Chapter 10: Lipids: Nature's Flavour Enhancers Part 2

A mixture of a lipid and a H2O based liquid

Phospholipids because they have a polar end that attracts water and a nonpolar end that attracts the lipid

Butter, margarine, mayonnaise, bottled salad dressings

• Provide a concentrated source of E

• Give a longer feeling of fullness due to digestion time

• Help regulate body temperature

• Provide an energy reserve from lipids stored in adipose tissue

• Protect vital organs from injury

• Participate in cell production

• Transport vitamins A, D, E, and K

• Produce hormones, vitamins, and other secretions

• Provide essential fatty acids

• Linoleic acid, can become Omega-6

| - Linolenic acid, can become Omega-3

Corn, cottonseed, and soybean oils, as well as chicken

Canola and soybean oils, walnuts and fish

May slow the growth of plaque in arteries

8 ounces or more, we have to be careful for mercury

• Lipids are not polymers.

• They do not provide structure to food products.

• They cannot be dissolved in water.

Butter: butyric acid

| Beef fat: stearic acid

A bend, making it tough to pack together tightly

Because their trans confirmation (no bend) makes them linear

The high degree of unsaturated, must be eaten or frozen

1) Milkfats
2) Lauric acids
3) Vegetable butters
4) Oleic-linoleic acids
5) Linolenic acid
6) Animal fats
7) Marine oils

1) Differing Melting and Solidification Points
2) Nonpolar Molecules
3) Tendency to Deteriorate

Because most lipids are mixtures of different kinds of fatty acids. Since each fatty acid has a different melting point, the lipids in a mixture will melt at different temperatures.

Lipids are less dense that the water due to the shape of the fatty acid chain that creates space between the parts of the molecule - oil floats on water

An emulsifier

Because unsaturated oils contain double bonds, which are more likely to react than single bonds

Vitamins A,C, E

The temperature of lipids will continue to increase as heat is added, unlike water

185oC

315oC

Between 175 (or else soggy) and 205 oC (or else outside burnt inside raw)

To allow the starch in the batter to bind to the food

No, since it pulls water to the surface of the food (increase splattering), also lowers the smoke point of the oil and will reduce the time the oil can be used

Fats aid in giving these products a fluffy, moist, texture. The separating of the flour keeps the products tender.

No, oils cannot provide the structure needed to trap air, which will result in a grainier texture

Because beating increases friction, it increases the batter temperature. If the temp goes too high, the fat will melt and the trapped air will be lost. This results in a crumbly, grainy texture

No, since the whipped stick just has extra volume due to trapped air. They are good to help lower fat in the diet though

Lecithin (phospholipid) found in egg yolk

| Butter, milk, and bottled salad dressings

Strengthen brain-cell membranes improving cell-to-cell communication. They may also reduce joint inflammation and prevent heartbeat irregularities and mental decline.

1) Used to produce hormones

| 2) Build cell membranes

• Too much cholesterol in the blood

• Lipid and cholesterol deposits on artery walls (plaque)

• Rough, rigid, narrow arteries = atherosclerosis, high blood pressure + heart attacks/strokes

LDL: Less than 100mg/dL
HDL: more than 40mg/dL (men) and 50mg/dL (women)

ONLY in animal sources: meats, dairy products, egg yolks

• Very low levels of saturated fat (olive oil)

| - High number of MUFAs

PUFA: lowers LDL and HDL
MUFA: lowers LDL, without lowering HDL

1) Distinctive flavour

| 2) Low smoke point

only in animal products

Excess blood cholesterol leads to plaque buildup in arteries

• Reduce intake of saturated fat and cholesterol

• Regular exercise

• Maintain healthy weight

• Read food labels: limit trans, sat fats and added salt and sugar

Fat: 20-35% daily calories

| Mostly from PUFAs and MUFAs

Fat: 20-35% daily calories

| Mostly from PUFAs and MUFAs

Lipoproteins

Healthy: HDL

| Not healthy: LDL

carry cholesterol to the liver

find unneeded cholesterol and return it to the liver