Application of evaporators in fruit and vegetables processing

1. Application of Evaporators in
Fruit and Vegetable
Processing
Submitted to: Submitted By: Preeti Birwal
Dr. Rekha Menon PhD (DE)
NDRI

2. Introduction
 The process of evaporation is widely used to concentrate foods
 Evaporation technology is a process of separating substances by
means of thermal energy. The concentrated liquid, which is still
pump able, usually is the desired final product.
 Three element: Heat transfer, Vapor-liquid separation and vapor
condensation

3. Objectives
 To reduce water activity and lengthen shelf life
 To reduce packaging, transportation, and storage cost (Reduction in
bulkiness)
 To improve the stability and handling of the product.
 It may be used as an economical preparatory step for subsequent
dehydration, as in the cases of spray drying, drum drying, vacuum
drying, freeze-dried, crystallization and mixing (Food mixing).
 Pre-concentration reduces cost of energy for subsequent processes.
 Concentrate as commodity is easier to market.

4. Applications
Evaporators are used in a wide range of processes,
including pharmaceuticals, foods, beverages, juices
dairy industry, sugar syrups, pulp and paper,
chemicals, polymers and resins, inorganic salts,
acids, bases, and a variety of other materials.

5. Fruits and Vegetables
 Fruit puree( Grapes, apple,
cherry)
 Grape juice
 Lime juice
 Pear juice
 Pineapple juice
 Mango juice
 Orange juice
 Citrus juices
 Blueberry juice
 Beetroot juice
 Carrot juice
 Passion fruit juice
 Acerola juice
 Coconut juice
 Other vegetable juices

7. Selection of Evaporators
 Evaporators chosen all on fruit properties: chemical, rheological and
thermal.
 The necessary high final concentrations, depend on the type of fruit,
degree of ripeness, juice production method, pretreatment and the
fiber and pulp proportion.
 For most fruit juices, 316 stainless steel is used

8. Types of Evaporators
 Unstirred Open Pan or Kettle
 Multi-effect Evaporator: Falling and Rising
 Short Tube Vertical Evaporator
 Agitated Thin Film Evaporator (ATFE)
 Thermally Accelerated Short Time Evaporators (TASTE)
 Plate evaporators: Falling Film, Rising/Falling Film, Paravap, Paraflash
 Centritherm
 Falling Film Long Evaporator (FFLE)
 Scraped Surface Evaporator (SSE)

9.  Unstirred Open Pan or Kettle: operating at atmospheric pressure, steam
jacketed or heated with closed steam coils and are used for concentration of
sauces, jams, and confections products, operating temperatures is 100.8°C
 Falling Film Evaporator: largely used for fruit juices.
 Plate Evaporators: can be used on a broad range of products, the main
application has been with products that are heat sensitive and therefore benefit
from the high HTC’s and low residence time.
 Rising/Falling Film Plate Evaporator: use in juice processing for product where
low residence time and less temperature below 90°C is required.
 Falling Film Plate: system with the added benefits of shorter residence time and larger
evaporation capabilities, has wide acceptance for heat sensitive products.

10.  Paravap: thin film turbulent evaporator, atomize system
provide grater surface area. Finishing evaporator to
concentrate materials to high solids. Used for apple puree
(70°Brix), Cherry puree (60°Brix) and grapes puree
(50°Brix)
 Paraflash: suppressed boiling, forced circulation, used for
product which subject too high fouling in falling film
evaporators. Ex. grape juice etc.
 Short Tube-Vertical Evaporator: concentration of sugar
cane juice.
 Scraped Surface Evaporator: for tomato puree (Highly
viscous)

13.  FFLE (Falling Film Long Evaporator): is the current development in the plate
evaporator technology. Has a 50% longer flow path. This creates thinner films off the plate,
with improved wetting characteristics. The FFLE is current state-of-the art technology,
producing concentrates of high quality on a wide range of juices
 Centritherm Evaporator: continues to be the evaporator of choice for heat sensitive,
viscous and high value products where color, functionality and flavor are important.
Pineapple juice concentrates from 12°Brix to 87°Brix, Carrot up to 65°Brix, Blueberries up
to 73.5°Brix , Grape juice to 70°Brix and coconut water to 65°Brix. It is used in citrus
energy at higher temperature.
 Agitated Thin Film Evaporator (ATFE): concentration of orange juice
 Thermally Accelerated Short Time Evaporators: high-temperature short-time, multi-
effect vacuum tubular evaporators, evaporates 65% solids desired for frozen orange juice

14. Centritherm
TASTE
ATFE

15. Reference
 APV, Evaporator hand book.
 GEA, Evaporation technology for the juice industry.
 Karel M. and Lund B. D. (2003), physical principle of food preservation, second
edition, chapter;9, concentration, 330-349.
 Kerkai H. E. and Mate S. M., manufacturing fruit beverages and concentration,
Handbook of fruit and fruit processing, Authors; Sinha N., Sidhu J., Barta O., Wo
J., Chapter;13, 215-228.
 Sandhu S. K. and Mindas D. K., Orange and citrus juice, Handbook of fruit and
fruit processing, Author; Y. H. Hui, Chapter; 19, 309-357.
 Skaliotis L., 2012, Beverage application using spinning cone technology. Food
marketing and technology, 26-28.
 William B. Glover (2004), Selecting evaporators for process applications,
Chemical Engineering Progress, 26-33.

16. Thank You