 Alternatively, in order to promote an unbiased analysis, bottles and even glasses may be disguised in a "blind" tasting, to rule out any prejudicial awareness of either vintage or winery.To ensure impartial judgment of a wine, it should be served "blind" – that is, without the taster(s) having seen the label or bottle shape.Blind tasting may also involve serving the wine from a black wine glass to mask the color of the wine.