Your aim in preparing the must and in the fermentation of honey should be to retain as much of the natural flavor and aroma of the honey as possible. Honey is a dense and sticky product, which makes it quite difficult to work with. You will need to dissolve the honey in water so the must is easy to pour and stir. There are several options that a mead-maker can employ that will dissolve the honey and sterilize the must at the same time. Each of these methods have pros and cons. Apparently, the Chinese pasteurized rice wine to preserve it as early as 1117!
I used to pasteurize my honey but do not any more. Now I cold-process my must – the most heat I apply is to warm the water enough to liquefy and mix the honey. I am counting on the might of modern lab-generated brewing yeasts, well-nourished and coddled, to overcome any wild yeasts present. I don’t think I’ve ever used sulfites in a mead, though one of my local brewing shops has recommended potassium sorbate to stabilize the mead. We all want to avoid bottle bombs!
Commercial honeys that have been pasteurized were heated to 161F; that temperature increases the level of hydroxymethylfurfural (HMF) and reduces enzyme (e.g. diastase) activity. Heat also affects appearance (darkens the natural honey color), taste, and fragrance On the other hand, raw honey does tend to have a good deal of wild yaest in it. So if you’re going to:
Boiling: The goal is to pasteurize your honey as a means to killing off any wild yeasts present. There are guaranteed to be some unless the honey’s already been pastuerized, and commercial honeys have generally been heat-treated but not pasteurized.
Heat some water in a stainless-steel pot. Once the water is at a very warm temperature, just below the boiling point, it is removed from the heat and the honey is added. The mixture is stirred to dissolve the honey and then placed back over the heat. The must is brought to a boil and the scum that forms on top is scooped off. This scum mostly consists of coagulated proteins and beeswax. After a brief period the must is removed from the heat and allowed to cool, or more water is added to bring the temperature down more rapidly. The trick to boiling is to know pasteurization timetables.
Advantages: The must is sterilized and any bacteria or wild yeast present will be killed. In addition, protein compounds are boiled out of the honey mixture, leaving less chance of a protein haze in the finished mead.
Disadvantages: The flavor and fragrances of the honey will most often be cooked out of the must, leaving your finished product with very little of either. Possible color change.
Heating: In this method, water is heated to 180F or to just below boiling, and the honey is diluted in the hot water. This method is similar to pasteurization. The temperature is held at this temperature for 20 to 30 minutes. When I heated my honey, I would bring it to 145F for 22 minutes, balancing time with low temperature in an effort to do as little damage to my honey as I can.
Advantages: As with boiling, the must is sterilized and any bacteria or wild yeast present will be killed. Some of the protein compounds will also be removed, although some may remain.
Disadvantages: As with boiling, some of the honey characteristics can be lost, as well as some of the subtle aromas. The color of the honey may change. Some of the protein compounds are heated out of the must, but not all of them, so fining may be needed to clarify.