 kVA capacity. In the Raigad district brackish water farms, soil texture was Sandy loam and Loamy sand soil. Other soil parameters of the brackish water farms like soil parameters moisture, pH, electrical conductivity, water holding capacity and bulk density were in the range of 2.33 to 16.42 %, 7.0 to 8.5, 1.03 to 5.47 dS/m, 31.47 to 92.17 % and 0.29 to 1.57 g/cm3 respectively. The water quality parameters like salinity, temperature, pH, dissolve oxygen, ammonia, total alkalinity, total hardness and transparency of brackish water farms were analyzed the results obtained were as 15 to 35.5 PSU, 24.2 to 30 0C, 7.2 to 8.2, 3.5 to 6.7 mg/l, 0.0 to 0.05 ppm, 90 to 140 mg/l, 85.4 to 120 mg/l and 24.5to 40 cm respectively. In all farms under Raigad district strictly biosecurity measures such as animal fencing, bird fencing, crab fencing, hand wash, footbath etc. were religiously followed to prevent viral outbreak. This strict biosecurity practices are the major steps, makes more successful crop for all Raigad district brackish water farmers.ThesisItem Open Access INDUCED MOULTING OF MUD CRAB BY SPINACH EXTRACT FOR PRODUCING SOFT SHELL (Accession No. T06566)(dbskkv., Dapoli, 2018) SHAHARE, AJAY NEMICHAND; NAIK, S. D.Moulting stimulant made was prepared by from spinach extract. The objective of this study was to standardize the optimum dose of spinach extract for inducing the moulting of crab and to study the required moulting period of crab. The research was carried out in indoor culture system in polypropylene boxes (18 x 12 x 8 inch). In this system, the water parameters were maintained, temperature-27-32⁰C, salinity-16-30ppt, dissolved oxygen-≥ 5 ppm and pH-7.5-8.5. The experiment was carried out as per Completely Randomized Design (CRD) with four treatments and five replicates to evaluate the effect of growth and moulting period in mud crab. There were three doses of spinach extract doses tested, without injection (control). 0.015 mg/g of crab, 0.02 mg/g of crab and 0.025 mg/g of crab. The result showed that the dose of spinach extract injection had great influence on the growth parameter (weight, length, width) and moulting period of mud crab. Spinach extract dose of 0.025 mg/g of crab showed the higher growth percentage i.e. weight gain (70-72%), length gain (29-34 %), width gain (25-27 %) and moulting period required was 30-32 days. However, in term of productivity, dose of 0.025 mg/g of crab showed the better result for soft shell production of mud crab.ThesisItem Open Access SPATIO - TEMPORAL METAGENOMIC PROFILING OF BACTERIAL DIVERSITY OF AQUACULTURE SEDIMENTS UTKARSH (Accession No. T06564)(dbskkv., Dapoli, 2018) CHACHARKAR, UTKARSH SURENDRA; PAWAR, R. A.Bacterial communities in commercial freshwater (IMC) and brackishwater shrimp aquaculture pond sediments were analysed using the culture-independent metagenomic profiling approach. The bacterial communities were identified using V3-V4 paired hyper variable regions of 16S rRNA combined with next-generation sequencing. The assay revealed the bacterial community structure of the sediments and identified 3416 OTUs from 1124212 QIIME QC filtered sequencing reads for bottom sediments of both aquaculture activities including source for shrimp aquaculture activity. The present study found the predominance of phylum Proteobacteria (~ 99%) from both aquaculture types followed by Chloroflexi (0.02%), and others in decreasing order. At order level, about 50% the bacterial population remained unclassified with Aeromonadales, Alteromonadales, Enterobacteriales, Pseudomonadales, aaa34a10, Rhodocyclales, Rhizobiales, Desulfuromonadales, Rhodospirillales, and others as the remaining major orders. Comparison of the fish and shrimp farm OTUs revealed 27.5% sharing of OTUs between the two aquaculture activities. Thus, only about 64.6% of the OTUs were unique for the freshwater IMC system. Comparisons between different stages of shrimp farms indicated 12.8% (SS/S1), 6.3% (S1/S2), and 4.4% (SS/S2) of shared OTUs. Statistical comparisons between the „initial‟ and „final‟ metagenomic profiles obtained from shrimp farm sediments (SS→S1→S2) revealed no significant differences based on the Mann-Whitney U-test (P > 0.05). Regression analyses showed that the overall trends with respect to OTUs (total, shared, or unique) had a „large‟ „effect size‟. Similarly, at phylum- and order-level respectively, about 73% and 80% of the profiles displayed trends that translated into a „large‟ ES. The study reveals that aquaculture practices influence the relative abundance of bacterial entities and that the Proteobacteria (Gammaproteobacteria) are important for the health of aquaculture sediments.ThesisItem Open Access DEVELOPMENT OF BISCUITS USING RIBBON FISH, Trichiurus lepturus (Linnaeus, 1758) (Accession No. T06565)(dbskkv., Dapoli, 2018) CHITKARE, GANGADHAR BHAGWANRAO; Vishwasrao, V. V.In the present study an attempt has been made to develop a snack product i.e. fish biscuits from ribbon fish (Trichiurus lepturus). The developed