Glass Bakeware

Glass 101 – About the Types of Glass Used in the Kitchen

About the Types of Glass Used in the Kitchen
Soda-Lime vs Tempered vs Borosilicate Glass

There is a growing trend to move away from plastic food containers and metal bakeware, and there are many good reasons for doing so. However, the more we explore this option, the more it can become confusing. There are different types of glassware available. So, the question remains…Which one is best for me? This article explores the different types of glassware available today, so that you can make an informed decision on what type of glassware is best for you.

About the Different Types of Glass for Kitchen Use
Not all glass is created equal. However, each type has its own advantages and potential drawbacks. Which type of glass is best to buy will depend on your intended use for the item itself. The following should help you when shopping for glass items for your kitchen.

Components of Glass. All types of glass contain silicon dioxide, boron trioxide, sodium oxide, and aluminum oxide. However, the proportions of each chemical vary between glass types. The chemical composition affects the strength and melting points of glass. There are three types of glass that can be found in the kitchen: Soda-lime, tempered, and borosilicate glass.

About the Annealing Process. Annealing is a process of heating and cooling glass at a controlled rate during manufacturing. This step improves the glass’ durability and helps to reduce internal stresses that could cause breakage when the glass is heated and cooled during normal use. Annealed glass may be referred to as non-tempered glass or float glass. Annealed glass is not as strong as tempered glass. When annealed glass gets broken, it breaks into sharp, jagged pieces that could hurt someone nearby. When tempered glass gets broken, it breaks into small, smooth, relatively harmless pieces.

Since annealed glass does not go through extensive processing, it is cheaper to make than tempered glass. Annealed glass has optimal versatility for the manufacturer, so it can be crafted in many styles and designs, allowing it to be customized in many ways.

Soda-Lime Glass
Soda-lime glass is the most common type of glass. It may also be referred to as “soda-lime-silica glass” and may also be referred to as “annealed glass” since it is put through the annealing process. This glass is usually used for windowpanes, light bulbs, and glass containers like bottles and jars for beverages, food, and some commodities. Mason jars are made of soda-lime, annealed glass. Because of its chemical makeup, soda-lime glass is not as strong as other types of glass and will break easily when subjected to being bumped, or sudden extreme temperature changes (also known as thermal shock). While any glass can break with extreme sudden temperature changes or mechanical bumps, soda-lime glass will break the easiest under such conditions. It is relatively inexpensive to make, so it would be the preferred glass to manufacture. About ninety percent of manufactured glass is soda-lime glass. Soda-lime glass does not contain as much silicone dioxide (69%) as does borosilicate glass (80.6%).

Soda-lime glass is smooth and nonporous, allowing it to be easily cleaned. It resists chemicals in water solutions, so they will not contaminate the contents nor affect the flavor of anything stored in the glass. However, soda-lime glass does not tolerate very high temperatures, sudden temperature changes, or being bumped mechanically without cracking, chipping or breaking. For example, it can break when exposed to a sudden temperature change, such as when pouring very hot liquid into a cool glass.

Tempered Glass
Tempered glass is soda-lime glass that has been specially treated to make it stronger and more durable. In the manufacturing process, soda-lime glass is subjected to extremely high temperatures, followed by a few seconds of a high-pressure cooling technique called quenching. Tempered glass can also be created through chemical treatment causing the glass to compress. However, the chemical process is expensive and not used very often. When tempered glass shatters, it breaks into small pieces, making it less likely to cause injury than when untempered soda-lime glass shatters.

Tempered glass is very durable and resists smudges, allowing for easy removal of fingerprints. It is much harder and stronger than untempered soda-lime glass, and can tolerate temperatures up to 470°F. However, despite its strength, tempered glass should not be subjected to sudden extreme temperature changes, which could cause it to shatter. An example would be removing a glass bakeware dish with food in it from a 450°F oven and placing it on a cold marble slab or countertop. After removing a hot glass baking dish from the oven, place it on dry hot pads, towels or trivets that will absorb the warmth of the dish rather than shocking it with a much cooler temperature. A lot of glass bakeware is currently made from tempered soda-lime glass.

Borosilicate Glass
In addition to the other components, borosilicate glass contains boron trioxide. This ingredient makes the glass very strong so it is unlikely to crack when exposed to extreme temperature changes. It is also very resistant to chemical corrosion. Therefore, borosilicate glass is harder, stronger, and more durable than soda-lime glass, tempered or not. This type of glass is used in some bakeware since it can tolerate extreme temperature changes far better than tempered soda-lime glass. It is also used in pipelines, sealed-beam headlights, and laboratory equipment. Interestingly, borosilicate glass is more likely to break when dropped than tempered soda-lime glass. When it breaks, it shatters into large sharp pieces that can cause serious injury to anyone nearby.

So, the question remains…Which brand is made of which type of glass, and which type of glassware is best for me?

You will need to be the judge on which type of glass bakeware is best for you, based on your personal needs, applications, and habits. The following information gives insight to some of the common brands of glass bakeware currently on the market.

