dc.description.abstract |
Present study implies different techniques of smoke-drying to preserve three
freshwater small indigenous species (SIS) of fishes of Bangladesh viz .,
chapila (Gudusia chapra), kaika (Xenentodon cancila) and baim
(Mastacembe/us panca/us) using smoke curing method . Smoke curing of
chapila , kaika and baim fish was conducted in an improved type of traditional
smoking kiln by using tamarind wood chips and rice husks as smoke Source .
The experimental chapila, kaika and baim fish samples were treated with four
different treatments namely, Unsalted (US), Salted (S), Salt+ Turmeric (S+ T)
and Salt+Garlic (S+G) . Performance, quality assessment and shelf life study
of the smoke-dried chapila, kaika and baim fish products were done . This
study assessed the comparative changes in sensory characteristics,
microbiological quality , water reconstitution time and biochemical aspects of
fresh and smoke-dried freshwater SIS fish, chapila, kaika and baim during
storage at room (26-31 dc) and refrigeration (4
D
C) temperature using standard
methods of analyses . In fresh process condition water reconstitution rate was
faster in salt treated (S) smoke-dried chapila , kaika and baim fish products but
slower in Unsalted products . Remarkably kaika fish exhibited an enormOUSly
rapid initial rate of reconstitution . Important mineral composition e.g. Ca , Mg ,
Fe, Zn , Cu and Mn were also determined in fresh fish and fresh smoked fish
products and found that smoke-dried fishes is a good source of minerals .
Results of the freshly collected chapila , kaika and baim fish had been found to
contain moisture, protein, fat , ash, TVB-N and TVC 76.41±0.02%,
10.53±0.03%, 11.62±O.03%, 1.50±O.03% , 2.40±O.03 mgN/100g and 3.1x105
cfu/g ; 77 .67±0.03% , 14.27±O.03%, 4.66±O.01% , 2.94±O.04% , 4.92±0.04
mgN/100g and 4.1x105 cfu/g and 77.21±O.08%, 15.17±0.03% ,
6.13±0.03%,1.72±O.03% , 3.16±0.02 mgN/100g, and 5.8x104 cfu/g
respectively.
After smoke-drying moisture (%) and TVC (cfu/g) decreased whereas protein
(%), fat (%), ash (%) and TVB-N value (mgN/100gm) increased in the smoke
dried fish samples when compared to fresh fish samples . Salt (NaCI) content
in the freshly prepared smoked products ranged between 2.87 and 3.75 %.
During storage at room and refrigeration temperature the percentage of
moisture, TVB-N value (mgN/100g) and TVC (cfu/g) was increased whereas
protein, fat ash and salt content were found to be decreased . Direct relation
was observed between moisture and TVB-N and moisture and TVC whereas
inverse relation was revealed between sensory score and TVB-N value.
However, there was also a general decline in sensory characteristics and
scores on color, odor, texture , general appearance and mean of general
acceptability score of all the smoke-dried fish products as storage duration
XIX
increased and the acceptability score <3.5 was considered as rejected or
spoiled for all the smoke-dried fish samples . On the other hand mineral
elements were detected in the decreasing order of Ca followed by Mg , Fe , Zn ,
Cu and Mn in fresh fishes.
The shelf life of US , S, S+ T and S+G treated smoke-dried chapila, kaika and
baim fish products varied considerably during storage at room and
refrigeration temperature. From the overall performance , smoke-dried baim
fish showed better shelf-life than smoke-dried chapila and kaika fish .
However, all the smoke-dried fish products stored at refrigeration temperature
(4°C) showed a longer shelf life (except S+ T treated Kaika) than room
temperature (26-31
o
C) . The highest shelf life was found to be 27 months in
case of ' S+ l' treated smoke dried baim fish with all its sensory qualities as
good conditions during storage at refrigeration temperature . On the contrary
the lowest shelf life was observed in 'US ' smoke dried chapila, kaika and baim
fish products. Among the three fish species , 'US ' smoke dried chapila and
kaika fish were found lowest shelf life and the duration was 4 months during
storage at room temperature .
The information obtained in this study of smoke curing demonstrated a better
efficient method of fish processing in terms of the retention of protein value
having good sensory scores and reduction in the moisture content which
could be useful to fish consumers, processors and nutritionists in the efficient
management of fish resources by increasing its shelf life for a significant
period of time. |
en_US |