product “fish biscuits” was stored at room temperature for shelf life study. Ribbon fish can be used as a raw material for value added minced based product development. During this research work, physical, biochemical, microbiological and organoleptic evaluation of fresh fish as well as product were carried out. After meat separation, a ribbon fish biscuit was prepared by standardizing the ingredients in different ratios viz; fish meat powder and butter, white flour, common salt, cardamom, cumin and chilli flakes. Among the different ratios of ingredients to ribbon fish meat, ribbon fish biscuits was prepared with cardamom was 1:100 (w/w), chilli flakes was 1:100 (w/w), common salt was 1:100 (w/w), cumin was 2:100 (w/w), fish meat powder was 15:100 (w/w), butter was 25:100 (w/w) and white flour was 55:100 (w/w) was found superior than that of biscuits prepared with other ratios. By using standardized recipe, the biscuits were prepared and kept at room storage for assessment of shelf life. The product was subjected to organoleptic evaluation, biochemical and microbiological tests at regular intervals of 15 days at room storage respectively. During storage study, it was found that, the ribbon fish biscuits kept at room storage was acceptable up to 120 days.ThesisItem Open Access HYDROBIOLOGICAL STUDIES ON CORAL REEF AREA OF MALVAN, SINDHUDURG DISTRICT. (Accession No. T06558)(dbskkv., Dapoli, 2018) BHATKAR, AJAYA ANIL; ADSUL, A. D.The present study was carried out to determine the hydrobiological parameters in relation with plankton abundance and monthly variation at five sampling stations of Malvan coral reef area during Feb-17 to May-17 and Oct-17 to Jan-18. Monthly variation of physicochemical parameters viz., atmospheric temperature (28.6 to 33°C), water temperature (27.6 to 33.2°C), light penetration (160 to 191 cm), pH (8.08 to 8.86), dissolved oxygen (2.16 to 7.12 mgl-1), alkalinity (159.2 to 199.6 mgl-1), TDS (34.51 to 61.19 mgl-1), TSS (1.48 to 4.63 mgl-1) and salinity (30.0 to 34.42 psu). The variation in nutrient concentration of nitrate, phosphate and silicate ranged from 0.23 to 0.56 μMl-1, 0.12 to 0.39 μMl-1 and 0.43 to 2.51 μMl-1 respectively. The recorded values of Chlorophyll-a varied from 0.219 to 0.377 mg/m3. A total 56 species of phytoplankton representing different groups viz., diatoms (40), dinoflagellates (14), silicoflagellates (1) and unidentified (1) were recorded. Among the phytoplankton, diatoms such as Bacillaria sp. appeared to be dominant group in respect of total number of phytoplankton species. The zooplankton community comprised of 41 species among which the copepod nauplii, Acartia sp. and Oithona sp. occurred dominantly throughout the study period. Dissolved oxygen showed positive significant correlation with salinity and Chlorophyll-a, while TSS showed positive correlation with salinity and phosphate. Also positive correlation observed between salinity and phosphate; phytoplankton and zooplankton. The negative significant correlation was observed between air temperature and salinity and between light penetration and pH. The species richness and diversity indices were maximum in post-monsoon and minimum in pre-monsoon season.ThesisItem Open Access QUALITY ASSESSMENT OF POPULARLY SOLD DRIED SEAFOODS OF RATNAGIRI(dbskkv., Dapoli, 2019) KARANGUTKAR, TEJASWITA BHARAT; Sawant, S. S.In present investigation quality assessment of dried sea foods popularly sold in Ratnagiri Tehsil was carried out. Dried sea food samples of acetes, hunter shrimp, Indian mackerel and bombay duck each were drawn at random (4 samples from a retailer) during monsoon, winter and summer seasons from three retailers each identified at Ratnagiri fish market and Aathwada Bazar (weekly market). Samples were collected in plastic bags and then brought to laboratory and further analysed for proximate composition, biochemical and microbiological quality assessment. Quality assessment revealed that, in monsoon dried sea food was not found in good condition. Two way ANOVA with replications showed significant difference in quality of dried sea foods from different seasons. Maximum number of bacteria and fungi recorded in monsoon season confirms that moisture leads to contamination of dried fishes. The proximate composition of different dried fishes from Ratnagiri revealed that dried sea foods have very good nutritional value. TMA-N and TVB-N values were showing decreasing trend in winter and summer. TMA-N was observed above acceptable limit only in dried mackerel and TVB-N was found above acceptable limit in mackerel and bombay duck. FFA content of all the dried sea foods was found above acceptable limit. Microbiological analysis showed that dried sea foods sold in Ratnagiri were contaminated with bacteria and fungi in different seasons. But, then also all sea food samples from Ratnagiri were found to be in acceptable limit. Dried sea food samples were found to be free from Staphylococcus aureus. The result of the present study on quality assessment of popularly