2009_Book_FoodChemistry

722 15 Cereals and Cereal Products
Table 15.47. The effect of α-amylase preparations on baking results
α-Amylase preparation
White bread
Origin Activity a Volume Crumb
(units) (ml)
pores
structure
Without addition 2400 average average
Wheat malt 140 2790 good good
560 3000 good good
1120 2860 average good
Aspergillus 140 2750 very good very good
oryzae 560 2900 good good
1120 2950 average average
Bacillus 7 2600 good good
subtilis 35 2600 good average
140 2640 poor very poor
a α-Amylase units in 700 g flour.
15.4.1.4.9 Milk and Soy Products
Dairy products such as skim milk, buttermilk,
whey and casein are added to flour in combination
with the ingredients or additives mentioned
so far. These dairy products are used in either
powdered or liquid form as well as either whole
or in the form of defatted powder. In such
cases, the proteins added to the dough increase
its water binding capacity and provide a juicy
crumb.
15.4.1.5 Influence of Additives on Baking
Properties of Rye Flour
Rye flour often requires an improved water binding
capacity. For this purpose, 2–4% of pregelatinized
flour is added. In addition, artificial acidification
of the rye dough is practiced; hence both
aspects will be covered.
15.4.1.5.1 Pregelatinized Flour
Pregelatinized flour is made from ground cereals
such as wheat, rye, rice, millet, etc. by cooking
and steaming in autoclaves followed by drying
and repeated milling. Such pregelatinized
flours are sometimes blended with guar flour or
alginates.
15.4.1.5.2 Acids
Rye flour is used in bread baking with sour dough
fermentation (cf. 15.4.2.2).
Artificial acidification can be achieved by the
addition of lactic, acetic, tartaric or citric acid to
rye dough or by adding acidic forms of sodium
and calcium salts of ortho- and/or pyrophosphoric
acids.
Other preparations for acidification, the so-called
dry or instant acids, consist of pregelatinized flour
blended with a sour dough concentrate or of cereal
mash prefermented by lactic bacteria. The
acid values (for definitions see 15.4.1.1.1) vary
from 100–1000.
15.4.1.6 Dough Leavening Agents
Dough consisting only of flour and water gives
a dense flat cake. Baked products with a porous
crumb, such as bread, are obtained only after the
dough is leavened. This is achieved for wheat
dough by addition of yeast while, for fine baked
products, baking powders are used. Rye dough