Etiket Arşivleri: oil

Fats and Oils

Fat Is…

The most concentrated source of food energy

There are 9 calories in every gram of fat

Fats that are liquid at room temperature are called oils.

Fats that are firm at room temperature are called solids. 

In a 2,000 calorie diet…

It is recommended that the maximum number of grams of fat a person should have in a day is 66 grams. 

No more than 30% of a person’s total calories should come from fat sources. 

No more than 10% (22 grams) of the total fat should come from saturated fat

20% (44 grams) should be from monounsaturated and polyunsaturated fat sources

Calculating the Percent of Calories From Fat:

1.Take grams of fat and multiply by 9

2.Divide by total calories

3.Multiply by 100

EXAMPLE:

Honey Grahams

  • Serving Size = 2 crackers

  • Calories = 130

  • Protein = 2 grams

  • Carbs = 21 grams

  • Fat = 4 grams

What is Cholesterol?

Cholesterol is NOT fat. 

It is a “fat-like” substance present in all body cells that is needed for many essential body processes.

It contributes to the digestion of fat and the skin’s production of vitamin D. 

Adults manufacture all the cholesterol they need, mostly in the liver. 

All animals also have the ability to manufacture cholesterol.

Cholesterol In Foods

Because all animals make cholesterol, if you eat any animal product, including meat, poultry and fish, you will be consuming some “extra” cholesterol.

Other foods high in cholesterol are:

Egg Yolks

Liver / Organ Meats 

Some Shellfish

LDL’s and HDL’s

A certain amount of cholesterol circulates in the blood.  It does not float through the bloodstream on its own, but in chemical “packages” called lipoproteins.  There are two major kinds of lipoproteins:

1.LDL’s (Low-Density Lipoprotein)

2.HDL’s (High-Density Lipoprotein)

Low-Density Lipoproteins

Takes cholesterol from the liver to wherever it is needed in the body.

If too much LDL cholesterol is circulating, the excess amounts of cholesterol can build up in artery walls. 

This buildup increases the risk of heart disease or stroke.

Thus, LDL cholesterol has come to be known as “bad cholesterol.”

High-Density Lipoproteins

Picks up excess cholesterol and takes it back to the liver, keeping it from causing harm.

Thus, HDL cholesterol has come to be known as “good cholesterol.”

For most people, the amounts and types of fats eaten have a greater effect on blood cholesterol than does the cholesterol itself. 

The fats found in food, such as butter, chicken fat, or corn oil, are made up of different combinations of fatty acids. 

Types of Fat

Fatty Acids:

Organic acid units that make up fat.  There are three types…

1.Saturated

2.Polyunsaturated

3.Monounsaturated

Saturated Fatty Acids

Appear to raise the level of LDL (“bad”) cholesterol in the bloodstream

Food sources: meat, poultry skin, whole-milk dairy products, and the tropical oils-coconut oil, palm oil, and palm kernel oil. 

Polyunsaturated Fatty Acids

Fats that seem to lower total cholesterol levels.

Food sources: many vegetable oils, such as corn oil, soybean oil and safflower oil. 

Monounsaturated Fatty Acids

Appear to lower LDL (“bad”) cholesterol and help raise levels of HDL (“good”) cholesterol. 

Food sources: olives, olive oil, avocados, peanuts, peanut oil and canola oil.   

All fats include all 3 kinds of fatty acids, but in varying amounts. 

Each type of fat has a different effect on cholesterol levels

Other “Essential” Fatty Acids

1.Linolenic Acid

2.Linoleic Acid

A Good Rule of Thumb…

Fats that are solid at room temperature are made up mainly of saturated fatty acids.

Fats that are liquid at room temperature are made up mainly of unsaturated fatty acids.      

Hydrogenation

The process in which missing hydrogen atoms are added to an unsaturated fat to make it firmer in texture. 

This forms a new type of fatty acid called trans fatty acid.

Trans fatty acids have many of the same properties as saturated fats.          

Visible Fat

Fat that is easily seen

Examples:  Butter on a baked potato, layer of fat around a pork chop, etc.

Invisible Fat

Fat that cannot be detected by the eye

Examples:  whole milk, some cheese, egg yolks, nuts, avocados, etc. 

Functions of Fat

Supplies Energy

Carries Vitamins A, D, E and K through the body

Provides a reserve store of energy

Promotes healthy skin

Promotes normal cell growth

Acts like a “cushion”and heat regulator to protect your heart, liver and other vital organs

It helps you feel full longer

Adds flavor to food

Too Much Fat…

Americans eat not only too much fat, but the wrong kinds of fat.  Doing so can increase the risks for serious health concerns and illnesses. 

High fat diets are linked to…

Heart Disease

Obesity

Cardiovascular Related Problems

Lowering Fat and Cholesterol in the Diet

Exercise

Replace saturated fats with unsaturated fats in the diet

Choose lean cuts of meat

Steam, boil or bake foods instead of cooking them in oil or fat

(See the last page of your handout for more tips)

Esterification

Esterification

Introduction:

Esters are a class of organic compounds which, unlike many organics, have pleasant odors. In fact, many of the "artificial flavors" used in food products are very pure esters. Esters occur naturally but can also be synthesized in the lab. To synthesize an ester, you must start with two other organics – an alcohol and an acid. The alcohol and the acid react to form the ester and a water molecule. Some esters that can be easily synthesized include methyl salicylate (oil of wintergreen), isoamyl butyrate (pear), isoamyl acetate (banana), ethyl acetate (fruity), and methyl acetate (sweet smell).

Purpose:

To synthesize and identify organic esters.

Materials/Equipment:

microscale kit sulfuric acid (conc.)

