objectives of vacuum frying, comparison between atmospheric and vacuum frying, factors affecting vacuum frying, pretreatments before vacuum frying processing, vacuum fryer suppliers, what product can be vacuum fried, case study and summary

1. S H I K H A N G I S I N G H
M .T E C H ( P R O C E S S & F O O D E N G G . )
5 2 7 9 0
Vacuum Frying Technology: New
Technique for Healthy Fried Foods

2. OBJECTIVE
 Adopted as a food
preservation technique
 Method of new product
development
 Proper commercialization in
small as well as large industrial
scales.

3. • F r y i n g p r o c e s s b e l o w a t m o s p h e r i c p r e s s u r e
• D o n e b e l o w t h e b o i l i n g p o i n t o f w a t e r a n d h e n c e
t h e r e i s n o b u r n i n g o f t e x t u r e
• T h e f a t a b s o r p t i o n o f t h e p r o d u c t s i s a l s o l o w e r a s
c o m p a r e d t o a t m o s p h e r i c f r y e r
• W i t h v a c u u m f r y i n g i t i s e a s i e r t o m a i n t a i n n a t u r a l
c o l o r s a n d f l a v o r s o f t h e f i n i s h e d p r o d u c t s
INTRODUCTION

4. HEALTH PROBLEMS ASSOCIATED WITH
FRIED FOODS
•Increasedobesityrisk
•Increasedstrokerisk
•Increasedhypertensionrisk
•Increaseddiabetesrisk
•Increasedcancerrisk

5. • Frying happens below the boiling
point of water i.e. 100⁰C, so there is no
burning of any ingredients.
• No oxygen so no oxidation of
minerals.
• Nutrients and vitamin remains up to
100%.
• The absorption of oil reduced by 50%.
• Less prone to absorb moisture and
even degrade at 50% slower speed
than the normal fried in open.
• There is authenticity of the taste.
• Shape, color and texture of the
products remains close to original in
vacuum frying.
• Frying happens at 200-250⁰C. at this
temperature burning of ingredients
happens.
• Oxygen in atmosphere reacts with
minerals form oxide like calcium oxide,
iron oxide ,manganese oxide etc.
• Nutrients and vitamins get destroyed by
more than 50%.
• Absorbs higher amount of oil.
• Absorb moisture fast and degrade in 2-3
days if opened.
• There is not originality in taste.
• Shape, color and texture of the product
changes, deformation and degradation
take place.
Vacuum Frying Atmospheric Frying

6. VACUUM FRYING SYSTEM

7. VACUUM FRYING PROCESS
Fresh fruits
Peeling and slicing
Pre- treatments
Vacuum frying
Post
treatment(centrifugation)
Vacuum fried fruits

8. Pre- treatment
Blanching
Pre- drying
Osmotic
dehydration
Freezing
Anti-
browning
Agent
Hydrocolloids

9. Important Process Parameters
Time
Type of frying oil
Pressure
Temperature

10. Important Product Parameter
• Size and shape
• Ripeness of fruits
• Surface roughness
• Solid content
• Moisture content

11. ADVANTAGES OF VACUUM FRYER
Preserve natural color
Reduce shrinkage
Low water activity
Preserves heat sensitive nutrients
Prevention of carcinogen compounds
formation.
Reduce the fat content
Suitable for high contents products
Less adverse effect on oil quality

12. LIMITATIONS
Skilled person
Required special packaging
Pre- frying steps
Takes longer time
High vacuum fried foods cost
High investment cost for small
scale industry

13. Vacuumfryermanufacturersin
India

14. o Sukumar Debnath, principal scientist,
Department of Technology Scale-up, CSIR-
Central Food Technological Research Institute,
Mysuru, developed and installed a vacuum
frying system of 10 kilogram capacity to
manufacture healthy chips and savory snacks.
o Pune-based Ajit Soman set up Future Tech
Foods India about five years ago, imported
machinery from Singapore, and started
retailing under the Chopinz brand (that is
available on amazon.in).
…continue

15. Vacuum Fried garlic
chips
Vacuum fried
mango chips
Vacuum fried
mixed chips
Vacuum fried apple
chips
Vacuum fried
pumpkin chips
Vacuum fried
okra chips
Vacuum fried
jackfruit chips
Vacuum Fried Fruits and Vegetables

16. CASE STUDY

17. PROCESS
• Mangoes
• Green beans
• Sweet potatoes
• Blue potatoes
Raw material
• Peeled
• Sliced (1.5 mm thickness)
Sample preparation
• Maltodextrin(50%)-citric
acid (0.15%) solution
• Only green beans and
mangoes are soakedOsmotic dehydration
• Fresh canola oil of volume
7.5L was used
Vacuum frying and
atmospheric frying

18. Set up of the Vacuum Frying System

19. Treatments Used For Vacuum And Traditional Fr ying Experiments
Produce Oil
temperature(⁰C)
Frying time
(Sec)
Pressure (kPa) Moisture content(g/100)
Initial Final
Vacuum
frying
Blue potato 121±1 420 <1.33 77.22 ± 0.29 0.28 ± 0.08
Green beans 121±1 330 <1.33 79.84 ± 0.12 3.42 ± 0.43
Mango 121±1 180 <1.33 77.67 ± 0.43 1.48 ± 0.08
Sweet potato 130±1 120 <1.33 82.37 ± 0.08 3.00 ± 0.22
Traditional
frying
Blue potato 165±1 180 101.3 77.22 ± 0.29 0.81 ± 0.02
Green beans 165±1 300 101.3 79.84 ± 0.40 8.31 ± 0.03
Mango 165±1 240 101.3 77.67 ± 0.43 1.05 ± 0.02
Sweet potato 165±1 240 101.3 82.37 ± 0.08 5.13 ± 0.06

20. Color differences
Vacuum Fried Blue Potatoes
Vacuum Fried Green Beans
Traditional Fried Blue Potatoes
Traditional Fried Green Beans

21. Vacuum Fried Sweet Potatoes
Vacuum Fried Mangoes
Traditional Fried Sweet Potatoes
Traditional Fried Mangoes

22. Oil content of product fried in vacuum and
traditional fryers (white-bar: traditional
fryer; and black-bar: vacuum fryer).
Texture differences among samples fried in
vacuum and traditional fryers (white-bar:
traditional fryer; and black-bar: vacuum
fryer).

23. Color differences among samples fried in vacuum and traditional fryers (white-bar:
traditional fryer; and black-bar: vacuum fryer).
L*: Lightness
a*: Green-red chromaticity
b*: Blue-yellow chromaticity

24. Sensory scores of samples fried in vacuum and
traditional-frying conditions (white-bar: traditional fryer;
and black-bar: vacuum fryer 1: color; 2: odor; 3: texture;
4: flavor; and 5: overall quality).
Total retention of carotenoids and anthocyanin
among samples fried in vacuum and traditional
fryers (white-bar: traditional fryer; and black-
bar: vacuum fryer).

25. FUTURE SCOPE
Cost of machineries for small scale industries to be affordable
More studies needed to be done about application of vacuum frying
on traditional food products
Changes of sensorial impact during vacuum frying needs to be
established in comparison with conventional frying
Improvement of fundamental process modelling of vacuum frying
including the steps and changes taking place during the process

26. Summary
 The vacuum frying conditions (temperature and
time) for various food products varied
considerably and there was also a wide variation
in the vacuum pressures used
 The choice of the vacuum frying conditions for
the food samples was dictated by a range of
physical parameters, as well as pre-treatment
conditions
 There was no other way to design a vacuum
frying process for a specific product except to
carry out experiments to obtain an optimized
process

28. Thank you