The document discusses intermediate moisture foods (IMF), which have water activity levels between 0.6-0.9, enabling safe storage and palatability without refrigeration. It highlights the role of water activity in preventing microbial growth, particularly emphasizing the need for preservatives and the effectiveness of sugar in preserving fruits. While IMFs offer advantages like cost-effectiveness and stability, issues such as high additive levels and texture degradation pose challenges that necessitate careful handling and quality improvement efforts.

1. SUBMITTED TO :DR. SOMESH SHARMA
Submitted By: Manorma Negi
Deptt. Of B.tech Foodtechnology
12ftb(s)034 ,4th semester

3. INTERMEDIATE MOISTURE FOODS:
A food product that has a water
activity below that which is required
for the growth of microorganisms; or
a food containing unavailable
water.IMF foods have water activity
in B/w 0.6-0.9 or 10 to 50% moisture.

4. WHAT IS WATER ACTIVITY?
 Water activity is a thermodynamic property which is
defined as the ratio of vapor pressure of water in a
food system and vapor pressure of pure water at
the same temperature.

6. EFFECT OF AW ON PROPERTIES OF
FOOD:

8. PURPOSE OF INTERMEDIATE MOISTURE
FOOD:
 The purpose is to achieve a desirable water activity by the
various ingredients so that food product maintain enough
water for palatability and can be stored safely.
 Addition of preservatives provides the margin of safety against
spoilage organisms
 Staphylococcus aureus is one of the organism of high concern
which can tolerate aw as low as 0.83-0.86 under aerobic
conditions.

9. FRUITS PRESERVED UNDER IMF CONCEPT:
 The application of IMF technology has been very
much successful in preserving fruits and vegetables
without refrigeration.
 The addition of high amount of suger in fruits during
processing will create a protective layer against
microbial contamination after the heat processing.
 The sugar acts as aw depresser limiting bacterial
growth.
 These foods are more stable at room temperature.

10. EXAMPLES OF IMF:
 Jams
 Jellies
 Candies
 Baked foods
 Honey
 Dried fruits and vegetables

12. ADVANTAGES:
 Low aw thus aw is the primary hurdle to achieve the
microbial stability and safety.
 Easy to prepare and store without refrigeration.
 These are energy efficient and relatively cheap.
 They don’t get easily spoiled even if the package is
damaged(bcs of low aw).

13. DISADVANTAGES:
 Some IMF foods contain high level of additives that
may cause health concerns and possible legal
problems.
 High sugar content is also a concern becouse of
high calorific value.
 Texture and flavour sometimes gets damaged if not
properlly handled.

14. Efforts should be made to improve the quality of such
foods by lowering the sugar and salt addition as well as
increasing the moisture content and aw but without
sacrificing the microbial stability and safety of products if
stored without refrigeration. This may be achieved by an
intelligent applications of hurdles.