| 摘要 |
<p>The brown redn. of malic acid (I) to lactic acid (II) in wine by the addn. of large nos. of bacterial cells is improved by: (a) activating a concentrate of a bacterial culture (which has been grown in the presence of (I)) in an N source-augmented fruit juice to afford an activated mixt. of bacteria contg. at least 10 power 5 CFU/ml; and (b) the activated mixt. is introduced to wine or grape must to convert (I) to (II). - IN step (a), the concentrate (pref. preserved e.g. by freezing in the presence of glycerol, or by lyophilising) is pref. obtd. by centrifugation after growth on a medium contg. 0.01-1% (I), carbohydrate, N-source and minerals. Prefd. bacterial sp. is Leuconostoc oenos NRRL-B-15533 or NRRL-B-15534, and the concentrate contains at least 10 power 8 esp. 10 power 8-10 power 13 CRU/g. The fruit juice is pref. grape juice.</p> |
