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  • Water appeared when stability testing with Warm Oven

    Posted by hobbiz on June 22, 2021 at 6:13 am

    Hi.
    I tried 30days at 45oC stability test for my emulsion, in my Warm Oven. After a few days, there is a lot of water inside my samples. I even tried with other commercial brand emulsion and results are the same. 
    I put a therometer inside the oven and humidity is about 40-45%.
    Please help, why there is so much water inside the sample’s jars? The emulsion seem to be still stable, not seperated.

    Thank you.

    hobbiz replied 3 years, 4 months ago 2 Members · 2 Replies
  • 2 Replies
  • EVchem

    Member
    June 23, 2021 at 4:37 pm

    ambient humidity/ condensation can pool on top of the product- do you trust the instrument you got the humidity readings from?  For me I’ll ignore a ‘small’ amount of water on top, but it’s really up to each individual to decide where to draw the line. I’ve wondered about letting the samples come back to room temp and then pouring out excess water, not sure if that would be helpful or hide an underlying problem.

    Accelerated stability is a double edged sword- it shows some potential issues you might see during a products real time shelf life, but the heat can also cause some reactions/results that might not normally occur under standard conditions. That’s why stability protocols will include accelerated stability but still perform real time room temperature testing to get the best overall picture of a product.

  • hobbiz

    Member
    June 29, 2021 at 5:10 pm

    Thank you. Probably I need a better humid meter or a good aging oven :(

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