Ch. 9 & 11- Fish and Shellfish & Cheese PDF

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Fish and Shellfish & Cheese...

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March 2, 2021

Chapters 9 & 11: Fish and Shellfish & Cheese Chapter 9: Fish and Shellfish  Classification of Fish and Shellfish

o There are over 20,000 species of edible fish, shellfish and sea mammals. o FDA published Guide to Acceptable Market Names for Seafood Sold in Interstate Commerce in 1993, and require fish to be named according to this publication. o Classification is completed: According to the FDA publication, they maybe categorized by: Vertebrate v.s. invertebrate; saltwater vs freshwater; lean (5% fat) o Finfish: vertebrate; 

Finfish (obtain O2 through gills): tuna, cod, pollock, salmon, flounder; Shark (not mammal)

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Sea mammals (obtain O2 through air above water surface): dolphin, whale, seal.

o Invertebrates: external skeletons or shells. 

Crustacean: hard upper shell and a soft under shell

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Mollusk: soft unsegmented body enclosed in a shell (Abalone)

o Salt vs fresh: Normally salt water has more distinct flavor than fresh; Sole is an exemption, which have mild flavor. o Fish is usually tender than other meat. o Meat is delicate – poaching

o Fat: Fish is not fat comparing to other meats; o A good source of omega-3; o Fishy smell: oxidation of unsaturated fatty acids o Lean (5%)  Purchasing Fish and Shellfish

 Some have more omega 3 than others  Composition of Fish and Shellfish o Tenderness   

Less collagen (Land animal has ~15% of connective tissue by weight; Fish only has 3%) Less of the amino acid hydroxyproline (collagen breaks up easier) Shorter muscles - mytomes -> characteristic flaking

o Pigments: 

Fiber (in terms of muscle fiber)  Darker: slow-twitch fibers for long-distance swimming, like salmon  White: fast-twitch fiber for quick bursts, like sole  Tuna has both;

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Fat: higher fat content: darker; Myoglobin: darker = more myoglobin. However, it also becomes rancid faster because of the iron accelerate the oxidation of fat in the muscle.

 Purchasing Fish and Shellfish o Inspection is voluntary vs FSMA   

Department of Commerce is responsible for inspection FSMA: Seafood HACCP already exists, so minimal impact. FDA has requirement for preventive controls: sanitization of equipment, prevent of adulteration, employee training, etc. o Grading  Voluntary  Department of Commerce; National Oceanic and Atmospheric Administration (NOAA)  Only fish that are inspected can be graded  A, B, and substandard  A lot of seafood is harvest in international waters  Seafood is classified as the biggest risk for commodities for foodborne illnesses  General for finfish o Shellfish certification     

U.S. Department of Commerce Only from certified shippers can be sold Certified waters, which have been tested to be free of excessive level of microorganisms. DOC report violation to FDA, which has final jurisdiction over commerce in shellfish. Radiation safety: Fukushima, Japan. Dec 29, 2016, FDA issues an import alert to ban importation from Fukushima prefecture.

o Finfish (vertebrate) Taste can vary - Subtle difference in flavor among different 1. varieties of the same type of fish. e.g., Atlantic v.s. pacific salmon; almost all Atlantic salmon are farmed, because it’s an endangered species in the wild.

 Farmed have higher risks of contaminants  Color, taste, texture is different  Wild salmon is not safer than farmer, but the nutrition is better in wild  Atlantic salmon has to be farmed 2.

