Field testing of methodologies for evaluating post-harvest losses in the artisanal fisheries of Dorobaga fishing community and Baga fish market in Maiduguri

by

G.R. Akande
Nigerian Institute for Oceanography and Marine Research,
Wilmot Point Road, Bar-Beach,
Victoria Island, Lagos, Nigeria

and

D. Odogbo
Federal Department of Fisheries, Federal Ministry of
Agriculture, Water Resources and Rural Development,
Maiduguri, Borno State, Nigeria

1. INTRODUCTION

Lake Chad, where this study was carried out is located on longitude 14⁰ North and latitude 13⁰ East in Borno State and shared by four West African countries: Chad, Nigeria, Niger and Cameroon. The lake lies within the high tropical regions of extreme scorching heat, where temperatures in the shade can reach 45-49⁰C. There are about 200 permanent and semi- permanent fishing communities/islands and over 40 000 fishermen on the Nigerian sector of the lake. Lake Chad remains the leading producer of freshwater fish amongst all the Inland waters of Nigeria. Predominant fish species include Clarias, Tilapia, Gymnarchus, Heterotis, Lates niloticus, Protopterus, Alestes, Synodontis, Citharius etc.

Between 1990 and 1994 the inland fisheries contributed an average of 38.6% and 34.4% to the total artisanal and national fish production respectively. Between 1985 and 1994 fish landings from the Nigerian sector of the lake amounted to 481 657 metric tonnes, representing 18.42% of the total domestic fish landings in the Country (FDF, 1994).

Despite the socio-economic importance of the lake in terms of employment generation and the supply of scarce fish proteins to the people of Nigeria, insufficient attention has been paid to the rational exploitation and sustainable management of its resources. Better management strategies to enhance fish production should include better handling and processing methods of what is presently caught. This will in turn minimise post-harvest losses of fish and fishery products (usually quoted at levels between 35 and 40%) and also encourage compliance with the Inland Fisheries Decree of 1992 which provides guidelines for responsible fishing in Lakes and reservoirs.

The magnitude of the various types of losses that occur between capture and consumption is difficult to measure for several reasons:

- little effort had been made to develop systematic and practical assessment methodologies that can generate accurate information in post-harvest fish losses.

- much of the historical data available on post-harvest fish losses, especially loss levels is derived from limited and unsystematic observations and studies.

- in many cases, the type of loss being measured and the way that data have been collected and interpreted is not clear.

The figures quoted for Nigeria range from 30-40 percent and specifically, the estimates and measurements for Lake Chad fisheries range from 22-56 percent for dried unsalted fish (Mills, 1979, Moes, 1980).

This purpose of the research is to test the three methods (PRA and Load Tracking and Questionnaire) for assessing fish losses in Dorobaga fishing community and Baga fish market, Maiduguri, Borno State, Nigeria. It was made possible by a joint research project between the West African Association for the Development of Artisanal Fisheries (WADAF) and the Natural Resources Institute (NRI).

2. METHODOLOGIES

Two of the three methods were field tested, the Participatory Rapid Appraisal (PRA) and the Load Tracking methods. The methods are designed to:

* generate background information on post-harvest fisheries losses
* clarify the flow of fish and fishery products.
* quantify losses in the chain
* establish reasons for losses
* identify options for loss reduction

Table 1: Checklist for PRA studies of the economic operators in fish, processing and marketing.

2.1 Participatory Rapid Appraisal (PRA)

For the PRA method, the checklist in Table 1 was used to guide the interviews and discussion with fishermen, fish mongers, processors, traders and transporters. Interviews focussed mainly on general information about the sector; activities carried out by each of the economic operators, losses occurring and interventions to address them. For the various topics and sub-topics in the checklist, the following tools were selected:

Secondary sources of background information of the extent of losses in the past, the fisheries of the area, government interventions in the past and other key issues and problems were used. Information was also collected from State and Federal Department of Fisheries in Maiduguri, Borno State, from papers in learned journals, books and reports.

