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Fresh catfish (Clarias gariepinus) is highly perishable. This paper aims to investigate the drying characteristics and quality of body-mass dehydrated catfish to determine the effective dehydration parameters for preservation.

Brine concentration (3-9 per cent), brining time (30-90 min) and drying temperature (90-130°C) interacted using the response surface methodology. Preliminary experiments were conducted to select treatments. Moisture content and ratio and drying rate were determined and fitted into five thin-layer drying models; the goodness of fit was evaluated by average grade ranking of the regression parameters. Proximate compositions and microbial load of dehydrated catfish were determined using standard methods.

Treatments with 110°C gave initial higher drying rate (0.034-0.043 kg H₂O/kg solid/h) and shorter drying time (20-21 h). Drying occurred at two falling rate periods. Midilli model ranked first in fitting the drying data. It explained up to 99.6-99.7 per cent of the total variations in the independent variables with low values of error terms; RMSE was 0.02131-0.01794 and χ² was 0.00037-0.00043, indicating good predictive quality. Processing parameters positively and significantly (p < 0.05) influenced the proximate compositions of dehydrated catfish. Treatment: 6 per cent brine, 90 min and 110°C presented the most effective dehydration parameters for quality preservation of body-mass catfish.

The dehydration technique used in this study could enhance nutritive quality and storage stability of body-mass dehydrated catfish that could serve as a useful and convenient tool for commercial application.

Hygienically processed dehydrated catfish of good quality could be used as a source of nutrients to ameliorate malnutrition and reduce post-harvest losses of catfish.

The effective processing parameters established is an important step to harness the high nutrients and economic values embedded in catfish.

Fishes are important sources of good and high-quality protein in developing countries. Spoilage and keeping quality of fish especially in the tropics is temperature dependence as high temperature and relative humidity accelerate the process of spoilage and fish keeping quality. Fish dehydration removed moisture and extended the shelf life of dried fish. Drying involves removal of moisture from fish as a result of heat and mass transfer done under controlled conditions. This study delves into various drying techniques and drying kinetics of fish.

The review examines fish drying kinetics and the various drying models applicable to fish drying.

This review showed that moisture content and colour of dried fish are affected by time and power level. It was also found that the moisture content of the dried fish varied according to the drying method used. Also, as drying power and drying rate varied inversely with drying time. Eight different thin layer drying models were examined for evaluation of drying data for all the experimental conditions involving fish drying. It was found that the quality of the dried fish decreased with drying. Higher values of effective moisture diffusivity have been found to increase moisture velocity within fish samples which improve removal of moisture to reach equilibrium moisture content at specified relative humidity. However, based on this, effective moisture diffusivity could be a useful parameter to design an effective drying method in terms of time, energy consumption and cost to prolong the storage life of dried fish samples. Drying kinetics and different drying models were considered and explained. The use of these models was considered to be important in choosing appropriate drying conditions for effective drying and to get good quality dried fish samples.

The review considers few available literatures on the subject matter.

The review explores the possibility of creating more awareness for more in-depth research on fish drying kinetics and their usefulness in fish preservation.

This outcome of this study is important to researchers, policymakers and regulatory agencies in developing countries on fish preservation.

For thirty years or so the Middlesex County Council, through its Public Control Department, has persistently tried to protect purchasers of fish from malpractices in the retail fish trade. It would be incorrect to suggest that no other Food and Drugs Authority has tried to do the same, but it is evident that in many areas there has been little or no overt sign of similar activity. Recently there was a Middlesex prosecution in which the owners of a restaurant were fined £2, with £4 costs, for supplying fried dabs described on the menu as plaice. This aroused the ire of a Mr. Ralph A. Hadrill, who wrote to The Times a letter severely criticising the Council. To that letter pride of place on the leader page was given by the Editor of The Times. Two days later, four further letters were printed on this intriguing subject. One writer expressed the view that some purchasers prefer dabs to plaice in the spring. The Chairman of the Middlesex General Purposes Committee strongly criticised Mr. Hadrill, and emphatically denied that his Council was wasting the ratepayers' money. On the contrary, he claimed that the Council provides purchasers of fish with very necessary protection at a most economical cost.

