Introduction to Post Harvest Technology in fish

INTRODUCTION

Post-harvest technology is a multidisciplinary science. It refers to various treatments
and unit operations carried out on harvested crops for the purpose of preservation or
enhancement of quality by eliminating avoidable losses. The important areas of post-harvest technology is the familiarization with major crops, harvesting indices, harvesting technological tools and their maintenance, post-harvest technology-concept and scope, unit operations of crop processing, post-harvest equipments and machinery-operations and maintenance, storage of farm produce and concept of fish-processing centre.

In developing countries, where tropical weather and poorly developed infrastructure contribute to the problem, losses are sometimes staggering proportions. Losses occur in all operations from harvesting through handling, storage, processing and marketing. They are according to the influence of factors such as the perishability of the commodity; ambient temperature and relative humidity which determine the natural courses of decay; fungal and bacterial decay; damage by pests-insects, rodents and birds; the length of time between harvesting and consumption; and practices of post harvest handling, storage and processing.Most often, post harvest losses are symptom rather than the problem. Knowledge of their cause is, therefore, essential deciding measures to prevent them. Such measures may have to be taken by the small farmer, the private trader, a cooperative, the marketing board or other operator, handlers and transporters, wholesale and retail markets, etc.

FISH POST HARVEST TECHNOLOGY

Post Harvest Technology is concerned with although situations where fish is used as a food commodity, from the point of captured to the point of consumption. It embraces handling, transportation, processing and preservation (chilling, freezing, smoking, salting, drying etc.), distribution, marketing product innovation and development, nutritional considerations, standards and specifications, quality control (Collell, 1979)Fish is a rapidly perishable commodity. There it needs to be handled carefully immediately after capture. The technology that is used to keep the quality of the fish after capture is now referred as post harvest technology. It has many branches.

Figure 1: Branches in Post Harvest Technology.

DIFFERENCES BETWEEN FISHERIES TECHNOLOGY AND POST HARVEST FISH TECHNOLOGY

Fisheries Technology	Post Harvest Fisheries Technology
1. Fisheries Technology involves all sciences in Fisheries that are applied in the field e.g. aquaculture technology, feed technology etc.	1. Post Harvest Fisheries Technology is concerned with although situations where fish is used as a food commodity, from the point of captured to the point of consumption.
2. The application of fisheries technology starts from culture and ends to export of the product.	2. Post Harvest Fisheries Technology involves processing, preservation, handling, harvesting, marketing etc.
3. It helps to increase the fisheries production. 4. Post Harvest Fisheries Technology is included by Fisheries Technology.	3. It helps to maintain the quality of fisheries production. 4. It is one kind of Fisheries Technology.
5. Aquaculture technology, feed technology etc.	5. Chilling, freezing, handling, and marketing.

IMPORTANCE OF POST HARVEST FISHERIES

Post harvest fisheries are new hope in our country. Even it is not fully introduced in our country. But this subject is being performed in various areas of our fisheries sector and develops our country in the following ways:

Supply of protein

Fresh and processed fish is important source of protein supply. Application of post harvest technology resist the spoilage of fish muscle. When a fish is in fresh state, it contains a considerable amount of microbes on skin, gill and in intestine. Proper processing with the application of post harvest fisheries technology provides us almost microbes’ free fish. It will maintain the good quality of fish and fisheries products. So, more fish and fisheries products will reach to the consumers which able to meet the protein demand.

Earning foreign exchange

Total fisheries production of Bangladesh is about 15-16 lack ton/year (approx). From this production only 40-50% are exported to foreign countries (recent year) earning 15000 million TK. About 30-40% loss occurs during the post harvest. This loss can be minimized by using the knowledge of post harvest technology. Good quality of fish and fish by-products is ensured by post harvest technology which can be exported and earn a lot of foreign exchange. It is said that Bangladesh earns a lot of foreign exchange by processed fisheries products.

Supply of better quality of fish product

The fisheries resource in Bangladesh is enormous. By applying better technology supply of better quality of fish product will be available to the local and foreign markets. Proper processing and preservation of fish maintains good quality of fish including its protein quality avoids rancidity of lipid or fat and also maintains other nutritional status.

Conversion of fish species into nutritional (biochemical and pharmaceutical) products

Post harvest technology gives us the knowledge of conversion of fish species into products for nutritional and industrial uses. Some biochemical and pharmaceutical products of economical importance from fish and fish wastage is only possible by applying the knowledge of post harvest technology. Protein, vitamins and minerals can be extracted from fishes. For example Cod fish has a wide use in industries which is used to produce cod liver oil. It meets the requirement of vitamin-A.