Pyrex (World Kitchen) Glassware
Many of us own Pyrex glassware. The company was established in 1915 and originally made its glassware products with borosilicate glass. In recent years, corporate changes took place and newer products have since been made with tempered soda-lime glass. As a consumer, you can easily determine which type of glass your glassware is made from by looking at the brand name. If it is spelled in all capital letters (PYREX), it was made with borosilicate glass. If it is spelled in all small letters (pyrex), it was made with tempered soda-lime glass. Any newer borosilicate PYREX glassware is currently being made in Europe.

Anchor Hocking Glassware
This brand of glass bakeware is made of tempered soda-lime glass.

Libby Glassware
Libby glass bakeware is made of tempered soda-lime glass.

1790 Brand Glassware
This brand of glassware is made of borosilicate glass.

Amazon Basics Glass Bakeware
This brand of glassware is made of borosilicate glass.

OXO Glass Bakeware
This brand of glassware is made of borosilicate glass.

How to Minimize the Risk of Breakage
Glass bakeware comes with instructions for use and care. We should all read the paperwork that comes with such things, and follow the instructions carefully. But many times, the paperwork gets tossed aside and never read. So, here are some general tips for the safe use of glass bakeware.

* Avoid extreme changes in temperature, such as taking glassware directly from the freezer to a hot oven, or from a hot oven to the sink. Care should also be used when placing a frozen glassware item into the microwave.

* Do not add liquid to hot glassware. Allow it to cool down first.

* Do not place hot glass bakeware on cold or wet surfaces, countertops, or stovetops. Instead, place them on a dry towel or hot pads, wooden cutting board, cooling rack, or trivets designed for hot glass items.

* Do not put hot glassware into the refrigerator or freezer. Allow it to cool down first.

* Do not use glassware on the stovetop, under a broiler, or in a toaster oven.

* Do not heat empty glassware.

* Always preheat the oven first before placing glassware (WITH FOOD IN IT) in the oven.

* Don’t use glassware to microwave popcorn or heat food that is in browning wrappers.

* When heating cheese, oil, or butter in glassware in the microwave, don’t overheat it. Heat it only for the minimum time needed.

* Allow glass bakeware to cool completely before immersing it in water.

* Use care not to bump, poke, or scratch glass bakeware with utensils of any type.

* Do not use glass bakeware that has any chips, cracks or other damage, which can cause them to suddenly shatter.

* Do not microwave nearly empty glassware. Be sure it has ample food in it to absorb the heat generated by the radiation from the microwave.


Resources

https://www.nytimes.com/wirecutter/blog/tempered-vs-borosilicate-glass/

https://www.thespruceeats.com/best-glass-storage-containers-4154183

https://healthy-cookware.com/why-glass-food-storage-containers-are-better-than-plastic/

https://icedteapitcher.myshopify.com/blogs/news/how-can-you-tell-if-pyrex-is-borosilicate

https://www.westlab.com/blog/2017/11/02/what-is-the-difference-between-soda-lime-glass-and-borosilicate-glass

https://www.dillmeierglass.com/news/what-is-annealed-glass

https://www.bullseyeglass.com/what-is-annealing-why-is-it-necessary.html

https://www.m3glass.com/blog/tempered-vs-annealed/

https://www.materialshub.com/material/soda-lime-glass/

https://www.lenntech.com/glass.htm

https://www.onedayglass.com/annealed-vs-tempered-glass-difference/

https://gizmodo.com/the-pyrex-glass-controversy-that-just-wont-die-1833040962

https://www.dontwasteyourmoney.com/best-glass-bakeware-set/

https://pittsburgh.cbslocal.com/2011/09/06/consumer-reports-tests-glass-bakeware/

https://www.thespruceeats.com/glass-bakeware-safety-tips-1907162

https://www.amazon.com/Piece-Glass-Food-Storage-Container/dp/B01IU416YG

https://www.walmart.com/ip/1790-Glass-Food-Storage-Containers-with-Lids-Glass-Meal-Prep-Containers-Airtight-Glass-Lunch-Boxes-BPA-Free-FDA-Approved-Leak-Proof/921652275

https://www.amazon.com/dp/B076HZFG41?th=1

https://www.amazon.com/AmazonBasics-Oblong-Baking-Dishes-BPA-Free/dp/B08BS692GS/ref=sr_1_1_sspa?dchild=1&keywords=glass+bakeware&qid=1622758294&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyUUFTQ0VYREtRWElaJmVuY3J5cHRlZElkPUEwNDAyODEyMVpWTFpYQVg4Ujk0NSZlbmNyeXB0ZWRBZElkPUEwMjQ1MTM0SDVNUUdPUjVXNlo3JndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

https://www.amazon.com/OXO-Grips-Freezer-Oven-Baking/dp/B019FHD0FK/ref=sr_1_12?dchild=1&keywords=glass+bakeware&qid=1622758418&sr=8-12

https://worldofpans.com/can-you-put-pyrex-in-oven/

https://cooking.stackexchange.com/questions/68317/why-must-the-oven-be-preheated-for-a-pyrex-glass-pan

https://12tomatoes.com/limitations-pyrex-cookware/

https://www.tasteofhome.com/article/pyrex-dish/

 

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