Transcript PPT

Ozone Technology For Fruits &
Vegetables and their +ve & -ve impacts
Sanya Hassan (10)
Ayesha Anwar (09)
Saba Tufail (11)
8th semester (Regular)
Institute of Food Science & Nutrition
University of Sargodha
Contents
•
•
•
•
•
•
•
•
•
Ozone and its History
How it formed ??
Why the Ozone ??
Pathogen dosage
Ozone Applications for Fruits and Vegetables
Extension of storage life with food
Positive and negative impacts of ozone
Conclusion
References
Ozone
Ozone
• Ozone (O3) is a powerful gas molecule
consists of three oxygen atoms formed by
dissociating two atoms that compose the
oxygen gas.
• Ozone has extremely great oxidative power
and very ready to react to germs, viruses, and
a host of microbes that are known to cause
illness.
Ozone
HISTORY OF OZONE IN THE FOOD INDUSTRY
1910
Ozone is used for the first time in the preservation of frozen meat in Germany.
1936
Ozone is used for showering (wash) and keeping the fish in France.
1942
Ozone is used in eggs and cheese stores in the United States.
1977
Ozone is used to reduce Salmonella on eggshells in Russia.
1982
Ozone is used for bottled water in the United States. This declaration was
reaffirmed in 1995.
1997
A panel of experts concluded that ozone could be declared GRAS for food
processing in the United States.
2001
2001
The FDA (Food and Drug Administration) recognizes ozone as a direct food
additive second class.
FSIS (Food Safety and Inspection Services) determined to be acceptable
ozone use in meat and poultry.
Ozone
How does OZONE Work?
Ozone is an unstable molecule that rapidly decays to O2, releasing a single
oxygen atom which is extremely reactive
This atom reacts with the cell membrane of the bacteria or virus, attacking the
cellular components and interrupting the normal cell activity, which rapidly
destroys those microorganisms.
If the ozone is brought into contact with the volatile substance, the free oxygen
atom reacts with them, removing characteristic odors of these compounds..
Effects ozone on bacteria
Bacteria cell oxidation via ozone contact
typically occurs within 1-10 seconds!
How ozone is formed ?
1. Lightening
An electrical discharge (a
spark) splits an oxygen
molecule into two oxygen
atoms. (Electrical
discharge is also referred
to as corona discharge.)
These unstable oxygen
atoms combine with other
oxygen molecules. This
combination forms ozone.
2. UV light (Sun)
• Oxygen in the presence of 185 nm UV light creates
ozone. (Naturally)
• Oxygen turns into ozone after it is hit with 185 nm
UV light from a UV bulb. (Artificially)
Advantages of UV Light
• Simple construction
• Lower cost than corona discharge
• Output less affected by humidity
Ozone
Why the ozone?
•
•
•
•
Most powerful oxidizer available
Instantly destroys microbes
Environmentally friendly
Stops mold spores
Conti..
•
•
•
•
Food remain fresh
Extend shelf life of fruits and vegetables
Strong antimicrobial agent
Higher oxidation-reduction potential (2.07 V)
than that of chlorine (1.36 V)
Conti…
•
•
•
•
•
•
Does not affect product taste
No harmful by-products
Can be used in air and water
Kills cancerous elements
Reduces acidity in body
Delays the ripening of fruit, with positive
effects
What is Ethylene ???
• Ethylene is colorless gas with a faint sweetish
smell that is the naturally produced ripening
hormone of some fruits.
• The important role of ethylene as a plant
growth regulator has only been established
over the last 50 years but its effects have been
known for centuries.
Ethylene stimulates
• Ethylene is active at very low concentration
• Ethylene act as growth regulator in plants and
fruits.
• Ripening of climacteric and non climacteric
fruits.
• Respiration
Effect of Ethylene on fruits and veg
• 2 classes in terms of ethylene production
1. Climacteric Fruits
Fruits can be harvested when mature but before
ripening has begun
These fruits produce a bursts of ethylene as they
ripe.
The internal ethylene concentration varies when
they get ripen.
E.g. Apple , Mango
2. Non-Climacteric Fruits
• Fruits which ripe only when still attached to
the parent plant.
• These fruits do not increase ethylene
production when they ripe.
• The internal ethylene concentration change
little during development and ripening.
• E.g. Strawberry, cucumber
Detrimental effects
•
•
•
•
•
•
Enhances extra softening of fruits
Stimulate chlorophyll loss
Stimulate sprouting (potato)
Promotes discoloration (browning)
Stimulate respiration
Premature death
• Ethylene production is not always beneficial.