Production of Ornamental and Perfumed products

Ornamental and perfumed products are prepared from some fish and fisheries products. Without proper processing and preservation it is not possible because it produce bad odor.

Reduction of post harvest losses

Application of post harvest technology helps to reduce the loss of production after harvesting. Fresh and processed fish already are making important contribution to the world’s protein supply. The part of post harvest technology has a great diversity in fisheries sector. By studying on various information about post harvest technology in Bangladesh it is found that there are very few researches on post harvest technology in Bangladesh and the research have done mainly on handling but lack of other side. So, Bangladesh faces enormous losses every year. Many developed countries are varying aggressive in post harvest technology. They have modern technology and equipments. Only introducing the modern technology and equipments in post harvest technology can reduce post harvest losses.

Improve or changes of life style

By helping in additional income post harvest technology can change our common life style. Post harvest technology is also important by the following ways:

- It helps in the production and use of fisheries by product.

- It helps to know about the techniques used for maintaining the quality of fish (processing and preservation)

SCOPE OF POST HARVEST FISHERIES TECHNOLOGY IN BANGLADESH

The scope of the Post Harvest Technology covers all aspects of post harvest research pertaining to fish and fisheries products, from post harvest up to processing. There is considerable room for improvement in the way fish is handled, processed, distributed and marketed for the domestic market. The distribution of benefits may be improved by focusing on traditional producers and processors. Since the scope to expand inshore catches in the long-term is limited, the opportunities that exist for small-scale fisher folk communities in post-harvest value-added production must be tapped. The potential for this in Bangladesh is considerable.

As we know from the definition of post harvest technology, it includes the following areas or scopes that give the special visualization or study to check the qualitative and quantitative losses of fisheries resources.

Fish is one of the most perishable commodities. Considerable wastage occurs after capture. Small-scale fishermen face problems in handling, transporting and marketing fresh fish under difficult conditions and at high ambient temperatures. The absence of adequate facilities both on fishing craft and a shore prevents the distribution of good quality fish. As a result, microbial spoilage and contamination by pathogenic bacteria occurs. This can have important implications for the export trade, especially as more stringent international quality parameters are applied worldwide. Large quantities of fish are also discarded by shrimp vessels because the financial returns do not make it worthwhile to bring the by-catch back to shore. Large quantities of pelagic fish, in particular, are caught at certain times of the year and cannot be processed. Improvements are possible, but technology alone cannot succeed, without a thorough understanding of the social and economic factors and strong support from the Government in tackling the problems of poor infrastructure that affect small-scale fishing communities.

Market trends are now towards convenience foods that can be rapidly prepared. Value addition in fisheries comes through improved handling, processing and storage, and the use of better packaging materials for fish products. The range of convenience fish products includes spreads, dips and salad ingredients as well as main dishes. Preparations involve shrimp and a wide variety of other fish species.

Fishing craft in small-scale fisheries are generally small. They fish the area of the sea close to the shore. The gear they use often determines the fishing methods used. As the craft are small, there is very limited space onboard, which makes proper handling and preservation of the catch difficult. Fishing communities confront severe problems in handling, distributing and marketing fish.

The lack of suitable infrastructure including transport and ice-making plants increases the problems of rapid spoilage. Landing sites are often remote, and it is not economic to provide the infrastructure needed to preserve fresh fish either onboard or immediately on landing. Even when landing sites and road sexist, it is often not economic to transport the catch. Because of these factors, a large part of the catch is processed by traditional methods of salting, sun-drying and smoking.

The best way to preserve fish is by icing it and keeping it cool. However, this is not always technically and economically feasible. The limited use of ice in small-scale fisheries may be due to its high cost or a lack of knowledge about the benefits of using ice. The easiest way is to use a low-cost, sturdy, well-insulated box made of local materials. Boxes should be portable and easy to handle and be designed to meet the rigors of a marine environment and the fishing craft.

Salted, sun-dried and smoked fish are less perishable than wet fish and can keep for several weeks. However, unless the processing is done very carefully, physical losses can occur which reduce quality and quantity and lower value to the fish processor.

Women play a vital role in post harvest activities, particularly in the small-scale sector where they work in shore-based activities such as handling, processing and marketing of catch. Women have traditionally been involved in fresh and dried fish marketing, which can be seen as an extension of the production process, and provide a crucial link between the supplier and the customer in the rural areas. However, they often face difficulties in procuring, distributing and marketing wet fish and fish products. Any initiatives in the small-scale post harvest sector must take into account the role played by these women.

