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Proofing (also called proving or more rarely blooming), as the term is used by bakers, is the final rise of shaped bread dough before baking. It refers to a specific rest period within the more generalized process known as ''fermentation''. Fermentation is a step in creating yeast breads and baked goods where the yeast is allowed to leaven the dough.〔(Proofing ), About.com〕 Fermentation rest periods are not always explicitly named, and can appear in recipes as "Allow dough to rise." When they are named, terms include "bulk fermentation," "first rise," "second rise," "final proof" and "shaped proof". Proofing yeast (as opposed to proofing the shaped bread dough) refers to the process of first dissolving yeast in warm water, a needed hydration step when using active dry yeast.〔Instant dry yeast may be placed directly into flour undissolved.〕 Proofing can also refer to testing the viability of yeast by dissolving it in water and feeding it sugar or carbohydrate.〔 If the yeast is viable, it will feed on the sugar and produce a visible layer of bubbles on the surface of the water mixture. ==Dough processes== The process of making yeast-leavened bread involves a series of alternating work and rest periods. Work periods occur when the dough is manipulated by the baker. Some work periods are called ''mixing'', ''kneading'', and ''folding'', as well as ''division'', ''shaping'', and ''panning''. Work periods are typically followed by rest periods, these occur when dough is allowed to sit undisturbed. Particular rest periods include, but are not limited to, ''autolyse'', ''bulk fermentation'' and ''proofing''. ''Proofing'', also sometimes called ''final fermentation'', is the specific term for allowing dough to rise after it has been shaped and before it is baked. Some breads begin mixing with an ''Autolyse''. This refers to a period of rest after the initial mixing of flour and water, a rest period that occurs sequentially before the addition of yeast, salt and other ingredients. This rest period allows for better absorption of water and helps the gluten and starches to align. The autolyse is credited to Raymond Calvel, who recommended it as a way to reduce kneading time and thereby improve the flavor and color of bread. ''Proofing the yeast'' is a hydration or dissolving process that occurs when dry yeast is mixed with warm water and allowed to rest for a short time. The minimum weight of water required may be calculated: .〔 Yeast viability can be tested by mixing yeast in warm water and sugar, and following a short rest period during which it first dissolves then begins to grow, a layer of foam is developed by the action of the yeast, a sign of primary fermentation and live yeast. Typically, using US customary volume units, ¼ cup (≈ 59.1 mL) water at and ½ teaspoon (≈ 2.5 mL) of sugar are used, or expressed differently, a sugar weight of about 3.5% of the water's weight. While this sugar may be sucrose or table sugar, instead it may be glucose or maltose.〔 ''Fermentation'' typically begins when viable baker's yeast or a starter culture is added to flour and water. Enzymes in the flour and yeast create sugars, which are consumed by the yeast, who in turn produce carbon dioxide and alcohol. Specifically, the grain enzyme diastase begins to convert starch in the grain to maltose. The baker's yeast enzyme maltase converts maltose into glucose, invertase converts any added sucrose to glucose and fructose, and zymase converts glucose and fructose to carbon dioxide gas which makes the dough rise, and alcohol which gives the baked bread flavor. Sourdough starters also produce lactic and acetic acids, further contributing to flavor. When the yeast cells die, they release high quantities of a protease which snip protein strands, and in large dieoffs result in soft, sticky dough, less baked volume and a coarse crumb,〔 but in smaller dieoffs, increase dough extensibility and baked volume. Different bread varieties will have different process requirements. These are generally classified as either straight or sponge dough processes. Straight doughs will require only a single mixing period.〔 During bulk fermentation straight-dough recipes may instruct a baker to "punch down" or "deflate" the dough, while artisan bakers will use terms like "stretching," "folding," and "degassing," meaning to expel gas from the carbon dioxide bubbles that have formed. Sponge doughs will need multiple mixing periods. ''Overproofing'' occurs when a fermenting dough has rested too long. Its bubbles have grown so large that they have popped and tunneled, and dough baked at this point would result in a bread with poor structure. Length of rest periods, including proofing, can be determined by time at specific temperatures or by characteristics. Often the "poke method" is used to determine if a dough has risen long enough. If the dough, when poked, springs back immediately it is ''underproofed'' and needs more time. Some breads are considered fully proofed if the indent left by the poke springs back slowly, while others are considered fully proofed when the indent remains and does not spring back. A bread that is properly proofed will balance gas production with the ability of the bread's gluten structure to contain it, and will exhibit good oven spring when baked. A bread that is under- or overproofed will have less oven spring and be more dense. An overproofed bread may even collapse in the oven as the volume of gas produced by the yeast can no longer be contained by the gluten structure. ''Retarding'' may occur at any time during fermentation and is accomplished by placing the dough into a dough retarder, refrigerator, or other cold environment to slow the activity of the yeast. The retarding stage is often used in sourdough bread recipes to allow the bread to develop its characteristic flavor. A cold fermentation stage is sometimes used to develop flavor in other artisan breads, with a part of the dough ("pre-ferment") before the final mixing, with the entire dough during bulk fermentation, or in the final fermentation stages after shaping. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Proofing (baking technique)」の詳細全文を読む スポンサード リンク
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