Effect of xanthan gum on the release of strawberry flavor in formulated soy beverage

Highlights

• The release of flavor compounds was restrained in SPI and/or xanthan gum solution.

• Xanthan gum evidently changed the retention of (Z)-3-hexen-1-ol, limonene and diacetyl.

• Other esters promoted flavor ester release in SPI-xanthan gum mixture solution.

• Less-volatiles accelerated ester release to some extent in different matrices.

Abstract

The effects of xanthan gum on the release of strawberry flavor compounds in formulated soy protein isolate (SPI) beverage were investigated by headspace gas chromatography (GC). Seven strawberry flavor compounds (limonene, ethyl hexanoate, (Z)-3-hexenyl acetate, ethyl 2-methylbutanoate, ethyl butanoate, (Z)-3-hexen-1-ol and diacetyl) could be detected by GC and hence analyzed the gas-matrix partition coefficients (K). The release of flavor compounds was restrained in SPI and/or xanthan gum solution. The retention of (Z)-3-hexen-1-ol, limonene and diacetyl significantly changed (p < 0.05) with increasing xanthan gum concentrations. Presence of any other esters led to suppression of the release of ester compounds in water and SPI solution. The less-volatiles (γ-decalactone, methyl cinnamate, hexanoic acid, 2-methyl butyric acid and furaneol) accelerated the release of ester compounds to some extent in different matrices. The above results demonstrated that presence of SPI and xanthan gum could bring about an imbalance in the strawberry flavor.

Introduction

Acceptability of foods by consumers mainly relies on their sensory attributes, among which flavor perception plays an important role. Flavor compounds can be naturally present in foods or can be added to balance. Thus, the perception may change both due to changes in volatility of the flavor compounds or a small modification of a food matrix, which consequently could affect the overall flavor profiles (Heilig, Cetin, Erpenbach, Hohn, & Hinrichs, 2011)

Soy proteins have become popular among consumers owing to their abundant supply, relatively low cost and nutritive value (Arora & Damodaran, 2010). However, the consumption of soy foods is still limited in mainstream food applications, due to the presence of undesirable beany or grassy off-flavors (Endo, Ohno, Tanji, Shimada, & Kaneko, 2005). Furthermore, flavor compounds added to a soy food product may interact with soy protein or other ingredients (Evageliou and Patsiakou, 2014, Moon and Li-Chan, 2007), resulting in an imbalance in the flavor profile. Hydrocolloids, which can modify the rate and intensity of flavor release through diffusion, caging in by gel effect, trapping in micro-regions, molecular interactions and molecular inclusion (Bylaite, Adler-Nissen, & Meyer, 2005), are among the most used additives in industrially manufactured beverage foods. Previous studies have shown the influence of hydrocolloids on the release of flavor compounds in different model systems. For instance, binding studies with acacia gum (Savary, Hucher, Petibon, & Grisel, 2014), gellan, pectin (Evageliou, Papastamopoulou, Frantzeskaki, & Christodoulidou, 2015) or gelatine (Zafeiropoulou, Evageliou, Gardeli, Yanniotis, & Komaitis, 2012) have been reported. Kühn, Delahunty, Considine, and Singh (2009) researched the influence of sodium carboxymethylcellulose (CMC) on the interaction between milk protein and 2-nonanone. The effect of hydrocolloids on flavor compounds in complex systems such as yoghurt or dairy were also studied (Decourcelle et al., 2004, Lubbers et al., 2007, Philippe et al., 2003). However, it is less clear how hydrocolloids influence the perception when present in a soy protein beverage.

On the other hand, most published papers to date have selected single volatile model compounds or homologous series of aldehydes, ketones or alcohols (Damodaran and Kinsella, 1980, Kühn et al., 2007, Wang and Arntfield, 2014). Despite the great amount of research dealing with the actual flavoring system (Boland et al., 2006, Decourcelle et al., 2004, Heilig et al., 2011, Martuscelli et al., 2008, Moon and Li-Chan, 2007, Vidrih et al., 2009), relatively limited studies have been performed on the interaction within non-homologues on the release of flavor compounds. For instance, Wang and Arntfield (2015) researched the competitive binding between heterological 2-hexanone and hexanal. Thus, numerous studies on the release of flavor compounds in model systems have been published, and they promoted the understanding of the interactions of flavor compounds with food ingredients. However, due to the lack of specific information about imbalance of flavor profile in a complicated flavoring system or real food system, the commercial value of these reports could be limited.

For an efficient adjustment or balance of flavor in processed foods or beverages with soy protein ingredients, it is important to understand not only how the individual food ingredients like soy proteins or xanthan gum interact with specific flavor compound in model systems, but also how various coexistence complex flavor compounds would affect flavor release in different food matrices. The aim of this study was to better understand the behavior of strawberry flavor compounds in model systems. The effect of xanthan gum addition on the interaction between strawberry flavor compounds and SPI was investigated. The simplified method, namely phase ratio variation (PRV) method, was used to explore the partition coefficients of the flavor compounds in different matrices. The results can pave the way for further research to elucidate strategies maximizing perception of strawberry flavor in soy beverage products.