Instant yeast or the smaller-grained "rapid-rise" yeast variety doesn't need to bloom, and can be added directly to the dry ingredients. It is always active and has a long shelf life. Some professional bakers think instant yeast and active dry yeast produces a worse flavor compared to fresh yeast, but others detect no difference in the end result.  Never use brewer's yeast, champagne yeast, or wine yeast for baking. Pour a small quantity of water or milk into a heat-safe container, writing down how much you use. The exact amount doesn't matter, but you should deduct this amount from the liquids in your recipe. 1/2 cup (120 mL) should be more than enough for a typical bread recipe. For instance, if you use 1/2 cup (120 mL) of water to bloom the yeast, and the recipe calls for 1 cup (240 mL) of water total, use 1/2 cup (120 mL) of water instead since you'll be mixing in the remaining 1/2 cup (120 mL) along with the yeast. Warm the liquid to 105-110ºF (40–43ºC), which is warm but not hot or steaming. While yeast functions best at slightly lower temperatures, active dry yeast takes a little extra heat to get started. If you don't own a food thermometer, warm the liquid to a lukewarm temperature, aiming low. A slightly cooler liquid will take longer to activate the yeast, but go too hot and the yeast will die and never activate at all. Only warm water is necessary to activate the yeast, but the sugar allows you to test whether the yeast is ready. Active yeast will eat the sugar and produce carbon dioxide and other substances, which is exactly the process that makes bread dough rise and gives it a unique flavor. Stir in the sugar rapidly until it dissolves. If you forget to add the sugar, you may add it after the yeast is already in the water. This is just as effective, but you should stir more gently to avoid spilling or damaging the yeast. Measure out however much yeast the recipe calls for and sprinkle it onto the liquid. If the recipe calls for fresh yeast, use 1/2 that amount of active dry yeast instead, since dry yeast is more concentrated. If the recipe calls for instant yeast, use 1.25 times that amount of active dry yeast instead. Note that some types of yeast expand when added to water. Transfer to a larger container if necessary to avoid spilling during this process. As the yeast sitting on the water's surface or slowly sinks, the water will dissolve the inactive yeast coating and free the active yeast in the center. After allowing time for this to happen, stir the yeast gently into the water. These is no need to time this step precisely. It is unlikely the yeast will be affected by the stirring, even if you stir it in immediately. If the yeast is alive and active, it will start consuming the sugar and releasing carbon dioxide, the gas that causes bread to rise. If the surface of the mixture becomes foamy or bubbly, the yeast is active and can be added to the other ingredients according to your recipe.  You may have to look closely for bubbles around the edge of the bowl. Other signs of activity may include a noticeable "yeasty" smell or an expanded volume, but these are not always noticeable. Unfortunately, if the mixture does not foam, the yeast is likely dead and cannot be used in recipes. You may wish to add some slightly warmed water, no hotter than 115ºF (43ºC), and let it sit an extra 10 minutes. If it has not foamed by this point, discard it. Add the liquid mixture containing the yeast when the recipe instructs you to add the yeast. Do not attempt to strain the yeast out.
اترك هذه العملية برمتها إذا كانت الخميرة فورية. قِس كمية صغيرة من الماء أو الحليب. دفّئ السائل. اخلط ملعقة صغيرة (5 مل) من السكر. رُشّ الخميرة على سطح السائل. قلّب الخميرة بعد 30 إلى 90 ثانية. انتظر 10 دقائق، وراقب خلال ذلك انتظارًا لظهور الفقاعات أو الزّبَد. أضف خليط الخميرة السائلة في المرحلة التي تملي الوصفة استعمالها بها.