Semi-structured interviews were carried out with a total of 45 fishermen in three villages, 20 fish processors and 30 fish traders/transporters. Some key informants were also interviewed. The information from these interviews formed the core results of the PRA.

Direct observations were critical in cross-checking data obtained through interviews. A direct observation checklist was completed by one team-member during the group interview. It included a section on the condition and quality of fish at the different stages of catching, handling, processing and distribution which was important in analysing where losses may be occurring.

Ranking and Scoring were non-diagrammatic methods introduced to the economic operators during the fieldwork to explore the group's perceptions and preferences as regards important fish species caught in the lake, fishing gear used, prices and the degree of post-harvest losses vis-à-vis the species studied.

2.2 Load tracking

Merit scoring

Smoked catfish, Clarias gariepinus were purchased from fish dealer in Baga smoked fish market, Maiduguri. The smoked fish were given merit scores (Table 1) based on some external features such as colour, dryness and physical state of the product. Other criteria used included burning, skin condition, mould growth and taste. The economic operators generally use the degree of dryness, colour and physical state of the smoked fish as traditional indicators of quality.

Packaging of smoked catfish

Smoked catfish were packaged in cartons normally referred to as "Lagos cartons" because they are made from used tobacco cartons imported into the country and are usually purchased from Lagos, Kano, and Port Harcourt. The choice of packaging material was informed based on the PRA which shows that this is the type of carton that takes fish to Lagos as opposed to Mondula and Rothmas which are used for Onitsha and Enugu respectively.

Transportation of smoked catfish

Table 2: Merit score sheet for smoked catfish, Clarias gariepinus.

Transportation of smoked fish was by arrangement with transporter plying Maiduguri to Lagos. The cartons were loaded and transported to Lagos in a 911 Mercedes Benz lorry. The journey from Maiduguri to Onipanu in Lagos market where the coordinator was waiting to receive the fish took 72 hours, covering a total of approximately 1,000 km. The road is generally good; the driver usually encounters few potholes on the road. The distance between Onipanu warehouse and NIOMR Headquarter where the fish was subjected to analysis is about 15-20 km, although smooth surface road, some parts were also bumpy and pot holed.

Load tracking exercise

Five cartons of smoked catfish were graded before load tracking at Maiduguri based on the merit-scoring sheet in Table 2. From each carton containing on the average 10 kg of fish, samples representing 10% of the total were selected at random. The samples were tagged using white strings and the quality assessed on a scale of 0=bad or poor quality, 1= average or fairly good quality and 2=good quality fish (this is the reverse of traditional demerit scoring where the best quality is given a 0 score, in Nigeria giving a score 0 usually denotes poor quality, while higher numbers indicate better grade or preference).

After transportation to Onipanu warehouse in Lagos, all the cartons containing the smoked fish were off-loaded following the normal procedure and then transported to NIOMR laboratory for analysis. The same sets of tagged fish were again quality evaluated based on the merit-scoring sheet used for smoked fish before transportation. After merit scoring of the tagged fish, the rest of the contents of each carton was subjected to the same merit scoring parameters. The number of pieces in each carton, weight in kg and percentages of the parameters vis-à-vis the original quantity of fish were recorded and the physical, qualitative and economic losses were calculated.

3. RESULTS AND DISCUSSION

3.1 Perceptions of the methods by researchers and economic operators

An interesting finding in this study is the fact that fishermen, while admitting losses in their daily operations do not seem to think that such losses significantly affect their income generation adversely. To a fisherman, fish loss is not high on his priority list (Table 2) rather inadequacy of fishing inputs especially outboard engines and nets were considered as more significant constraints. If there is a ready supply of fishing inputs to assist in catching more fish physical and quality losses are apparently accepted as normal operational losses. Although the use of ice may not be within the fishermen's easy reach, other means of ensuring that losses are minimised have been devised and include the use of wet grasses, leaves and sacks placed on the fish as protection against scorching sum.

Table 2: Ranking of major constraints by a fisherman

Table 3: Ranking of major constraints by fish processors.

