|Título/s:||Technical note: chemical and sensory assessments in ripened anchovies|
|Autor/es:||Filsinger, Beatriz; Sisti, E.; Bergamaschi, N.J.|
|Institución:||Centro de Investigaciones de Tecnología Pesquera. CITEP. Mar del Plata, AR |
Secretaría de Recursos Marítimos. Mar del Plata, AR
|Palabras clave:||Anchoíta; Pescado salado; Análisis sensorial; Análisis químico; Maduración|
| Ver+/- |
International Journul of Food Sclence und Technology (1987) 22, 73-16
Technical note: Chemical and sensory assessments in
B . F I L S I N G E R * , E . SISTI?. A N D N . J . BERGAMASCHIT
Salting is a traditional process for the preservation of many foods including seafoods.
Anchovics, as preserved, are a heavily salted product made by mixing small, somewhat
oily fish, typically Engraulis species, with salt and allowing the product to mature
over several months (Filsinger et a f . , 1982; Kemp, 1973). The final product has a
characteristic combination of appearance, odour, flavour and texture although the
reactions that produce these characteristic sensory properties are not well known.
Filsinger et al. (1982) have described a scale for the sensory assessment of the
ripening process and related a non-sensory test, the Total Ester Index (TEI), to
ripening time and sensory rating. This paper describes a sensory scale for the cvaluation
of the quality of ripened anchovies and presents data on thc TEI and water activity
of ripened products.
Chemical assessment, fish tcchnology, salted anchovies, sensory quality, water activity.
Materials and methods
Preparation of ripened, salted anchovies
Anchovies (Engraulis anchoita) were caught in the south-eastern Atlantic Ocean
on the Argentinian Platform, approximately 37.4 to 38.8"S, during the Southern hemi-
sphere spring when the fish arrive for spawning. Their weights ranged from 25-33 g/fish.
The salted products were prepared under commercial conditions. Immediately on
receipt at the factory the anchovies were immersed in saturated brine and held in the
brine for 1-2 days before processing. The fish were headed and partially gutted
(nobbed) by hand, washed in brine and then packed in salt in barrels or concrete
vats. A layer of salt was first put in the container then a layer of fish, and so on until
the container was filled with alternate layers of salt and fish finishing with a layer of
salt. A loose-fitting lid was put on top of the mass and weighted with stones or concrete
blocks to compress the solids and expel air. During the ripening process, liquor is
expressed from the fish and covers them. The salted fish were stored for about 9
months at 15~20°C in order to allow the product to ripen. Samples of ripened anchovies
were collected from seventeen factories for analysis.
Authors' addresses: 'Instituto Nacional de Tecnologia Industrial, INTI Centro de Investigaciones de
Tecnologia Pesquera, CITEP, Marcelo T. de Alvear 1168,7600-Mar del Plata and TSecretaria de Recursos
Maritimos, Distrito Mar del Plata, Banquina de Pescadores, Puerto Mar del Plata. Argentina.
74 B. Filsinger, E. Sisti and N . J . Bergamaschi
Anchovies for sensory analysis were washed in water to remove adhering salt,
filleted and examined by four expert assessors. A total of twenty-four fish from each
production batch sampled were presented to the assessors in four batches of six fish
each. The five factors: odour, flavour, colour, consistency and adherence were rated
separately, according to the scale shown in Table 1 , and the sample mean was calculated
from all factors over the four sets.
Table 1. Sensory scoring scheme for ripened anchovies
Factor 100 80 60 40 20
like cured meat
in the whole
I t separates
red or pink in
deep red in the
Dark red, black
red blots andlor
Flesh gets torn in
Fish for chemical analysis were filleted, minced and analysed in duplicate. Total
Ester Index was determined by a modification of the AOAC (1960) procedure
(Filsinger et al., 1982), salt content by the AOAC (1960) procedure and water content
calculated from the loss in weight after drying at 105.+1"C for 24 hr.
Results and discussion
The scoring system described by Filsinger et at. (1982) was designed for evaluating
the progress of ripening of anchovies from the initial stage through to the fully ripened
product. On the basis of experience gained with that scale and following discussions
with anchovy processors, a scale for rating the quality of matured anchovies was
constructed (Table 1). On this scale, running from 0 to 100, the best quality has a
score of 86 or greater, very good quality from 66 to 85, good quality from 46 to 65,
Quality variation in salted ripened anchovies 7.5
regular quality from 26 to 4.5 and anchovies with a score of 25 or less correspond to
spoiled or over-ripe product.
