Fish and seafood processing and packaging is a valued industry in America. Many types of seafood products are available in the U.S., from shellfish captured in the ocean to freshwater fish from lakes. After fish is caught, it must be processed and packaged to reach consumers as an edible product.
According to the National Oceanic and Atmospheric Administration (NOAA), Americans spent an estimated $102 billion for fishery products in 2017. Important species include salmon, halibut, tuna, lobster, shrimp, scallops, clams, crab, herring and oysters. Without the fish processing sector, many Americans wouldn’t have access to the seafood products they regularly enjoy. Processing is necessary to keep fish fresh long enough to reach the shelves in stores, restaurants and homes.
What Is Fish Processing?
Fish processing involves preparing fish and seafood for delivery to consumers. Once fish is harvested, it must undergo several steps before it’s ready to be sold in the market. The process includes gutting, filleting and packaging of the product. Fish is a highly perishable food, so it must be carefully handled from the moment it’s caught until it’s sealed in packaging material. Proper, efficient processing and packaging prevent deterioration and ensure a quality product.
How Are Fish Processed?
Fish processing generally involves the following steps:
- Sorting fish by size and species
- Loading fish into a machine to remove heads
- Moving fish to a cleaning machine to remove tails, scales and entrails
- Removing fins
- Washing thoroughly
Fish processing may be done manually or by the use of processing machines. The details of the process can vary greatly depending on a company’s size and the fish species they handle.
Manual vs. Automated
According to the Food and Agriculture Organization of the United Nations (FAO), freshwater fish are often manually processed, with employees using a wide variety of knives. Workers must be highly skilled to manually process fish efficiently and safely. In general, manual processing is more common in small processing plants.
Large plants require automated systems to yield abundant quantities quickly. Here’s a look at the different steps for both manual and automatic processes:
- Sorting and grading: Sorting fresh fish to classify species and check for damage and freshness is often a manual process. Grading fish size, on the other hand, is easily accomplished with machinery. Machine graders accurately and quickly sort fish. According to the FAO, automated grading is up to 10 times more efficient than manual grading. However, small plants often do not use automatic graders due to the cost of the machinery.
- Scaling: Scaling is another step that may be done manually, but it’s one of the hardest tasks because scales can be difficult to remove. Workers may scale fish using a hard brush or blade. Fish that are to be skinned or smoked do not need to be scaled. Some processing plants equip workers with electric handheld scalers. Electric scalers accelerate and simplify the process.
- De-heading: Freshwater fish may be de-headed manually. Usually, saltwater fish are de-headed on a machine. Manually de-heading large fish requires too much effort, and an automated de-heading machine must be used. De-heading machines typically use band saw blades, cylindrical knives or guillotine cutters.
- Gutting: The gutting of freshwater fish is also often done manually and is very labor-intensive. It includes cutting down the belly of the fish and removing the organs. A vacuum suction tool may be used to remove the entrails. Plants might utilize gutting machines to process certain species. Some machines provide an all-in-one solution and are capable of de-heading, cutting and removing the insides.
- Fin removal: Manual fin removal is a difficult process, particularly for large fish. An automated device made up of rotating disc knives accelerates the process.
- Slicing: Slicing fish into steaks is often done with a band saw. Large fish require mechanical slicing. There are many different types of slicing machines, such as ones that use several rotating circular knives. According to the FAO, a mechanical cutter can slice up to 40 fish a minute.
- Filleting and skinning: Plants might have a filleting machine that uses a rotating disc knife and conveyor belt to speed up the process. An automated tool for skinning consists of an oscillating knife powered by a small electric motor.
Quality and Safety for Fish Processing
One of the top concerns in the fish processing and packaging industry is spoilage. Fish quickly deteriorates, so steps must be taken immediately to extend shelf life. The process includes:
- Temperature control: Reducing the temperature to 32 degrees Fahrenheit slows down decomposition. Raw fish must be chilled in ice immediately after harvesting and be kept cool during the trip to the processing plant as well as throughout processing and distribution. Freezing is required to extend shelf life for a long time.
- Moisture control: Drying, salting and smoking reduces water content and makes a fish product suitable for consumption. Salting is a traditional method that’s often combined with drying and smoking. It’s also a low-cost way to preserve fish.
- Oxygen control: Fish may be vacuum-sealed to increase shelf life. Vacuum packaging deprives the fish product of oxygen, which prevents oxidation reactions and slows down spoilage.
- Microbial growth control: A processing plant might apply heat or increase acidity to kill bacteria and slow decomposition in fish products.
Waste management is another important aspect of fish and seafood processing. Treated fish waste can be turned into fish oil, animal feed, fertilizer and other value-added products. Fish waste must also be managed properly for environmental purposes.
Fish plants generate large amounts of waste. It’s estimated that more than 50% of fish captured are not used as food. Fish waste mostly includes:
- Internal organs
Fish processing also produces large amounts of wastewater. Liquid waste, such as discarded water from washing stations, needs to be managed and disposed of properly. The liquids must be assessed to determine the best disposal method.
Fish waste treatment may include methods such as hydrolysis, bioremediation, anaerobic digestion and filtration. Waste liquids undergo primary treatment, which removes materials that readily float or settle. Secondary treatment processes waste liquids after floating and settleable materials have been removed. Secondary treatment uses biological and chemical processes to change effluent and make it safer for the environment.
Packaging, labeling and distribution are the final stages of fish processing. Finished products may include:
- Fish fillets, steaks or loins
- Fish sticks or cakes
- Gutted whole fish, called drawn fish
- Scaled, gutted and ready-to-cook fish, or dressed fish
- Whole fish
- Shucked and cooked shellfish meat
- Fish roe
Edible products are packed as refrigerated, frozen or canned items. Products can also be sold for further processing. Secondary processors use fresh or frozen fish and seafood products to add to other ingredients and create various salads, sandwiches and meals found in restaurants and stores.
Seafood Packaging Types
Packaging serves two main purposes: to attract customers and preserve products. Food processing plants have a wide range of packaging options to choose from, but it mostly depends on the type of product they manufacture. Common packaging types include:
- Stand-up pouches: Attention-grabbing stand-pouches offer convenience, reduce packaging costs and keep products fresh.
- Cans: Canning has been a long-used method to preserve processed fish. Tuna, salmon and sardines are commonly canned after processing. A tin can is sealed and heated to keep air out and preserve the food inside.
- Vacuum skin packaging: Vacuum skin packaging (VSP) forms a tight, clear film over a product to enhance its visual appeal and extend its lifespan.
- Multi-layer films: Multi-layer films create a tight seal to keep fish fresh. This type of packaging shows the product clearly, and the multiple layers help protect packages from punctures and abrasions.
- Individually quick frozen (IQF) packaging: IQF packaging is often used for frozen fish fillets and other frozen seafood products. IQF is usually available in bag format and may come in a variety of styles, such as the pillow shape or flat bottom.
Packaging is often an automated process involving sophisticated machines that fill and seal product containers and bags. This process reduces the need for manual labor and speeds up the packaging stage.
York Saw and Knife Co, Inc. Plays a Large Role in Seafood Processing and Packaging
At York Saw and Knife Co, Inc., we proudly make blades used by automated machines that process fish and cut packaging. Our blades can be used for:
- De-heading, scaling, filleting, gutting and slicing machines
- Packaging cutting machines
- Custom solutions
If you don’t see what you need for your fish and seafood processing plant, remember that we can make custom blades for just about any application. To learn more about our seafood processing knives or request a free quote, call us at 1-800-233-1969 or contact us online today.