Food categories and composition information

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Food categories and composition information. 14 categories defined by USDA as “commodities” red meat, poultry, fish/shellfish, eggs, dairy, beverage milks, fats/oils, fruits, vegetables, peanuts/tree nuts, flour/cereal products, caloric sweeteners, coffee, cocoa - PowerPoint PPT Presentation

Text of Food categories and composition information

  • Food categories and composition information14 categories defined by USDA as commoditiesred meat, poultry, fish/shellfish, eggs, dairy, beverage milks, fats/oils, fruits, vegetables, peanuts/tree nuts, flour/cereal products, caloric sweeteners, coffee, cocoathese include some processed foodsFood Guide Pyramid (1992) defined 6 categories from a nutritional pov now 5 with MyPlate (2011) Bread, cereal, rice, pasta (grains)Fruit groupVegetable groupMilk, yogurt, & cheese group (dairy)Meat, poultry, fish, beans, eggs & nuts group (protein)Fats, oils & sweets (no recommendation)

  • Food Guide Pyramid (1992)

  • New for 2011 at:http://www.choosemyplate.gov/food-groups/

    New nutritional guidelines:five categories recommended for balanced daily consumption

    Can click on each category for description of whats included, how much to eat, health/nutritional benefits

  • Where to find composition informationComposition of recognized nutrients in a given food/beverage can be found in USDA National Nutrient Database http://www.nal.usda.gov/fnic/foodcomp/search/To search the content of specific constituent across many foods, access nutrient lists at: http://www.ars.usda.gov/Services/docs.htm?docid=22114Databases on certain foods like flavonoids that are extensively researched are re-released periodically: http://www.ars.usda.gov/Services/docs.htm?docid=6231Manufactured products are required to use Nutrition Facts labelingData given per serving Total fat, carbohydrate, protein, cholesterol, sodium, vitamins & minerals by weight & RDAMay list other constituents but not a complete list

  • Searchable nutrition facts database for produce and products at http://www.nutritiondata.com/For more specific information on phytochemical composition USDA databases (recognized nutrients)Scientific literature (all phytochemicals)AGRICOLA database (link from UMD library site), can search National Agricultural LibraryScifinder Scholar database searches CAS online for chemistry literaturePubmed studies on health/nutrition Journal of Agricultural and Food ChemistryWhere to find composition information

  • Nutritional & Health Studies and Industry NewsNutraingredients-USA: nutrition & supplements news (http://www.nutraingredients-usa.com)Food Navigator: food & beverage news Europe(http://www.foodnavigator.com/)USA (http://www.foodnavigator-usa.com/)Can search by topic, ingredient, health conditions

  • 2 slices Dominos deep-dish cheese pizza, as reported by NutritionData.com

  • A word about organic foodsCertification requirements and farming practices vary worldwide but generallyGrown without synthetic pesticides/herbicides or fertilizersProcessed without irradiation or chemical food additivesNot genetically modifiedFor animal products, pesticide-free feed and no antibiotics or growth hormones

  • But are organic foods better for you?2012 study: Smith-Spangler, et al, Annals of Internal Medicine 157: 348-366Meta-analysis of 17 human and 223 studies of nutrient & contaminant levels in foods between 1966 and 2011Conclusion: published literature lacks strong evidence that organic foods are significantly more nutritious, but they may reduce exposure to pesticide residues and antibiotic-resistant bacteria.

