Fats and oils

By students of Sir Dr. M.S. GOSAVI COLLEGE OF PHARMACEUTICAL EDUCATION AND RESEARCH, NASHIK.

1. Fats and oils BY GROUP:8 ROLL NO:57-64

2. ROLL NO. NAME TOPICS COVERED 57 MALI DISHA INTRODUCTION 58 59 MARDA SIDDESH MATALE SHRUTIKA CHEMIICAL REACTION 61 MOGAL ANUJA SAPONIFICATION RANCIDITY 62 MOKAL ANKITA DRYING ACID VALUE SAPONIFICATION VALUE 63 MORE DIVYA ESTER VALUE IODINE VALUE ACETYL VALUE 64 MULE TEJAS RM VALUE USES

3. Introduction Fats and oils are the major part of the lipid present in the adipose tissue of mammals . Fats and oils are the esters of fatty acids and alcohols and on hydrolysis gives fatty acids and alcohols. Fats and oils are mainly the glyceryl esters of various fatty acids like palmitic, stearic, oleic, linoleic and linolenic. These are also called as triglycerides.

4. Fats and oils are of two types Simple- When the three fatty acids of triglyceride are same. Mixed- When the three fatty acids of trigylceride are not identical. Natural fats are mainly mixed glycerides and they do not have free acid or base (groups) so also known as neutral fats. Fats and oils are obtained from plants as well as from animals. A crude fat along with the glyceryl ester contains some amount of free fatty acids and 1-2% of unsaponifiable matter like sterols.

5. Difference between fats and oils. FATS OILS SOLID OR SEMISOLID AT ROOM TEMPERATURE LIQUID AT ROOM TEMPERATURE CONTAIN LARGE AMOUNT OF SATURATED FATTY ACIDS CONTAIN LARGE AMOUNT OF UNSATURATED ACID HIGH MELTING POINT LOW MELTING POINT FATS ARE ANIMAL FATS OILS HAVE VEGETABLE FATS FATS DO NOT CONTAIN DOUBLE BONDS OILS HAVE DOUBLE BOND FATS ARE MORE STABLE OILS ARE LESS STABLE Physical and Chemical Properties of Fats: Fat and oils are colourless or pale yellow in colour . These are insoluble in water and polar solvents but soluble in non-polar solvents such as ether, carbon tetrachloride and carbon disulphide

6. SIMPLE MIXED

7. Basic concepts in salt formation Salts are formed when a compound that is ionized in solution forms a strong ionic interaction with an oppositely charged counterion , leading to crystallization of the salt form In the aqueous or organic phase, the drug and counterion are ionized according to the dielectric constant of the liquid medium. The charged groups in the drug's structure and the counterion are attracted by an intermolecular coulombic force. During favorable conditions, this force crystallizes the salt form. All acidic and basic compounds can participate in salt formation However, the success and stability of salt formation depends upon the relative strength of the acid or base or the acidity or basicity constants of the species involved

8. The salt form is separated into individual entities (i.e., the ionized drug and the counterion ) in liquid medium, and its solubility depends upon the solvation energy in the solvent. The solvent must overcome the crystal lattice energy of the solid salt and create space for the solute. Thus, the solubility of a salt depends on its polarity, lipophilicity , ionization potential, and size. A salt's solubility also depends on the properties of solvent and solid such as the crystal packing and presence of solvates

9. Formation of halides A halide is a binary phase, of which one part is a halogen atom and the other part is an element or radical that is less electronegative (or more electropositive) than the halogen, to make a, e.g., fluoride, chloride, or theoretically tennesside compound. The alkali metals combine directly with halogens under appropriate conditions forming halides of the general formula, MX (X = F, Cl , Br or I). Many salts are halides; the hal - syllable in halide and halite reflects this correlation. All Group 1 metals form halides that are white solids at room temperature. A halide ion is a halogen atom bearing a negative charge. The halide anions are fluoride (F), chloride (CI), bromide (Br), iodide (1) and astatide (At). Such ions are present in all ionic halide salts. Halide minerals contain halides.All these halides are colourless , high melting crystalline solids having high negative enthalpies of formation.

10. Formation of esters: Fatty acids reacts with alcohol in the presence of a strong acid to form ester(triglycerides) 3 H3-(CH2)14-C=O + CH2OH -H2O CH2O CO(CH2)14CH3 HC O CO(CH2)14CH3 H2C OH H2C O CO(CH2)14CH3 Palmitic acid Glycerol Palm Oil OH HC OH

11. Reduction or hydrogenation: Unsaturated fatty acid undergoes reduction or hydrogenation in presence of reducing agents to form saturated fatty acid. OH 3HC-(CH₂)7-CH=CH-(CH₂)7-C=O Oleic acid H2 Ni OH 3HC-(CH2)7-CH2-CH2-(CH2)7-C=O Stearic acid

12. Saponification The alkaline hydrolysis of oil or fat (Glyceride) to form Soap (Alkali Salt of higher fatty Acid & glycerol is known as saponification. Reaction- Triglycerides are generally animal fats & Vegetable oils. When they are, reacted with Sodium hydroxide, a hard form of soap is created. Ester + Base Alcohol + Soap

13. Rancidity of oils Rancidity is the complete or in complete oxidation or hydrolysis of fats and oils when exposed to air, light, moisture or by bacterial action, resulting in unpleasant taste & odour . Types of Rancidity: Hydrolytic Rancidity :- In case of fats of oil the hydrolytic reaction will occur at the point where the fatty acids are connected to glycerol in triglyceride molecule.In fatty acids gets Split off from glylen forming a free fatty acids.

