This document provides information on signs of spoilage in various foods including fish, meat, poultry, dairy, cereals, vegetables, fruits, and eggs. It describes changes in texture, color, smell, and appearance that indicate spoilage for each food type. The document also provides detailed instructions for testing eggs for freshness and spoilage by examining the shell, listening for sloshing, floating in water, smelling after cracking, and inspecting texture and color of yolk and white.

1. By:
Dr. Waleed Foad
MSc.Public Health in Nutrition
Clinical Nutrition Specialist
European Society of Gastrointestinal Endoscopy (ESGE)
Member of the American Society of Nutrition
Email: wfoad@outlook.com

2. Signs of Spoilage
in Fresh and Dry Food
Vary with type of Food
Generally:
Change in Texture: Softening or Hardening
Change in Colour: e.g. Discolouration, Mould Growth
Change in Smell e.g. Putrid, alcoholic, acidic..
Oozing out of fluid.
Fermentation or curding.
Presence of visible foreign material e.g. Insects, mould, metals

3. Spoilt Fish
Shows one or more of the Following:
 Gills are Gray or green.
 Dull or Sunken eyes.
 Bad Smell.
 Is Flabby and Flesh Separates from the bone.
 When outer surface is pressed, finger
depression remains in flesh.
 Few scales are left on fish

4. Good Looking Gills Fish

5. Spoilt Fish

6. Spoilt Meat and Poultry
When Surface area is increased, Spoilage
becomes more easier.
Organ meats (as Liver, Kidney and Brain) are
more perishable than muscle meat.
Signs of Spoilage:
 Discoloration.
 Bad Smell.
 Slimy appearance
 Flabby texture
 Microbial growth (colonies)

7. Spoilt Meat

8. Spoilt Poultry

9. Milk and Dairy products
Shows spoilage signs of one or more of the
Following:
 Change in taste to sour or bitter milk.
 Frothy or bubbly surface of milk.
 Curd formation (mostly when heated)
 Butter tastes rancid.
 Cheese develop off odours, mould growth and
become slimy.

10. Spoilt Milk and Dairy products

11. Bread ,Cereals and pulses
These food types don’t spoil easily
When spoilt, signs as the following may appear:
 Musty odour and off taste
 Presence of pests or insects, e.g. Beatles,
worms,...etc
 Clumping of whole grains.
 Contamination with dirt, mud and stones
 Mould over growth.

12. Spoilt Cereals and pulses

13. Food contaminated by pests (A Mouse)

14. Vegetables and Fruits
When spoilt or contaminated, signs as the
following may appear:
 Presence of mould (some times rottening)
 Presence of insects, e.g. Beatles, worms,...etc
 Green leafy vegetables are wilted or shrunk
 Discolouration and altered texture.
 Skin or peel is bruised or damaged.
 Contamination with dirt, mud and stones

15. Spoilt Vegetables and Fruits

16. Food contaminated by pests (Frogs)

17. Eggs
 Recognizing 2 different issues:
1. Fresh from Stale (non-Fresh) eggs.
2. Spoilt eggs

18. Eggs
 The Egg Shell
integrity is the main
protector against
Spoilage and the main
Spoilage indicator in
the whole egg
 Generally, Safe Eggs are:
1. Kept refrigerated, and
2. are not broken,
3. Used with in 1 month of the Package date.

19. Testing Eggs: 1
1- See Package Date
 Eggs that are kept
refrigerated and are not
broken should be good
for at least 1 month
beyond the Package
date.

20. Testing Eggs: 2
2- Hold the egg up to your ear and shake it,
listening for a sloshing sound
 As the egg ages, moisture and
carbon dioxide escapes through
the shell, the yolk and white
begin to dry out and shrink,
and the air pocket in the egg
becomes bigger.
 A larger air pocket gives the egg more room to move
around inside the shell and create a sloshing sound.
 A sloshing egg only indicates that the egg is old and does
not mean the egg is unsafe for consumption.
 http://www.ochef.com/789.htm

