Sue Huml, IBCLC, LLLL
Director of Education Lansinoh Laboratories

Yes I am out here and will endeavor to answer the comments and questions that
have been posted over the weekend.  I have consulted with a PhD Chemist with
extensive lanolin experience to answer your questions regarding shelf life and
oxidation of Lans--oh.  I do not think that most of these answers would apply to
ordinary USP lanolin or other grades of lanolin.
Lans--oh is NOT a fat and is not prone to rancidity.
Oxidation of lanolin can occur but this usually only affects a very shallow
surface layer (exposed to air).
It is quite true that a distinctive "lanolin" odor accompanies the surface
oxidation of lanolin.  Oxidation of lanolin involves the conversion of some of
the free alcohols into ketones.  As Lans--oh contains a very very low level of
free alcohols (below 1.5%) compared to other lanolins, it is even less prone to
oxidation than other lanolins would be. Unused Lans--oh in sealed tubes would
not be exposing any of the material to air therefore oxidation in unopened tubes
would be highly unlikely.
Lans--oh is packaged with a three year shelf life (unopened)   - This is a
period of time for which the material ought to be expected to remain within its
analytical specification and not a period of time after which the material
should be considered no longer safe to use.
Once the tube is opened, keeping air out of the tube will make oxidation even
less likely.
The delelopment of a stronger odor can be an indication of surface oxidation.
Because the oxidation tends to be confined to a small surface layer, melting and
mixing could have a "renewing" effect.
Hope this answers your questions. Any others feel free to e mail me.
Sue Huml, LLLL IBCLC