Food Chemistry

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.

15.4 Baked Products

Baked products (for a review, see Table 15.39) are
made from milled wheat, rye and, to a lesser ex-
tent, other cereals by the addition of water, salt,
a leavening agent and other ingredients (shorten-
ing, milk, sugar, eggs, etc.). The following opera-
tions 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.

ered. Flour improvers and dough leavening agents

will be emphasized.

Characterization of the raw materials and addi-

tives is, in practice, made by assessing the dough

rheological properties and by baking tests. Ba-

sic research endeavors to understand the nature

of flour constituents and the reactions which af-

fect their behavior in dough handling and baking.

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 over-

all baking quality of wheat flour. Flour particle

size and color are assessed by sensory analy-

sis. 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/lNaOH/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.

Thegluten 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”