Looking Past Steel: Glass-Ceramics for BBQ Applications

Barbecue grills are a ubiquitous part of summer. However, many modern grills rely on stainless steel lids which are used to trap heat, control smoke, and must be lifted to monitor the food. This leads to heat leakage, impedes the grilling experience, and requires constant vigilance. NEXTREMA^® glass-ceramic lids and viewing windows can solve this problem as they can withstand high temperatures, are shock-resistant, and easy to clean. Glass-ceramics can also be used as NEXTREMA^® Burner Shields in barbecues, offering benefits above standard metal shields. Of the options available in the market, NEXTREMA^® is seen to be the best choice and therefore a well-established material in the industry.

No summer is complete without a barbecue. Whether grilling your favourite meat, fish, some veggies, or something else, almost everything can be cooked on a grill. And grills come in all shapes, sizes, and price ranges. You can get one for as cheap as ten to twenty Euros or reach for one of the high-end luxury grills that can cost thousands of Euros. They can reach several hundred degrees Celsius and some high-end grills even have concurrent heat zones, allowing us to grill foods at high temperatures at the bottom while gently warming other foods on the top racks. 

Yet when it comes to the materials associated with grills, there isn’t so much diversity. Steel is probably the material that most often comes to mind. And while steel does make a good choice in many ways, it also reveals improvement options in some BBQ applications. So, what if there was a material that could enhance the grilling experience in an eye-catching way?

The issue with stainless steel lids

A good barbecue requires constant vigilance. Food should be monitored to make sure that it does not overheat and burn. At the same time, grilling is messy.

Grills, therefore, come with a lid or a ‘top’ that remains closed during most of the cooking. This ensures that heat and smoke are trapped inside, allowing for better cooking. However, it is very important that the grill master keeps an eye on the food being grilled. Just like the grill, BBQ lids are often made from metal - most often stainless steel, which is opaque.  This, in turn, requires opening and closing the lid repeatedly to inspect the food and, therefore, results in leaked heat and wasted energy.

Glass-ceramics offer a solution

Glass-ceramics can solve these problems easily, efficiently, and elegantly. With its high transparency and excellent optical and thermal properties, a glass-ceramic lid can help bypass the constant need to open it for food inspection, an obligation that other opaque materials would impose.

The transparent NEXTREMA^® glass-ceramic from SCHOTT AG can withstand temperatures of up to 925°C. They are highly thermal shock resistant for up to 800°C, which means that sudden changes in temperature due to opening and closing of the lid or even a quick rain shower would make no difference to their structural integrity. A normal soda-lime-silica glass could easily break under these conditions.  

 

NEXTREMA^® comes in curved, angular bent, and flat shapes, with different sizes and thicknesses to meet the customer's specific requirements. Even when there is no food inside, the sleek glass-ceramic surface is bound to be a head-turner.

NEXTREMA^® also makes excellent Burner Shields for the grill. This allows grillers excellent control and visual feedback about the flame (especially in combination with a transparent lid or window), allowing them to adjust the temperature of the grill, accordingly.

The smooth non-porous surface makes cleaning quite easy. In combination with intelligent lid design, dirt and residues on the Burner Shield can even be reduced to a minimum.

What makes NEXTREMA^® so efficient at handling high temperatures are the tiny ceramic crystals embedded inside their glass matrix. These crystals together take up less than a millionth of the total volume, but they ensure that the whole material has almost no thermal expansion. The graph below shows the per cent expansion of NEXTREMA^® as a function of temperature. The total expansion from 0 to 800 °C is less than 0.01%. 

Figure 1. The variation of the thermal coefficient of expansion with temperature. Notice that the expansion up to 700°C is less than 1.

 

The transparent NEXTREMA^® glass-ceramic is best suited for grill applications like lids, windows, or Burner Shields as they allow us to see directly into the grill.  

NEXTREMA^® tinted is also highly appreciated as a cover for side or rotisserie burners, not only in BBQs but also in kebab grills. 

Finally, NEXTREMA^® glass-ceramics come from SCHOTT AG, a company with 130 years’ experience in specialty glass and glass-ceramic. Let your products get the benefit of their ever-increasing technical capabilities and broad expertise in the glass industry and beyond.

Visit the SCHOTT AG supplier page for more information on their materials listed on Matmatch and to get in direct contact with them.