Food Biochemistry and Food Processing (2 edition)

BLBS102-c30 BLBS102-Simpson March 21, 2012 13:56 Trim: 276mm X 219mm Printer Name: Yet to Come

590 Part 5: Fruits, Vegetables, and Cereals

pilot-scale under controlled formulation and processing

conditions.

Sadd et al. (2008) studied different alternative mitigation

strategies to reduce acrylamide in bakery products. Whereas

yeast fermentation was an effective way of reducing asparagine

and hence acrylamide, amino acid addition to dough gave mod-

est reduction of this contaminant. Removing ammonium-based

raising agents was also beneficial. Calcium supplementation for

binding asparagine looked promising, but interactions with other

ingredients need further investigation. Lowering the dough pH

reduced acrylamide, but at the expense of higher levels of other

process contaminants.

Alternatively, Anese et al. (2010) have recently evaluated the

possibility to remove acrylamide from previously hydrated com-

mercial biscuits by vacuum treatment. Selection of suitable tem-

perature, time and pressure conditions has proved to be required

to maximise acrylamide removal while minimising its formation

and effect on the sensory properties.

On the other hand, the correlation between mitigation of acry-

lamide and its influence on beneficial properties of food, such as

the antioxidant activity has been scarcely studied. Summa et al.

(2006) reported a strong link between the composition of the

pastries and baking parameters and the genesis of acrylamide as

well as antioxidants. Therefore, suppressing the MR generally

leads not only to acrylamide mitigation but also to losses of

substances considered to be beneficial.

Maltulose

Besides MR, isomerisation of reducing carbohydrates may take

place during processing of cookies, crackers and breakfast cere-

als. Maltulose (Fig. 30.2), an epimerisation product of maltose,

has been found in the crust of bread (Westerlund et al. 1989).

Maltulose formation has also been observed during the heating

of a maltodextrin solution at high temperature (180◦C) (Kroh

et al. 1996). Garc ́ıa-Banos et al. (2000, 2002) detected mal- ̃

tulose in commercial enteral products and proposed the ratio

maltose:maltulose as a heat treatment and storage indicator of

enteral formulas.

In cookies, crackers and breakfast cereals, Rada-Mendoza

et al. (2004) detected maltulose (from traces to 842 mg/100 g)

in all commercial samples analysed. Figure 30.3 shows the gas

chromatographic profile of the trimethylsilyl oxime-derivatives

of mono- and disaccharide fractions of a cookie sample. Sim-

ilar patterns were obtained for crackers and breakfast cereals.

The formation of maltulose depends mainly on initial maltose

500

400

300

200

100

0

10

1

2

3 6

4

5

7

8

9

10

1112

13

14

Time (min)

Absorbance

20 30 40 50

Figure 30.3.Gas chromatographic profile of the trimethylsilyl oxime-derivatives of fructose (1,2), glucose (3,4), sucrose (6), lactulose (8),

lactose (9, 10), maltulose (11, 12) and maltose (13,14) of a cookie sample. Peaks 5 and 7 were the internal standards:myo-inositol and

trehalose, respectively (from Rada-Mendoza et al. 2004).