2009_Book_FoodChemistry

15.4 Baked Products 711
an extremely low odor threshold and is formed
from linolenic acid.
15.3.2.2.3 Barley
Removal of hull (fruit and seed coatings) yields
groats which, after grinding, provide marketable
products of large or fine particle size.
ered. Flour improvers and dough leavening agents
will be emphasized.
Characterization of the raw materials and additives
is, in practice, made by assessing the dough
rheological properties and by baking tests. Basic
research endeavors to understand the nature
of flour constituents and the reactions which affect
their behavior in dough handling and baking.
15.4 Baked Products
Baked products (for a review, see Table 15.39) are
made from milled wheat, rye and, to a lesser extent,
other cereals by the addition of water, salt,
a leavening agent and other ingredients (shortening,
milk, sugar, eggs, etc.). The following operations
are involved:
• Selection and preparation of the raw materials
• Dough making and handling
• Baking
• Measures for quality preservation
15.4.1 Raw Materials
Among the ingredients involved in a formulation,
only flour and those additives which affect dough
rheological and/or baking properties will be cov-
Table 15.39. Classification of baked products
Bread including Made entirely or mostly from
small baked prod- cereal flours; moisture content on
ucts (rolls, buns) average 15%.
Addition of sugar, milk and/or
shortenings amounts to less than
10%. Small baked products differ
from bread only by their size,
form and weight.
Fine baked goods, Made of cereal flours with at least
including long term 10% shortening and/or sugar, as
or extended shelf well as other added ingredients.
life products such In baked goods for long shelf life
as biscuits, crack- the moisture content is greatly
ers, cookies etc. reduced.
15.4.1.1 Wheat Flour
A flour of optimal baking properties is required
and chosen to match the quality of the desired
product (cf. Table 15.35). The baking quality of
wheat is strongly influenced by the cultivar (cf.
Table 15.41) and also by conditions of growth and
cultivation (climate, location), and subsequently
by flour storage conditions and duration. Prior
quality control is of importance to assess the overall
baking quality of wheat flour. Flour particle
size and color are assessed by sensory analysis.
Graspable flours (cf. 15.3.1.3) are made from
hard gluten-rich cultivars. Water uptake is slow
when compared to smooth flour, and they make
dry doughs.
The color difference is important, and is assessed
with a wetted flour sample on a black background
(Pekar-test).
15.4.1.1.1 Chemical Assays
Flour acidity (ml of 0.1mol/l NaOH/10 g,
titrated in the presence of phenolphthalein)
depends upon the extraction rate of the flour and
ranges between 2.0ml/g (flour type 450) and
5.5ml/g (flour type 1800). Too low acidity often
reflects poorly aged flour. Acidity above 7.0
suggests microbial spoilage.
The gluten content, which is the residue left after
the dough is washed (10 g flour kneaded into
a dough with 6 ml of 2% NaCl, then washed
with tap water), provides an indication of flour
quality. A very low gluten content (<20%)
frequently results in dough deterioration when
machine-handled and also in baking faults.
A higher content of gluten will not guarantee
good baking quality (see “Maris Huntsman”