indisciplinato ha scritto:Due domande.
I prefermenti con LDB danno sempre nervo all'impasto oppure questo dipende dalla misura del lievito iniziale? Io ricordo una discussione - temo scomparsa - dove con Ramirez era emerso che la misura del lievito poteva ora favorire effetti riducenti, ora irrigidire la funzione viscoelastica del glutine (acido succinico).
I prefermenti "sponge" non sembrano essere precisamente codificati come accade per poolish o biga. Cosa sono? Coincidono con le indicazioni di Hamelman?
Non saprei rispondere alla prima domanda...
Per lo sponge cito M.Suas
"Sponge Originally, sponge was used as preferment in pan bread produc-
tion in England. Today, the sponge process for pan bread production has
largely been replaced by the straight dough method, with dough condi-
tioners replacing the sponge. Sponges were also, and still are, used in the
production of sweet dough in other European countries as well as the
United States.
The sponge process is similar to the poolish process; it differs pri-
marily in dough hydration. While poolish has a liquid consistency, the
absorption of sponge is around 60 to 63 percent, creating a stiffer con-
sistency that makes the dough easier to handle. Like poolish, the sponge
usually does not contain salt, and the quantity of yeast is calculated
depending on the length of the fermentation. In fact, the yeast guide-
lines for a poolish can be applied to the sponge process. When it comes
to taste, sponges and poolish generate very similar aromas; however, it
tastes slightly sweeter than the poolish.
A sponge should be used after it has reached full maturation.
Its surface contains vital clues to help the baker determine its readi-
ness, including numerous bubbles and the formation of cracks that cre-
ate some collapse. At this point, the sponge is ready for incorporation
into the fi nal dough. An undermature sponge will not be as beneficial
because of inadequate acid development, whereas an overmature sponge
will have too much, negatively affecting the strength of the dough and
the fl avor of the bread. (See Figure 4-5.)
A sponge that uses minimal yeast and ferments overnight offers the
baker a longer period of time between undermaturation and overmatu-
ration. This longer fermentation time generates enough acidity to ensure
good fl avor and a longer shelf life.
A sponge can be used in many products. Sweet dough will get the
most benefi t from the sponge method because the stiffer consistency of
the sponge improves the strength of the dough. This increase in strength
is usually enough to compensate for the potential weakening of the glu-
ten that is created by the sugar and fat frequently found in sweet bread
formulas."
In merito alla tua prima domanda
"There are two other advantages worth mentioning. First, when
the quality of the fl our is not optimal, preferment can be a great help
in strengthening the dough and compensating for flour deficiencies."
