Seafood Types & Qualities PDF

Seafood refers to aquatic animals used as food. They include the marine animals from the sea and those found in inland bodies of water. 1. Vertebrates or Finfishes - these are generally classified as: Round fish that live near the sea such as cod, haddock, and whiting. Flatfish such as sole and pla...

Seafood refers to aquatic animals used as food. They include the marine animals from the sea and those found in inland bodies of water. 1. Vertebrates or Finfishes - these are generally classified as: Round fish that live near the sea such as cod, haddock, and whiting. Flatfish such as sole and plaice. Pelagic fish or ocean fish caught in the open sea such as "fat fish" like mackerel, and cream dory. Fat fish have oil all over their bodies in contrast to lean fish whose oil is concentrated in the liver. 2. Shellfish - this type of seafood has hard shells outside protecting their soft tissues: Crustaceans such as crabs, lobsters, and varieties of shrimps. They have hard protective coverings called chitinous armor. This covering is segmented, giving them the ability to move and walk. Mollusks have soft, unsegmented bodies. These bodies are protected in calcified shells. Some mollusks have two shells, others have one. Those with two shells are called bivalves such as tahong (mussel), talaba (oysters), clams, and abalone, whereas single-shelled mollusks are called univalve such as all kinds of edible snails (suso). 3. Invertebrates - these are aquatic animals without a backbone. Some examples are octopus, squids, and related species. Structure, Composition, and Nutritive Value The flesh of the fish consists of: 1. Muscular tissues - these are bundles of white muscle fibers. 2. Connective tissues - these are found in between muscle fibers and are called mycommata. They contain the protein collagen which swells, shrinks, and becomes soluble. 3. Fat - most fish have their fat stored and reserved for energy. Fat content varies with season, feeds given to them, the size and age of fish. Fish classified by their fat content include: fat fish contains fat ranging from 5% to 20% medium-fat fish - contains fat ranging from 2% to 5% lean fish has less than 2% fat Fish deteriorate faster than meat because of the bacteria and fish enzymes in their intestinal organs which eat the neighboring flesh of the fish after rigor mortis. Rigor mortis is characterized by the stiffening of the muscles of the fish, making it rigid or hard. When rigor has passed, spoilage of the fish starts. Typical finfish have these parts: The typical finfish has up to 84% moisture, 15% to 25% protein, 0.1% to 5.7% fat, and 1% to 3.5% ash (Food Composition Table of the Philippines 1997, FNRI, DOST). Fish Sources and Fish Culture 1. Marine fish - these are fish obtained from saltwater, mainly the sea. 2. Inland fish - these fish are caught in lakes, rivers, ponds, and other inland bodies of water. 3. Aquaculture - this is the cultivation of some marine fish in inland waters in man-made fish pens such as the fish pens in Laguna Lake, Bangus or milkfish is cultured in fish pens and in fishponds. 4. Mariculture - this is the culturing fish in bodies of saltwater such as those in coves and shores. Examples of these kinds of seafood are tahong (mussels) and talaba (oyster). This type of culture has not yet been popularly adopted. Good Qualities of Fresh Fish When purchasing good-quality fresh fish, keep in mind that it should have: (a) a mild seaweed like odor; (b) shiny and tight skin; (c) bright red gills; (d) clear, full eyes; and (e) a firm body. Good Qualities of Other Seafood 1. Shrimps a. tight intact head b. transparent, firm body c. slight seaweed odor 2. Squids a. bright color b. firm body c. plenty of ink 3. Shellfish (clams, mussels, oysters) a. clean and fresh b. shells tightly closed c. shucked oysters - plump, creamy white, odorless 4. Crabs a. heavy b. slight seaweed smell c. shell corners are compact and very thin 5. Lobsters a. dark blue when alive b. spongy tails and deep-red shells when boiled C. male lobsters have a brighter color and larger claws d. female lobsters have broader tails and tenderer flesh Market Forms of Fish 1. Live Fish - good examples of these are dalag (mudfish), hito (catfish), tilapia, and hipon suahe (shrimp). However, this type of shrimp does not live long. 2. Whole or Round - the fish is not alive anymore, but the head, tail, fins, and viscera are still attached. 3. Drawn Fish - the fish has been eviscerated. Evisceration is done by making a slit down the center of the soft belly and removing the entrails. 4. Dressed Fish - the fish has been eviscerated. The scales, fins, head, and tail have also been removed. 