  • Natural food constituents classified by chemistry & physiological rolesCarbohydrates energy storageLipids (fat/oil) energy & structuralAmino acids and proteins structural & regulatoryLipoproteins, glycoproteins, etcspecialized rolesWaterVitamins and co-factors - catalysisMinerals Plant secondary metabolites or phytochemicalsRoles in plants are many defense, propagation Can be classified into subcategories based on biosynthetic pathway and structurestructural similarities exist among members of a genus (e.g. Vaccinium berries)

  • Cereals, grainsCorn, rice, wheat, barley, rye, oats, millet, sorghum, etcKernels (seeds) used (endosperm, bran & germ)http://www.choosemyplate.gov/food-groups/grains.htmlContain primarily carbohydratessimple sugarsdisaccharidespolysaccharides: amylose/amylopectin (starch) and cellulose (undigestible = fiber)Fiber may be insoluble or soluble in water, structurally complex moleculesRatio of simple:complex carbs variesProtein, fat and mineral content variesVitamins/minerals may be added back if lost in processingPlant proteins are generally deficient in lysine & methionine from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • Essential amino acidsHistidineIsoleucineLeucineLysineMethioninePhenylalanineThreonineTryptophanValineCannot be synthesized by human body, therefore must be included in diet

    Complete proteins

    Body doesnt store a.a.s to a great extent, needs constantsupplyfrom: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • Meat, poultry & seafoodIts got a lot of protein and saturated fat but it can be tasty Furnishes all of essential amino acidsB vitamins, iron & other minerals too.Seafood is a bit more interesting from a health p.o.v. due to omega-3 fatty acid content in some fishstay tuned!

    from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • Fruits & vegetablesWhats the difference? Sugar content? Botanically speaking, a fruit is the ripened ovary of a plant, contains the seedsA vegetable is any other edible plant part: leaf, shoot, root, tuber, bulb, flower or stemTomatoes & squash are fruit!Composed mainly of water, carbohydrates, but high in vitamin content (esp. A & C)Secondary metabolite/phytochemical content is diverse USDA website lists categories of fruits and vegetables, some health benefitshttp://www.choosemyplate.gov/food-groups/vegetables.htmlhttp://www.choosemyplate.gov/food-groups/fruits.html

    from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • Legumes & nutsLegumes are edible seeds, pods of certain flowering plantsMainly from families Leguminosae, FabaceaeBeans, lentils, soybeans, peas, peanuts

    Tree nutsAre actually fruitsInclude almonds, walnuts, pecans, macadamias, etc. from various families

    Both legumes and nuts Have a high protein content compared to other plant-based foods (common nuts range from 8-38 g protein/cup)Legumes are deficient in lysineCarbohydrate composition may contain substantial fiber Good source of mineralsNuts are higher in fat, but mainly unsaturated

    from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • Dairy productsDerived primarily from cows milk but some other sources as wellWhole milk composition = 88% water, 3.3% protein, 3.3% fat, 4.7% carbspH = 6.6, high calcium contentMilkfats primarily saturated but contain fat-soluble vitamins A,D,E,K Major carb = lactose intolerance caused by lactase deficiencyMajor proteins = casein & wheycasein is coagulated out as curd by lowering milk pH to 4.6 with rennin, an enzyme used in cheesemakingwhey proteins can be pptd out by heat, isolated by filtrationwhey used as supplement and gelling agent

    from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

  • BeveragesNo one category Main ingredient is waterAlcoholSweeteners sucrose, high fructose corn syrup, artificialo Brix = wt % sucrose(g sucrose/100 g sample)measured by refractometry flavor depends on Brix:acid ratioNutrients?Phytochemicals?

    Water content of selectedbeverages

    Club soda 100%Iced tea100%Light beer95%Beer92%Cola89%Orange juice88%Red wine88%Vodka (90 proof)62%

    From Murano, UnderstandingFood Science & Technology (2003).from: Murano, P. Understanding Food Science and Technology, Wadsworth, 2003.

    *Why do lactose-intolerant people suffer so much discomfort? Undigested lactose creates lactic acid and other fatty acids that can be detected in a stool sample. Glucose may also be present in the stool as a result of undigested lactose. Lactase is normally produced in the small intestine. Dietary fiber cannot be digested either, but doesnt usually produce the same uncomfortable symptoms. This may be because of the differences in processing. Soluble fiber absorbs water to become a gelatinous, viscous substance and is fermented by bacteria in the digestive tract. Insoluble fiber has bulking action and is not fermented.