Table 4: Ranking of major constraints of smoked fish marketers.

Table 5: Ranking of the different causes of post-harvest losses in the market.

The fish processors and marketers similarly to the fishermen rated losses due to insect infestation lower to those resulting from poor and unreliable transport system and market environment (Tables 3 and 4). Although this was also the case in Iddo/Onipanu markets in Lagos, the economic operators here placed greater emphasis on market forces (Table 5) as major factor for the economic losses recorded by them. To the fish processors, the use of chemicals in the preservation of their smoked fish received the lowest rating. It is odd that this was reported given the observation made in the widespread use of insecticides in spite of prohibition by the Government, against insect attack at all steps of processing, unmindful of the toxicity hazard to consumers.

In all the three sub-sectors of the artisanal fishery studied, it was found that the use of semi-structured interview as a tool of PRA did not extract information on the use of obnoxious methods in fishing and preservation from the economic operators. On the other hand, another tool; direct observation was more effective in this respect. Therefore, direct observation was more critical in cross-checking data obtained through interviews.

The only exceptions are the marketers in Iddo, Lagos who owned up to the use of chemical insecticides but were quick to point out that these chemicals are sprayed on the packaging material and not on the fish directly. Nevertheless, in both these cases, the need for raising the awareness of the operators is evidently manifested.

The PRA method used in this study was found to permit a quick and systematic collection of data, more adapted to providing socio-economic data than precise statistics on post-harvest fish losses of the communities. The method was particularly found to be useful in evaluating constraints and likely solutions to enable informed and timely decisions to be taken for reducing post-harvest losses. The method also enabled the research group to have a better understanding of the attitudes of the community, beliefs and behaviours towards harvesting, handling, processing, marketing of fish and their perception of loss assessment in each of the sub-sectors of the fishery.

The use of PRA in loss assessment is very effective, permitting one to obtain information from respondents at will and allowing full participation of individual economic operators. Another advantage of the method lies in the fact that groups as well as individuals are targeted. A disadvantage noted was that during the seasonal calendar exercise, there was the tendency for subsequent participants in the exercise to blindly reproduce the information given by the first respondent, possibly due to the effects of illiteracy, which is at a high level with the economic operators.

Losses registered using PRA method in Table 6 indicates average physical losses for fishing, processing and marketing were 10.83%, 6.56% and 4.19% respectively. Quality losses were 8.67%, 3.13% and 4.92% for fishing, processing and marketing respectively. Cumulative physical, quality and total loss in the sector are 21.58%, 16.72 and 38.30% respectively.

There are more physical losses when the entire fishery sector is taken into consideration. However, of the three sub-sectors, fishing accounts for more physical and quality losses implying that improved methods of harvesting and handling fish are needed in the sub-sector to reduce the high rate of loss.

Table 6: Summary of physical, qualitative and economic losses in fishing, processing and marketing

The PRA method no doubt registered quantitative losses in the fisheries of Lake Chad to be 38 per cent. However, the figure of 38 percent obtained in this study compares favourably with figures reported or quoted by other authors. The estimated and measured figures of Lake Chad fisheries range from 22-56 percent for dried unsalted fish (Osuji, 1977. Mills, 1979. Moes, 1980). Eyo and Mdaihli (1997) reported a total loss of about 50 per cent for the fisheries of Kainji Lake.

Table 7 summarises the losses encountered during load tracking exercise. Average physical and quality losses of 5 cartons each and load tracked twice from Maiduguri to Lagos were 1.90% and 8.04% respectively. This brings the cumulative total loss in the marketing sub-sector to 9.94%. Total loss in this sub-sector using PRA method was 9.11%, which shows good comparison between the two methods.

Given that this study focused on the marketing chain, it is necessary for the load tracking method to be tested in the fishing and processing chains for comparative analysis of results.