• The major reason for the loss of shelf life is
that ethylene exposure increases the rate the
product ages.
• The degree of damage depends upon
– Concentration of ethylene
– Length of exposure time
– Product temperature
Methods of reducing Ethylene production
• Most common and effective method is
• Oxidation with Ozone
Ozone is much suitable since it is gaseous,
it readily mix with ethylene
• Other oxidants may used for oxidation of
ethylene production
• Like Activated charcoal, Tetra zine
Pathogen Dosage
Aspergillus Niger (Black Mount)
1.5 to 2 mg/I
Bacillus Bacteria
0.2 m/I within 30 sec
Salmonella Bacteria
Very susceptible
Salmonella typhimurium
0.25 mg/l for 1.67 minutes
Vibrio Cholera Bacteria
Very susceptible
Candida Bacteria
Ozone susceptible
Ozone Applications for Food
Products and Processing
– Ozone and Cold Storage
– Ozone food preservation
– Ozone Sterilizer
– Washing fruits and vegetables
Ozone and cold storage
• The shelf life of produce in cold storage can also be
extended by the use of gaseous ozone.
• Ozone in the air within a cold storage room can retard
the growth of microorganisms in the air and on the
surface of the produce.
• Ozone is also effective in breaking down ethylene gas
which is given off by some fruits and accelerates the
ripening process.
Ozone Food Preservation
• Ozone can reduce contamination on food and increase
storage life.
• The age-enhancing hormone ethylene is instantly
destroyed.
• This reduces spoiling and keeps the food looking
fresh.
Effects of ozone on red cherry
Effect of ozone on vegetables
Capsicum
Ozone is better or Chlorine ???
• Ozone is known to kill bacteria in water 500 times
faster than chlorine.
• Ozonation helps fruit and vegetables stay fresh up to
three times longer than chlorine.
• Oxidizing agent of ozone is 1.5 times stronger than
chlorine
• Chlorination produces harmful disinfectant byproducts. chloramines trihaomethanes and
chloroorganic residues on processed foods.
Ozone Sterilizer
• Machines that generates ozone are known as ozone
sterilizers machine.
• There are basically two type of machines are there viz.,
 Air-based
 Water-based ones.
•
However, they both work under the same concept as they
differ only in the method of ozone delivery.
Water-based Ozone Sterilizer
• For this particular type of ozone sterilizer, ozone
gas are pumped into a basin where the target
items such as meat, vegetable and fruits are
submerged in water.
• The activity of ozone occurs in the water itself
leaving coagulation of impurities like pesticides,
herbicides, and bacteria clump floating on the
surface and further being discarded.
• This is the most preferred type of machine as it
is multifunctional (also capable of sterilizing
water), clean and simple to be used.
Air-based Ozone Sterilizer
• Unlike the water-based type, the delivery
method used in air-based ozone sterilizer is
rather simple.
• Food items are placed directly into the enclosed
chamber of the machine and ozone gas
generated are shot directly onto the surface of
the target allowing the disinfection activity to
occur in the air.
• This machine uses less power compared to a
water-based machine.
Ozone Food Washer
How it works ?
• The product that are to be ozonized as whole are sprayed
with potable water to remove the adhering dirt.
• Put the product in the food washer.
• The lid of the container is closed and the tube that carries
ozone from the generator is inserted into the container
• The ozone generator is turned on and the ozone gas is
bubbled in through the wash water and thus the process of
washing starts.
• The treated samples are derived from the treatment
container at a time interval of 5 minutes, for up to
20 minutes.
Common Applications for Ozone use in Food
Storage
• Potato Storage Facilities
• Onion Storage Facilities
• Citrus Fruit Storage
• Vegetable Storage
• General Cold Storage Facilities
Extension of
storage life with
ozone
Storage
Conditions
Food
Extension
Bananas
substantial
A few ppm O3 @ 12°C,
if fruit is not within a
few days of its period
of rapid ripening.
Strawberries,
Raspberries, Currents,
Grapes
100%
2-3 ppm O3,
continuously or several
hours each day.
Apples
several
1.95 cm3 O3/m3
Potatoes
6 months
3 mg/L O3; 6-14°C; 9397% RH
The Effect of Ozone Treatment On Fresh And
Fresh-cut Fruit And Vegetables
• Treatment with ozone seems to have a beneficial
effect in extending the storage life of fresh non-cut
commodities such as
• Apples
• Grapes
• Tomatoes
• Cherries
• Oranges
• Strawberries
• Fresh cut salad
Apple:
• Treatments on apples with ozone resulted in a
reduction of weight loss
• Spoilage.
