Sensory profile of hemicellulose-rich wood extracts in yogurt models

Wood is an abundant and sustainable source of emerging food ingredients, namely hemicelluloses that fulfil a number of requirements for functional hydrocolloids. Hemicelluloses, especially spruce galactoglucomannans (GGM) and birch glucuronoxylans (GX), have potential to be used as stabilizers in various foods such as yogurts, beverages, dressings, and desserts. However, in addition to good technological functionality, safety, and low price, the applicability and market potential of new hydrocolloids is determined by their sensory properties. The present study reports, for the first time, the sensory profile of spruce GGM and birch GX in food. Sensory profiles from generic descriptive analysis of GGM- and GX-rich extracts, processed by spray drying or ethanol precipitation, were compared in three types of model food systems: water solutions, yogurt with solutions, and yogurt with emulsions stabilized by GGM or GX. Gum Arabic was included for comparison with a commercial ingredient known to have a mild flavor. The results showed that GGM and GX have a woody flavor, which can be reduced by ethanol precipitation and, in yogurt, masked by other food ingredients.