164
aids reduced opening time. The shucking aids at 60 °C increased the incidence of
opening to 100% in 2–3 min (Ekanem and Achinewhu 2000).
3.1.2.3 Clam Processing and Preservation
Chilling/Refrigerating of Clams
Chilling by ice and mechanical refrigeration are the most common means of retarding microbial and biochemical spoilage. Temperature control is the most critical
factor for providing a good product. When clams are harvested during the warm
summer months, on-deck temperatures can exceed 30 °C. For optimum quality and
shelf life, bivalves should be cooled and stored at temperatures less than
10 °C. Processing shellfish for the live market is usually limited to washing, sorting,
and packing. Hard clams (Mercenaria mercenaria) often are sold in the shell by
size, with smaller clams being higher priced. The clams are sorted either manually
or mechanically, and then washed and boxed for shipment. The Manila clam (Tapes
philippinarium) is handled in a manner similar to the Mercenaria clam. The softshell clam (Mya arenaria) also is washed and boxed before sale. The clams are
often placed in clean water for a short time to remove grit and sand from the intestinal area (Hackney 1990). Live clams are generally displayed on the ice which
keeps them cold and extends their longevity. It should be noted that these products
cannot be overwrapped, or they will suffocate (Haby and Coale Jr 1990).
The shelf life of refrigerated clam is relatively short. It is susceptible to microbiological and chemical deterioration and hence, the consumption of this product is
expected to be shortly after purchase. The extension of product shelf life is very
important to increase the market and satisfy consumer demands (Vongsawasdi
et al. 2011).
Clams stored in direct contact with ice and non-contacted in packaged form were
found to remain in good condition for 2 and 4 days, respectively (Basu and
Gupta 1984).
The temperatures of the harvested clams should be kept under control within
20 h after harvest in summer. The product should be kept at a temperature of 7.2 °C
or less and should not be out of temperature control for more than 2 h. The Food and
Drug Administration (FDA) states that in accordance with the interstate transport
regulations, it is necessary to allow shippers to cool their products to a temperature
of 10 °C or less. Clam transporters prefer to transport the product quickly, usually
within 2 h of receipt, until the product has cooled sufficiently (Brenton et al. 2001).
In a study, the live clams were transferred to the laboratory. After washing, they
were depurated. The clams were steam shucked at 110 °C for 10 min in a retort. The
shells were opened, and the shucked meat was collected manually, packed in two
different material polyester polyethylene laminate (PEST-PE) and low-density
polyethylene (LDPE) and stored in a box with flake ice at 2 °C. At the end of study,
it was found that the shelf life of black clam was 22 days in PEST-PE and 16 days
in LDPE (Sreedevi et al. 2018).
3 Molluscan Shellfish
aids reduced opening time. The shucking aids at 60 °C increased the incidence of
opening to 100% in 2–3 min (Ekanem and Achinewhu 2000).
3.1.2.3 Clam Processing and Preservation
Chilling/Refrigerating of Clams
Chilling by ice and mechanical refrigeration are the most common means of retarding microbial and biochemical spoilage. Temperature control is the most critical
factor for providing a good product. When clams are harvested during the warm
summer months, on-deck temperatures can exceed 30 °C. For optimum quality and
shelf life, bivalves should be cooled and stored at temperatures less than
10 °C. Processing shellfish for the live market is usually limited to washing, sorting,
and packing. Hard clams (Mercenaria mercenaria) often are sold in the shell by
size, with smaller clams being higher priced. The clams are sorted either manually
or mechanically, and then washed and boxed for shipment. The Manila clam (Tapes
philippinarium) is handled in a manner similar to the Mercenaria clam. The softshell clam (Mya arenaria) also is washed and boxed before sale. The clams are
often placed in clean water for a short time to remove grit and sand from the intestinal area (Hackney 1990). Live clams are generally displayed on the ice which
keeps them cold and extends their longevity. It should be noted that these products
cannot be overwrapped, or they will suffocate (Haby and Coale Jr 1990).
The shelf life of refrigerated clam is relatively short. It is susceptible to microbiological and chemical deterioration and hence, the consumption of this product is
expected to be shortly after purchase. The extension of product shelf life is very
important to increase the market and satisfy consumer demands (Vongsawasdi
et al. 2011).
Clams stored in direct contact with ice and non-contacted in packaged form were
found to remain in good condition for 2 and 4 days, respectively (Basu and
Gupta 1984).
The temperatures of the harvested clams should be kept under control within
20 h after harvest in summer. The product should be kept at a temperature of 7.2 °C
or less and should not be out of temperature control for more than 2 h. The Food and
Drug Administration (FDA) states that in accordance with the interstate transport
regulations, it is necessary to allow shippers to cool their products to a temperature
of 10 °C or less. Clam transporters prefer to transport the product quickly, usually
within 2 h of receipt, until the product has cooled sufficiently (Brenton et al. 2001).
In a study, the live clams were transferred to the laboratory. After washing, they
were depurated. The clams were steam shucked at 110 °C for 10 min in a retort. The
shells were opened, and the shucked meat was collected manually, packed in two
different material polyester polyethylene laminate (PEST-PE) and low-density
polyethylene (LDPE) and stored in a box with flake ice at 2 °C. At the end of study,
it was found that the shelf life of black clam was 22 days in PEST-PE and 16 days
in LDPE (Sreedevi et al. 2018).
3 Molluscan Shellfish