Tempered Glass is simply glass that has been strengthened during the manufacturing stage. There are several advantages to using tempered glass and it should be the only glass used in safety applications and applications that require a lot of temperature changes (such as freezing and heating).
Tempered glass is designed to be able to be frozen. Regular glass is not designed to withstand sudden and drastic temperature changes. When non-tempered (or regular) glass is frozen it has a large probability of breaking off into microscopic shards and entering your food.
When you heat non-tempered glass there are micro air bubbles and as they get hotter they will expand to the point where they blow up (trust me!). Because tempered glass has been treated to withstand heating there are no micro air bubbles that allow it to blow up. With ALL glass, tempered or not, it is still susceptible to thermal cooling shock. One example of thermal cooling shock is when a hot container is thrown in a bowl of cold water, it will break!
Continued proper use will not cause tempered glass to breakdown. It can go from the freezer to the microwave to the dishwasher six times a day and still obtain its strength. When non-tempered glass is used in such applications it is even more susceptible to breakage. Glass is made out of recycled glass. So even if you do break a container-put it in the recycling! One of the reasons that tempered glass is used in many safety applications (such as windshields) is that it breaks in a specific pattern that is less harmful than that of other types of glass. When tempered glass breaks, it breaks into small, circular pebble type pieces instead of breaking into shards and splinters that have sharp edges.
While tempered glass is superior to regular glass for food storage it is also superior to all other food packaging materials such as plastic, stainless steel, Styrofoam, and cardboard due to its recycling qualities as well as chemical compositions. Tempered glass is free of BPA, PVC’s, Phthalates +. Think of a plastic container with tomato sauce-the plastic will go into your food just as easy as the tomato sauce stains the plastic. That isn’t possible with glass because it is non-porous.
Are Commercial Baby Food Jars Tempered? Over the short course of business we have had many people ask us why we didn’t simply buy commercial baby food in glass jars and then reuse those jars. It is extremely important to note that commercial baby food jars are not tempered and therefore are not microwave or freezer safe!
This entry was written by Melissa, posted on August 6, 2014 at 5:33 pm, filed under Baby Product Safety and tagged food storage, glass education, glass food containers, glass safety, tempered glass, the more you know. Bookmark the permalink. Follow any comments here with the RSS feed for this post. Post a comment or leave a trackback: Trackback URL.
Yeah, the part about not being able to freeze non tempered glass, I learned that the hard way. I wish I would have come across this blog before hand. This was really helpful thank you for the information!
I would like to know if the lids to your wean kits are bisphenol-A (BPA), phthalate, and polyvinyl chloride (PVC) free?
I too would like to know if the lids are bisphenol-A (BPA), phthalate, and polyvinyl chloride (PVC) free.
I know your product is tempered glass, but what are the lids made of? Have the lids been tested for any estrogenic activity? Where would I find this information on the Wean Green website?
regular basis. It contains nice stuff.
I find it interesting that you talk about how tempered glass actually breaks along a specific patter. I had no idea about that and I’ve always wondered why this type of glass was used for stuff like windshields. I’ll have to keep that in mind next time I get a chip on my windshield because it could give me an indicator for when the glass starts to crack.
can tempered glass (microwave carousel dish) be recycled?