Download Best Bread Production By eyebreadprojects Pdf book free online – from Best Bread Production By eyebreadprojects Pdf book; Cereal α-amylase is naturally present in flour.
It breaks the starch into simple sugars to feed the young plant. Levels will vary depending on the quality of the wheat and the weather conditions during harvest. Cereal α -amylase can be a beneficial bread improver, but at high levels can cause stickiness, most noticeably in sandwich breads; the levels are measured in seconds using Hagberg Falling Number (HFN), where 60s is a very high level and 450s is a very
low level. Flour millers control the level in flour by blending the wheats.
The term alpha-amylase is used to describe a range of enzymes, which are capable of breaking down damaged starch granules into materials known as dextrins and in combination with beta-amylase they will produce maltose. Alpha and beta-amylase work in combination. Beta-amylase attacks the ends of the amylose and amylopectin chains breaking off individual maltose sugar molecules. Most wheat flours contain adequate levels of beta-amylase so it is the alpha-amylase that controls the reaction. Additions of alpha-amylase to doughs via improvers and even in flour mills are preferred in the fungal rather that the cereal form.
This is because the fungal form is inactivated at lower temperatures in the baking process and reduces the risk of the formation of high levels of sticky dextrins. Excess cereal α- amylase reduces bread quality. Cereal alpha-amylase is produced during the growing cycle and can achieve quite high levels if the period around harvesting is wet. The dextrins which are produced by the action of alpha-amylase on damaged starch are sticky and if their level is high enough in the finished bread they build up on the slicer blades and can reduce their efficiency to such an extent that loaves will collapse.