Dr. Md. Shaheed Reza Associate Professor Dept. of Fisheries Technology Faculty of Fisheries Bangladesh Agricultural University Mymensingh-2202 Bangladesh
Abstract: Studies were conducted to evaluate the present status traditional dried punti (punti shutki) and semi-fermented fish products (chepa shutki) in Mymensingh district, Bangladesh. A survey was made on the source of raw material, handling, transportation and production process, preservation of finished products and quality aspects of the finished products using questionnaire through interview among cross section of people involved in value chain. It was found that semi-fermented fish products were produced in winter season using punti shutki. After harvesting, the small-scale fishermen carried their catch to the landing center in traditional bamboo baskets without adequate ice. Boat, rickshaw, van etc. are mainly used to transportation of fish using steel made ice box, bamboo basket and plastic drum. It was observed that there were facilities of ice storage in each depot in the study area. The producers, wholesalers and retailers had adequate knowledge about the production techniques of traditional dried fish and chepa shutki but they have little or no idea about the quality management of the products. Their marketing chain varied between season to season and place to place. The storage duration of the traditional dried punti and chepa shutki varied from 1-8 weeks and 3-6 months, respectively at different levels from producer to retailer. Although there were frequent complaints from the consumers about the use of insecticides in the fish products for prolonging shelf life during storage, the wholesalers and retailers did not admit the use of any insecticide or preservatives in their products to prevent insect infestation. In terms of storage technique, 64% retailers stored their products in clay vats whereas remaining 36% retailers stored in plastic bucket or wooden box without any proper packaging.
Abstract: A survey conducted on the marketing system of traditional dried and semi-fermented fish product locally called âchepa shutkiâ of Bangladesh showed that there was no fixed marketing channel for those products and the length of marketing chain varied depending on location and season. Generally the processors collected raw materials from fishermen, middlemen or through a number of intermediaries, and processed the fish to sell them to wholesalers. About 45% of the local retailers purchased chepa shutki directly from processors to ensure maximum profit. It was found that 73% retailers had idea about the production technique of dried products; 68% of the retailers took no protective measures to preserve the quality of the products while 9% retailers separated the broken pieces from the lot before selling their products. Sixty four percent retailers stored the products in earthen vats while others stored the product in plastic bucket or wooden box. It was found that they had little or no idea about the quality management of their products. The survey revealed that 68% of the local retailers thought that chepa shutki retailing was a profitable business while 73% retailersâ main occupational activity was chepa shutki and dried fish retailing and the remainders had other forms of business including grocery-cum-dried fish retailing. In case of education level retailers, it was found that 55% were illiterate while 25% of them received formal education. About 65% of the retailers had family member less then 5 and the remainders had more than 10 members in their family. Sixty three percent respondents among the retailers were muslim and the rest belonged to hindu religion. The study showed that 63% of the retailers were satisfied with their existing socio-economic condition and they ranked themselves in the society as businessmen.
Abstract: Proximate composition of semi-fermented fish products (locally known as chepa shutki) obtained from producer, wholesaler and retailer were analyzed. Moisture content varied from 39.62 to 46.89% with the highest value recorded in the products obtained from retailer and lowest in that obtained from producer. Protein, the most important component among the chemical composition, ranged from 32.46 to 33.83% with highest value recorded in product obtained from producer and lowest value in those obtained from retailer. Lipid content, on the other hand, varied from 19.25 to 24.97% with highest value recorded for the products obtained from producer and lowest value in products obtained from retailer. Similar trend was also observed when the values of protein and lipid were recalculated on dry weight basis. Ash content varied from 0.81 to 1.01% with highest value observed in product obtained from wholesaler and retailer and lowest values in product obtained from producer. Lower levels of protein and lipid content in the products obtained from retailers and wholesalers were probably related to the losses occurring at different stages of marketing chain during handling, transportation and preservation. It was found that TVB-N value was 1.12 mg/100g in products obtained from producer whereas that value increased with the increase of intermediaries in the value chain. TVB-N value in product obtained from retailer was 3.12mg/100g although the values which were within the acceptable limit as suggested for fishery product.
Abstract: The study was conducted to evaluate the influence of formalin on the quality changes in rohu fish
(Labeo rohita, Hamilton) during ice storage condition. There are complaints from the consumers that the fish
traders in Bangladesh use formalin in fish imported from neighboring countries to increase the shelf life. On
the basis of organoleptic characteristics, the formalin treated fishes were found in acceptable condition for 28
to 32 days in ice as compared to the control fish, which showed shelf life of 20 to 23 days. B acterial load in
formalin treated fish was below detection level even after 16 days of ice storage whereas bacterial load was
significantly higher in fresh rohu stored in ice and at the end of 24 days of ice storage. NPN content was
increased gradually in fresh rohu with the increased storage period in ice. On the other hand, NPN content of
formalin treated rohu decreased gradually during the same period of storage. Protein solubility in formalin
treated fish decreased significantly to 25% from initial of 58% during 24 days of ice storage as compared to
40% from initial of 86.70% for control fish during the same ice storage period. Gel forming ability of formalin
treated fish was reduced significantly due to denaturation of muscle protein indicating poor eating quality and
poor digestibility of fish contaminated with formalin.
