Barrel Toasting with Infrared Heat
Fire toasting is the most commonly used method to toast wine barrels however, we can also toast barrels using infrared heat in one of our infrared toasting apparatus.
After seeing the infrared toasting machine clients often ask, “What is the difference between an infrared toast and toasting over a fire? Isn’t heat…heat?” The answer is, not exactly. But with that question in mind, we thought it might be interesting to write a post about electromagnetic radiation and how we harness that science to do something a little bit different within some of our wine barrels.
Radiation is a form of heat transfer which exists in quite a broad spectrum. In fact, the tool which we use to classify radiation is known as the electromagnetic spectrum.
The electromagnetic spectrum depicts the variance of electromagnetic waves as it relates to their frequency or wavelength. It just so happens that as the wavelength varies so does the total energy. As the wavelength of electromagnetic waves become shorter, the amount of energy carried by the waves intensifies. The intensity varies greatly across the spectrum.
Next, we should define a term known as absorptivity. In heat transfer, absorptivity is a term that describes how well an object or material absorbs electromagnetic radiation. The absorptivity of an object will change depending on the wavelength of the radiation it is being subjected to and can be measured along a scale of 0 to 1 (correlating from 0% absorbed to 100% absorbed.) This fact is key for our purposes. We can use human skin as a great example. The sun emits radiation across three different bands: infrared, visible and UV radiation. It just so happens that our skin is significantly more reflective than it is absorbent across the visible and infrared bands but more absorbent of UV radiation emission. This is one reason why UV radiation is hazardous to our skin.
In much the same way our skin absorbs one wavelength and reflects another, the absorptivity of the oak wood in our barrels can vary depending on the type of radiation we apply to it, whether fire or infrared. This is the essence behind our infrared toasting machine. We have designed a toasting apparatus that differs from oak fire toasting in two main ways:
- It operates across a different range of the electromagnetic spectrum
- We can precisely vary the wavelength since we have multiple emitters attached to the apparatus that function at different wavelengths
We can utilize various wavelength combinations to create new, unique profiles within our Profile series. For example, shorter wavelengths penetrate the surface of the wood and toast deeper within the wood layers, whereas longer wavelengths reflect more, and thus, toast the outer layers of wood. Utilization of this technology also allows us to create high impact barrels without smoke – something that can be quite challenging to do with fire toasting. Infrared toasting is a very precise method of toasting that creates high levels of consistency for our winemakers. It is not more beneficial than toasting with fire, or vice versa. They are simply different ways of treating the barrel to bring about new and varied flavor profiles.
We currently offer three barrels in our Infrared toasts: Aroma, Reflection and Dimension. To learn more about our infrared toasted profiles contact your World Cooperage Account Manager.