This study aims to assess the quality and microbial safety of traditional smoked spotted tilapia fish from Lagos State and, by doing so, determine the quality and microbial safety level of traditional smoked spotted tilapia fish, their distribution, effects and possible public health implications of the quality/rancidity indices and microorganisms on the consumers.

Fresh spotted tilapia fish (100 samples) were collected from 20 different fishing/processing centres and divided into two batches. One batch was smoked with local drum kiln at processing centres, and the second batch was smoked with convective smoking kiln as control in the laboratory. Each batch was assessed for moisture content, protein content, fat content, crude fibre content, ash content, pH, thiobarbituric acid (TBA), total volatile base- nitrogen (TVB-N), trimethylamine (TMA), peroxide value (PV) and free fatty acid (FFA) values. Microbiological analyses were also conducted. Each batch was assessed for total viable count (TVC), fungal count, Listeria monocytogenes count, Staphylococcus aureus count, Salmonella paratyphi count and presence or absence of Escherichia coli.

The results of the proximate composition, quality indices and microbiological analyses revealed that there was significant variations (p < 0.05) between smoked fish with different smoking methods. The mean pH, TBA, TVB-N, TMA, PV and FFA values of fresh and smoked spotted tilapia fish samples were within the range recommended by United States Food and Drug Administration. The mean TVC of fresh spotted tilapia fish samples was 6.3 × 106-8.8 × 108 cfu/g and TVC of samples of smoked spotted tilapia fish and the control were 2.0 × 104-6.4 × 104 cfu/g and 1.0 × 103-8.6 × 103 cfu/g, respectively. The mean L. monocytogenes count of fresh spotted tilapia fish samples was 1.3 × 102-2.4 × 102 cfu/g and that of samples of smoked spotted tilapia fish ranged from 1.6 × 101 to 23.1 × 101 cfu/g while samples of smoked spotted tilapia fish using convective smoking kiln showed no count for L. monocytogenes. The mean S. aureus count of fresh spotted tilapia fish samples ranged from 4.7 × 103 to 8.0 × 103 cfu/g and that of samples of smoked spotted tilapia fish ranged from 5.1 × 102 to 88.6 × 102 cfu/g and 1.1 × 102 to 3.8 × 102 cfu/g. The mean fat content (FC) count of samples of smoked spotted tilapia fish ranged from 1.1 × 101 to 6.0 × 101 cfu/g. S. paratyphi and E. coli were not detected in all smoked spotted tilapia fish samples. The study, however, concluded that the traditional drum smoked spotted tilapia fish could expose consumers to high microbial risk because of the presence of L. monocytogenes.

The fresh fish used in this study were obtained from coastal villages in Lagos State, and there were limitations in getting the samples in time to the processing centres and in preserving the fresh fish because of poor or non-availability of power (electricity).

The paper includes implications for the development of a cost-effective smoked fish, to ensure food safety, enhanced health and improve the preservation and post-harvest losses of fresh fish.

The paper helps in developing an effective smoked method that will produce good-quality smoked fish, reduce the incidence of food poison and enhance the health of consumers.

This research is of value to the traditional fish smokers and consumers. Smoked fish has been implicated as a source of microbial infection in Nigeria and West African sub-region in recent times and the need for good manufacturing practices cannot be overemphasized.

This new measure of consumer law of some forty‐odd sections, a short Act by present standards but as far‐reaching as any legislation since the war, establishes a code of conduct in commerce and trade which few will be able to ignore, from the manufacturer down to the counter‐hand. Operative from November 30th of this year, traders will require to urgently consider their sales practices, advertising, labelling and their trade descriptions; sales staff will need to be instructed in their new responsibilities. The new law is not just for consumer‐retailer transactions, but extends to trade between different branches of all trades, so that a retailer will be protected against misleading descriptions and misrepresentations by a manufacturer and the latter against misdescriptions of ingredients or components.

