Etiket Arşivleri: Fat

Experiment: Determination of Fat

Name of Experiment            : DETERMINATION OF FAT

QUESTIONS

  • What is the principle of soxhelet extraction apparatus?

The principle of soxhelet extraction apparatus is to occur an intermittent extraction with excess of fresh condensed solvent in a special sample tube with a siphon attachment. The sample is held in a porous filter container such as thimble, and extracted fat returns with the solvent when siphoned, but does not redistill with the solvent and condense back to the sample.

  • What is the function of lipids on human body?

  1. They are source of energy.

  2. They need for vitamins that melted in fat.

  3. They need for Linoleic acid, Linolenic acid and Arachidonic acid because of certain of them cannot be made by the body. Essential fatty acids in lipids form part of the structure of all cell membranes.

  4. They preserve to body from out effects.

  • Define extractable fat and total fat.

  1. The extractable fat: The extractable fat is crude fat. It can be extracted by les polar solvents. Also, its amount is too much than other matters in food.

  2. The total fat: The total fat content consists of the additional ‘bound’ lipids which require more polar solvents (alcohols) for their extraction.

  • What is the function of acid added to the sample prior to the extraction?

The function of acid added to sample prior to the extraction is dissolved to proteins in lipids.

Extraction And Determination Of Crude Fat From Plant And Animal Tissues ( Ms. Nadia Amara )

Extraction And Determination Of Crude Fat From Plant And Animal Tissues

Ms. Nadia Amara

Introduction of Crude Fat :

Determination of Crude Fat is the term used to refer to the crude mixture
of fat material present in a sample.

Crude fat is the traditional measure of fat in food products.

Fat is important to all aspects of meat production and processing.

Lipids/fats are relatively non-polar molecules, they can be pulled out of a
sample using relatively non-polar solvents. (With a non-polar solvent, only
non-polar molecules in the sample dissolve while polar ones do not ).

The lipid materials may include triglycerides, diglycerides, monoglycerides, phospholipids, steroids, free fatty acids, fat soluble vitamins, carotene pigments, chlorophylls, etc.

Crude fat content is determined by extracting the fat from the sample using
a solvent, then determining the weight of the fat recovered.

The common approach for total crude fat determination is based on the
solubility of lipids in non-polar organic solvents such as hexanes, petroleum
ether, or other non-polar solvent .

In this lab we will determine the crude fat extracted by petroleum ether
solvent .

This method is applicable to extractions of oilseeds, meats, feeds, and foods.

Calculation :

Crude Fat % ( % of Dry matter) = (weight of crude fat + weight of extraction
flask )-(weight of extraction flask) / weight of sample *100

Principle of Soxhlet extraction :

Soxhlet extraction is a continuous solid / liquid extraction.

A solid which contains the material to be extracted is placed in what is called a thimble.

A thimble is made out of a material which will contain the solid but allow liquids to pass through. A lot like filter paper.

The thimble containing the material is placed in the Soxhlet extractor.

An organic solvent is then heated . As it boils its vapors rise up and are
condensed by a condenser. The condensed solvent then fills up the thimble,
and after it fills with enough solvent it automatically siphons back down
into the container of organic solvent.

This process takes place over and over again until all the material to be
extracted from the solid in the thimble is now extracted into the organic
solvent.

This cycle may be allowed to repeat many times, over hours or days.

The advantage of this system is that instead of many portions of warm solvent being passed through the sample, just one batch of solvent is recycled.

After extraction the solvent is removed, typically by means of a rotary evaporator, yielding the extracted compound. The non-soluble portion of the extracted solid remains in the thimble, and is usually discard.

1: Stirrer bar/anti-bumping granules

2: Still pot (extraction pot) – still pot should not be overfilled and the volume of solvent in the still pot should be 3 to 4 times the volume of the soxhlet chamber.

3: Distillation path

4: Soxhlet Thimble

5: Extraction solid (residue solid)

6: Syphon arm inlet

7: Syphon arm outlet

8: Reduction adapter

9: Condenser

10: Cooling water in

11: Cooling water out


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)


FE 272 Food Chemistry Lab Questions Exp 2 ( Kenan ÖZ )

Name of Experiment            : DETERMINATION OF FAT

Number of Experiment       : 2

Submitted by                           : Kenan ÖZ

QUESTIONS

  • What is the principle of soxhelet extraction apparatus?

The principle of soxhelet extraction apparatus is to occur an intermittent extraction with excess of fresh condensed solvent in a special sample tube with a siphon attachment. The sample is held in a porous filter container such as thimble, and extracted fat returns with the solvent when siphoned, but does not redistill with the solvent and condense back to the sample.

  • What is the function of lipids on human body?

  1. They are source of energy.

  2. They need for vitamins that melted in fat.

  3. They need for Linoleic acid, Linolenic acid and Arachidonic acid because of certain of them cannot be made by the body. Essential fatty acids in lipids form part of the structure of all cell membranes.

  4. They preserve to body from out effects.

  • Define extractable fat and total fat.

  1. The extractable fat: The extractable fat is crude fat. It can be extracted by les polar solvents. Also, its amount is too much than other matters in food.

  1. The total fat: The total fat content consists of the additional ‘bound’ lipids which require more polar solvents (alcohols) for their extraction.

  • What is the function of acid added to the sample prior to the extraction?

The function of acid added to sample prior to the extraction is dissolved to proteins in lipids.

Crude Fat Determination – Soxhlet Method

Fat is important to all aspects of meat production and processing. Fresh and frozen meat prepared for manufacturing purposes is specified in terms of fat content (expressed as chemical lean). This is an important specification of commercial trading as well as being an important technical specification for product end-use. Manufacturing meat that is traded as a commodity on the international market is specified in terms of its fact content (expressed as chemical lean) and this is one of the primary product testing criteria for product imported by our overseas customers.

Apart from the commercial importance of the fat content of unprocessed meat, especially manufacturing meat, fat content is an important technical and regulatory specification for almost all processed meat products.

There are several rapid methods for determining the fat content of meat and meat products and these methods mostly produce results that are sufficiently accurate and reliable for routine product testing purposes. Given the importance of fat content however as a commercial and

Laboratory‎ > ‎Fat Content

In this experiment we determined the fat content of cips sample. We used some apparatus and suitable organic solvent for fat determination. Organic solvents can be used to extract fat from food products. Many fat methods are based on extracting the fat with these organic solvents.Fat content is important for food products.

‎Laboratory‎ > ‎Fat Determination

In this experiment we determined the fat content of cips sample. We used some apparatus and suitable organic solvent for fat determination. Organic solvents can be used to extract fat from food products. Many fat methods are based on extracting the fat with these organic solvents.Fat content is important for food products.