Table 7: Summary of losses encountered during load tracking exercise

With the load tracking method, it was possible to obtain quantitative and qualitative data on the losses incurred during handling and transportation of smoked fish. The method makes possible an objective assessment of the quality of the smoked fish and a systematic examination of all the variables in the distribution chain, which can influence quality. An important aspect of the method is its use of simple merit scoring for quick organoleptic assessment of fish quality in the field. The potential snag is to be found in the practice of tagging individual fish, which may lead to preferential handling and possibly exacerbate physical damage.

3.2 Constraints/problems of the economic operators and the intervention strategies

The methodologies tested provided first hand knowledge of the constraints and problems faced by the sector directly from the economic operators themselves. They listed solutions to these constraints and problems and the coping strategies presently used for limiting losses as well as those which are needed in future.

Fishermen's constraints

Heading the list of constraints most frequently mentioned was lack of inputs in form of nets and outboard engine (OBE). Constraints of infrastructures (cold stores, making plant, insulated containers etc) for storage of fish caught especially during bumper harvest. Also frequently mentioned is the constant conflict between the Chadian fishermen and their Nigerian counterparts over access and fishing rights on the Lake.

Interventions

Coping strategies presently used by fishermen to curtail fish losses include the use of wet leaves, grasses and sacks to provide shade for the fish from the scorching sun and flies. However, the under-listed are interventions that fishermen will wish be provided to boost their catch and reduce losses.

- Provision of nets and 40-50 H.P OBE to allow for speedy transportation from fishing island to landing sites on the shore of the lake.

- Provision of jetties, ice making plant and cold storage facilities. This will enable them to improve marketing of fresh fish and increase their incomes.

- Provision of insulated containers adapted to the size and shape of their boats.

Fish processors' constraints

- lack of quick means of transportation from landing to processing sites.

- lack of storage and processing facilities to absorb large quantities of fish especially during glut.

- shortage of firewood and expensive to buy

- insect infestation and flies.

- electricity to enable processing at night hours.

Interventions

Presently, fish processors curtail losses by;

- re-heating smoked fish that are infested with insects.

- merit scoring merit scoring storage of smoked fish not ready for market in locally constructed wire cages which allow free movement of air.

- perforation of cartons during storage to allow for air inside the carton.

Requested interventions by the fish processors include:

- provision of motorbikes to quicken transportation from landing sites to processing sites.

- infrastructure such as pre-fabricated houses to carry out processing to provide

- protection against adverse weather conditions.

- provision of standard smoking kiln preferably with cover because of sun and rain.

- provision of cold storage and ice making plant facilities to preserve their catch.

- chemicals to prevent flies and insect infestation pre-and- post processing of the fish.

- any technology that will replace the use of firewood but at the same time retain all the quality attributes associated with their smoked fish over the years.

Fish traders' constraints

- sanitary conditions of the market

- packaging materials

- insect infestation

- breakdown of vehicle on the road

- lack of regular orientation and visits by experts

- fish from processing sites not properly dried.

Intervention

The fish traders' coping strategies to curtail losses are based on the causes of such loss. For example engaging night watchmen minimises loss due to pilferage. When the moisture content of the fish is high, re-smoking is used and if the fish is mouldy, the moulds are scrubbed off. Insect infestation is prevented using salt and pepper, fragmentation is reduced by the use of oil and water to spray the fish and the menace of rodents is curtailed using baited traps and cats.

Outside their own intervention strategies the marketers would want the follow intervention strategies researched into or put in place to reduce post-harvest fish losses.

- generally clean environment with platforms to prevent the spreading of fish on mats on bare floors

- rigid boxes which are returnable and preferably made of plywood.

- chemicals to protect their products from insect infestation

- warehouses for storage of fish waiting to be evacuated for other marketing centers

- regular visits of insect expert and sanitary inspectors for awareness programme.

In summary, the constraints and problems can be grouped into three categories namely infrastructure, technical package and supplies. Under infrastructure, we have equipment, buildings, plants etc. For technical package, this will involve control of insect infestation, handling and processing for better-smoked products, sanitary condition of the market and storage facilities. The supplies will come in form of firewood for smoking and chemicals to control insect infestation.