Job opportunity

Many people can be employed in the fish processing industries and fish collector agencies. Thus post harvest technology provides job opportunity. If new industry is established the opportunity will be greater. So, it can be said that application of fish post harvest technology in our country plays an important role in solving the unemployment problem in Bangladesh. Job opportunities may be of two types:

Wage Employment
Self Employment

Table: Job opportunities in Post Harvest Technology

Job opportunity

A)Wage Employment

Seed Processing Plant Operator
Crop Processing Technician
Field Supervisor/Agricultural Consultant
Mini Oil/Dal Mill Operator

B) Self Employment

Proprietor of fish-Processing Centre
Primary Processor
Farm Advisor/Fish-processing Consultant

Quality aspects

The quality aspects include quality components, standards and assessment, properties of commodities and tests for maturity determination.

Economics and marketing

It includes economics and costs of post harvest activities, marketing systems for specific commodities, imports and exports and food policy and supply.

Handling, packaging and transport

Including handling and packaging techniques, handling machinery, packaging materials, transport, impact damage assessment, washing and cooling.

Engineering and electronics in post harvest technology

Including impact of engineering and electronics in post harvest technology, the increased automation of processes and development of techniques and processes.

Storage

Including aspects of storage systems, environments and treatments, controlled atmosphere storage, modified atmosphere packaging (MAP), effects of pre-harvest factors on storage quality, storage characteristics, breeding for improved storage quality, moisture absorption in storage, physiology and biochemistry of storage, storage disorders, storage aeration and design and properties of storage facilities.

Ripening and senescence

Including the physiology, biochemistry and genetics of ripening and senescence, respiration of harvested produce, and senescence.

Spoilage, deterioration and losses

Including incidence, biology, prevention and control, biological control, post harvest decay, resistance to storage decay, breeding for resistance and assessment of post harvest losses.

Drying

Including grain drying, alternative drying methods, drying of fish & fisheries products and dryer design.

Minimal processing such as washing and cutting may be included where it is of relevance to the processes being reviewed.

OBJECTIVES OF POST HARVEST TECHNOLOGY

To reduce post-harvest losses of fish and fisheries products.
To improve the quality of fishes and seafood products.
To introduce new flexible pouch packing technology.
To implement substantially delayed after approval.
To reduce the cost of food packaging, processing and preservation.
To have a good concept on areas like fish handling, preservation and processing, with focus also on safety problems that are specific of seafood.
To develop skilled personnel for undertaking/organizing/supervising/assisting
in post-harvest technology activities.
To acquaint the students with gainfully remunerative occupations in the field of
post-harvest technology.
To develop proficiency in the efficient use of post-harvest technology for the
benefit of producers.
To train manpower to meet the needs of producers, suppliers and consumers
of post-harvest equipments.
To train young entrepreneurs for self employment by way of developing
processing Centers at village levels.
To impart knowledge on the safe and judicious use of post-harvest equipments
with the aim of processing of farm produce at producer’s level.
To provide fish-processing consultancy services.

STRATEGY FOR THE DEVELOPMENT OF FISH POST HARVEST FISHERIES IN BANGLADESH

For substantial exploitation of the fisheries resources to meet our present demand for food and other by-products and to generate export, we must decide a definite research strategy. To achieve this strategy the following broad points should be taken into consideration to formulate national action program:

First and foremost there should be well defined national policy relating to utilization of fishery resources.
Fish post harvest technological research centre at important location should be established.
A viable action-program to stream line and coordinate research organizations in the light of national need should be taken up.
A direct communication between research organizations and the private industries should be established for development of quality products.
Private entrepreneurs should be encouraged to finance research projects.
International cooperation among the scientists should be encouraging through exchange program.
Fisheries graduate should be engaged in different fish processing and fish by-product processing industries to ensure quality products.
Apply modern technology
Establish training centre
Developed processing centre
Strictly apply the rules and regulation relating to post harvest fisheries.

RELEVANT RESEARCH IN POST HARVEST FISHERIES

Find out the composition of fish and self life of different fish species.
Processing technique of crab, mollusk and other economical important fisheries item.
Marine fisheries drying technique.
Development of harvesting technique.
Development of marketing technique.
Extension of HACCP system.
Utilization of by-products.
Improvement of salting, drying technique.
Development of traditional method of small scale production of dry fish.
Development of chemical and organoleptic test.
Selection of packaging materials to extend their shelf life.
Unwanted contaminants (antibiotics) in frozen product.

CONCLUSION

In a word, Fish Post Harvest Technology is parts and parcel in modern fisheries production. So, to develop culture system or to increase production, Post Harvest Technology must be ensured at first.