250 mL beaker acetic acid, glacial

hot plate salicylic acid

thermometer isoamyl alcohol

4 styrofoam cups methanol

parafilm ethanol

Safety Considerations:

 Always wear goggles and an apron.

 Keep all reactants away from flames.

 Do not try to taste any of the esters.

 Use extreme caution with the concentrated acids.


Alternative 
Techniques 
for
 Edible
 Oil 
Refining ( Ege
 University Food 
Engineering Dept. )

Qualitative
 Objectives
 of
 Oil
 Refining

• Complete
 removal
 or
 reduction 
of
 undesired constituents
 to 
tolarable 
limits
 to
preserve quality 
attributes
 of 
oils.

• Removal 
of
 contaminants 
for
 food
 safety
(PAH, pesticides,etc.)

• Maximum 
retention
 of
 tocopherols
 and
 sterols
in refined
 oils

• Prevention
 of 
undesired 
reactions (conjugation, trans
formation
etc.) 
together 
with
elimination 
of process contaminants
 (3‐MCPD
 and
 esters)


Palm Oil Industry in Malaysia

Origin of Palm Oil

Global Palm Oil Industry

Palm Oil Value Chain & Applications

Palm Oil Benefits

Oil Palm Cultivation Area

Palm Oil Industry Against Economic Cycles

Palm Oil Production & Midterm Prospects

Economic Importance To Malaysia

History Of The Malaysian Palm Oil Industry

Oil Palm Introduction and Commercialisation

The oil palm tree was first introduced to Malaya by the British as an ornamental plant in 1875 but it was only commercially planted in Tennamaran Estate, Selangor 1917 by Henri Fauconnier.

Crop Diversification Efforts

Despite threats of the Emergency during the 1960s, the oil palm expansion in Malaysia was rapid as its economic potential was recognised by the Malaysian Government as a complementary crop to rubber in the poverty eradication programme. The Federal Land Development Authority (FELDA) first introduced the oil palm in 1961 on an initial size of 375 ha to help the landless farmers. Due to the fall in rubber and tin prices, estate planting of oil palm tended to be on old rubber estate land when the prospects of high yields and profitability of palm oil were recognised. In 1966, Malaysia overtook Nigeria as the world’s leading exporter of palm oil. Compared to Malaysia, the Indonesia government only started to directly invest in state owned plantations in 1968.

Export Diversification

Realising from historical experience with rubber and tin that dependence on narrow product lines can bring price downswings, the Malaysian government embraced diversification as a way to sustain production and exports.

Acting against the advice of international agencies, the Malaysian government began in the late 1970s to encourage a shift from CPO exports to refined products through taxation and incentive policies. The 1980s saw the “Malaysianisation” of 3 major plantation companies previously run by the British i.e. Sime Darby, Guthrie and Harrison & Crossfield (later Golden Hope Plantations) 1980 also saw the founding of the Kuala Lumpur Commodity Exchange (KLCE), a key instrument for price setting, hedging and dissemination of market information to reduce market risk in the trading of palm oil.

Characterization of Turkish Olive Oils by Using Multivariate Statistical Methods

Characterization of Turkish Olive Oils by Using Multivariate Statistical Methods
Aytaç S.GÜMÜŞKESEN, Fahri YEMİŞÇİOĞLU
İsmail EREN
Ege University, Engineering Faculty,
Food Engineering Department, İzmir- TÜRKİYE

INTRODUCTION

Virgin olive oil is a food with high nutritional qualities; hence, it is chosen for cooking and dressing by consumer from Mediterranean countries, which represent the world’s largest production area (98% of world’s olive oil).

Factors Affecting Olive Oil Composition

The flavor of extra virgin olive oil has particular desirable organoleptic and nutritional properties. However, chemical composition of the olive oil together with its physical and sensory characteristics mainly depends on several factors such as;

Olive variety

Environmental factors (soil, climate, growing location)
Agronomic factors (irrigation, fertilization)
Cultivation (harvesting method, maturity)
Technological factors (storage, extraction system)

 

Oil and Fat Technology Lectures 3 ( Dr. Aytaç SAYGIN GÜMÜŞKESEN )

OIL AND FAT TECHNOLOGY LECTURES III

(Crude Oil Production)

Prof.Dr.Aytaç SAYGIN GÜMÜŞKESEN
Yrd.Doç.Dr.Fahri YEMİŞÇİOĞLU

Extraction of Vegetable Oils

Basic approaches :
Mechanical Oil Extraction
– cold pressing means no heat applied
– hot pressing – external heat is applied
Solvent Extraction
– organic solvent (hexane, isopropyl alchool)
– supercritical solvent (carbondioxide)
Mechanical oil extraction
Mechanical oil extraction (expression) is a solid-liquid phase seperation method which is applied to cooked seed flakes.
It can be executed by batch, mainly hydraulically, and by continous, mainly mechanically, working presses.
Screw presses;
In oil industry, screw presses (expellers) are mostly utilized for expression. The main parts of continous-screw press are;
Seed feeder,
Cone-shaped cage
Adjustable cone for press-cake outlet
Worm (pressure and feed)

Oil and Fat Technology Lectures 4 ( Dr. Aytaç SAYGIN GÜMÜŞKESEN )

Refining of crude oil

Crude oils as received from the extraction plant contain several non-triglyceride components which must be removed.

Refining consists of several processes which accomplish this aim.

A refining process is carried out following extraction of crude edible oils by means of screw presses and/or solvent extraction.

In refining, physical and chemical processes are combined to remove undesirable natural as well as environmental-related components from the crude oil.

These components comprise for example phosphatides, free fatty acids, pigments (such as chlorophyll), odors and flavors (including aliphatic aldehyde and ketone), waxes as well as heavy metals,
pesticides etc.