Achieving the perfect taste or texture is only the beginning – from then on, your customers expect perfect consistency, year after year. In this webinar, we explored the issues that can cause unexpected problems, how manufacturers can avoid getting blindsided, and surefire methods for delivering consistency.

2. SNACK FOODS
MANAGING MOISTURE
Mary Galloway
Application Scientist
METER Group, Inc. USA

3. CONTENTS
Top 3 Snack Food Pit-falls
• Rancidity
• Texture Changes
• Moisture Migration
Product Formulation
Achieving Consistency

4. SNACK FOODS

5. SNACK FOODS
Diverse group of products
Ready to eat
Low to intermediate moisture foods
Packaged to easily consume

6. SNACK FOODS
Strive for specific consumer experience
Many have long history and brand recognition
Not worried about mold issues
Is water activity useful?

7. WHAT HAPPENS WHEN
PROBLEMS ARISE?
Trail mix now has
rancid nuts?
Bars are getting
hard or worse,
molding before the
expiration date?
Filled cakes are
sticky in the
package?
Can future
problems be
foreseen and
avoided?
What about new
formulations?

8. TOTAL MOISTURE
Moisture content needed
for the right texture but
cannot help with moisture-
related issues
Total Moisture
measurement
relate MC to water activity,
which is crucial to solving
moisture-related problems

9. Lipid Oxidation -
Rancidity
Moisture Migration
Change in Texture

10. LIPID OXIDATION - RANCIDITY

11. LIPID OXIDATION
High fat contents
• Chips, nuts, fried items, cheese,
seeds
Low moisture contents and
water activities (aw)

12. LIPID OXIDATION
EFFECT OF AW

13. LIPID OXIDATION
• Products are generally in the 0.1-0.2 aw range to maintain
their crispness
High rate of oxidation >0.2; Lowest 0.3-0.5
• Can reduce O2 with oxygen absorber or with a N2 flush
• Pick the right packaging (WVTR & OTR)
• Minimize the effect of light
Need to balance texture and rancidity

14. CHANGE IN TEXTURE

15. CHANGE IN TEXTURE
Foods susceptible to texture
change:
• Crisps, dried fruit, cookies, crackers,
bars, confections, functional
ingredients
Low to mid-range moisture contents
and water activities (aw)

16. CHANGE IN TEXTURE
What can cause a loss in texture?
Ambient conditions affecting product
• Impact of packaging
• Moisture can be gained or lost
• Storage conditions, temp. & %RH
• Increase temperature = increase aw
Packaging

17. CHANGE IN TEXTURE
0
10
20
30
40
50
60
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
MoistureContent(%w.b.)
Water Activity
KALE CHIPS
RHc = 0.57
If we can keep aw of chips below 0.57, they maintain the
crisp texture and are not susceptible to molding.

18. MOISTURE MIGRATION

19. MOISTURE MIGRATION
Moisture migration between 2
or more components:
• Filled cookies and cakes, bars with
inclusions (fruit, nuts, chocolate),
fruit and nut mixes, coated cakes
and cookies

20. MOISTURE MIGRATION
0.66 aw 0.43 aw
Why does moisture move?

21. MOISTURE MIGRATION
How to manage moisture
migration?

22. MOISTURE MIGRATION
Predict the final aw after
mixing and determine how
that affects all components
Cold pressed bar example:
 Date paste
 Cashews
 Coconut
0.63 aw

23. MOISTURE MIGRATION
Pick a common aw
(adjust each component’s aw)
• Each component has a unique texture
• 3 components have very different moisture
contents

24. MOISTURE MIGRATION
Pick a common aw
(adjust each component’s aw)
• Each component has a unique texture
• 3 components have very different moisture
contents
• All 3 components have same water activity
• Maintaining the unique texture and quality of
each component is made possible by formulating
to the same water activity

25. MOISTURE MIGRATION
Other ways to manage moisture migration
 Slow diffusion process (fats, starches)
 Moisture barrier (chocolate)
 Separate packaging

26. NEW FORMULATION

27. NEW FORMULATION
Be aware of moisture pitfalls and avoid:
Lipid
Oxidation
Chips, nuts, fried
items, cheese, and
seeds
Change
in Texture
Crisps, dried fruit,
cookies, crackers,
bars, confections,
functional
ingredients
Moisture
Migration
Filled cookies and
cakes, bars with
inclusions, fruit and
nut mixes, coated
cakes and cookies

28. NEW FORMULATION
 Know how ingredient changes
affect the final product
 Characterize new formulations
Relate degradation of
functional ingredients to aw
 All key information (moisture
content, aw, shelf life, potency)
correlated to find the optimum
product formulation
MoistureContent
(%w.b.)
Water Activity
Formulating a new variety or
clean label reformulation
(no preservatives,
reduced sugar)

29. PRODUCING CONSISTENCY

30. PRODUCING CONSISTENCY
Consumers are more
inclined to try a new product
if they like the brand
Brand loyalty developed
from producing consistency
Negative experiences
impact future perceptions

31. aw
MC
Lost
yield
and
revenue
Lost quality Lost safety
Sweet spot for
optimizing quality,
safety, yield and
revenue
PRODUCING CONSISTENCY

32. PRODUCING CONSISTENCY
Use Total Moisture measurements (%MC, aw) in-process
to:
 Set process specifications
 Track changes during production
 Make process adjustments before it’s too late
 Deliver a reliable product
 Maintain the desired shelf life with no surprises

33. Balance texture and
oxidation
Manage the moisture
within a product
Formulate with key
data
Use Total Moisture
readings to consistently
produce over every
batch
KEY POINTS

34. QUESTIONS?