The ratings given to the samples of anchovies are shown in Table 2, along with
salt and water contents as determined by chemical analysis. Most samples fell in the
very good quality grade (scores between 66 and 85) with one graded as best quality
and six graded as good quality.
Table 2. Values of salt and water contents, sensory scores and water activity
for ripened anchovies
Water content Salt content Water activity Sensory
Sample gH20/100gfish gNaClilO0gfish (w,) scores
1 45.66 19.00 0.70 62.2
2 50.05 19.65 0.72 70
3 48.07 17.54 0.74 77.4
4 48.79 19.05 0.72 78
5 50.42 18.11 0.74 70
6 53.21 18.09 0.76 72.5
7 51.42 17.48 0.7s 68
8 51.72 18.59 0.74 75
9 52.6 19.27 0.74 8.5
10 52.14 16.95 0.77 90
11 49.95 18.29 0.74 59.5
12 49.89 18.82 0.73 66.2
13 49.94 21.29 0.69 69.4
14 49.86 20.41 0.71 60.4
1s 53.59 20.25 0.73 58.5
16 48.80 19.53 0.71 69.3
17 49.70 19.42 0.72 80.6
Salt content in the water phase of salted products is important in inhibiting microbial
spoilage while allowing reactions that produce the desired properties to proceed
(Mossell & Ingram, 19.55). A better measure of the ability of salt to preserve foods
is given by the water activity (a,) of the food rather than by the salt content alone.
The a, values of the anchovy samples were calculated from the expression
a, = 1.002-0.042 M,
where M is the molarity of salt calculated in the water phase (Lupin et al., 1981). This
relationship is limited to the range of salt contents up to the point where the water
phase is saturated, approximately 6.0 M, which gives a minimum a, of 0.75.
The water activities calculated from the equation are shown in Table 2 but values
of a, below 0.75 almost certainly mean that undissolved salt was present in the
anchovies as sampled, and do not indicate the true value. Furthermore, Doe et al.
(1982) have shown that the a, of wet salted fish cannot fall below 0.75 unless the
product is dried. There is no obvious association between a, as calculated and sensory
score and, bearing in mind the doubt already expressed that the calculated a, measures
true a, at these salt contents, it must be concluded that a, does not influence quality.
There is no association between TEI and sensory score (Fig. 1). Filsinger et al.
(1982) showed that the index increases during ripening to an asymptote but as samples
reported on here were fully matured it would be expected that the values would be
at the asymptote. The mean value was 10.9 with a standard error of 0.3
76 B. Filsinger, E . Sisti und N . J . Bergamaschi
I I I I I I
50 60 70 80 90
Figure 1. Total Ester Index versus sensory score.
'CDW = Corrected dry weight (Filsinger e ta / . , 1982)
The data presented hcre show that the quality of anchovies varies from batch to
batch but this variation cannot be explained by variations in sa1t:water ratios at the
completion of maturation. The Total Ester Index, although useful for indicating the
progress of ripening, does not predict the quality of the ripened product.
Our grateful thanks are due to Mr Peter F. Howgate of the Torry Research Station,
Aberdccn for assistance in revising the manuscript.
AOAC (1960). Official Methods of'Anulysis. Assori-
ufio?~ of Official Agriculturul Chernisu. 9th ed.
Doe, P.E., Rahila Hashmi, Poulter, R.G. & June
Olley (1982). lsohalic sorption isotherms. I .
Journul or Food Trchndogy, 17, 125-134.
Filsinger, B.. Barassi, C . A . , Lupin, H . M . & Trucco,
R.E. (1982). An objective index for the evaluation
of the ripening of salted anchovy. Journal of Food
Technology, 17, 193-200.
Kemp. M.J. (lO73). The processing of anchovies in
salt and their quality requirements for Spain.
British Sruridard I~i.sti/u~ion, Tec. Rep. T 243, pp.
Lupin, H .M. , Boeri. R.L. & Moschiar, S.M. (19x1).
Water activity and d t content relationship in
moist salted fish products. Jnurriul 01' Food
Technology, 16, 31-38.
Mossel, D.A.A. & Ingrarn, M . (IOSS). The micro-
biology of the microbial spoiIage of foods. lournul
Appl. Bacteriology, 18, 233-268.
(Received 15 February 1985, accepted 16 September 1986)