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As a credible laboratory equipment distributor in Indonesia, Alterlab has committed that client satisfaction in the form of both company or researcher is our satisfaction. Over the years, we have maintained that commitment by increasing the service of the Alterlab team wholeheartedly and working with various world laboratory equipment manufacturing companies.
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[Guide] How to Avoid Color Changes in Preserves or Ready Meals after Pasteurizing or Sterilizing Them

When cooking, pasteurizing or sterilizing food, it tends to lose its color intensity. The orange of a carrot or pumpkin or the red of a strawberry also declines somewhat. That’s normal. Whether our food loses more or less color depends, in part, on its acidity level, that is, on its pH. The pH of an ingredient indicates its degree of hydrogen ion concentration. The more acidic a food is, the lower its pH value. The vast majority of foods are on a pH scale between 3 and 7.


  • If you think that the color of your canned vegetables is a little off you can add a little bit of baking soda.
  • You can also add some type of natural coloring that does not add any flavor. Or if you are looking to give a reddish touch with a smoky touch, you can add red paprika.
  • Add a drizzle of olive oil on the product before sterilizing it.
  • Hide the top layer of the canned or ready meal with a label so that the potential customer cannot see the difference in color. Let us remember that we are only talking about a certain darkening or browning that does not affect the quality of the product.

Excessive drying is another factor that can affect the aesthetics of our preserves. Some products dry out on top, especially if they are not covered by some type of solution (sauces or other liquids). This sometimes appears in preserves or ready meals, such as meatballs or meats cooked in sauce.

Our autoclaves have several features whose sole purpose is to respect the organoleptic and nutritional characteristics of your gourmet preserve or ready meal. And they do it by incorporating:

Importance of pH in the preparation of preserves and ready meals with an autoclave

  • A direct control over the F0-P0 value and thus optimizing the cycle time, which allows to have an exact control that we will do things well and without unnecessarily overcooking the food.
  • Possibility of programming a gentle cooking phase before pasteurization or sterilization. There is the possibility of introducing prepackaged raw or undercooked foods into the autoclave, doing a preliminary cooking phase at a low temperature, for example at 60°C for 30 minutes and then briefly sterilizing them at 110°C, all at once, so that you will save time and energy costs.
  • Fast cooling by means of a water shower at the end of the cycle. Once you get the F0-P0 values you have programmed, the equipment cools down quickly with water immersion, to minimize overcooking your product.
  • Control and regulation of the entire cycle by a heart temperature probe, and we always provide you with a perforator kit for both caps or semi-rigid containers to be able to insert the probe and perfectly control the temperature throughout the process.
  • Continuous monitoring of all sterilization parameters. In case of failure or not reaching the expected results, the program is interrupted and generates a warning message.