This paper aims to take a critical review of traditional fish processing in Nigeria.

A critical review of traditional fish processing in Nigeria was undertaken.

Fish is one of the protein foods that need careful handling. Due to poor handling, about 30-50 per cent of fish harvested are wasted in Nigeria. This study was therefore carried out to review fish processing technologies and evaluate the effectiveness, energy sources and efficiency of fish processing equipment used, quality and safety of processed fish products and possible improvement. Studies revealed that the fish when brought aboard is usually more or less alive, stored simply on the bottom of the canoe and lying there in a pool of warm, dirty water. The fish is never gutted and freely exposed to the sun, and better handling practices would help in developing a fresh fish export trade toward the larger towns in the north and south. Several studies revealed that fish smoking still remains the main method of fish preservation in Nigeria as over 70 per cent of the catch is smoked. The quality of smoked fish from Nigeria has been found to be within acceptable quality limits specific by various regulatory agencies. However, findings have revealed microbial contamination and the presence of polycyclic aromatic hydrocarbons in some of the smoked fish which values exceed the EU recommended maximum permissible level of 5.0 μg/kg for benzo[α]pyrene.

Few available literatures on the subject matter were critically reviewed.

The paper helps in creating opportunities for more in-depth research in fish processing in Nigeria.

This research is of value to the researchers in Nigeria and other tropical countries.

This paper aims to assess the efficiency of emulsified essential oils in glycerol as eco-friendly antimicrobial and plasticized agents added to the biopolymer of gelatin for lining historical oil paintings on canvases.

Cedar oil, cinnamon oil and their mixtures were emulsified in glycerol and incorporated into gelatin adhesive as green biocides and plasticizers. Physical, biological, chemical and mechanical tests were conducted on experimental mock-ups to assess the gelatin-based adhesive formulations for the reinforcement of canvas supports. Scanning electron microscope, colorimetric measurements, antimicrobial activity test, attenuated total reflection-Fourier transform infrared spectroscopy, tensile strength and elongation tests were carried out on the mock-ups before and after the artificial aging.

The formulations of gelatin-based adhesive with cinnamon and cinnamon-cedar mixture emulsified in glycerol proved their efficiency on the antimicrobial activity test, chemically delaying the decomposition of gelatin and accordingly providing compatible mechanical properties. Gelatin-based adhesive with emulsified cinnamon oil showed a slight yellowing that was quite improved with the mixture of the cinnamon-cedar-based adhesive formulation.

This study promotes a green approach to lining historical oil paintings by developing green formulations from bio-based origins that minimize the shrinkage and microbial infection of gelatin for lining paintings.

The purpose of this paper is to produce fish nugget from fresh or smoked fish and to investigate the quality characteristics of fish nuggets during refrigerated storage.

The study was designed to evaluate the effect of fresh and smoked fish on the storage quality parameters of fish nuggets. The products were developed by incorporating optimum level of fresh and smoked separately and were vacuum packaged in low-density polyethylene pouches and assessed for various storage quality parameters under refrigerated (2±1°C) conditions for 27 days of storage. The products were evaluated for various chemical, microbiological and sensory parameters at regular interval of three day.

Nuggets from smoked fish had lower (p<0.05) moisture, higher fat and crude protein compared to fresh fish nuggets. Total volatile basic nitrogen for fresh nugget samples exceeded the limit value of 30 mg N/100 g fish muscle on the 24 days of storage. At the end of storage period, TBA values were 2.8 mg malonaldehyde/kg for fresh nugget samples and 2.1 mg malonaldehyde/kg for smoked nugget samples. Microbial counts were found to be significantly (p<0.05) higher in fresh nugget than in smoked nugget samples. Sensory quality scores of smoked nuggets were significantly higher, than fresh nugget. The shelf life of fish nugget was found to be 24 days for fresh nuggets and 27 days for smoked nugget samples according to sensory assessment results.

The paper has demonstrated that the smoked fish meat prouduce nuggets of better quality, as indicated by lower microbial counts and higher sensory attributes compared to fresh fish meat.