4. CONCLUSION

The two methods tested on the field were effective in the assessment of post-harvest losses. PRA tools were advantageous in not only being able to assess losses but also provide other information, which can assist policy makers to plan for reducing these losses. The load tracking method, on the other hand, allows for a better understanding of the quality of fish as they pass through the different distribution chain. The two methods highlight losses in the distribution chain - fishing, processing and marketing as perceived by economic operators. The level of loss in percentage obtained in this study was less than the figures (estimated and determined) quoted by various authors.

It is recommended that further loss assessment work be carried out on a continuous basis for a reasonable length of time before a solid conclusion can be drawn on the extent of fish losses in the inland fisheries of Lake Chad.

5. REFERENCES

Ames, G.R. (1992). The kinds and levels of post-harvest losses in African inland fisheries. In: Proceedings of the symposium on post-harvest fish technology. FAO. CIFA Technical paper No. 19.

Eyo, A.A. and Mdaihli, M. (1997). Assessment of post harvest losses in Nigerian Fishery: The Kainji Lake Model. NIFFR/GTZ Kainji Lake Fisheries Promotion project, New Bussa, Nigeria.

Mills, A. (1979). Handling and processing fish on Lake Chad.

Moes, J.E. (1980). Nigeria. Reduction of spoilage of fish caught in Lake Chad. Project report NIR/74/001/F/01/12.

Osuji, F.N.C. (1977). The influence of traditional handling methods on the quality of processed fish in Nigeria. In: Conference proceedings handling, Processing and Marketing of Tropical Fish. TPI, United Kingdom.

Federal Department of Fisheries (1994). Fisheries Statistics of Nigeria. 3^rd Edition. Federal Department of Fisheries, Wuse Zone 1, Abuja FCT, Nigeria.

Application of load tracking in the distribution chain of smoked West African sardines Sardinella maderensis: a case study of Magbon-Alade fishing community, Lagos, Nigeria

by

Gbola R. Akande
Nigerian Institute for Oceanography and Marine Research
Wilmot Point Road, Victoria Island,
Lagos, Nigeria.

1. INTRODUCTION

The artisanal fisheries sub-sector in Nigeria plays a significant role in fish supply and employment generation, being the mainstay in terms of the contribution that fisheries makes to the economy. It contribution to of the total output of fish production is over 80 percent. Regrettably, however, as much as 40 percent of the total weight landed is reported to be lost due to poor post-harvest handling, preservation, processing, storage and distribution inadequacies. The most obvious means of increasing supply of fish, even without increased landings, is by reducing post-harvest losses of what is presently caught.

Post-harvest losses can be categorized into physical and economic terms. Physical losses are defined as fish that is thrown away or lost and not sold due mainly to quality deterioration. An economic loss is a loss in revenue due to selling fish for less than the best price attainable because of quality deterioration or market forces. To be able to curtail both the physical and economic losses in the artisanal fisheries, an assessment of these losses is primordial to enable one identify why and where losses occur thereby providing sound basis for advising economic operators in this sub-sector and policy makers in Government.

Post-harvest losses in small scale fisheries can be measured using three methods resulting from research work started in Tanzania by Natural Resources Institute (NRI) U.K and further developed through collaborative research between NRI's Post Harvest Fisheries Programme and WADAF''s West Africa Regional Programme Improvement of Post Harvest Utilization of Artisanal Fish Catches. The methods are (a) an informal method based on Participatory Rural Appraisal (PRA), (b) a formal Recall Questionnaire method and (c) Load Tracking.

The objective of this study is to field test the load tracking method for assessing losses in the distribution chain of smoked sardines Sardinella maderensis processed in Magbo-Alade, a fishing community located about 60 km East of Lagos metropolis.

2. MATERIALS AND METHODS

Fish samples

The species studied is the West African sardines Sardinella maderensis. The fish are usually landed on a sandy beach. The gears used in the catching operation included a beach seine and encircling nets. A typical trip usually starts around 6.00 a.m. and finishes (arrival time) around 2.00 p.m. Fish samples were purchased directly from the wives of the fishermen in measures of 200 pieces representing one hand.