Abstract: Information was collected from fish retailers and consumers on the marketing of formalin treated fishes through survey using prescribed questionnaire in local markets of Bangladesh Agricultural University (KR), Kewatkhali Market (KM), Mecchua Bazar Market (MB), Natun Bazar (NB) and Sankipara Market (SP) located at Mymensingh town in Mymensingh district. The major species selling in the market were rohu (Labeo rohita), catla (Catla catla), hilsa (Tenualosa ilisha), sarputi (Puntius sarana), rajputi (Barbodes gonionotus) tilapia (Tilapia mossumbica), pangas (Pangasius hypophthalmus) and small indigenous species (SIS). It was found that many commercially important fishes such as catla and rohu were imported from neighboring countries and sold in the retail markets. There were complaints from the consumers that the fish traders use formalin in imported fish to enhance their shelf life which were denied by the wholesalers and retailers. Fish were, therefore, collected from different markets and formalin detection kit was used to detect formalin contamination in fish. Study showed that formalin was not detected in any fish produced locally, but was detected in the imported ones of catla and rohu ranging from 0.5% to 1% which was sold in different markets of Mymensingh with comparatively lower price than those produced locally. The shelf life of the locally produced fish was much longer than those of imported fish which may be related to the loss of shelf life during its transport from importing countries. The survey also indicated that the overall hygienic condition of the retailers and sanitary conditions of surveyed markets were poor except KR and SP fish markets, where both sanitary and hygiene conditions were found to be in acceptable condition.
Abstract: Studies were conducted to investigate the quality problems in giant tiger (Penaeus monodon) and giant freshwater (Macrobrachium rosenbergii) prawn at different stages of value chain in Bangladesh. Thirty nine P. monodon farms and 20 M. rosenbergii farms located in Coxâs Bazar, Bagerhat, Satkhira, Khulna and Mymensingh were visited and information were collected using prescribed questionnaires from cross-section of people working at farms, depot level and processing industries. The major aspects of information collected were: farm size; water source; culture type; source and size of PL; stocking density; feed and frequency of feeding; harvesting; farm production; post-harvest care; handling and transportation; infrastructure facilities; condition of shrimp during receiving at farm and depot level. Overall major problems of quality deterioration in shrimp value chain were use of unclean pond water for washing, longer duration of harvesting, exposure of shrimp at high ambient temperature (delayed icing), contamination, lack of general hygiene, lack of personal hygiene, excess water in shrimp, packed under pressure, piled up shrimp on a dirty floor, body crushed due to heavy pressure, rough handling, use of dirty utensils, contamination with flies and insects at depot level, resulting in considerable loss of shrimp quality.
Abstract: The stability of dark and white muscle protein of frozen stored fresh hilsa shad (Tanualosa ilisha) was evaluated by determining Ca2+ ATPase activity and inactivation rate constant (KD). The effect of temperature and pH was also studied. With the influence of temperature it was found that Ca+2 ATPase activities in both dark and white muscles declined slowly with lapse of storage period and dark muscle myofibrils were more heat stable than the white muscle myofibrils. pH also affected their stability where white muscle myofibrils denatured more quickly at acidic and alkaline pH range and with longer frozen storage period. The initial denaturation constant in hilsa shad dark and white muscle myofibrils increased sharply after 88 days of frozen storage, and the values of KD were characteristic for a typical tropical fish.
Abstract: Genet structure of an ectomycorrhizal (ECM) fungus Laccaria laccata was studied during a fruiting season and 9 months after the fruiting season in the volcanic desert on Mount Fuji. Below-ground samples of L. laccata were analyzed using SSR (microsatellite) markers. During fruiting season, most of the below-ground genets were identical to sporocarp genets of each sampling plot. In contrast, nine months after the sporocarp formation, many small genets were observed in each plot but previous year's sporocarp genet was not detected in 60% plots. Majority of new genets shared at least one common allele with the previous year's sporocarp in every SSR locus. This indicates, genets of L. laccata tend to disappear after sporocarp formation (within few months) and new offspring genets are generated from the spores disappeared from the sporocarp to the vicinity. The size and number of genet were significantly smaller and more in 'after fruiting season'. This result suggests, most of the newly generated genets disappear through competition with a sporocarp-producing genet that becomes dominant in the 'fruiting season'.
