Osmotic dehydration is a process that removes water from a food product through a semipermeable membrane into a concentrated solution. It uses a concentrated gradient to drive water removal from the lower concentration product to the higher concentration solution. This partial water removal reduces the load on dryers and enhances the storage life and quality of products by preventing enzymatic and oxidative browning through a mild treatment. Factors like the type and maturity of the product, concentration and temperature of the solution, and duration of the process affect osmotic dehydration.

1. OSMOTIC DEHYDRATION
• PRESENTATION BY
• UTKARSHJAIN

2. DEFINITION
 REMOVAL OF WATER FROM LOWER CONCN.TO SOLUTE OF HIGHER CONCN.
THROUGH SEMIPERMEABLE MEMBRANE.
 DRIVING FORCE FOR WATER REMOVAL : CONCENRATED GRADIENT.
 CONCENTRATED MEDIUM IS B/W SOLUTION & INTRACELLULAR FLUID.

4. ADVANTAGES
 SIMPLE EQUIPMENT IS REQUIRED FOR THIS PROCESS.
 REDUCES LOAD FROM DRYER BY PARTIAL WATER REMOVAL.
 STORAGE LIFE OF PRODUCT IS GREATLY ENHANCED.
 ENZYMTIC AND OXIDATIVE BROWNING IS PREVENTED.
 FAVOURS LESS HEAT DAMAGE TO COLOUR & FLAVOUR BY MILD TREATMENT.

5. DISADVANTAGES
 ACIDITY LEVEL REDUCTION REDUCES CHARACTERSTIC TASTE OF SOME PRODUCTS.
 SUGAR COATING IS NOT DESIREABLE IN CERTAIN PRODUCTS & QUICK RINSING MAY BE
NECESSARY AFTER TREATMENT.

6. OSMOTIC DEHYDRATION PROCESS

7. FACTORS AFFECTING OSMOTIC DEHYDRATION
1.SPECIES VARIETY AND MATURITY LEVEL
2.TISSUE LOCATION.
3. SIZE AND SHAPE .
4.CONCENTRATION OF OSMOTIC SOLUTION.
5.PROCESS TEMPERATURE.
6.SAMPLE TO SOLUTION RATIO.
7.PROCESS DURATION AND PRESSURE.