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In baking, a farinograph measures specific properties of flour. It was first developed and launched in 1928. The farinograph is a tool used for measuring the shear and viscosity of a mixture of flour and water. The primary units of the farinograph are Brabender Units, an arbitrary unit of measuring the viscosity of a fluid.〔(Starch in food: structure, function and applications )〕 The farinograph is a variation of the Brabender Plastograph that has been specialized for the baking industry, and it is used around the world for the objective measurement of a variety of flours. A baker can formulate end products by using the farinograph's results to determine the following: *Water absorption *Dough viscosity, including peak water to gluten ratio prior to gluten breakdown *Peak mixing time to arrive at desired water/gluten ratio *The stability of flour under mixing *The tolerance of a flour's gluten ==Method== The farinograph is drawn on a curved graph with the vertical axis labeled in Brabender Units (BU) and the horizontal axis labeled as time in minutes. The graph is generally hockey-stick shaped, with the curve being more or less acute depending on the strength of the gluten in the flour. The points of interest on the graph are fivefold: #Arrival Time (Absorption) - Absorption is the point chosen by the baking industry which represents a target water to flour ratio in bread. This ratio is marked at the 500 BU line and is taken as a rule of thumb for desired taste, texture, and dough performance during proofing and baking. All other measurements are based on this 500 BU standard. (For comparison, the accepted BU is 1000 or greater for noodles).〔(About PNW Regional Quality Data )〕 Thus on the graph above, Arrival time is the point on the graph where the top of the curve reaches the 500 BU point and indicates the rate of absorption (minutes/BU). #Peak time - Peak time is reached at the highest point on the curve, and indicates when the dough has reached is maximum viscosity before gluten strands begin to break down. #Mixing Tolerance Index (MTI) - MTI is found by taking the difference in BU between the peak time point (on the graph above 3 minutes, 30 seconds) and 5 minutes after peak time is reached. This is used by bakers to determine the amount that a dough will soften over a period of mixing. MTI may be expressed as a value in BU or as a percentage of BU lost over time (). #Departure Time - Departure time is defined as the point at which the top of the curve goes below the 500 BU line. This point is generally considered the point at which gluten is breaking down and dough has become over mixed. #Stability - Stability is the point between arrival time and departure time and generally indicates the strength of a flour (how much gluten a flour has and how strong it is). 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「farinograph」の詳細全文を読む スポンサード リンク
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