No tópico específico sobre fermentação primária, secundária..., Gunther defende que a elevação da temperatura na secundária deve ser de aproximadamente 1º por dia. De início essa taxa me pareceu razoável para não "estressar" o fermento. Depois eu me perguntei se realmente poderia causar estresse no fermento a elevação da temperatura. Como o fermento estaria entrando em faixas de temperatura mais altas que, em tese, são melhores para ele, por que isso lhe causaria estresse? Procurei no Yeast e não encontrei recomendação sobre essa taxa de 1º por dia.
Para trazer mais subsídios na discussão sobre esse assunto, encontrei no Brew Your Own desse mês a seguinte questão com a respectiva resposta do "Mr Wizard":
Ive seen the importance of diacetyl rests mentioned dozens of times. the description always states to increase fermentation temperatures to the 6568 °F (1820 °C) range for 2448 hours or so. However, there is never a discussion of how quickly to raise the temperature. If I have a lager at 50 °F(10 °C), do I raise the temperature only 23 degrees per day until I hit the range (adding ~7 days) to avoid shocking the yeast or do I raise it much faster to no ill-effect?
Seth Adams
Annapolis, Maryland
I have really never understood the idea of shocking yeast. Warming or chilling yeast within the temperature range that brewers ferment beer can and does occur quickly in commercial breweries without negatively affecting the yeast or the resultant beer. Fermenting too warm can of course lead to excessive production of esters, higher alcohols, sulfur, phenols, and other aromatic compounds, so controlling fermentation temperature is an important facet of brewing process control. The short answer to your question about the warming rate is not to worry about it. The easiest way to warm a batch of lager is to move your carboy from your lager fridge to a cool closet or corner in your basement and just let things happen.
Para trazer mais subsídios na discussão sobre esse assunto, encontrei no Brew Your Own desse mês a seguinte questão com a respectiva resposta do "Mr Wizard":
Ive seen the importance of diacetyl rests mentioned dozens of times. the description always states to increase fermentation temperatures to the 6568 °F (1820 °C) range for 2448 hours or so. However, there is never a discussion of how quickly to raise the temperature. If I have a lager at 50 °F(10 °C), do I raise the temperature only 23 degrees per day until I hit the range (adding ~7 days) to avoid shocking the yeast or do I raise it much faster to no ill-effect?
Seth Adams
Annapolis, Maryland
I have really never understood the idea of shocking yeast. Warming or chilling yeast within the temperature range that brewers ferment beer can and does occur quickly in commercial breweries without negatively affecting the yeast or the resultant beer. Fermenting too warm can of course lead to excessive production of esters, higher alcohols, sulfur, phenols, and other aromatic compounds, so controlling fermentation temperature is an important facet of brewing process control. The short answer to your question about the warming rate is not to worry about it. The easiest way to warm a batch of lager is to move your carboy from your lager fridge to a cool closet or corner in your basement and just let things happen.
