Kinetic study of high-intensity ultrasound-assisted Maillard reaction in a model system of d-glucose and glycine.

A kinetic model for a high-intensity ultrasound-assisted Maillard reaction model system of d-glucose and glycine was proposed; activation energy (Ea) for each reaction step was calculated. Results showed that the generation of dicarbonyl compounds was significantly promoted by high-intensity ultrasound (e.g.

Effects of high-intensity ultrasound and oil type on the Maillard reaction of d-glucose and glycine in oil-in-water systems.

This study addresses the effect of high-intensity ultrasonic processing on four oil-in-water systems, using sunflower, peanut, olive and flaxseed oils, respectively, that contained an aqueous d-glucose and glycine Maillard reaction (MR) model system. The MR in the water phase was promoted as observed from higher depletion of reactants and higher amount of MR products (MRPs). A significantly higher amount of pyrazines was generated after ultrasonic processing, particularly in the sunflower and olive oil systems.

Effects of high-intensity ultrasound on Maillard reaction in a model system of d-xylose and l-lysine.

This study compared the effects of high-intensity ultrasound on Maillard reaction (MR) with those of thermally produced MR using a model system of d-xylose and l-lysine. The ultrasonic MR process had higher depletion rates of reactants and higher generation rates of intermediate MR products (MRPs) and melanoidins under relatively low processing temperatures (55 and 60°C). However, the rates were lower for ultrasonic MR than thermal MR when the processing temperature increased to 65, 70 and 75°C.

Odor-Specific Loss of Smell Sensitivity with Age as Revealed by the Specific Sensitivity Test.

The perception of odor mixtures plays an important role in human food intake, behavior, and emotions. Decline of smell acuity with normal aging could impact food perception and preferences at various ages. However, since the landmark Smell Survey by National Geographic, little has been elucidated on differences in the onset and extent of loss in olfactory sensitivity toward single odorants.

High-intensity ultrasound production of Maillard reaction flavor compounds in a cysteine-xylose model system.

Application of high intensity ultrasound has shown potential in the production of Maillard reaction odor-active flavor compounds in model systems. The impact of initial pH, sonication duration, and ultrasound intensity on the production of Maillard reaction products (MRPs) by ultrasound processing in a cysteine-xylose model system were evaluated using Response Surface Methodology (RSM) with a modified mathematical model. Generation of selected MRPs, 2-methylthiophene and tetramethyl pyrazine, was optimal at an initial pH of 6.

Plant essential oils as active antimicrobial agents.

Essential oils derived from plants have been recognized for decades to exhibit biological activities, including antioxidant, anticancer, and antimicrobial attributes. Antimicrobial activities of these natural plant materials have been intensively explored in recent years, mainly in response to the overwhelming concern of consumers over the safety of synthetic food additives. Gram-negative organisms are believed to be slightly less sensitive to essential oils than Gram-positive bacteria.

Volatile sulphur compounds and pathways of L-methionine catabolism in Williopsis yeasts.

Volatile sulphur compounds (VSCs) are important to the food industry due to their high potency and presence in many foods. This study assessed for the first time VSC production and pathways of L: -methionine catabolism in yeasts from the genus Williopsis with a view to understanding VSC formation and their potential flavour impact. Five strains of Williopsis saturnus (var.

Production of flavour-active methionol from methionine metabolism by yeasts in coconut cream.

Yeasts Candida kefyr NCYC143, Candida utilis CUM, Kluyveromyces lactis KL71, Saccharomyces bayanus SB1, Saccharomyces cerevisiae EC1118, Saccharomyces chevalieri CCICC1028, Candida famata (previously Torulopsis candida) CCICC1041 and Williopsis saturnus var. saturnus CBS254 were screened for their ability to produce flavour-active methionol (3-methylthio-1-propanol) in coconut cream supplemented with l-methionine. The yeasts varied with their ability to produce methionol from methionine with Saccharomyces cerevisiae EC1118 producing the most, followed by Kluyveromyces lactis KL71.