Sniff test and Translucent cornea (part surrounding the pupil)

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o o o o

Other criteria: tight scales, firm flesh, stiff body, red gills, belly free of swelling  Signs of decay in finfish ♦ Eyes become concave ♦ Pupil turns gray or creamy brown ♦ Cornea becomes opaque ♦ Gills turn brown 3. Rigor mortis gives best texture and flavor Lasts several hours to several days  Phosphate treatment can make fish slimy  Phosphate added to prevent moisture loss. (most fish is frozen and when thawed it loses moisture. Buy fish by pound, add moisture to add to profit)  Phosphate water increases pH (buffer) and denatures protein, make it more capable of binding water.  Fishery is weight-based profit  Without this, fish can lost 80% of its water binding capacity in 5 days after harvest.  It can also inhibit the oxidation of fat. Mercury contamination: pregnant women should avoid fish likely to contain mercury Methylmercury -> Industrial pollution -> airborne and fall into water. Almost all fish contain a minute amount of methylmercury. FDA recommendation - especially vulnerable - brain development -> pregnant women, nursing moms, young children.

 Pregnant/lactating women and infants shouldn’t consume these 4 fish because of the mercery  Can impair brain development

o Canned fish  Tuna, salmon, and sardines  Canned tuna: is associated with the mercury controversial. A consumer reports article advised pregnant women to avoid canned tuna entirely. -> industry loss revenue -> support research on health benefits of tuna -> non-pregnant adults - 2~3 serving per week. o Cured fish  Anchovies o Fabricated Fish

 Surimi (starch and pulverized white fish) o Caviar (roe)  Fish eggs. Highly perishable. High in cholesterol, high in salt.

o Beluga - the most expensive.

o Live shellfish (Lobsters and crabs have external skeletons, shells)  Lobsters  Crabs  Oysters  Clams o Selecting live shellfish  Tap shells

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The “R” month rule for safety: Only consume shellfish in months with the letter R. Because May-August, chances of having bacteria and foodborne illnesses are high. o Commonly purchased processed shellfish  Oysters  Clams  Scallops  Mussels  Abalone  Lobster  Shrimp, crab, and crayfish  Preparation of Fish and Shellfish o Dry-heat preparation  Baking  Broiling  Grilling  Frying  Sautéing  Deep-frying o Moist-heat preparation  Poaching  Simmering  Steaming  Clambakes: underground steaming  Microwaving

o Raw fish  Sushi vs. sashimi (w/ or w/o rice)  Ceviche - Fish prepared with marinade or lemon juice, which denature the protein, and turns to white color. o Raw fish carry risk of foodborne illness  Discouraged for pregnant women  Raw fish harbor worms

 Heating to 145 °F for 1 minutes  Storage of Fish and Shellfish o Fresh finfish should be eaten within 1-2 days  Store in coldest part of refrigerator  Wrap well  Put on ice o Caviar should not be left open for more than one hour o Eat fresh shellfish the day of purchase, if possible  Store in cool, salty, and wet environment o Many types of fish can be stored at 0° F for up to nine months  Best to thaw fish in the refrigerator o Unopened cans of fish can stay on the shelf for up to one year

Chapter 11: Cheese  Chapter Summary o Cheese is a preserved food made from the curd, or solid portion, of milk o One of the most nutrient-dense foods, cheese is most often used to add flavor, color, and texture to prepared foods o Important aspects of cheese for food preparation  Classification, production, purchasing criteria, and preparation and storage techniques  High protein, some high in fat  Cheese o Preserved food made from curd of milk o Making cheese  Drain whey (Remove moisture from curd)  Milk selection -> coagulation -> curd treatment (cutting, heating, kneading, etc.) -> curing -> ripening.  Coagulation -> Casein -> curd with most of the protein, fat, micronutrients from milk; Whey has most of the water, and some protein;  10 lb of milk ->1 lb of cheese + 9 lb of whey o Over 2,000 varieties of cheese  15 varieties account for most consumption  Either adding enzymes or calcium and change pH and starts to bind and coagulate  Classification of Cheeses o Ways of classifying cheese

