{"id":458,"date":"2026-10-01T07:05:31","date_gmt":"2026-09-30T22:05:31","guid":{"rendered":"https:\/\/magazine.samsammulsan.com\/how-does-the-oyster-processing-flow-differ-by-product-a-guide-to-shucking-boiling-and-freezing-branches\/"},"modified":"2026-10-02T11:03:53","modified_gmt":"2026-10-02T02:03:53","slug":"how-does-the-oyster-processing-flow-differ-by-product-a-guide-to-shucking-boiling-and-freezing-branches","status":"publish","type":"post","link":"https:\/\/magazine.samsammulsan.com\/en\/how-does-the-oyster-processing-flow-differ-by-product-a-guide-to-shucking-boiling-and-freezing-branches\/","title":{"rendered":"How Does the Oyster Processing Flow Differ by Product? A Guide to Shucking, Boiling, and Freezing Branches"},"content":{"rendered":"

The oyster processing flow varies depending on the product form and the heating\/storage methods. The preparation process differs between oysters distributed in the shell and products using only the oyster meat, and heating or freezing stages are added depending on whether they are boiled or frozen. In this article, we look at what is done at each stage\u2014from raw material receipt to washing, shucking, boiling, freezing, and packaging\u2014and which items are managed for each product.<\/p>\n

\"Indoor<\/p>\n

Photo of oyster production facilities provided by Samsam Mulsan.
Photo credit: Samsam Mulsan<\/p>\n

Required processes vary depending on the product form and intended use.<\/strong><\/h2>\n

Shell type, shucking status, raw vs. boiled status, refrigerated vs. frozen status, and final use are distinct classifications. Shucked oyster meat can be raw-refrigerated, raw-frozen, or boiled-frozen, and IQF refers to a method of individual quick freezing rather than heat treatment.<\/p>\n

\n\n\n\n\n\n\n\n\n
\n

Product Branch<\/p>\n<\/td>\n

\n

Core Processes Required<\/p>\n<\/td>\n

\n

Optional Processes<\/p>\n<\/td>\n

\n

Primary Verification Data<\/p>\n<\/td>\n<\/tr>\n

\n

Live Shell-on Oysters<\/p>\n<\/td>\n

\n

Raw material verification, external washing, sorting, distribution maintaining live state<\/p>\n<\/td>\n

\n

Shucking, meat washing, boiling, freezing<\/p>\n<\/td>\n

\n

Harvest\/shipment info, survival\/damage, time\/temperature<\/p>\n<\/td>\n<\/tr>\n

\n

Raw Half-shell<\/p>\n<\/td>\n

\n

External washing, opening, shell sorting, cooling\/packaging<\/p>\n<\/td>\n

\n

Complete shucking, boiling<\/p>\n<\/td>\n

\n

Raw material lot, operational hygiene, shell foreign matter records<\/p>\n<\/td>\n<\/tr>\n

\n

Raw Refrigerated Shucked Oysters<\/p>\n<\/td>\n

\n

Shucking, meat washing\/sorting, draining, refrigerated packaging<\/p>\n<\/td>\n

\n

Boiling, freezing<\/p>\n<\/td>\n

\n

Process water, drainage\/net weight, time\/temperature<\/p>\n<\/td>\n<\/tr>\n

\n

Raw Frozen Shucked Oysters<\/p>\n<\/td>\n

\n

Shucking, washing\/sorting, freezing, frozen packaging<\/p>\n<\/td>\n

\n

Boiling<\/p>\n<\/td>\n

\n

IQF\/Block specifications, freezing\/glaze records<\/p>\n<\/td>\n<\/tr>\n

\n

Boiled Shucked Oysters<\/p>\n<\/td>\n

\n

Heating, cooling, sorting, freezing\/packaging if necessary<\/p>\n<\/td>\n

\n

Maintaining raw state<\/p>\n<\/td>\n

\n

Heating validation, cooling, post-heating handling records<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

‘Gak-gul’ refers to oysters with the shell attached. Storage methods and items to check upon receipt vary depending on whether they are live, refrigerated, or frozen shell-on oysters. Therefore, when choosing oysters, you must consider not only the shell form but also whether they are raw or boiled, refrigerated or frozen, and the freezing method such as IQF or block freezing<\/a>.<\/p>\n

Origin and product condition are verified during raw material receipt.<\/strong><\/h2>\n

When raw materials are received, the origin and product condition are checked first. For live bivalve mollusks, harvest area and shipment information<\/a> are examined, along with relocation or purification conditions carried out under official control if necessary. For live oysters, survival and shell condition are checked, and for shucked raw materials, container condition and cooling history are verified. Supplier, sea area\/origin, harvest\/shipment info, lot, and time and temperature of receipt are also recorded.<\/p>\n

Raw material information verified at receipt must be linked to processing and shipment records to identify which raw materials were used in which products. Since it is difficult to verify raw material history with finished product test reports alone, raw material receipt records of the same production lot, applied processes, and finished product\/shipment records are viewed together. It is also verified whether the receipt, cooling, shucking, washing, and packaging stages<\/a> indicated on the process flow chart match the actual records.<\/p>\n