Quality assessment of fresh sardinella

The quality of freshly caught sardinella was assessed using the merit score sheet. Because of the time lag between landing and actual smoking, the quality was again measured using the same merit score sheet, primarily to assess the effect of delay in smoking on the quality of the fish. The time and temperature profiles of the fish prior and during smoking were recorded. Ambient and fish temperatures were measured using Jenway 200 series electronic thermometer

Processing of sardinella

Un-gutted whole sardinella with scales on were washed using water from shallow well. The fish was washed to remove sand and other extraneous matter which the fish might have picked up as a result of the practice during landing of spreading the fish on bare sandy beach. After allowing the water to drain, the fish were laid on wood-supported wire mesh in a traditional rectangular mud oven. The fish were smoked-dried using hardwood for 48 hours by which time it was ready for transportation to the market. There were occasional turnings during the period of smoking to ensure uniformity in drying of the final product.

Merit score sheet for fresh sardines (Sardinella maderensis)

2.1 Load tracking

Merit scoring for smoked sardinella

The smoked Sardinella were evaluated by merit scoring.

Merit score sheet for smoked sardines (Sardinella maderensis)

Packaging of smoked sardinella

The smoked fish were packed in two baskets using the same method of the women processors. The top of the baskets was covered with polypropylene sack sewn to the sides of baskets. One of the baskets contained 300 pieces of smoked fish and the other 350 pieces. The weights of fish in the baskets were 20.5 kg and 22.5 kg respectively. The choice of packaging in two baskets was influenced by the loading pattern of smoked fish into commuter bus which is the mode of transportation. Baskets used in transporting smoked fish to the market vary from those that can only take between one and two hands. (i.e. 200 to 400 pieces of sardinella) and those large baskets that can hold between 5 and 10 hands (1 000 to 2 000 pieces of sardinella). The smaller size baskets were used in this particular experiment.

Transportation of smoked sardinella

Transportation of the smoked fish was by arrangements made with commercial bus used by the economic operators. The economic operator who participated in the study joined the bus. The fish was transported to Oju-Olobun smoked fish market in Central Lagos, where the co-ordinator was waiting to receive the fish. The journey from Magbon-Alade to Oju-Olobun market takes approximately one hour. The distance is 70 km. The road is good, although the last 5 km portion is rough and pot holed.

Load tracking exercise

Table 1: Merit scores for fresh Sardinella between landing and smoking of the fish

Two baskets of smoked Sardinella before and after load tracking were graded based on the merit-scoring sheet in Appendix II. From each basket containing 300 and 350 pieces 10% representative samples of the total lot in each basket were selected at random. The samples were tagged using masking tape around the tail and the quality assessed. on a scale of 0 = bad or poor quality, 1 = average quality and 2 = good quality fish. After transportation to the selected market, the contents of the basket were discharged following the normal procedure by the economic operators and the same set of tagged fish were again scored based on the merit scoring sheet used before transportation. After merit scoring of the tagged fish, the quality of rest of the contents of each basket was also assessed using the merit scoring parameters; the number of pieces in each basket, weight in kg and proportion of the different grades relative to original quality of the fish were registered and finally, the total or economic losses were calculated.

3. RESULTS AND DISCUSSION

Quality assessment of fresh sardinella

The results of the merit scores immediately after landing and just before the commencement of the smoking process are presented in Table 1. The results obtained based on the merit scoring scheme used in each case were similar, that is to say, a merit score of 2, indicating that the fish was of good quality fish at landing and prior to smoking. However, even though the merit score indicated identical quality levels, the quality of the latter must have been slightly inferior based on the appearance of the scales and the presence of slime on the fish. Ambient temperature recorded was 27°C while that of the fish was 26°C. The time from landing to smoking (the time fish was left unattended to) was found to be 4 hours. The price of fish after landing and before smoking was stable at N1400 per measure of 200 pieces.