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Milk source (cow, sheep, goat, etc.): pasteurized cow milk is the most common source in US. In EU and Middle East, Sheep or Goat milk is significant.  Fat content in cheese is determined by milk; (fat content is based on how the cheese is made and coagulated)  Homogenized milk is used for soft cheese -> coagulates more easily and uniformly. -> not suitable for hard cheese, because it will become brittle.  FDA requires all soft cheese use pasteurized milk.  Fermentation and ripening conditions  Methods of pressing, sizing, and shaping  Type of bacteria utilized  Appearance  Mode of packaging; place of origin  Moisture content  Comes to how to coagulate the cheese

 Different origins have different cheese o Moisture content in cheese classification  Fresh  Over 80% moisture content  Soft  50-75% moisture content  Semi-hard  40-50% moisture content  Hard  30-40% moisture content  Very hard  ~30% moisture content  Moisture determines the texture  Cheese Production o Cheese is usually produced by coagulating (clotting) the milk with either an enzyme or acid.

o Milk selection  Animal (cow, goat, sheep, camel, etc.)  Amount of fat (whole, 2%, nonfat) o Enzyme coagulation  Can come from a variety of sources  Chymosin/rennet (proteolytic enzyme) from animal stomachs  Fermentation-produced chymosin  Aspergillus  Kluyveromyces marxianus var. lactis  Produced by microbials not enzymes o Enzyme coagulation process  Rennet from Calf chymosin (enzyme that infant mammals produce to coagulate milk); Hydrolyzing Casin.  Coagulants: enzyme that’s derived from non-stomach courses. -> for vegetarians and adherents to kosher and halal.  Optimal temperature = 22~35 oC (72 to 95° F); Usually done in an hour;  Calcium chloride can be added to speed up the process. -> firm curd  Temperature too high can denature a protein  A lot of cheese is a substitute as calcium for production purposes o Acid coagulation  Two methods  First method: add acid directly to milk  Second method: Add lactose fermenting bacteria to produce acid. -> 4~16 hours -> soft and spongy curd.  More solid and compact as pH decreases.  Not aged, because acid prohibits the growth of bacteria.  Change pH and structure of the protein o Treating curd to remove more whey  Cutting

 Heating  Salting  Knitting  Pressing o Curing and ripening o Ripening: Stronger flavor. (involves mold)  Different temperature: 2~24 oC  4 weeks to 2 years; o Flavor: VOC and nonvolatile -> determined by milk, enzyme, starter microbe.

 Ripening/aging process mostly has to do with caseins  Aldehydes develop all sort of flavors, only found in fermented products (cheese, wine) o Whey - Low fat, and high nutrients. -> water soluble whey protein, lactose, water soluble vitamins and minerals.  Highly perishable.  Used to be animal feed. -> value-added research o Sweet whey: coagulates with enzymes o Acidic whey: coagulates with acid o Whey cheeses: primost, mysost, gjetost, ricotta o Dry whey (food for livestock, processed foods) o Modified whey products: condensed, protein concentrate, delactosed, demineralized  Whey are byproducts of cheese o Processed cheese was patented in 1916 by James Kraft, who funded Krafts.

 Purchasing Cheese o Not all graded. o But if graded, it’s based on variety, flavor, texture, finish, color, appearance

 Graded by the USDA, voluntary, not common o Forms of cheese  Blocks  Shredded or sliced  Individually wrapped sticks  Process cheese  Cheese powders  Sauce or dip  Food Preparation with Cheese o Selecting a cheese  Oiling off (phase separation)  Blistering (bubble) & browning  Shreddability  Meltability  Stretchability

o Cooking cheese  Low temperature; short cooking time o Serving cheeses  Semi-hard and hard: room temperature  Unripened cheeses: chilled o Cutting cheese  Triangular knife (very hard cheeses)  Skeleton knife or steel string (soft cheeses)  All-purpose cheese knife

 Storage of Cheeses o Dry storage  Process cheese spreads  Very hard cheeses (processed Parmesan) o Refrigeration  Store in original wrapper, in refrigerator door  Rewrap tightly (moisture loss)  Storage times vary by type of cheese

o Frozen: hard cheeses only  Refrigerate soft cheese...