Anyone who has ever baked bread knows that it is highly susceptible to weather conditions. That's because a key ingredient, yeast, is a living organism that works better some days than others. Yeast is at its most active in a warm, humid environment, but paradoxically, that doesn't always guarantee the best bread. Overly active yeast results in unpleasantly fermented flavors and odors and can also impair the texture of the bread. High humidity can also affect the amount of water required in a recipe. Fortunately, there are several adjustments a skilled baker can make.
Reduce the amount of liquid in your bread recipe by 1/4 cup for multi-loaf batches or by 2 tbsp. in a single-loaf batch. Mix the dough as usual in your bowl, bread machine or stand mixer. Add more liquid as needed, until the correct consistency has been reached.
Cut back on the amount of yeast used in your recipe to compensate for too-rapid yeast growth. A standard package of yeast is 2-1/4 tsp., but on hot and humid days, a batch of dough may require as little as 1-1/2 tsp. The smaller amount of yeast will still leaven the bread but without generating fermented flavors and odors.
Add salt to your bread recipe. Salt inhibits the growth of yeast; as little as 20 percent extra in a bread dough will inhibit over-rising and fermentation.
Reduce the sugar in a recipe to slow yeast growth. Unless the recipe is for a sweet dough, there is probably enough naturally occurring sugar in the flour for the yeast to do its work. The sugar may be readily omitted from regular sandwich loaves during hot and humid weather.
Substitute bread flour if your recipe calls for all-purpose flour or does not specify. Bread flour is higher in gluten and absorbs slightly more liquid than all-purpose flour.
Use cold liquids rather than warm, especially if heat is a factor in combination with the humidity. This will slow the growth of the yeast and help inhibit over-rising.
You may find it necessary to combine two or more of these techniques if you live in an area where high humidity and heat are common.