|Small-Scale Processing of Fish (ILO - WEP, 1982, 140 p.)|
|CHAPTER II. SALTING - DRYING - FERMENTING|
A general plan for a fish curing yard is given in Fig.II.7 and an indication of the yields obtained during the preparation of salted dried mackerel is given in Fig.II.8. This plan applies mostly to the production of salt/dried fish.
The scale of the various parts of the curing yard will depend on the amount of fish to be processed and the length of the processing period. These will in turn depend on the nature of the raw material and its supply as well as the process involved. Field evaluation of these factors must take place so that the correct scale of facilities are provided.
Some relevant factors are indicated below for the production of salted dried fish, but similar considerations also apply to other cured products:
- Is the fish supply seasonal or continuous throughout the year and, hence, what quantities of fish will the curing yard be required to process?
- What salting technique will be used, how long does it take and, hence, what scale of salting facilities are required? As a rough guide, 1 tonne of fish will require up to 2 cubic meter vat for the duration of a pickle curing process.
- How long does it take the fish to dry to the required moisture content under the prevailing climatic conditions and, hence, what area should the drying yard cover. As a rough guide, it takes up to 100 m2 of drying area to spread a tonne of fish (wet weight). This figure will vary depending on the shape and size of fish being processed. 6-8 kg fish/m2 of rack should be needed for artificial drying and smoking operations.
It must be noted that there will be fluctuations in the supply of fish on a day to day basis. Adverse drying conditions will also increase the time required for drying, and thus an increased drying area will be necessary. Initially, it would be advisable to allow-2-3 times the estimated minimum scale of facilities required to cope with an average amount of fish and to select a site where further expansion can easily be achieved. These generalisations should not be used as a substitute for an investigation of the actual requirements at a particular location.
Figure II.7. A model lay-out for the preparation of salted sun-dried fish
Figure II.8. Material balance data in the preparation of sun-dried salted mackerel