myalcin
Member

I have some questions about

Stability problems of emulsions.

We have an intensive cream formulation. We have produced this formulation for many years. Some times we met some problems like that after packaging the water occurred in the package after a few days. But we couldn t see this problem first step . We do centrifuge test 5000 rpm 50 C 30 min. Although there is no problem when we do this test. We squeeze this product from the tube nearly after 2 months. We see water drops... we use protegin wx as you know this raw material is a mix oil phase that includes emollients, waxes and emulgators. So hlb balance must be correct. Why does the water drops occurre? How can we solve this problem? Could the cause of the problem the new generation preservatives?

Regards,

M.Yalcin

Stability problems of emulsions.

We have an intensive cream formulation. We have produced this formulation for many years. Some times we met some problems like that after packaging the water occurred in the package after a few days. But we couldn t see this problem first step . We do centrifuge test 5000 rpm 50 C 30 min. Although there is no problem when we do this test. We squeeze this product from the tube nearly after 2 months. We see water drops... we use protegin wx as you know this raw material is a mix oil phase that includes emollients, waxes and emulgators. So hlb balance must be correct. Why does the water drops occurre? How can we solve this problem? Could the cause of the problem the new generation preservatives?

Regards,

M.Yalcin

## Comments

Thanks for your interest. We use homegenizer 2 or 3 times for several minutes during cooling. We read the Evonik's document. Although our formula and process is same with the documentation, we have this problem. Can we save this finished product or is it a waste?

Could you see above photo. We met this problem sometimes. Can we save this finished product by applying something or is it waste? If we can save how can we do? And Your suggestion adding ultrez 1, can it be solved our problem? Sometimes our viskosity value arrives 130.000-150.000. I thing our problem is not viskosity problem for stabilitiy.

my first suggestion would be to find the drop point of the oil phase, and form the emulsion 5-10°C above that instead of at 80°C

There is also interesting thing. We tested this product as a bulk. We measured its viscosity value, pH, etc. And did centrifuge test at 3000 rpm, 50 C 30 min. the product passed all if these tests. And we filled it but after 5-6 months it would be like that How can we understand this problem before filling.

myalcinHi----it is time/temp dependent so you have to put at 50C for at least 4 weeks and monitor weekly;you should see it within two weeks at 50C,Centrifuge is only a short term indication and we would never market a product without doing the 50C for four weeks:you can also do 38C for three months and monitor monthly.It has never failed me with these types of products.Yes the formula is stable we know that. Because it passed from all of the stability tests(long time like 3 monts etc.) and yes I think we have problem at the process some times. Ok I wonder which fast quality control test method we must do after every batch in the production for finding this problem? Freeze/thraw test is too long. (six days) wait -10C 24 hours and wait normal room temp 20-25C 24 hours. This cycle must be 3 times for correct result. Can we do this test like that for one period wait -10C 12 hours and then 20-25°C 12 hours? or how can we find if there is the stability problem on my batch or not? Which another method is more quickly then this test? Thank you for your interesting.

Yes the formula is stable we know that. Because it passed from all of the stability tests(long time like 3 monts etc.) and yes I think we have problem at the process some times. Ok I wonder which fast quality control test method we must do after every batch in the production for finding this problem? Freeze/thraw test is too long. (six days) wait -10C 24 hours and wait normal room temp 20-25C 24 hours. This cycle must be 3 times for correct result. Can we do this test like that for one period wait -10C 12 hours and then 20-25°C 12 hours? or how can we find if there is the stability problem on my batch or not? Which another method is more quickly then this test? Thank you for your interesting.

You should also try to make the stability tests a short time before filling the tubes.