Dr. Thomas J. Montville 1
LIPIDS
Dr. Thomas J. Montville 2
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
Dr. Thomas J. Montville 3
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
Dr. Thomas J. Montville 4
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
Dr. Thomas J. Montville 5
Bad Things About Fat
• Makes you fat!• Heart disease, high blood pressure, cancer• Unsaturated fats are reactive free radicals
Dr. Thomas J. Montville 6
Stop and discuss carbon chemistry
Dr. Thomas J. Montville 7
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.
Dr. Thomas J. Montville 8
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
Dr. Thomas J. Montville 9
Fat Structure2. Monounsaturated Fat
Sources: avocado, peanuts, peanut butter, olive/olive oil
Dr. Thomas J. Montville 10
Trans fats, what were they thinking?
Polyunsaturated > monounsaturated
Dr. Thomas J. Montville 11
Trans Fats
• Time Article “Fessing Up to Fats”
Dr. Thomas J. Montville 12
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.”
Dr. Thomas J. Montville 13
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.
Dr. Thomas J. Montville 14
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
Dr. Thomas J. Montville 15
Nutritional Overview of Lipids
Dr. Thomas J. Montville 16
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
Dr. Thomas J. Montville 17
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
Dr. Thomas J. Montville 18
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
Dr. Thomas J. Montville 19
Dr. Thomas J. Montville 20
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
Dr. Thomas J. Montville 21
Fat Substitutes
• Olestra– Indigestible– Lack of ADEK– Digestive issues– Anal leakage
Dr. Thomas J. Montville 22
“On the seventh day of Olestra…”
Dr. Thomas J. Montville 23
http://www.zug.com/pranks/olestra
+ =
Day 1 Day 3 Day 5 Day 7
Dr. Thomas J. Montville 24
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
Dr. Thomas J. Montville 25
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
Dr. Thomas J. Montville 26
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
Top Related