sold dried sea foods of Ratnagiri is an alarming signal for the consumers about the quality of sun dried sea foods. Therefore, it is important to train local fisher folk on proper processing and preservation to improve the quality of dried sea foods for the benefits of the consumers.ThesisItem Open Access DESIGN ASPECTS OF MARINE GILL NETS OF SINDHUDURG DISTRICT, MAHARASHTRA (Accession No. T06393)(dbskkv., Dapoli, 2017) WAGHMARE, KISHAN VASANTRAO; SADAWARTE, R. K.In Sidhudurg, Gill nets were preferred by most of the fishermen as fishing gear due to cheap and easy to operate. A study on the marine gill nets of Sindhudurg was undertaken to study the design and technical characteristics of gill nets. Three fish landing centers from Sindhudurg where gill net fishing is actively done were selected for the study. The nets were classified into different groups and the technical specifications of each type were detailed. Nets of mesh sizes ranging from 46 to 200 mm targeted at different species of fishes found in Sindhudurg. The natural fibers in gill nets had almost completely replaced by synthetic materials like polyamide. PA monofilament and PA multifilament material was most popularly used for gill nets were targeted for mackerel, whitefish, pomfret, shrimp, red snapper and seer fish, respectively. In Sindhudurg, PA monofilament of diameter 0.20 to 0.28 mm was used as webbing material for drift type of mackerel gill net. The mesh size for the mackerel drift gill nets ranged between 46 to 56 mm. The main webbing of whitefish gill nets fabricated with PA monofilament of 0.20 to 0.23 mm diameter with mesh size ranged from 46 to 48 mm. Gill nets for seer fish were operated as drifting gear at the surface or in the column water. PA multifilament twines having specifications of 210d×6×3 to 210d×12×3 were used according to the mesh size. The mesh size ranged between 90 to 140 mm. PA monofilaments of 0.23 to 0.32 mm diameter were exclusively used for pomfret gill net as the material for the main webbing of the net. The mesh size ranged between 115 to 125 mm. Shrimp gill net in Sindhudurg was the common type of bottom set trammel net with loosely hung small meshed panel present between two tightly hung large mesh panels. The material used for inner small mesh panel was exclusively of PA monofilament of 0.16 to 0.20 mm diameter and for outer large mesh panel was of PA 135 multifilament of specification 210d×2×3. Mesh size ranged between 46 to 48 mm with most common of 46 mm for inner small mesh panel and of 240 to 250 mm for the two outer identical panels. In Sindhudurg, red snapper gill nets were made up of PA monofilament material of 0.80 mm diameter with mesh size varying between 195 to 200 mm. The twine size-mesh size ratio for PA monofilament used for target species like mackerel, whitefish, pomfret, shrimp and red snapper gill nets, the ratio ranged between 0.002 to 0.005 whereas for PA multifilament commonly used for seer fish gill nets operated from Sindhudurg was estimated as 0.01. For gill net fishing in Sindhudurg, vessels ranging from 4.45 m to 10.40 m LOA were used. These included plank built canoe with or without outrigger, wooden, FRP coated wooden and FRP boats. In Sindhudurg, motorized and mechanized fishing vessels were engaged in gill net fishing operation.ThesisItem Open Access POST- HARVEST CHARACTERISTICS AND THERMAL PROCESSING OF FRESH WATER EEL (Mastacembelus armatus) (Lacepade,1800)(Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli , Dist : Ratnagiri, 2017) MUGALE, ROHINI RAVAJI; Patange, S. B.Eel (Mastacembelus armatus) is a white fleshed lean fish which is economically and nutritionally important in the inland regions of Maharashtra. It fetches better price over Indian major carps. The meat of the fish is white and firm in texture and therefore a delicacy among fish consumers. The fish has wider distribution in rivers and majority of the water bodies of the state and is marketed throughout the year. Studies were conducted to evaluate post-harvest storage characteristics during chill storage with the effect of potassium sorbate on the shelf life of fish under air and vacuum packaging. Further, the effect of ice storage on the functional characteristics of fish muscle proteins were also evaluated in order to assess its potential in preparation of various products using its functionality. Preservation of the fish in the form of value added fish in curry and fish in brine was also carried out to evaluate the shelf life in the retort pouch packaging. With regard to ice storage characteristics, storage life was evaluated under air and vacuum packaging of eel steaks that were treated with potassium sorbate (PS) at a concentration of 0.5, 1.0, 1.5 and 2.0% and stored under chilled condition. During storage, the changes in biochemical (pH, TVB-N, AAN, PV, FFA and SSN), microbiological (APC and E. coli) and organoleptic characteristics were monitored for a period of 22 days with analysis of each parameter monitored for every alternate