Table 2: Merit scores for fresh Sardinella between landing and smoking of the fish

Load tracking of smoked sardinella

Table 3: Average merit score for smoked Sardinella immediately after smoking and after transportation to the market (Basket 2)

The merit scores for smoked Sardinella immediately after smoking and after transportation to market for baskets 1 and 2 are presented in Tables 1 and 2 respectively. Total score after smoking for basket No.1 was 11.6 while the score recorded after transportation was 10.7. For basket No.2, the scores were 10.8 and 9.5 after smoking and transportation to the market respectively. Quality and market price as determined by the fish mongers were 200/kg for intact good quality product and 150 00/kg for broken average quality product, after smoking and transportation respectively.

Calculation of total loss as a percentage of maximum potential value.

The financial value of both physical and qualitative losses were calculated and expressed in percentages. In the first basket, 0.68% physical loss was recorded with 18.42% of fish downgraded based on a total load of 20.5 kg. In the second basket, 0.58% physical loss was recorded and 19.47% of product was downgraded, based on a total load of 22.5 kg.

The results of loss assessment of the two baskets containing 300 and 350 pieces of smoked fish after load tracking are presented in Table 4.

Basket No. 1

Table 4. Loss Assessment of two baskets of smoked fish used in the load tracking trial.

Total loss = (Physical loss + Quality loss) maximum potential value = (0.14 kg × 200) + (3.78 × (200 - 150)/4 500 = 4.82%

Basket No. 2

Total loss = (Physical loss + Quality loss)/maximum potential value = (0.13 kg × 200) + (4.38 × (200 - 150)/4 500 = 5.4%

Total loss was 4.8% in Basket 1 (300 pieces) and 5.4% in Basket 2 (350 pieces) respectively.

Note: Physical loss = waste, Economic loss = physical state merit parameters, Good quality fish (N) = 200.00/kg, Average quality fish (N) = 150.00/kg, 1 US $ = 88.00 (December, 1998).

It was found that not much deterioration had occurred in terms of quality. None of the fresh fish purchased for the purpose of this experiment was thrown away due to physical or economic losses. All the fish were smoked and the end product had no sign of poor quality ascribable to the quality level of the starting raw material. This implies that the delay for 4 hours before smoking had little effect on the quality of the end product.

Load tracking- smoked sardinella

The results from load tracking exercise on smoked Sardinella from Magbon-Alade to Oju-Olobun market, a major smoked fish market in Lagos State are presented in Tables 2, 3 and 4. The quality scores for smoked fish in basket No. 1 were 11.6 and 10.7 before and after load tracking, a difference of 0.9. A similar trend was observed for Basket No. 2 with scores of 10.8 and 9.5 after smoking and transportation respectively showing a difference of 1.3. Thus, there was a slightly higher loss in Basket 2 containing 350 pieces of smoked fish compared to Basket 1 with 300 pieces of smoked fish.

When the loss assessment data for the contents of two baskets were expressed in terms of the total number of pieces in each basket a similar trend was observed (Table 4), with Basket No.1 recording a total loss of 4.8% compared to Basket No.2 with a total loss of 5.4%. During loading and transportation to the market, Basket No. 1 was placed on top of Basket No.2. The slightly higher percentage of loss could be due to the fact that the fish in the bottom basket being subjected to a greater pressure than those at the top basket incurred more breakage as a consequence.

The baskets used in this study were the smaller types, which can only contain between 300-350 pieces of smoked fish. However, baskets capable of holding 1 500 - 2 000 pieces are more often used in the packaging and transportation of smoked fish to markets.

4. CONCLUSION

The load tracking method enables one assess the quality of fish objectively and systematically examine all the variables in the distribution chain, which can influence quality. One important components of this methodology is the ability to quickly assess fish quality in the field using sensory evaluation using merit scoring on a simple scale of good quality, average and poor quality products for both fresh and processed fish. Losses were found to be as a result of loading, transportation and unloading.