VII.2. Fish paste products
In this processing method, the fish or shrimp are pounded with
salt so that a paste results. The paste is then subject to periods of sun drying
prior to packing in sealed containers for maturation. Moisture contents range
from 35 to 50% so that almost half the water is lost during processing. Fish
pastes represent a considerable portion of the protein intake of many people in
South-East Asia (FAO, 1971), especially by the poorest sections of the
population. In many fish pastes, carbohydrate-rich materials, such as fermented
flour, bran or rice are added.
VII.2.1. Ngapi (Burma)
The raw material used in this product is small anchovy
(Anchoviella comersonii) or shrimp (preferably the small planktonic types
which give a better natural pink colour to the product). There are a number of
methods for making ngapi, depending on the type of product required. In
one process, which uses one part of salt to three parts of partially dried fish,
the fish or shrimps are first washed in sea water and then dried for two days in
the sun. About half of the required salt is then added to the fish and mixed in
a bamboo basket. This mixture is pounded for several hours until a paste is
formed. The paste is then packed into wooden tubs or boxes, care being taken
that all air bubbles are removed. Fermentation takes place over 7 days and the
paste is then removed, further pounded for three hours during which time the
remaining salt is mixed in. The mixture is then spread out to dry in the sun for
3-5 hours. The product is repacked into tubs and the fermentation continues for
about a month. After a third pounding, it can be packed for sale in cellophane
or brown paper. Artificial dyes are often added to improve the colour. However,
their use is not recommended as some may be toxic. When stored anaerobically in
the tubs or earthenware pots, the product is said to keep for about 2 years. The
average composition of a shrimp or fish ngapi is 43% moisture, 20%
protein, 1% ammonia, 2% fat and 22% salt.
VII.2.2. Bagoong (Philippines)
Bagoong is one of the major preserved fish products of
the Philippines where, in many communities, it constitutes a staple food. The
product is also exported as far as the USA to the large ethnic Filipino
community. A by-product of bagoong is patis, which is the exuded
liquor from the fermentation process and is similar to the Vietnamese
nuoc-mam.
Bagoong has a pasty consistency, and is reddish in colour
with a slightly fishy cheese-like odour. It can be prepared from fish of the
genera Stolephorus, Sardinella and Decapterus, and small
shrimp. In the process described by Subba Rao (1961), the fish are washed in
clean water, placed in a concrete or wooden vat and mixed thoroughly with salt.
The ratio of salt to fish is about one third. The mixture of fish and salt is
then transferred to earthenware jars, oil drums or cement tanks and either
sealed immediately or, preferably, covered with cheese cloth for five days and
then sealed. The sealed containers are held in the sun for one week and the
product is then transferred to five gallon cans. These cans are, in turn, sealed
by soldering of the lids, and the product is allowed to ferment further for
between three months and one year.
The storage life of the product is many years, and the typical
composition is not less than 40% total solids, 12.5% protein and 20-25% sodium
chloride.