day. During storage, the pH, TVB-N, AAN, PV and FFA content of both control, air and vacuum packed samples; and treated air and treated vacuum packed samples were gradually increased 98 during storage period. The SSN steadily decreased due to denaturation of proteins during chill storage. It indicated that, the extent of deterioration in fish was seen early in control packs on 10th day, in vacuum pack on 14th day and 16th & 18th day in treated air and treated vacuum packed samples during chill storage. The APC of control samples and treated samples showed increasing trend during chill storage and among all the treatment levels, 2% PS treated samples had better sensory scores for all the attributes than other treatment levels. Organoleptic, biochemical and microbiological analysis revealed that, the air packed samples without treatment had shelf life of 12 days while, untreated vacuum packed samples had shelf life of 16 days. The samples treated with four levels of potassium sorbate packed under air had shelf life of 18 days each whereas, treated samples packed under vacuum had the shelf life of 22 days each. Based on these observations, it is concluded that a combination of vacuum packaging and treatment with potassium sorbate (2%) significantly (p< 0.05) increased the storage life of eel steaks in ice. The functional properties of eel muscle were evaluated in order to examine its potential in the preparation of emulsion or sausage type foods. For this purpose, changes in functional properties during chill storage were studied for a period of 16 days. During storage, changes in physico-chemical properties of proteins such as, solubility, gelation, viscosity, water holding capacity (WHC), emulsion activity index (EAI), emulsion stability (ES) foam expansion and foam volume stability (FVS) were evaluated for a period of 16 days with the analysis of each parameter monitored for every alternate day. 99 The solubility of muscle proteins i.e. MFP decreased from 59.16 to 51.89 mg / g during chill storage. With reference to gelation property which is important in gelation type products, the gel strength of MFP decreased slowly from 250 to 247g.cm during first 4 days and then markedly decreased from 240 to 100 g.cm from 6th day onwards up to 16th day of storage. The Ca2+ ATPase activity of actomyosin gradually decreased during storage. The emulsion activity index (EAI) and emulsion stability (ES) of MFP at concentration of 5.0 mg/ml also decreased continuously from 3.1 to 1.3 m2/g and 60 to 40 min respectively during chill storage. The foaming expansion and foaming volume stability (FVS) at concentration of 5.0 mg/ml showed decreasing trend during chill storage. The viscosity of MFP and SPP at concentration of 5.0 mg/ml decreased gradually during chill storage. The water holding capacity (WHC) of muscle also reduced during chill storage. The electrophoretic separation of MFP on PAGE showed the protein bands with myosin heavy chain and actin and the bands did not show any appreciable displacement on PAGE indicating no denaturation for 7 days in ice. Several low molecular weight bands were observed in the SDS-PAGE pertaining to sarcoplasmic proteins. The studies on effect of filling medium on thermal processing characteristics with eel steaks in curry and brine were carried out. These products were processed for 2, 3 and 4 min at 121oC at the process value of 5.03, 17.52 and 16.75 min for curry medium and 6.08, 13.89 and 5.03 min for brine medium respectively. Among these, the products processed for an Fo values of 17.52 and 13.89 respectively were shelf-stable for a period of 210 and 180 days respectively. Higher lethality values for brine were observed 100 than eel in curry during thermal processing. Heat penetration characteristics such as, process value (Fo), slope of heating curve (fh), time in min for sterilization at retort temperature (U), fh/U, temperature deficit (g), process time (B), cook value (Cg), come-up time (CUT) and total process time (TPT) were calculated using standard methods. Upon thermal processing, the products were evaluated for textural attributes such as, cohesiveness, toughness, succulence and fibrosity. Based on sensory and textural attributes eel steaks in curry and brine processed for an Fo value 17.52 and 13.89 min respectively had better acceptability. When tested for commercial sterility, the products were commercial sterile. These products were evaluated for storage performance for 240 days. During storage, biochemical (pH and TVB-N) and sensory observations were made to evaluate the acceptability of products. Sensory scores for visual attributes showed significant difference over the storage period within and between these products. However, the texture attributes was constant until 180 days. On the basis of sensory, biochemical and microbiological analysis, it was observed that the eel steaks in curry and brine processed for 3 min at 121oC gave shelf life of 210 and180 days respectively at ambient temperature (30 ± 2 oC).