This document discusses extraction and filtration techniques used in food processing. It describes various extraction methods like maceration, percolation, and supercritical fluid extraction. These techniques are used to extract active constituents from foods. It also explains filtration principles and methods like bed filtration and microfiltration. Filtration separates solids from liquids using a porous medium. Various applications of extraction and filtration in food processing, pharmaceuticals, and environmental areas are provided. In conclusion, the document outlines the importance of extraction and filtration in the physical conversion of foods.

2. ☻ Introduction
☻ Food processing techniques
☻ Extraction
a) Mechanism
b) Methods
c) Applications
☻ Filtration
a) Principle
b) Methods
c) Applications
☻ conclusion
Objectives:

3. Food Processing is the process of converting the raw
materials into finished products by involving either
physical and chemical techniques.
The techniques include:
 Mixing
 Emulsification
 Extraction
 Filtration
 Centrifugation, etc.
Lets see about extraction and filtration techniques.
Introduction

4.  Extraction is the method of removing active constituents
from a solid or liquid by means of liquid sovent.
 Extract:
Extracts can be defined as preparations of crude drugs
which contain all the constituents which are soluble in the
solvent.
Types of Extract:
• Dry extract: Eg. Belladonna extract
• Soft extract: Eg. Glycerrhiza extract
• Liquid: As tincture.
Marc: Solid residue obtain after extraction.
Menstrum: Solvent used for extraction.
Extraction

5. .
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6. 1. Infusion
2. Decoction
3. Digestion
4. Maceration
5. Percolation
6. Supercritical Fluid
Extraction
7. Microwave Assisted
Extraction
8. Ultrasonication Assisted
Extraction

7.  Fresh infusions are prepared by macerating the crude drug
for a short period of time with cold or boiling water.
 These are dilute solutions of readily soluble constituents of
crude drugs.
 Types of Infusion:
 Fresh Infusion: eg. Infusion of Orange
 Concentrated Infusion: eg. Infusion of Quassia.

8.  In this process, the crude drug is boiled in a specified
volume of water for a defined time; it is then cooled and
strained or filtered.
 Eg. Tea and coffee
Decoction

9.  This is a form of maceration in which gentle heat is used
during the process of extraction.
 It is used when moderately elevated temperature is not
objectionable.
 The solvent efficiency of the menstrum is thereby
increased.
 Eg. Extraction of Morphine.
Digestion

10.  The solid ingredients are placed in a stopper
container with the whole of the solvent and allowed
to stand for a period of atleast 3-7 days with
frequent agitation until soluble matter is dissolved.
 The mixture is then obtained by filtration.
Maceration

11.  The continuous downward displacement of the solvent
through the bed of crude drug material to get extract.
 A percolator (narrow cone-shaped vessel open at both ends)
is used.
 It require less time than maceration.
Percolation
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12.  There is critical temperature(Tc) and critical pressure(Pc)
for every substance is referred as Supercritical Fluid
Extraction.
 Eg. Tc for CO2: 304.1 K; Pc for CO2: 73.8 bar
Supercritical Fluid extraction(SCF)

13.  This is done by continuous
flow of SCF from solids in a
batch process.
 Extraction medium is stored
in a feed tank and liquid
SCF is pumped from a
reservoir; it is heated and
pressurized to reach the
supercritical conditions and
then extracted
Supercritical Fluid Extraction

14.  Microwaves (about 2.45 GHz) are used extract the fluid
mixtures are regarded as Microwave Assisted Extraction.
 They offer rapid delivery of energy to a total volume of
solvent and solid plant matrix with subsequent heating of
the solvent and solid matrix, efficiently and
homogenously.
Microwave Assisted Extraction

15.  The procedure involves the use of ultrasound waves ,
which have frequencies higher than 20 kHz, have great
effects on extraction yield and kinetics.
Ultrasonication Assisted Extraction
(UAE)

16. Percolation is used to extract the Belladonna and Cardamom
tincture.
SCF extraction is used for Petroleum recovery, oils,
fragrances, impurities from agricultural and food products.
Pollution control.
MAE used to extract nutrachemical products from plant
sources in a faster manner than conventional solid-liquid
extractions.
UAE is used to extract oils from almond, apricot and rice
bran.
UAE is also used to extract carvone and limonene with
hexane.
General Applications

17.  Filtration is the technique of separating the products like
solids from fluids by imposing a porous medium through
which only the fluid can pass by mechanical or physical
operations.
 The fluid that passes through is called a filtrate.
filtration

18.  Since the filter medium is permeable only to the fluid, it
retains the solid particles and permits only the fluid to
pass through which is collected as the filtrate.
 The volume of filtrate collected per unit time(dV/dt) is
termed as the rate of filtration.
Principle of filtration

19. 1) Bed filtration
2) Plate and Frame Filtration
3) Continuous Rotary Filtration
4) Microfiltration
Methods of Filtration

20.  This is used to remove relatively small amount of solids
from large amounts of water in clarifying the liquid.
Bed Filtration

21.  Here, the feed slurry is pumped which flows through the
duct.
 The filtrate flows through the filter cloth and solids build up
as a cake on frame side of the cloth. The filtrate flows
between the filter cloth and the face of the plate through the
channels to the outlet.
Plate and Frame Filtration

22.  The solids are removed from liquids through different
sections of filtration zone around the central duct.
Continuous Rotary Filtration

23.  This is the method to separate the insoluble product,The
particle size of microfiltration is 0.1 to 10 micro metre.
 They separates macromolecules generally less than
100,000 g/mol.
 Eg. Na+ ions, small colloids and viruses, DNA, globular
proteins.
Microfiltration

24.  They further separates any contaminants that pass through
microfiltration membrane using a pressure gradient.
 They separates particle size about 0.1-o.oo1 micrometer.
 Mol.wt. of particle: 200-300,000 g/mol
Ultrafiltration

25.  Filtration is used to separate coffee from grounds in homes.
 They used in laboratories as HEPA filters to provide sterile
air
 They help in controlling environmental pollution.
 In kidneys, there occurs filtration of blood in glomerulus.
 On a industrial scale, it is used by oil, gas, food &beverages
and pharmaceutical industries.
 Municipalities use this to treat sewage and purify water.
 Furnaces use filtration to prevent the furnace elements
from fouling with particulates.
Applications

26.  Thus , we gained a clear knowledge on the extraction and
filtration procedures and its applications.
 They are essential in the physical conversion of foods
products in food processing industries.
Conclusion

27.  Desrosier,N.W-The technology of the Food
preservation CBS publishers, New Delhi.
 www.slideshare.net
 www.geafiltration.com
 www.aaflow.de/filtertech/index.html
Reference