Canning and Fish Packaging Technology

Unit 3 - Unit operations in canning

3.2.6.1.Defects arising due to improper cooling

• Cold spot during heat process acts as a hot spot during cooling and hence leads to over processing in this area resulting in loss of nutritional and sensory quality, also undesirable chemical changes take place.
• Optimum temperature is provided for the thermophiles to grow leading to thermophilic spoilage such as flat sour spoilage.
• Large struvite crystals are formed due to slow cooling. Small crystals are not noticed, but large crystals are noticed and they are objectionable. This is a problem in crab meat and some variety of tuna.
• Results in stack burning due to slow and insufficient cooling.
• More internal corrosion problems ultimately leading to holes in the tin plate, more hydrogen gas production and loss of vacuum.