Impact of proteins and polysaccharides on flavor release from oil-in-water emulsions during simulated cooking

Our objective was to establish the influence of biopolymer additives on the flavor release profiles of model food emulsions during simulated cooking. Allyl methyl disulfide (AMDS), a volatile hydrophobic flavor found in garlic, was used as a model aroma. This type of flavor compound is easily lost from foods during thermal processing and so there is a need to identify effective strategies to improve its retention and modulate its release profile. The impact of protein (sodium caseinate and whey protein) and polysaccharide (maltodextrin, xanthan gum, sodium alginate, corn starch, methyl cellulose, and beta-cyclodextrin) addition (0.5%) on the flavor retention profile of AMDS-loaded emulsions subjected to simulated cooking was determined. Corn oil was used as the oil phase to formulate the oil-in-water emulsions. Emulsions were heated from room temperature to boiling and then held for 30 min to establish the impact of biopolymer addition on their flavor retention profiles. The impact of biopolymer concentration on flavor retention was also studied using maltodextrin (0-40%) and xanthan gum (0-0.5%). The flavor retention profiles of the emulsions containing 0.5% maltodextrin, sodium alginate, whey protein, sodium caseinate, or corn starch, were the same as those as the control (no additives). Conversely, addition of 0.5% methyl cellulose, beta-cyclodextrin, or xanthan gum led to faster flavor release during cooking. The thermal stability of the emulsions appeared to be the dominant factor determining their flavor release: additives that promoted coalescence during heating led to faster flavor release. Moreover, addition of high levels of maltodextrin and xanthan gum promoted depletion flocculation, which also led to faster flavor release during heating. In contrast, there appeared to be no correlation between emulsion viscosity and the flavor release profile. These results are important for designing emulsion-based food products, such as sauces and soups, with controlled flavor release profiles during cooking.