Sweetened Condensed Milk Ii Longevity Brand Sweetened Condensed Milk 14 Oz Walmartcom
Casein May be defined as the major protein which is precipitated at pH 4.6 and is exclusive to milk. It is present in spherical bodies as micelles which vary in size with negative surface charge. The caseins of milk may be sub-divided into five main classes αs1 αs2 β gamma and k-caseins. In milk casein is present in combination with calcium in the form of calcium caseinate or more precisely calcium hyhdrogen caseinate. Whey proteins Are those in the whey fraction after the precipitation of casein at pH 4.6. These are the alpha-lactalbumin beta-lactoglobulin immunoglobulins lactoferrin transferrin proteose-peptone fractions etc. Most of these are globular proteins subject to heat denaturation. α-lactalbumin exists in variants A and B forms and is susceptible to denaturation by unfolding of the tertiary structure. β-lactoglobulin is identical to blood globulin and insoluble in water and is responsible for the transfer of antibodies.
You can reduce your risk by initially setting a limit of $10 rather than $20 but if you are not comfortable with a little risk and taking a small loss of some of the bottles you buy then this is a sub-niche you should avoid. Here are some additional general hints & tips to remember when purchasing these bottles...Never buy a bottle that has any chips or cracks no matter how small or seemingly insignificant. The condition of the Pyro-Glaze design is extremely important - avoid any bottles that have chipped faded or scratched Pyro-Glaze as well. These bottles were to be used and then returned to the dairy where they were cleaned and reused. After extended use and cleaning some developed numerous small scratches to the glass. You should avoid bottles that exhibit severe scratching.
You can find some good information regarding how to identify reproductions along with some pictures of known reproductions from various online sources. If you are interested in learning more about these bottles there are two books currently available that provide some excellent information about how they were made and used along with some basic pricing information. The book are titled "Udderly Beautiful" and "Udderly Splendid" by John Tutton. Both give some rarity and pricing information but because of the large number of bottles produced they don t cover even a small fraction of the bottles produced. Both can be found for sale on either eBay Amazon or in some antique shops. Other sources of information are The National Association Of Milk Bottle Collectors and the individual web sites many of their members maintain.