Advances in Aquaculture and Fisheries Management

Advances in Aquaculture and Fisheries Management Vol. 1 (8), pp. 082-089, November, 2013. © International Scholars Journals

Full Length Research Paper

The study of the effects of smoked fish, horse mackerel (Trachurus trachurus) by different methods and storage at room temperature

Monjurul Xafri, Chakra Arafat and Saminul Farzana

Aquatic Biodiversity Laboratory, Department of Fisheries, Faculty of Agriculture, University of Rajshahi, Rajshah-6205, Bangladesh. E-mail: [email protected]

Accepted 31 October, 2013

Abstract 

The present study assessed the effect of hot smoke using wood and charcoal dry heat on keeping quality of Trachurus trachurus fish fillet, skin, head and bones (SHB). T. trachurus was smoked using the altona kiln at 80 to 105°C for eight hours, placed in cain woven baskets to cool off, packaged in sealed transparent polythene bags and left on shelf for 7 days at ambient temperature (32 ± 2°C). Biochemical indexes assayed were: pH, total volatile nitrogen (TVBN), peroxide value (PV) and total viable count (TVC). pH of raw T. trachurus fillet was 6.85 ± 0.00 but significantly reduced with wood smoke at day 0 to 6.70 ± 0.02, while TVBN in raw T. trachurus fillet was 27.17 ± 1.61 mgN/100 g. After smoking, TVBN of T. trachurus fillet at day 0 was 21.83 ± 0.38 mgN/100 g (wood) and 23.05 ± 1.36 mgN/100 g (charcoal). pH of raw T. Trachurus SHB was 5.87 ± 0.03 and increased (p<0.05) with smoking, that is, 6.43 ± 0.21 (wood) and 6.43 ± 0.00 (charcoal). TVBN in the raw T. Trachurus SHB was 28.12 ± 2.17 mgN/100 g, and after smoking on day 0, it was 31.90 ± 0.3 mgN/100 g (wood smoked) and 24.44 ± 1.90 mgN/100 g (coal smoked). The PV was highest in charcoal smoked SHB (CSHB) of T. trachurus at day 5 (108.40±36.80) and TVC was highest in the CSHB on day 5 (3.48 logcfu/g). The overall study showed that T. trachurus fish samples (fillet and SHB) prepared via charcoal smoking method had the lowest (p<0.05) storage time amongst the smoked fish samples, when compared with those that were processed via wood smoke.

Key words: Trachurus trachurus, ambient temperature, smoked fish and seafood quality.

Advances in Aquaculture and Fisheries Management Vol. 1 (7), pp. 070-075, October, 2013. © International Scholars Journals

Full Length Research Paper

Feeding and Feeding habits of three main fish species in Lake Baringo, Kenya

Brayant  Musyoka, Bochabery O. and Ajwang Amobi*

Department of Fish economics and management, Faculty of Agriculture, University of Nairobi, Nairobi, Kenya. Email: [email protected]

Accepted 27 September, 2013

Abstract 

The diets of three fish species of commercial importance in Lake Baringo, Protopterus aethiopicus, Clarias gariepinus and Oreochromis niloticus, were determined using frequency of occurrence and volumetric methods between April 2008 and March 2010. Seine and gill nets were used to catch a total of 430 fish specimens. The diet of P. aethiopicus was 94.3% molluscs with a frequency of occurrence of 98.6% of stomachs with food. Adult C. gariepinus fed mainly on fish with 75% of the stomachs with food containing fish remains and mean of 49.2% contribution by volume. C. gariepinus also fed on zooplankton, especially the cladoceran Daphnia barbata. The food items in the stomachs of O. niloticus consisted mainly of algae, detritus and zooplankton. Algae was consumed by O. niloticus of all length classes in proportions ranging from 26.5 to 88.1%. The importance of zooplankton as food for O. niloticus decreased with size of fish. The study reveals the importance of zooplankton as food for O. niloticus and C. gariepinus in Lake Baringo. There is need to rehabilitate the catchment of Lake Baringo so as to improve the water quality thus improve productivity.

Key words: Diet, Omnivorous, Algae, zooplankton, food web.

Advances in Aquaculture and Fisheries Management Vol. 1 (8), pp. 076-081, November, 2013. © International Scholars Journals

Full Length Research Paper

The Diet composition, sensory assessment and microbiological studies of fish cake made from shrimp bycatch

Nathaniel Chinedu, chika I. K and Nathaniel Oboroh Ameachi

African Regional Aquaculture Centre/Nigerian Institute for Oceanography and Marine Research, P.M.B 5122, Port-Harcourt, Nigeria. E-mail: [email protected]

Accepted 02 October, 2013

Abtsract 

This study reports on the nutritional composition, sensory evaluation and microbiological studies of fish cake made from shrimp bycatch. The yield of mince from the bycatch was 80.26% mince; 10.21% residue and 9.53% loss. The mince proximate composition was 66.32% moisture; 20.08% protein; 3.45% lipid and 3.93% ash. The proximate composition of the raw fish cakes was 64.40% moisture; 19.13% protein; 4.14% lipid; 6.11% ash and 6.22% carbohydrate. The deep fried fish cake had 60.12% moisture; 21.01% protein; 8.50% lipid; 6.30% ash and 4.07% carbohydrate. No significant difference (P > 0.05) was observed between the proximate composition of raw and deep fried fish cake. The peroxide values (PV) of raw and deep fried fish cake ranged from 7.20 - 22.00 mEqO₂/Kg of lipid during six week storage period. There was significant correlation between storage time and peroxide values in both treatments. Microbiological analysis showed that the Total Viable Count (TVC) decreased with increase in frozen period. The results obtained were within the acceptable limit of International Commission on Microbiological Specification for Food. The organoleptic properties of the deep fried cake indicated that the product was acceptable until about the fourth week. The study showed that fish cake from shrimp bycatch is microbiologically safe and nutritionally high in protein, fat as well as calcium.

