Dr. Thomas J. Montville1 LIPIDS. Dr. Thomas J. Montville2 Our plan for the day… Good things about...

Dr. Thomas J. Montville 1

LIPIDS


Our plan for the day…

• Good things about “fat”• Bad things about “fat” • Lipid Chemistry (ugh) • Carbon chains can be saturated or

unsaturated, cis or trans • Problems with saturated and trans fatty acids


Good Things About Fats• Concentrated energy source• Stores energy for long term use (fat cells) • Flavor carrier • Heat Transfer - frying• Imparts texture – plasticity, flakiness• Mouthfeel – creamy, smooth


More good things about fat

• Essential fatty acids (linoleic, linolenic)• Phase transition (solid ↔ liquid)• Carries fat soluble (A,D,E,K) vitamins• Satiety- gastric inhibitory protein• Major component of membranes


Bad Things About Fat

• Makes you fat!• Heart disease, high blood pressure, cancer• Unsaturated fats are reactive free radicals


Stop and discuss carbon chemistry


Fat Structure

Fatty acids are either saturated, monounsaturated (contain one C=C double bond) or polyunsaturated (contain two or more C=C double bonds)

Saturated fatty acids stack closely and are more solid. Unsaturated fatty acids are more fluid. “Hydrogenating” unsaturated fatty acids makes them more rigid.


Fat Structure

3. Polyunsaturated Fat - Primarily plant sources: vegetable oils (corn, safflower, soybean, sunflower, canola, etc.), margarine (most), mayonnaise, certain nuts (almonds, filberts, pecans, walnuts)Animal Sources: fish

1 Saturated Fat – Primarily animal sources: meat, poultry, milk, butter, cheese, egg yolk, lardPlant Sources: chocolate, coconut, coconut oil, palm oil, vegetable shortening


Fat Structure2. Monounsaturated Fat

Sources: avocado, peanuts, peanut butter, olive/olive oil


Trans fats, what were they thinking?

Polyunsaturated > monounsaturated


Trans Fats

• Time Article “Fessing Up to Fats”


Trans Fat• Men’s Health Article “The Hidden Killer”• “It’s a fat that’s difficult to digest so it increases

the amount of bad cholesterol in your blood and can dramatically boost your risk of heart disease. If saturated animal fats are unhealthy, trans fats are far worse.”

• “You’re almost better off eating butter and bacon.”

• “Harvard scientists estimate that trans fats may contribute to more than 30,000 premature deaths per year.”

http://www.menshealth.com/cda/article.do?site=MensHealth&channel=health&category=heart.disease&conitem=88f999edbbbd201099edbbbd2010cfe793cd____


Linolenic Acids

Alpha – linolenic acid (omega 3)

Structure of omega-3 fatty acids and omega-6 fatty acids. These fatty acids are defined by the location of the first double bond.


Summary of FatsSaturated Unsaturated

Single bond (straight) Double bond (kinked)Solid LiquidAnimal (cholesterol) Plants (cholesterol free)Flaky Tenderization“Unhealthy” Essential Fatty Acids

and ώ-3sChemically stable D.B.s reactive, free

radicalsCooling as Solidliquid


Nutritional Overview of Lipids


Nutritional Overview

• Functions– Provide energy – Serve as energy reserve– Assist in transport and adsorption of fat-soluble

vitamins– Serve as source of essential fatty acids – Insulate and protect organs – Maintain cell walls and play role in making

Vitamin D


Nutritional Overview

• Food Sources– Oils, sauces, spreads, butter– Meat, poultry, fish, eggs, nuts (fish oil for omega 3s)– Milk, cheese, dairy– Breads cereals and grains with added fats

• Recommended Intake– Less than or equal to 30% of calories from total fat– Less than or equal to 10% of calories from saturated

fat – No more than 300 mg cholesterol


Fats In Food •Milk: (8 oz. serving)

•Whole: [3-4 % (legal 3.2%)] 150Kcal•2%: 120 Kcal•1%: 100 Kcal•Skim: [<.5%] 90 Kcal

•Cream:•Heavy (Whipping): 36% •Light: 18%•½ & ½ : 10.5%

•Others:•Mayo: 65% oil, vinegar, sugar, salt, egg yolk•Salad Dressing: 40% oil


Fat Substitutes

• Simplex– Egg white and milk protein– very small 0.1 – 0.3uM – microencapsulated

• Oatrium – from oat bran or flour• Avicel – microcrystalline cellulose (from wood)

(0 calories)• Olestra (Olean) polyester sucrose


Fat Substitutes

• Olestra– Indigestible– Lack of ADEK– Digestive issues– Anal leakage


“On the seventh day of Olestra…”


http://www.zug.com/pranks/olestra

+ =

Day 1 Day 3 Day 5 Day 7


Take Home: Fats, Oils, Lipids

• Good things about fats – Concentrated source of energy 9 cal/g– Flavor carrier– Imparts texture– Imparts mouthfeel, phase transiition– Carries fat soluble vitamins, ADEK– Major component of membranes – Satiety


Take Home: Fats, Oils, Lipids

• Bad things about fats:• Saturated – solid, animal, leads to cholesterol• Unsaturated, polyester sucrose,

non-digestible, loss of ADEK– Makes you fat– Coronary disease– Heart disease– Cancer


Take Home Points• Know the good and bad characteristicsof fats and oils

• Saturated vs. unsaturated – where found, why used– cis vs. trans

• Fat in Food– How much?– What foods?– Different types of oil (general)– Fat free does not equal calorie free

• Fat Substitutes

Dr. Thomas J. Montville1 LIPIDS. Dr. Thomas J. Montville2 Our plan for the day… Good things about...

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