Ferment noble rot and add energy for something sweet (9)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

An anagram (‘ferment’) of ‘noble rot’, for the chocolate brand. The surface refers to wines: ‘noble rot’, Botrytis cinerea ( pourriture noble or edelfäule ) is a mould which renders grapeskins porous, and the juice thus more concentrated, so that its sweetness may be used to make wines such as Chateau d’Yquem and other sweet Sauternes, and German sweet wines culminating in trockenbeerenauslese.