21. Testing Eggs: 3
3- Place the egg in a bowl or a glass of cold water and see if
it floats.
 There is a tiny air pocket inside
eggs, and over time more
air passes through their
porous shells and into the egg.
 If the egg lays on its side
on the bottom of the bowl,
it is at peak freshness.
 If the egg stands upright on one end but is still touching the
bottom, it is aging but is still safe to eat.
 http://www.ochef.com/789.htm
 http://simmerandboil.cookinglight.com/2013/08/28/can-i-use-expired-
eggs/#sthash.k0mefnAr.dpuf

22. Testing Eggs: 3 cont.
3- Cold water Float test.
 If the egg is floating, it is not
a fresh egg.
 Stale (non-Fresh) eggs
float in Water.
 This does not necessarily
mean it’s bad or unsafe to eat. You should test the egg
by cracking it open and looking for (or smelling) signs
that it has gone bad
 http://www.ochef.com/789.htm

23. Testing Eggs: 4
4- Break and Smell
 Break the egg open and
notice if it smells.
 Best indicator of a bad egg.
 A bad egg will have a pungent,
foul odor when you break it open.
 The sulfurous smell will be obvious
as soon as the egg is cracked
(and possibly before), and the egg should be thrown out.
 A bad egg will have this foul smell, regardless of whether it is raw or
cooked
 http://cooking.stackexchange.com/questions/47036/egg-safety-when-to-
eat-and-when-to-not-eat
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-
answers/food-safety-fact-sheets/egg-products-preparation/shell-eggs-from-
farm-to-table/CT_Index#32

24. Testing Eggs: 5
5- Break and See Texture.
 Crack the egg open on a plate and check the quality of the
yolk and white.

25. Testing Eggs: 5 (cont.)
5- Break and See Texture.
 An Old Egg spreads or seems a little watery has a thinner
white.
 An Old Egg yolk is flat and breaks easily, and moves around
easily.
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-
education/get-answers/food-safety-fact-sheets/egg-
products-preparation/shell-eggs-from-farm-to-
table/CT_Index#32

26. Testing Eggs: 6
6- Break and See color.
 Break the egg open and
notice its color.
 The color of the yolk, in shades of
yellow or orange, has nothing to do
with freshness of the egg.
 Instead, inspect the egg white, or albumen.
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-
education/get-answers/food-safety-fact-sheets/egg-products-
preparation/shell-eggs-from-farm-to-table/CT_Index

27. Testing Eggs: 6 (cont.)
6- Break and See color.
 Egg white, or albumen.
 If it is pink or green, the egg has been contaminated by bacteria
and is not safe to eat.
 If black or green spots, it has been contaminated by fungus and
should be thrown away.
 A cloudy white indicates a very fresh egg. A clear white means the
egg is older (but may still be edible)
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-
answers/food-safety-fact-sheets/egg-products-preparation/shell-eggs-from-farm-
to-table/CT_Index

28. Testing Eggs: 6 (cont.)
6- Break and See color.
 Egg yellow, or yolk:
 If the yolk of a hard-cooked egg has a green ring around it, this means the
egg has been overcooked or was cooked in water with a high iron content.
This egg is still safe to eat.
 If there is a blood or meat spot in the egg, it is still safe to eat and does not
mean the egg is contaminated or has gone bad. A blood spot occurs when a
blood vessel ruptures when the egg is forming and has nothing to do with
freshness.
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-
answers/food-safety-fact-sheets/egg-products-preparation/shell-eggs-from-farm-to-
table/CT_Index
 http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-
answers/food-safety-fact-sheets/egg-products-preparation/shell-eggs-from-farm-to-
table/CT_Index

29. Spoilt Eggs
 Suspicion should raise when:
1. Cracked Shell
2. Leaking Contents.
3. Egg yolk is exposed.
4. Shell has an obvious discoloured dirty shell.
5. Bad Smell.
6. Eggs kept out of refrigerator for 2 hours or more, after
being refrigerated.
 Once an egg has cooled in your refrigerator, it is important to
keep it at the same temperature.
 A cold egg in a warmer environment begins to sweat, which can
encourage bacteria to grow on the outside of the egg. Because the
egg shell is porous, it is sometimes possible for the bacteria on
the shell to pass into through and contaminate the egg.
 http://www.eggsafety.org/blog/safe-handling/224-safely-store-
your-eggs

30. Spoilt Eggs

31. For Further Support:
Dr. Waleed Foad
Email: wfoad@outlook.com