Reduction of the glucose syrup browning rate by the use

Journal of Food Engineering 80 (2007) 370–373
www.elsevier.com/locate/jfoodeng
Reduction of the glucose syrup browning rate by the use
of modified atmosphere packaging
Ahmadreza Raisi a, Abdolreza Aroujalian
a
a,b,*
Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Ave., P.O.Box 15875-4413, Tehran, Iran
bFood ProcessingEngineering and Biotechnology Research Center, Amirkabir University of Technology (Tehran Polytechnic),
Hafez St., P.O.BOX 15875-4413, Tehran, Iran
Received 13 June 2004; received in revised form 19 April 2006; accepted 20 April 2006
Available online 1 August 2006
Abstract
Effects of modified atmosphere packaging (MAP) onbrowning in glucose syrups stored at 25 °C and 45 °C were studied. Different
atmosphere such as air, 100% N2, 90% N2/10% O2, 25% CO2/75% N2, 75% CO2/25% N2 and vacuum were examined. The glucose syrups
stored at 45 °C and pH 5 were completely brown after 26 weeks under vacuum packaging while they were brown after 15 weeks at that
temperature and pH 6 under air packaging system. No color formationwas observed in glucose syrups stored at 25 °C during this work.
As so glucose syrups kept under CO2 gas had no significant effect on browning.
Ó 2006 Elsevier Ltd. All rights reserved.
Keywords: Glucose syrups; Browning; Modified atmosphere packaging (MAP); Shelf life
1. Introduction
Shelf life is the duration of that period between the
packaging of a product and its use, for which thequality
of the product remains acceptable to the product user or
the shelf life refers to the time for which a food can remain
on both the retailer’s and consumer’s shelf before it
becomes unacceptable (Robertson, 1993). Product shelf
life can be controlled by three factors: (i) product charac-
teristics, (ii) the environment to which the product is
exposed during distribution, and (iii) theproperties of the
package.
The shelf life of a product can be altered by changing its
composition and form, the environment to which it is
exposed, or the packaging system (Harte & Gray, 1987).
In the case of glucose syrup, the major factor affecting the
shelf life is brown color formation. Maillard reactions are
the main causes of brown color formation in glucose syrup.
Non-enzymaticbrowning reactions between amino acids
*
Corresponding author. Tel.: +98 21 64543163; fax: +98 21 66405847.
E-mail address: aroujali@aut.ac.ir (A. Aroujalian).
and reducing sugars are the basis of the Maillard reactions.
This reaction in food is actually a complex network of chem-
ical reactions which usually takes place during food process-
ing or storage. Maillard reactions play anessential role in
food acceptance through the ways they influence quality
factors such as flavor, color, texture and nutritional value
(Rizzi, 1994). In glucose syrups, the formation of color
and odors determines the sensorial properties such as taste
and flavor and also provides an index of purity. Color for-
mation in glucose syrups during the manufacture of high
boiled candies can be seriousproblems for the confection-
ery industry as it may lead to the loss of acceptable color
and to the development of off-flavors (Kearsley & Brich,
1985).
Mechanism and kinetic of color formation and factors
affecting color development in glucose syrups during stor-
age such as time of storage, temperature, pH, dextrose
equivalent and sulfur dioxide, have been previously studied
(Ramchander &Feather, 1975; Kearsley, 1978; Sapers,
1993; Bostan & Boyacioglu, 1997). In this work, effects
modified atmosphere packaging (MAP) on the color for-
mation and shelf lives of glucose syrups were determined.
0260-8774/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved.
doi:10.1016/j.jfoodeng.2006.04.061

A. Raisi, A. Aroujalian / Journal of Food Engineering 80 (2007) 370–373
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