This document discusses common defects that can occur when making jams and their solutions. It identifies causes and preventions for crystallization, bubbles, products being too soft, darker color, mold or fermentation, loss of color, and sticky or gummy textures. Common causes included excess sugar, overcooking, air bubbles, and improper storage. Preventions included accurate recipes, quick cooking, removing foam, proper sealing and storage in cool, dry, dark places.

2. Group members
• M Umar Riaz
• 16-uglc-639
• Zahid Hera
• 16-uglc-637

3. DEFECTS OF JAMS AND
THEIR SOLUTION

4. Formation of crystallization
• Cause
• Excess of sugar, undissolved sugar , mixture cooked too slowly or too long
• Prevention
• Use tested recipe and measured ingredients accurately

5. Bubbles
• Cause
• Air become trapped in hot jam
• Prevention
• Remove foam from jelly or jam before filling jars
• Pour jelly quickly into jars
• Don’t allow jams to start layer on the surface

6. Too soft
• Cause
• Over cooking
• Using too much water
• Moving product too soon
• Prevention
• Avoid over cooking
• Use only sufficient amount of water
• Cook rapidly

7. Darker than normal color
• Cause
• Over cooking
• Store too long at high temperature
• Prevention
• Avoid long boiling
• Store in cool , dry and dark places
• Refrigerate after opening

8. Mold or Fermentation
• Cause
• Yeast and mold grow on jelly
• Imperfect sealing
• Improper storage
• Prevention
• Test seal before storing
• Use new flat lids
• Use ring band in good condition
• Store process jars in cool ,dry and dark places

9. Loss of color
• Causes
• Improper storage
• Prevention
• Store processed jars in dark, dry and cool places

10. Sticky ,gummy products
• Causes
• Overcooking
• Prevention
• Follow recommended direction for each product
• Cook only until syrup is quite thick and fruit is fairly translucent