14. How to prevent Rancidity? To keep them away from direct sunlight or air. To keep them in Refrigerator Adding antioxidants.

15. Drying of oils When highly unsaturated oils are exposed to air, they undergo oxidation and polymerization to form a thin waterproof film. such oils are called Drying Oils and the reaction is referred to as drying Linseed oil which is rich in linolenic acid is a common drying oil used in oil based paints

16. Analytical Constants Acid Value: It is defined as the number of mg of koH required to completely neutralize Free fatty acids present in one gram of fat or oil. It is a measure of the free fatty acids present fat or oil Principle: It is determined by by titrating the sample of oil or fat in alcoholic medium F against 0.1 M KOH Formula: Acid value= 5.61 n/w Where n = burette reading W = sample weight

17. Significance Measure of acids breakdown of triglycerides into free. Fatty acids which has an adverse & undesirable effect Measure of degree of hydrolytic rancidity .

18. Saponification Value Saponification number is defined as the number of milligrams of KOH required to saponify one gram of Fat and oil Principle Saponification is the process by which the fatty aids in the triglycerides or fat are hydrolyzed by an alkali to give glycerol and potassium salts of fatty acids. A known quantity of fat or oil is refluxed with an excess amount of alcoholic KOH. After saponification the remaining KOH is estimated by titrating it against a standard acid. The value obtained is used for the determination of saponification no of fats and oil

19. Sample is titrated with with 0.5M HCI ( back reading, a ml). Perform blank titration (b ml) Saponification value = 28.05(b-a)/w Significance Gives an idea about the molecular weight of fat/ oil. smaller the saponification value higher the molecular weight Indicates the amount of alkali required for converting oil / fat into soap It also indicates the length of carbon chain of the acid present in that particular oil chain or fat.

20. Ester Value: It is the number of mg of KOH required to saponify the ester present in 1gm of the substances. Ester value = Saponification value - Arid Value Reaction:

21. Principle: It is determined by titrating the Sample of sil & fat in alcoholic medium against 0.5m Hcl . Formula: E.V=S.V-A.V Significance: The ester value shows the amount alkali consumed in the saponification of the ester and if possible identify and diffrentiate the fats with this value

22. Iodine Value: It is the number of grams of iodine that would add to C=C present in 100 g of the fats and ail. Reaction :

23. Principle: The oil / fat sample taken in Carbon tetrachloride is treated with a known excess of iodine monochloride Solution in glacial acetic acid. The excess of jodine monochloride is treated with potassium lodide . Now, this sample is titrated against 0.1M Sodium thiosulphate solution, starch solution used as a indicator for estimation of liberated iodine (A) and then perform blank titration (B) Iodine value =1.269(b-a)/w Formula:

24. Significance: The lodine value is a measure of the amount of double bonds ( unsaturation ) in a fats. Iodine Value = No. of double bond ↑ Unsaturated Lipids are more susceptible to rancidity

25. Acetyl value: It is the mg of KOH required to acetic acid liberated by the hydrolysis of 1g of the acetylated Substance Principle: It is determined through saponification value The process consists of acetylating the oil with a measured quantity of acetic anhydride in pyridine decomposing the excess anhydride by boiling with water and then addition in of sufficient butyl alcohol to give a homogenous solution titrating with alkali.

26. Significance: It is the measure of hydroxy OH acids in lipids Acetyl value = more amount of free fatty acids Formula: Acetyl value= 1335(b-a)/(1335-a) Where, a= saponification of the substance b= saponification value of the acetylite substance

27. Reichert- Meissl number [Reichert Meiss (RM) value] It is defined as the ml of 0.1 N KOH required to neutralize the soluble volatile fatty acids distilled from 5 g fat. RM number is useful in testing the purity of butter since it contains a good concentration of volatile fatty acids (butyric acid, caproic acid and caprylic acid). Butter has a RM number in the range 25-30, while it is less than I for most other edible oils. Thus any adulteration of butter can be easily tested by this sensitive RM number. Reichert Meissl RM value

28. Principle : Fat is saponified using glycerol-alkali solution & acidified by sulphuric acid to liberate free fatty acids. The liberated fatty acids are steam distilled and the steam volatile fatty acids are collected (as condensate). The cooled condensate of the volatile fatty acids is filtered for separation of water soluble and water insoluble fatty acids. The water soluble fatty acids is titrated with alkali to give RM value. Water-insoluble fatty acids is titrated to give the polenske value.

29. Significance: It is a measure of water soluble steam volatile fatty acids chiefly butyric and caproic acids present in oil or fat. No other fat contains butyric acid glycerides, and therefore, the Reichert Meissl value of the butter fat is higher than that for any other fat. These determinations have been used principally for analysis of butter and margarines.

30. USES OF FATS AND OILS : They are energy reservoirs and are more efficient proteins and carbohydrates. They are used in soap industries. They are used as raw materials for preparing higher alcohols used for manufacturing synthetic detergent. Groundnut oils are used for manufacturing Vanaspati ghee (marketed as Dalda , Rath , Gagan , etc.). Castor and cotton seed oils are used as purgatives. Cod liver oils are used in vitamin A and D deficiency conditions. They provides excellent insulation since fat is bad conductor of heat. Derived lipids are important building blocks of biologically active materials.