1857 The Bordeaux wine and liquor dealers' guide

29

!dANUFAafURING AND ADULTERATING LIQUORS.

solutions that spontaneously run into the state offer– mentation, the ferment is supplied by nature, and is intimately associated with the saccharine matter. In suchcases, the nitrogenous matters present are thefirst to suffer decomposition or fermentation; and this par– ticular motion of their atoms is communicated to the sugar, and continues till the latter has entirely disap– peared from the liquid, or the former is wholly pre– cipitated in the shape of decomposed yeast or fer– ment. In those vegetable solutions which scarcely pass into the state of fermentation, or among whose molecules such changes progress slowly and irregu– larly, there is a deficiency of nitrogenized matters or exciters of fermentation, and it becomes necessary to add a ferment. Recently expressed grape-juice (must) offers a lively instance of the former class of substances; and infusion of malt (wort) of' the latter. When grapes are squeezed in the air, the limpid juice soon manifests the usual symptoms of fermentation, the liquid becomes turbid, carbonic acid gas is de– veloped, and the nit~ogenized principles which the juice previously contained are decomposed and pre– cipitated under the form of ferment, which immedi– ately induces the decomposition of the sugar ; and this state continues until the whole of' the yeast is precipitated in an insoluble and inert form, or the whole of the sugar is decomposed. In the juice of

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