Small-Scale Processing of Fish (ILO - WEP, 1982, 140 p.): CHAPTER I. INTRODUCTION: II. PROCESSING METHODS

Small-Scale Processing of Fish (ILO - WEP, 1982, 140 p.)

(introduction...)

Acknowledgements

Preface

CHAPTER I. INTRODUCTION

(introduction...)

I. FISH SPECIES

II. PROCESSING METHODS

III. PREVENTION OF LOSSES AND SPOILAGE OF FISH

(introduction...)

III.1. Prevention of spoilage of fish before processing

III.2. Prevention of spoilage of fish during processing

III.3. Prevention of spoilage of fish after processing

CHAPTER II. SALTING - DRYING - FERMENTING

(introduction...)

I. FISH PREPARATION

(introduction...)

I.1. Equipment for fish preparation

I.2. Gutting and splitting methods

II. SALTING

(introduction...)

II.1. Kench salting

II.2. Pickle curing

II.3. Brine salting

II.4. Salt quality

III. DRYING

III.1. Basic principles

III.2. Natural drying

III.3. Artificial drying

III.4. Solar drying

IV. PACKAGING AND STORAGE

V. METHODS OF PREPARATION

(introduction...)

V.1. Dried/salted fish

V.2. Dried-unsalted fish

V.3. Dried/salted shark

VI. GENERAL PLAN FOR A FISH CURING YARD

VII. FERMENTED FISH PRODUCTS

(introduction...)

VII.1. Products which retain substantially the original form of the fish

VII.2. Fish paste products

VII.3. Liquid fish products

VII.4. Packaging

CHAPTER III. FISH SMOKING AND BOILING

(introduction...)

I. SMOKING

(introduction...)

I.1. Fish preparation prior to smoking

I.2. Cold smoking

I.3. Hot smoking

I.4. Fuel

I.5. Smoking kilns

I.6. Preparation of some smoked fish products

I.7. Packaging and storage of smoked fish

II. BOILED FISH PRODUCTS

(introduction...)

II.1. Traditional processing methods

II.2. Quality of boiled fish products

CHAPTER IV. THERMAL PROCESSING

(introduction...)

I. RAW MATERIALS

II. ENERGY AND MANPOWER REQUIREMENTS

III. PROCESSING OPERATIONS

III.1. Filling and sealing

III.2. Sterilisation

III.3. Cooling

IV. QUALITY CONTROL

V. POSSIBLE ALTERNATIVES TO THE USE OF METAL CANS

(introduction...)

V.1. Reusable container

V.2. New developments in aseptic (retortable) pouches

CHAPTER V. ALTERNATIVE TECHNOLOGIES: EVALUATION, EMPLOYMENT GENERATION AND MANPOWER TRAINING

(introduction...)

I. ASSESSMENT OF COSTS

II. SALTING AND DRYING

III. SMOKING

IV. THERMAL PROCESSING

V. EMPLOYMENT IMPACT OF ALTERNATIVE FISH PROCESSING TECHNOLOGIES

VI. ASSISTANCE TO THE SMALL-SCALE FISHERIES SECTOR: MANPOWER TRAINING AND SUPPORTING SERVICES

(introduction...)

VI.1. The socio-economic framework

VI.2. Infrastructural requirements

VI.3. Organisation of production and marketing of fresh and cured fish

VI.4. Extension services and training

CHAPTER VI. IMPACT OF SMALL SCALE FISH PROCESSING OPERATIONS ON THE ENVIRONMENT

(introduction...)

I. FISH RESOURCES

II. WASTE DISPOSAL

III. AIR POLLUTION

IV. CONCLUDING REMARKS ON ENVIRONMENTAL IMPACT

APPENDICES

APPENDIX I. Codex Codes and Standards issued by the Secretariat of the Joint FAO/WHO Food Standards Programme, FAO, Rome.

APPENDIX II. Bibliographical references

QUESTIONNAIRE

OTHER ILO PUBLICATIONS

BACK COVER

II. PROCESSING METHODS

This section briefly reviews processing methods which will be described in greater detail in subsequent chapters. These methods do not include technologies which are more appropriate for capital-intensive medium and large-scale processing plants.

II.1. Salting

During slating, the flesh of the fish looses some of its water and is impregnated with salt. Rapid penetration of salt into the flesh is desirable for good protection of the product during the curing process. Salting can be done by a number of methods. The obtained results are influenced by such factors as climate, salt quality, type and quality of the fish used, the type of product desired by consumers and cost. Fish may be slated by rubbing dry salt into the flesh or by immersing the fish in a brine (a solution of salt in water). The juices extracted from the fish during dry salting can be allowed to drain away (Kench curing) or they can be contained in order to keep the fish covered by a salty liquid or “pickle” (pickle curing).

II.2. Drying

Simple drying in the sun is one of the commonest methods of curing used in tropical countries. Natural drying using the action of sun and wind constitutes one of the least expensive drying methods. Furthermore, the type of packaging used for dried fish is also fairly inexpensive. Altogether, dried fish is particularly suited for low-income groups which cannot afford expensive fish products. Simple improvements, such as the use of drying racks raised above ground level can increase drying rates and reduce contamination, thus helping to make products of good quality.

Mechanical dryers are relatively expensive to buy and operate. Although the output may be of better quality than that produced by natural drying, artificially dried fish will, most probably, be too expensive for the majority of low-income consumers.

II.3. Smoking

During smoking, the heat from the fire dries the fish while chemicals from the smoke impregnate the flesh. The obtained flavours depend both on the raw materials used and the length of time the fish are smoked.

There are many traditional smoking methods: these range from simple open fires or smoke pits to smokehouses covering a considerable area. Structures used in traditional smoking methods can be built with local materials and labour. They have however a major disadvantage: most of these structures are wasteful of fuel, usually firewood, which has become both scarce and expensive in some countries. A number of modified and improved designs have been produced in order to partially overcome the above disadvantage. The modified structures are easier to use than the traditional pits, and produce smoked fish of a more even quality, using less fuel.

Smoking is one of the most common curing process wherever salt is in short supply, most notably in the inland fisheries of Africa.

II.4. Other curing methods

Brine preserved, pickled and fermented fish products such as fish pastes and sauces are widely made in South-East Asia but not elsewhere in the tropics. Spoilage is prevented in these cures by the addition of large quantities of salt. A fish paste is obtained whenever a moderate amount of breakdown of protein occurs. If the breakdown is permitted to continue further, a liquid sauce is obtained. All these products contain large quantities of salt, and can there fore be eaten only in small quantities at one meal.

Boiled fish products are also of considerable importance in South-East Asia. Some products are simply boiled; they can then be kept for only a few days at tropical temperatures. Sometimes, the boiled fish is dried and the products can then be kept for many months. A few products are made by boiling and salting in sealed containers, yielding cured fish with a relatively long storage life.