EFFECT OF TOMATO POMACE POWDER ON THE PHYSICOCHEMICAL PROPERTIES OF FLAT BREAD (BARBARI BREAD) MAHSA MAJZOOBI 1 , FARNAZ SARIRI GHAVI, ASGAR FARAHNAKY, JALAL JAMALIAN and GHOLAMREZA MESBAHI Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, Iran 1 Corresponding author. TEL: +98-711-613-8356; FAX: +98-711-6289017; EMAIL: majzoobi@shirazu.ac.ir Accepted for Publication May 14, 2009 doi:10.1111/j.1745-4549.2009.00447.x ABSTRACT Some hydrocolloids have been used to improve the quality of dough and bread. Tomato pomace is a good and cheap source of hydrocolloids and lysine (the limiting amino acid in cereals); hence, it has the potential to be used in bread making. In this study, tomato pomace powder was added to flat bread (Barbari bread) recipe at five levels of 0, 1, 3, 5 and 7% (w/w flour basis). Consequently, the following changes were observed: increase in dough water absorption, reduction in dough arrival, develop- ment and stability times and increase in dough softening after 5 and 12 min. The breads had higher moisture content, softer texture and delayed staling when stored for 24–96 h at 25C. However, when tomato pomace powder was used >5%, the color and taste of bread were affected adversely. Such effects were improved when tomato pomace powder was bleached with H2O2. PRACTICAL APPLICATIONS This research would have potential applications to the bakery industry in order to improve the quality of bread and to delay staling. It also introduces new application for tomato pomace, as a by-product of tomato paste and juice factories to be used as a bread improver and an anti-staling agent. INTRODUCTION Bread is the main source of energy for humans in many parts of the world, especially in poor countries where providing other sources of energy is expensive or impossible (Qarooni 1996; Quail 2004). Therefore, producing breads of high quality is of great importance. Fresh bread is palatable and can be recognized by its sensory attributes; however, in a few days after baking, crumb firmness increases significantly, crispness of bread crust decreases and bread loses its fragrance. These changes, regarded as bread staling, can cause a large economic damage to the bread- making industry (D’Appolonia and Morand 1981; Zobel and Kulp 1996; Schiraldi and Fessas 2001). Therefore, finding a method to increase bread shelf life is of great importance. Among the different factors affecting bread staling is the bread composition. Accordingly, modified dough recipes have been tried using proteins, hydrocolloids, fats, etc. The resulting bread had higher volume, softer texture, improved sensory attributes and delayed staling (D’Appolonia and Morand 1981; Roger et al. 1988; Amero and Collar 1996; Davidou et al. 1996; Rosell et al. 2001; Schiraldi and Fessas 2001; Guarda et al. 2004; Shalini and Laxmi 2007). Some hydrocolloids, such as cellulose derivatives and resis- tant starches, are known as dietary fibers or slowly digested starch which can have positive effects on the human digestive system and hence increase general health (Anderson 1991; Wang et al. 2005; John and Thomas 2008). Hydrocolloids are abundant in plants tissues, especially their skins and seed (Schieber et al. 2001; Del Valle et al. 2006). These parts are generally the wastes of vegetable- and fruit-processing factories which are used widely in animal feed as soil fertilizers and for extraction of food colorants (Schieber et al. 2001). However, they also can be considered as sources of hydrocolloids and therefore find new applications in the food industry. Journal of Food Processing and Preservation ISSN 1745-4549 247 Journal of Food Processing and Preservation 35 (2011) 247–256 © 2010 Wiley Periodicals, Inc.