5. Steak - this is a cross-section of fish obtained by cutting directly across the length of a dressed fish at right angles. Steaks cut are about one-half to two-thirds inch in thickness. 6. Split Fish - this is a whole or round fish with the scales intact but with a cut down the backbone from just behind the head toward the tail, splitting the fish into two wings or flaps. A palm is placed on top of the head of the fish to steady the fish before a knife is turned flat and the cut in made. 7. Deboned - this is the process of removing the big and small bones of a fish so that what is left is practically all flesh and skin. This process is gaining popularity especially among children who refuse to eat fish because it is quite cumbersome to remove the bones one by one as one eats. One popular fish that is deboned in the market is bangus (milkfish). The process involves the use of a pair of tweezers or clinical forceps to remove all the intramuscular bones especially those near the tail. The deboned bangus is available fresh, frozen, smoked, marinated, and ready-to-cook. 8. Fillet - this is the fleshy part of the fish. It is removed from the backbone and ribs of the fish so it is practically boneless. The skin of the fish may or may not be removed. 9. Butterfly Fillet - this is two fillets that are joined together by the underside skin. 10. Sticks - these are small elongated chunks of the same size and thickness cut from the flesh portion of the fish. 11. Cubes - these are sticks that are cut further into small squares. Market Forms of Shellfish 1. Live - this includes crabs, clams, mussels, oysters, and snails. They are usually brought live and this is the sole indicator of their freshness. Female crabs have a rounded apron found in the middle of its underside, while male crabs have a narrow, more pointed apron. Female crabs usually contain more aligi or crab fat. 2. Whole - shrimps of all kinds and sizes are normally bought whole but not alive, though the suahe shrimp can stay alive for some time. The big shrimps called sugpo (prawns) sometimes have their heads and thorax removed especially if they are to be transported abroad or in far places across the country. The heads are sold in the market and are boiled and eaten as is or they are ground and their juice extracted and sautéed with meat in making palabok sauce. 3. Shucked - oysters, clams, and scallops are sometimes sold in the market with their hard shells removed. Fresh shucked oysters appear translucent. 4. Cooked - some shellfish such as crabs, shrimps, and lobsters are already cooked in their shells and then marketed. Since shellfish do not stay fresh for long, it is better to cook as they keep longer before they are sold. 5. Cooked Meat - meat of crabs, shrimps, and lobsters are removed from their shell and steamed. It is then packed in vapor-proof plastic packages and sold in the frozen section of supermarkets or in open markets. 6. Shelled - most shrimps that are unsold are removed from their segmented shells. The meat is sometimes sprinkled with salt or washed in a brine solution to keep it fresh. Today, packaged shrimp meat is available in the frozen section of supermarkets. Preparing Fish and Shellfish A. Cleaning the Fish - Scaling 1. Soak the fish before scaling to facilitate the removal of scales. 2. Hold the fish with one hand and then scrape the scales off with a knife almost vertical to the fish from tail to head. Use scrapers with serrated edges or numerous blunt nails or soft drink bottle caps driven through a flat block of a small rectangular piece of wood with a handle. B. Cutting 1. Remove the head (as in the case of a large fish) by cutting above the collarbone behind the gills and then slicing straight through the backbone or snapping it off by bending it over the edge of the table. 2. Cut the pectoral fins together with the head. 3. Remove the dorsal fin by making vertical cuts down each side toward the backbone and then pulling it sharply toward the head (forward). 4. Cut the ventral fin in a similar manner (as the dorsal fin). 5. Remove the pelvic fins by cutting the flesh that attaches them to the belly flaps. 6. Remove the tail with a chopping blow using a heavy knife. C. Eviscerating - To eviscerate, make a slit down the center of the soft belly, and with the use of your fingers in one hand, pull out all the entrails of the fish. D. Rinsing - Use clean, cool, running water to thoroughly wash the inside and outside of the fish. Allow it to drain before cutting. E. Slicing the Fish - Slice the fish according to one's preference. Some prefer a drawn fish or a dressed fish, others prefer it deboned, in steaks, in fillets, in sticks, or split. Preserving Fish salting Drying and Dehydration smoking fermentation freezing canning refrigerator vacuum packaging