Hurdle technology is a food preservation method that combines multiple techniques to inhibit microbial growth and enhance food safety and shelf life. This approach disrupts microbial homeostasis, leading to metabolic exhaustion and auto sterilization, while also engaging different preservation factors like temperature and acidity to target various microbial vulnerabilities. Practical applications demonstrate its effectiveness across different food products, although challenges include ensuring optimal hurdle combinations and addressing potential impacts on sensory quality.

1. HURDLE
TECHNOLOGY
SUBMITTED BY: NIYAZ ALI
SUBMITTED TO: MS. G. NAVYA

2. DEFINITIO
N
Hurdle technology is an
approach in food
preservation where
multiple preservation
methods are combined
to inhibit microbial
growth. Each method (or
'hurdle') weakens the
microorganisms,
creating a cumulative
effect that enhances
food safety and extends
shelf life.

3. ers to
stable
asis can
lead to
hurdles
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es
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2
3
4
PRINCIPLES
OF HURDLE TECHNOLOGY

4. Microbial
homeostasis refers to
the maintenance of stable
internal conditions.
Disrupting homeostasis can
prevent growth and lead to
cell death.
The use of multiple hurdles
disrupts homeostasis,
placing microorganisms in a
lag phase or leading to
death before repair is
possible. 1
ce
es
a
e
2
3
4
P
R
I
N
C
I
P
L
E
S

5. Microbial
homeostasis refers to
the maintenance of stable
internal conditions.
Disrupting homeostasis can
prevent growth and lead to
cell death.
The use of multiple hurdles
disrupts homeostasis,
placing microorganisms in a
lag phase or leading to
death before repair is
possible. 1
When microorganisms face
multiple hurdles, they
undergo metabolic
exhaustion.
This occurs when microbes
deplete their energy
reserves in an attempt to
maintain homeostasis in a
hostile environment.
This leads to auto
sterilization, where stable
foods become safer over
time as microbial activity
declines.
2
3
4
P
R
I
N
C
I
P
L
E
S

6. Microbial
homeostasis refers to
the maintenance of stable
internal conditions.
Disrupting homeostasis can
prevent growth and lead to
cell death.
The use of multiple hurdles
disrupts homeostasis,
placing microorganisms in a
lag phase or leading to
death before repair is
possible. 1
When microorganisms face
multiple hurdles, they
undergo metabolic
exhaustion.
This occurs when microbes
deplete their energy
reserves in an attempt to
maintain homeostasis in a
hostile environment.
This leads to auto
sterilization, where stable
foods become safer over
time as microbial activity
declines.
2
Some bacteria become more
resistant and virulent under
stress due to the generation of
stress shock proteins. These
proteins are produced in
response to stressful
conditions like heat, pH, water
activity (aw), ethanol, oxidative
compounds, cold, UV light, and
starvation, inducing a stress
reaction.
Simultaneous exposure to
multiple stressors forces
microorganisms to produce
more protective proteins,
which can lead to metabolic
3
4
P
R
I
N
C
I
P
L
E
S

7. Microbial
homeostasis refers to
the maintenance of stable
internal conditions.
Disrupting homeostasis can
prevent growth and lead to
cell death.
The use of multiple hurdles
disrupts homeostasis,
placing microorganisms in a
lag phase or leading to
death before repair is
possible. 1
When microorganisms face
multiple hurdles, they
undergo metabolic
exhaustion.
This occurs when microbes
deplete their energy
reserves in an attempt to
maintain homeostasis in a
hostile environment.
This leads to auto
sterilization, where stable
foods become safer over
time as microbial activity
declines.
2
Some bacteria become more
resistant and virulent under
stress due to the generation of
stress shock proteins. These
proteins are produced in
response to stressful
conditions like heat, pH, water
activity (aw), ethanol, oxidative
compounds, cold, UV light, and
starvation, inducing a stress
reaction.
Simultaneous exposure to
multiple stressors forces
microorganisms to produce
more protective proteins,
which can lead to metabolic
3
A recent advancement
in food preservation is
the multitarget
approach, which
aims to apply multiple
hurdles that attack
different microbial
targets (e.g., cell
membrane, DNA)
simultaneously. This
method offers a more
effective way to
preserve food by
creating a synergistic
effect between different
preservation factors.
4
P
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N
C
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P
L
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S

8. TYPES OF HURDLES

9. PHYSICAL HURDLES
1.Heat-based treatments:
pasteurization, sterilization,
evaporation, extrusion, baking,
frying
2.Low-temperature treatments:
chilling, freezing
3.Electromagnetic energy
treatments: microwave, radio
frequency, pulsed magnetic fields,
high electric fields
4.Pressure-based treatments:
ultra-high pressures,
ultrasonication
5.Atmosphere and packaging:

10. PHYSICO-CHEMICAL
HURDLES
Carbon dioxide, ethanol,
low pH, low redox
potential, low water
activity, organic acids,
ozone, salt, smoking,
sodium nitrite/nitrate,
sodium or potassium
sulphite, spices and
herbs, surface
treatment agents.

11. Microbially derived hurdles
Microbially derived hurdles
include bacteriocins,
competitive flora, and protective
cultures. Bacteriocins like nisin
inhibit harmful microbes, while
competitive flora and protective
cultures outcompete pathogens
through nutrient competition
and acid production.

12. EXAMPLES OF
HURLDES
SYMBOLS
1. F = Heating
2. t = Refrigeration
3. aw = Water activity
4. pH = Acidification
5. Eh = Redox potential
6. pres. = Preservatives
7. K-F = Competitive
organisms
8. V = Vitamins
9. N = Nutrients

13. ALL HURDLES AT THE SAME INTENSITY
In this scenario, each parameter is applied at an optimal, equal
level to prevent spoilage or pathogenic microorganisms. The
microorganisms must “jump” over each barrier.

