Blanching

COVERS ABOUT:
BLANCHING,FACTORS AFFECTING BLANCHING TIME,OBJECTIVES OF BLANCHING, METHODS OF BLANCHING, EQUIPMENT OF BLANCHING, STEAM BLANCHER, HOT WATER BLANCHER,ITS MAIN DESIGNS,REEL BLANCHER,PIPE BLANCHER,INDIVIDUAL QUICK BLANCHING,EFFECTS ON FOOD BY BLANCHING.

1. BLANCHING TOPICS TO BE COVERED FACTORS AFFECTING BLANCHING TIME OBJECTIVES OF BLANCHING METHODS OF BLANCHING EFFECT ON FOODS PRESENTATION BY UTKARSH JAIN

2. BLANCHING USED TO DESTROY ENZYMATIC ACTIVITY TEMPERATURE VARIES FROM 88-99 DEGREE CELCIUS.

3. FACTORS AFFECTING BLANCHING TIME TYPE OF FRUIT/VEGETABLE. SIZE OF PIECES OF FOOD BLANCHING TEMPERATURE METHOD OF HEATING

4. OBJECTIVES OF BLANCHING TO SOFTEN TISSUE TO FACILITATE PACKAGING TO AVOID DAMAGE TO PRODUCT TO ELEMINATE AIR FROM PRODUCT TO PRESERVE NATURAL COLOUR TO DESTROY UNDESIREABLE ENZYMES TO PRESERVE NATURAL FLAVOUR

5. METHODS OF BLANCHING TWO MOST COMMON METHODS STEAM BLANCHING HOT WATER BLANCHING BOTH METHODS ARE RELATIVE SIMPLE AND INEXPENSIVE.

6. STEAM BLANCHING FRUITS/VEGETABLES ARE STEAMED FOR 30-90 SECONDS. VOLUME OF WASTE WATER IS LESS HIGHER NUTRIENT RETENTION

7. HOT WATER BLANCHING FRUIT/VEGETABLE DIPPED IN HOT WATER. TIME:B/W 1-5 MINS

8. AFTER BLANCHING COOLING IS DONE BY COLD AIR OR COLD WATER. COOLING WITH RUNNING WATER. INCREASES LEACHING LOSS. GAINS WEIGHT BY ABSORBING WATER. COOLING BY AIR. NUTRIENT RETENTION. WEIGHT LOSS BY EVAPORATION.

9. EQUIPMENT FOR BLANCHING STEAM BLANCHER CONSISTS OF MESH CONVEYER. CARRIES FOOD THROUGH STEAM ATMOSPHERE. RESIDENCE TIME :DEPENDS ON SPPED OF CONVEYER.

10. EQUIPMENT FOR BLANCHING HOT WATER BLANCHER RETAINS FOOD IN HOT WATER TEMPERATURE:70-100 DEGREE CELCIUS. THEN IT REMOVES IT TO A DEWATERING COOLING SECTION

11. EQUIPMENT OF BLANCHING MAIN DESIGNS OF HOT WATER BLANCHING 1.REEL BLANCHER. FOOD ENTERS A SLOWLY ROTATING MESH DRUM. IT IS PARTIALLY SUBMERGED IN HOT WATER. HEATING TIME : DETERMINED BY SPEED OF ROTATION.

12. 2. PIPE BLANCHER. FOOD IS IN CONTACT WITH HOT WATER. WATER RECIRCULATES THROUGH A PIPE. RESIDENCE TIME : DETERMINED BY LENGTH OF PIPE. VELOCITY OF WATER.

13. IN CONVENTIONAL STEAM BLANCHING: THERE IS POOR UNIFORMITY OF HEATING. TO OVERCOME THIS INDIVIDUAL QUICK BLANCHING WAS INTRODUCED.

14. INDIVIDUAL QUICK BLANCHING INVOLVES 2 STAGES FIRST STAGE FOOD IS HEATED IN SINGLE LAYER TO SUFFICIENTLY HIGH TEMPERATURE SECOND STAGE DEEP BED OF FOOD IS HELD FOR SUFFICIENT TIME. THIS ALLOWS TEMPERATURE AT CENTRE OF EACH PIECE TO INCREASE TO NEEDED TEMPERATURE OF ENZYME INACTIVATION.

15. EFFECT ON FOODS NUTRITION SOME MINERALS,SOLUBLE VITAMINS AND OTHER COMPONENTS ARE LOST. LOSSES OF VITAMINS:MOSTLY BY LEACHING. NUTRITION LOSS DEPENDS ON MATURITYAND VARIETY METHOD OF BLANCHING TIME AND TEMPERATURE OF BLANCHING METHOD OF COOLING

16. EFFECT ON FOODS COLOUR BRIGHTENS THE COLOUR OF FOODS HOW?? BY REMOVING AIR &DUST FROM SURFACE