Onions:
• Treated onions during storage resulted in
decrease mold.
• Bacterial counts
Tomatoes:
• Treatments on tomatoes with ozone reduced
bacterial
• fungal population
Fresh-cut salad:
• Treatment on fresh cut
salad with ozone water
extend the shelf life.
Ozone reduces Fungal Spoilage of Fruits
and Vegetables
• Treating fresh produce with ozone increases its
resistance to fungal infection.
• Tomatoes exposed to ozone became more fungusresistant, even once they were removed from the
ozone gas.
• This experiment performed by Dr. Singleton and
plant biologist Prof. Jerry Barnes.
Health benefits of ozonated water
• kill viruses, bacteria, fungi and algae on
contact
• It has cancer killing properties
• It can boost the immune system
• It has a neutralizing effect on harmful toxins
• It can assist with the removal of chemical
toxins and residue left over in the body from
medications.
• Effective for skin disorders.
• If you suffer from skin disorders bathing in ozonated
water is a great therapy. Bathing in or even drinking
the ozonated water can work wonders on sore muscles,
spinal or back injuries and neck stiffness. It is gentle
and effective cleanser for the skin, it is especially
helpful in treating acne, blackheads and pimples.
• It can convert wastes and toxins into water and
carbon dioxide and afterwards they can easily
be expelled from the body.
• The ozonated water will help eliminate toxins
and is recommended before treatments such as;
massage therapy, acupressure, acupuncture and
spinal touch.
• This reduces heart complications that is
created in the mouth. With increased levels of
oxygen in the blood overall cardiovascular
function and health is improved.
• ozone cleanses the liver.
• Fungal infections, like athlete’s foot,
ringworms and nail fungus can be treated
using water that has been ozonated for 10
minutes.
• Use it to clean dishes in order to kill bacteria
and other pathogens.
• Using ozonated water to brush teeth can help
eliminate bad breath and cure gum problems.
Disadvantages of ozonation
• Relatively high equipment costs
• Requires large amounts of energy
• Qualified professionals required for design and
system maintenance
• Formation of potentially harmful disinfection
by-products (DBPs) in the case of brome
existence in water
• Potential fire hazard and toxicity associated
with ozone generation
• Ozone is less soluble in water, compared to
chlorine, and, therefore, special mixing
techniques are needed.
• The process of creating ozone in the home
requires electricity. Loss of power means
no purification.
Conclusion
• The results from this study support the following conclusions:
• Almost all patients suffer from hypoxia which is lack of
oxygen in the cells.
• Fatigue, depression, irritability and poor judgment are all signs
of ever increasing lack of oxygen.
• A few hundred years ago, the oxygen content in the air was
38% which has now reduced to some 17-19%.
• Not possible for a common man to grow all his fruits and
vegetables organically.
References
• Dickson, R. G., Law, S. E., Kays, S. J., Eiteman, M.A. 1992. Abatement of
ethylene by ozone treatment in controlled atmosphere storage of fruits and
vegetables. Proc. 1992 International Winter Meeting, Am. Soc. Agric. Eng.
1-9.
• Rice, R. G., and Netzer, A. 1984. Handbook of ozone technology and
applications. Vol. 2. Ozone for drinking water treatment. Butterworth,
Stoneham, MA.
• McKenzie, K. S., Kubena, L. F., Denvir, A. J., Rogers, T. D., Hitchens, G. D.,
Bailey, R. H., Harvey, R. B., Buckley, S. A., and Phillips, T. D., 1998,
Aflatoxicosis in turkey poults 792 A. D. Proctor et al. is prevented by
treatment of naturally contaminated corn with ozone generated by
electrolysis. Poultry Science, 77, 1094–1102.
References
• Graham, D.M., Pariza, M., Glaze, W. H.,Newell, G. W., Erdman, J. W.,
Borzelleca, J. F. 1997.Use of ozone for food preservation. Food Technol.
51(6):72-76.
• Spalding, D. H. 1968. Effects of ozone atmospheres on spoilage of fruits
and vegetables after harvest. Agricultural Research Service USDA
Marketing Research Report No. 801.
• Nickols, D. and Varas, A. J. 1992. Ozonation. In: Disinfection Alternatives
for Safe Drinking Water. Bryant, E.A., Fulton, G. P., and Budd, G. C. Van
Nostrand Reinhold, New York. pp. 197-258.