Distinguishing between shellfish depuration, process seawater treatment, and oyster meat washing<\/strong><\/h2>\n

The term ‘seawater purification’ should be read by distinguishing between the process of depurating shellfish and the process of treating water used in the production line. The task of washing shucked oyster meat is also a different process.<\/p>\n

\n\n\n\n\n\n\n
\n

Classification<\/p>\n<\/td>\n

\n

Target of Treatment<\/p>\n<\/td>\n

\n

Purpose<\/p>\n<\/td>\n

\n

Limitations of This Process Alone<\/p>\n<\/td>\n<\/tr>\n

\n

Shellfish Depuration<\/p>\n<\/td>\n

\n

Live shellfish<\/p>\n<\/td>\n

\n

Reduction of some microbial contamination using filtration and discharge activities<\/p>\n<\/td>\n

\n

Universal removal of viruses, Vibrio, toxins, and heavy metals<\/p>\n<\/td>\n<\/tr>\n

\n

Process Seawater Treatment<\/p>\n<\/td>\n

\n

Water used in processing<\/p>\n<\/td>\n

\n

Management of process water suitability through filtration, UV, ozone, etc.<\/p>\n<\/td>\n

\n

Depuration of the oyster itself<\/p>\n<\/td>\n<\/tr>\n

\n

Shucked Oyster Meat Washing<\/p>\n<\/td>\n

\n

Shucked oyster meat<\/p>\n<\/td>\n

\n

Removal of sand, mud, and shell fragments<\/p>\n<\/td>\n

\n

Removal or sterilization of hazards inside the tissue<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Shellfish depuration<\/a> is a process that utilizes the physiological activities of live shellfish<\/a>, which is different from the process of washing shucked oyster meat. However, it is not a process that consistently removes all viruses, marine Vibrio, shellfish toxins, and heavy metals. To understand the process described by a supplier, one must examine not only the equipment name but also the treatment target, operating standards, and records before and after treatment.<\/p>\n

\"Photo<\/p>\n

Washing stage during the Eoriguljeot manufacturing process at Samsam Mulsan.
Photo credit: Samsam Mulsan<\/p>\n

Work and management items vary depending on the shell-opening method<\/strong><\/h2>\n

Live oysters are distributed with the shell attached. For half-shells, the condition of the remaining shell and shell fragments are inspected after opening, and for shucked oysters, the meat is washed and drained after complete shucking. Since the oyster meat comes into direct contact with knives, gloves, workbenches, and containers during shucking, operational hygiene must also be managed.<\/p>\n

In shucking operations<\/a>, hand hygiene, cleaning and disinfection of tools and food contact surfaces<\/a>, the flow of movement in areas handling raw materials and oyster meat, and the sorting of shell fragments and removal of discarded shells are managed. After shucking, the oyster meat washing, sorting, and draining<\/a> processes follow. However, the suitability of process water or hygiene levels cannot be assumed to be secured simply because the number of washes is high.<\/p>\n

Boiled products are managed up to cooling and handling after heating<\/strong><\/h2>\n

Processes after shucking vary depending on whether heat treatment is applied. The boiling stage is not applied to raw products. Boiled products are treated according to heating standards set to match the hazards to be managed and product characteristics. It is verified whether the product is heated evenly, how the heating status is confirmed, and how products that deviate from the standards are handled. It must also be confirmed whether hygiene is maintained during the cooling, sorting, and packaging processes after heating.<\/p>\n

Boiled<\/a> means the oysters have been heated, but it does not necessarily mean they are Ready-to-Eat (RTE) products. Whether additional heating is required must be confirmed by checking the final use, post-heating handling, product labeling, and process data together.<\/p>\n

Refrigerated and frozen products are managed according to their storage methods.<\/strong><\/h2>\n

For refrigerated products, time and temperature management from receipt to shipment and the basis for the expiration date are verified. For frozen products, the state before freezing, stacking method, and equipment operation standards are checked first. Subsequently, it is verified whether the specified product state has been reached, how it was handled from the completion of freezing to packaging, and whether frozen storage records are maintained. Procedures for handling deviations from management standards, such as temperature, are also required.<\/p>\n

IQF refers to individual quick freezing, while block refers to freezing in a mass, and these are separate from whether the product is raw or boiled. Since not all quick freezing means IQF<\/a>, the freezing speed and the form in which the product is frozen must be distinguished. In the packaging stage, it is verified whether the net weight\/drained weight, glaze, sealing status, lot, storage conditions, and instructions for use match the actual process.<\/p>\n

\"Interior<\/p>\n

Photo of the automatic small-packaging room provided by Samsam Mulsan.
Photo credit: Samsam Mulsan<\/p>\n

Product-specific processes are verified along with actual production records<\/strong><\/h2>\n

How the aforementioned processes are applied to a specific product can be verified by looking at the product specifications, process flow chart, and records of the same production lot together. The key is whether the records are linked from raw material receipt to processing, packaging, and shipment. The process flow chart distinguishes and indicates the stages the product goes through and those it does not.<\/p>\n

<\/p>\n