answersLogoWhite

0

EXPERIMENT NO. 3

EXTRACTION AND ISOLATION OF PECTIN FROM CITRUS PEELS

Introduction

Pectins are polysaccharides composed mainly of polymers of D-galacturonic acid whose monomers are joined by (1,4)-linkages. They also contain arabinose and galactose. The carboxyl group of galacturonic acid can be esterified to varying extents with methanol. The hydroxyl groups in the 2nd and 3rd positions menwhile can be acetylated to a lesser extent.

In strong acidic medium, the glycosidic linkages are hydrolyzed. Pectin is most stable at pH 3-4. In basic medium, the ester and glycosidic linkages are split to the same extent. The latter is eliminated because the hydrogen atom in theC-5 position is more acidic compared to the galacturonic acid with free carboxyl groups.

The degree of esterification is determined by the saponification of pectin followed by titration of the free carboxyl acid groups. The volumes obtained is used to calculate % methoxy content which is equal to the total mass of methoxy over the mass of the pectin sample multiplied by 100.

Procedure

A. Isolation

B. Determination of methoxy content

air-dried pectin

weigh not more than 0.25 g

+ 2.5 ml EtOH

+ 0.5 g NaCl

+ 100 ml CO2-free distilled water

+ 6 drops phenol redyellow solutiontitrate with 0.1 N NaOHpink solution(V1)+ 12.5 ml 0.25 N NaOH, shake

stand for 30 minutes at room temperature

in stoppered flask

+ 0.25 N HCl dropwiseyellow solution

titare with 0.1 N NaOHpink solution (V2)

User Avatar

Wiki User

14y ago

What else can I help you with?

Related Questions

What is the ratio of liquid to powdered pectin?

1 tbsp of liquid pectin = 2 teaspoons of powdered pectin


How do you use pectin in a sentence?

Pectin is a gelling that is used in jams and jellies. Pectin is extracted from citrus fruits.


Is pectin a monomer or a polymer?

Pectin is composed of polymers.


What are the differences between liquid pectin and dry pectin, and how do they affect the outcome of recipes that call for pectin as an ingredient?

Liquid pectin is a thick, syrupy liquid while dry pectin is a powder. Liquid pectin is typically added towards the end of the cooking process in recipes, while dry pectin is usually added at the beginning. The choice between the two can affect the texture and set of the final product, with liquid pectin often resulting in a softer set compared to dry pectin.


Can Pectin be found in pigs?

Is pectin a pork-by product? No. Pectin is made from fruit and used to stabilize jellies. http://en.wikipedia.org/wiki/Pectin Could a pig be found which has pectin in its digestive tract? Yes, if it was fed pectin.


What type of enzyme is pectin?

Pectin is not an enzyme but a soluble fiber.


Does pectin have gluten?

Yes, pectin mainly comes from apples.


Where can you find vegan jelly without pectin?

Jelly has to have pectin to be jelly. Pectin is vegan. It is a natural product found in fruit. You may be confusing pectin with gelatin which is made from animal products.


What is the chemical equation for pectinase?

The chemical equation for the breakdown of pectin by pectinase is: Pectin + H2O → Oligosaccharides Pectinase catalyzes the hydrolysis of pectin into smaller oligosaccharides by breaking the glycosidic bonds within the pectin molecule.


What is in no cook freezer jam fruit pectin?

Pectin. Pectin is a food-gum that comes from fruit that helps thicken jam when sugar is added.


Can you convert dry pectin to liquid pectin?

2 Options, Use A Hairdryer Or Put it In The Freezer


Is gelatin vegan?

Vegetarian substitute for gelatine is Pectin. Pectin is made from fruits.