Key words: Bycatch, fishcake, shrimp, sensory, proximate, mince, peroxide values, staphylococcus.

Advances in Aquaculture and Fisheries Management Vol. 1 (7), pp. 065-069, October, 2013. © International Scholars Journals

Full Length Research Paper

Time on nutritional parameters, physical quality and Smoke-drying temperature effect on Tilapia (Oreochromis niloticus)

Ojih Samson, Bello Edeh and Adeyeye Gbagi

Chemistry Advance Laboratory, Sheda Science and Technology Complex, P. M. B. 186, Garki, Abuja FCT, Nigeria.Email: [email protected]      

Accepted 03 September, 2013

Abstract

Effects of smoke-drying temperatures and duration of drying on the quality of Nile tilapia (Oreochromis niloticus) samples were investigated by smoke–drying Tilapia fish under three different temperatures (50, 60 and 70°C) and three drying times (5, 10 and 15 h) using modified drum kiln dryer. The proximate compositions of the fresh and dried fish were evaluated and the sensory evaluation of the organoleptic parameters was assessed. The drying temperatures and duration of drying have different effects on the quality of the smoke-dried fish. The moisture contents of the samples were reduced from the initial value of 75.11% to average safe storage values of 15.30 and 17.95% after smoke-drying at 60°C for 15 h and at 70°C for 10 h, respectively. The results showed that the crude protein, crude fibre, crude lipid and ash contents of the dried fish generally increased from the initial values as the moisture content decreased. It can be concluded from the results of this study that the best smoked fish with good quality parameters in terms of nutrient and organoleptic parameters were the products dried at 60°C for 15 h and 70°C for 10 h.

Key words: Fish, smoke-drying, drying temperatures, drying time, proximate composition, organoleptic parameters.

Advances in Aquaculture and Fisheries Management Vol. 1 (6), pp. 060-064, September, 2013. © International Scholars Journals

Full Length Research Paper

Categorization and Extraction of chitin; a functional biopolymer derived from scales of common carp fish (Cyprinus carpio l.): A stress free source

George Davison, Victor Sebastian and Lebechi

Aquaculture Division, Nigerian Institute for Oceanography and Marine Research, P.M.B. 12729, Victoria Island, Lagos, Nigeria. Email:[email protected]      

Accepted 23 August, 2013

Abstract 

Chitin is the most abundant natural amino polysaccharide and is estimated to be produced annually almost as much as cellulose. It has become of great interest not only as an industrialized resource, but also as a new functional material of high potential in various fields. Chitin was successfully extracted from the scales of a common Carp fish and characterized for it functional properties. Structural data of the chitin was determined by FT-IR and the crystalline and surface morphology were also studied by Powder X-Ray diffractometry and scanning electron microscopy (SEM). The proximate analysis determined was 2.12% moisture content, 1.56% ash and 4.18% Nitrogen. The amount of Ca, Mg, Zn, Fe, Cu and Mn present in the chitin was 26.84, 50.49, 21.80, 12.68, 0.22 and 1.17 mg/kg, obtained by atomic absorption spectrometry, respectively.

Key word: Chitin, chitosan, biodegradable, biocompatibility, non-toxic, X-ray diffractormeter, scanning electron microscope (SEM), fourier transform infrared (FTIR).

Advances in Aquaculture and Fisheries Management Vol. 1 (6), pp. 058-059, September, 2013. © International Scholars Journals

Short Communication

Features of weighty metals in canned tuna fish

Manindar Kumar, Tanmay Lakshya and Raaz Viraj

Department of Zoology, Fish Biology and Fishery Sciences, Gauhati University, Guwahati 781014, Assam, India. E. mail: [email protected]

Accepted 14 August, 2013

Abstract 

Concentrations of metals (aluminium, cadmium, lead and mercury) were determined from canned tuna commercialized in Canada and India, by inductively coupled plasma - optical emission spectrometer (ICP-OES) and direct mercury analyzer (DMA 80). Higher concentration of Al (1.806 to 3.161 µg/g) and Hg (0.60 to 0.62 µg/g) were found in tuna processed from India. Cd and Pb ranged from 0.020 to 0.025 and 0.011 to 0.089 µg/g respectively in Canadian canned tuna. Among metals, Cd showed lower values in both samples. In conclusion, highest levels of metals were accumulated in Indian made product. This can be attributed to differences in the canning process and quality of food. It was concluded that heavy metals in canned tuna must be monitored comprehensively and periodically with respect to the consumer health.

Key words: Canned tuna, heavy metals, inductively coupled plasma - optical emission spectrometer (ICP-OES), seafood.