14. HURDLES AT DIFFERENT INTENSITY
This indicates that some preservation techniques are used more
intensively than others, depending on the food product and the
microorganisms involved.
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15. LOW MICROBIAL LOAD
When only a small number of microorganisms are present at the
start, the risk of spoilage or foodborne illness is lower. The
microorganisms are already limited in number, so they need fewer
"hurdles" to be kept in check.

16. HIGH MICROBIAL LOAD
When there is a high microbial load at the start of food
production, more intensive or numerous hurdles are required to
ensure the safety and stability of the product.

17. THE BOOSTER OR TRAMPOLINE EFFECT
When a product is rich in nutrients and vitamins, it can act as an
excellent medium for the growth of microorganisms, leading to
what is referred to as the booster or trampoline effect. The
presence of abundant nutrients and vitamins can "boost" or
"accelerate" microbial growth, making the product more
susceptible to spoilage and microbial contamination.

18. PRACTICAL
APPLICATIONS

19. COCONUT WATER
The combination of natural
antimicrobials vanillin and
cinnamaldehyde with low-
temperature storage
significantly reduced the growth
of Salmonella Typhimurium in
coconut water. In a more severe
treatment, a 7-minute UV-C
exposure, combined with the
aforementioned antimicrobials
and storage at 5°C, completely
eliminated Salmonella growth
over 30 days.

20. LEAFY VEGETABLES
The combined use of calcium
oxide, fumaric acid, and
slightly acidic electrolyzed
water improved the
freshness and microbial
quality of fresh leafy
vegetables, enhancing their
shelf life and reducing
spoilage.

21. POTATOES
A synergistic effect was
observed when potatoes
were treated with slightly
acidic electrolyzed water and
exposed to ultrasound at
40°C for 3 minutes. This
treatment effectively
inhibited the growth of
Bacillus cereus under various
storage temperatures
ranging from 5 to 35°C.

22. MEAT
A combination of 1%
lemongrass oil and UV-C light
exposure (200 uW/cm² for 2
minutes) to reduce
Escherichia coli populations
in meat to below detectable
levels. The synergistic effects
of this combination were far
higher than using individual
treatments.

23. MILK
Mild heat treatment (50°C)
combined with pulsed
electric fields (30 kV at 50°C
for 6 minutes) significantly
reduced microbial load and
alkaline phosphatase activity
in milk. This hurdle
combination extended the
shelf life of milk by 22 days.

24. CHICKEN SAUSAGES
By lowering water activity
using textured soy protein
and reducing pH with lactic
acid, the shelf life of chicken
sausages could be extended
to six days. This method
reduced microbial activity
and improved product
stability without the use of
extreme preservation
techniques.

25. LIMITATIONS
Complexity in Implementation
•Difficult to determine the right combination and
intensity of hurdles.
•Extensive trial-and-error required for optimization.
Impact on Sensory Quality
•Can alter taste, texture, color, or aroma, affecting
consumer acceptability.
Regulatory and Safety Concerns
•Novel methods may face regulatory hurdles and
require extensive testing.
•Improper application can pose safety risks.
Need for Precise Knowledge and Expertise
•Effective hurdle technology requires "a precise
knowledge of the effectiveness of each hurdle for a given
commodity"

26. CONCLUSION
In conclusion, hurdle technology is a highly
effective and innovative approach in food
processing that combines multiple
preservation techniques to enhance food
safety, quality, and shelf-life while retaining
nutritional and sensory characteristics. By
applying a combination of mild preservation
methods—such as heat, pH control, water
activity reduction, and fermentation—hurdle
technology can achieve the same or superior
results compared to traditional methods, but
often with reduced reliance on extreme
conditions such as high temperatures or

27. REFERENCE
 Gómez, P. L., Welti-Chanes, J., & Alzamora, S. M. (2011). Hurdle Technology in Fruit Processing. Annual Review of Food Science and
Technology, 2(1), 447–465. https://doi.org/10.1146/annurev-food-022510-133619
 Khan, I., Tango, C. N., Miskeen, S., Lee, B. H., & Oh, D.-H. (2017). Hurdle technology: A novel approach for enhanced food quality and safety –
A review. Food Control, 73, 1426–1444. https://doi.org/10.1016/j.foodcont.2016.11.010
 Leistner, L. (1994). Further Developments in the Utilization of Hurdle Technology for Food Preservation. In Water in Foods (pp. 421–432).
Elsevier. https://doi.org/10.1016/B978-1-85861-037-5.50029-1
 Leistner, L. (1995). Principles and applications of hurdle technology. In G. W. Gould (Ed.), New Methods of Food Preservation (pp. 1–21).
Springer US. https://doi.org/10.1007/978-1-4615-2105-1_1
 Leistner, L. (2000). Basic aspects of food preservation by hurdle technology. International Journal of Food Microbiology, 55(1–3), 181–186.
https://doi.org/10.1016/S0168-1605(00)00161-6
 Leistner, L., & Gorris, L. G. M. (1995). Food preservation by hurdle technology. Trends in Food Science & Technology, 6(2), 41–46.
https://doi.org/10.1016/S0924-2244(00)88941-4
 Singh, S., & Shalini, R. (2016). Effect of Hurdle Technology in Food Preservation: A Review. Critical Reviews in Food Science and Nutrition, 56(4),
641–649. https://doi.org/10.1080/10408398.2012.761594