Freezing and refrigerated storage in fisheries


 

 

 

 

 

Table of Contents


FAO FISHERIES TECHNICAL PAPER - 340
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

W.A. Johnston, F.J. Nicholson, A. Roger and G.D. Stroud
CSL Food Science Laboratory
Torry, Aberdeen, Scotland, UK

FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome, 1994

The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country territory city or area or of its authorities or concerning the delimitation of its frontiers or boundaries.

M-47
ISBN 92-5-103579-2

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying or otherwise, without the prior permission of the copyright owner. Applications for such permission with a statement of the purpose and extent of the reproduction, should be addressed to the Director, Publications Division. Food and Agriculture Organization of the United Nations. Via delle Terme di Caracalla, 00100 Rome, Italy.

FAO 1994

This electronic document has been scanned using optical character recognition (OCR) software and careful manual recorrection. Even if the quality of digitalisation is high, the FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.


TABLE OF CONTENTS


Preparation

1. BIOLOGICAL ASPECTS

1.1 Composition of Fish
1.2 Spoilage of Fish

2. INFLUENCE OF TEMPERATURE

2.1 What happens during freezing
2.2 What is quick freezing
2.3 Double Freezing
2.4 Handling of fish before freezing
2.5 Frozen fish
2.6 Frozen fish products
2.7 Time-temperature tolerance
2.8 Codes of practice

3. QUALITY ASSESSMENT

4. FREEZERS

4.1 Types of freezer
4.2 Freezer operating temperatures
4.3 Space requirements for freezing
4.4 Labour requirement for freezing
4.5 Calculation of freezer refrigeration load
4.6 Ordering freezers

5. FREEZING TIME

5.1 Variables which affect freezing times
5.2 Calculation of freezing time
5.3 Sample freezing times

6. TREATMENT OF FISH AFTER FREEZING

6.1 Glazing
6.2 Packaging of frozen fish

7. COLD STORES

7.1 Recommended storage temperature
7.2 Factors limiting storage life
7.3 Choice of Planners and Designers
7.4 Shape and Size
7.5 General Layout
7.6 Construction Methods
7.7 Insulation
7.8 Vapour Barriers
7.9 Floors
7.10 Types of cold store
7.11 Cold air distribution
7.12 Defrosting
7.13 Factors affecting storage conditions
7.14 Product handling and storage
7.15 Refrigeration

8. CALCULATION OF COLD STORE REFRIGERATION LOAD

8.1 Cold store capacity

9. WEIGHT LOSS FROM FISH DURING FREEZING AND COLDSTORAGE

9.1 Freezer weight loss
9.2 Cold store weight loss

10. FINANCE OF FREEZING AND COLD STORAGE

10.1 Cost of freezing
10.2 Costing of freezing
10.3 Cold store costs
10.4 Costing of cold storage

11. SPECIAL OPERATION CONSIDERATIONS

11.1 Care and cleanliness
11.2 Personnel working in cold stores
11.3 Safety
11.4 Security
11.5 Instruments
11.6 Energy management and conservation

12. PLANNING A COLD STORE

13. FREEZING AT SEA

13.1 Why freeze at sea?
13.2 Type of freezer vessel
13.3 How good are sea-frozen fish?
13.4 Freezers for use at sea
13.5 Handling fish before freezing
13.6 Handling frozen fish
13.7 Cold stores on freezer vessels
13.8 Unloading freezer vessels

14. TRANSPORT OF FROZEN FISH

15. REFRIGERATION PLANT REQUIREMENTS

15.1 Compressors
15.2 Condensers
15.3 General notes on refrigeration plant
15.4 Power requirements

16. REFRIGERATION PLANT OPERATORS

17. TEMPERATURE MEASUREMENTS OF FISH

17.1 Temperature measurement of wet fish
17.2 Temperature measurement of fish during freezing
17.3 Temperature measurement of frozen fish
17.4 Summary of rules for measuring fish temperature

18. C F Cs

18.1 History
18.2 Phase-Out
18.3 Alternatives
18.4 Advice
18.5 Future

19. SOME RELATED FACTS AND FIGURES

20. CONVERSION FACTORS

Metric and British Units
Metric, British and SI Units

APPENDICES

APPENDIX 1 Selected Reading
APPENDIX 2 Specification for sensory evaluation of raw cod
APPENDIX 3 Cold store quality assurance audit - sanitation and housekeeping
APPENDIX 4 Safety instructions for cold store
APPENDIX 5 Basic check list for planning cold stores