Review on correlations between depression and nutritional status of elderly patients

International audienceAmong mental health diseases, depression is a global problem with a high prevalence for elderly patients and is directly related to the nutritional status. Depression of older people is considered as a psychological phenomenon with consequences for nutrition, additionally nutrition disorder can conduce to psychological effects. Scientists have identified essential nutritional factors, which can lead in case of deficiency to depression. Among these nutritional factors, some water-soluble and fat-soluble vitamins, minerals, polyunsaturated fatty acids, polyphenols, as well as proteins were identified. This review highlights the relationship between balanced diets in elderly people and the risk of depression

Microbial β C-S Lyases: Enzymes with Multifaceted Roles in Flavor Generation

International audienceβ C-S lyases (β-CSLs; EC 4.4.1.8) are enzymes catalyzing the dissociation of β carbon–sulfur bonds of cysteine S-conjugates to produce odorant metabolites with a free thiol group. These enzymes are increasingly studied for their role in flavor generation in a variety of food products, whether these processes occur directly in plants, by microbial β-CSLs during fermentation, or in the mouth under the action of the oral microbiota. Microbial β-CSLs react with sulfur aroma precursors present in beverages, vegetables, fruits, or aromatic herbs like hop but also potentially with some precursors formed through Maillard reactions in cooked foods such as meat or coffee. β-CSLs from microorganisms like yeasts and lactic acid bacteria have been studied for their role in the release of polyfunctional thiols in wine and beer during fermentation. In addition, β-CSLs from microorganisms of the human oral cavity were shown to metabolize similar precursors and to produce aroma in the mouth with an impact on retro-olfaction. This review summarizes the current knowledge on β-CSLs involved in flavor generation with a focus on enzymes from microbial species present either in the fermentative processes or in the oral cavity. This paper highlights the importance of this enzyme family in the food continuum, from production to consumption, and offers new perspectives concerning the utilization of β-CSLs as a flavor enhancer

Unlocking Flavor Potential Using Microbial β-Glucosidases in Food Processing

International audienceAroma is among of the most important criteria that indicate the quality of food and beverage products. Aroma compounds can be found as free molecules or glycosides. Notably, a significant portion of aroma precursors accumulates in numerous food products as nonvolatile and flavorless glycoconjugates, termed glycosidic aroma precursors. When subjected to enzymatic hydrolysis, these seemingly inert, nonvolatile glycosides undergo transformation into fragrant volatiles or volatiles that can generate odor-active compounds during food processing. In this context, microbial β-glucosidases play a pivotal role in enhancing or compromising the development of flavors during food and beverage processing. β-glucosidases derived from bacteria and yeast can be utilized to modulate the concentration of particular aroma and taste compounds, such as bitterness, which can be decreased through hydrolysis by glycosidases. Furthermore, oral microbiota can influence flavor perception by releasing volatile compounds that can enhance or alter the perception of food products. In this review, considering the glycosidic flavor precursors present in diverse food and beverage products, we underscore the significance of glycosidases with various origins. Subsequently, we delve into emerging insights regarding the release of aroma within the human oral cavity due to the activity of oral microbial glycosidases

Non-Fat Yogurt Fortified with Whey Protein Isolate: Physicochemical, Rheological, and Microstructural Properties

The demand for low- and non-fat products has recently increased due to the health problems, such as obesity, diabetes, and cardiovascular diseases, that have resulted from high-fat products. However, the reduction in fat can affect the quality of products adversely. The objective of this work was to explore the potential of whey protein isolate (WPI) in improving the quality of non-fat yogurt prepared using skim milk powder (SMP). Yogurt mixes (standardized at 14% total solids) were formulated using SMP as a milk base enriched with WPI. The SMP was replaced by WPI in the yogurt mixes at a rate of 3, 5, 7, and 9%. Full-fat and non-fat set-style yogurts were prepared from whole milk and skim milk, respectively, as controls. Yogurts were fermented at 43 °C to get a pH of 4.6 and stored at 4 °C for the next day. The texture, microstructure, rheological characteristics, and sensory properties of the yogurt samples were studied. The incorporation of WPI increased the water holding capacity to 50% as compared to the non-fat control. This improved the rheological properties while the yogurt viscosity increased in direct proportion with increasing the WPI. The firmness of yogurt was inversely proportional to the increase in WPI, which resulted in 180 g firmness when 9% WPI was added to the non-fat yogurt formulations. Yogurts’ microstructure improved by the addition of WPI. The non-fat yogurt incorporated with 3 and 7% WPI had comparable sensory and textural characteristics to the full-fat yogurt. WPI can be used as a fat replacer to develop low-fat yogurt with desired features. WPI may be a natural and economical ingredient for producing low- and non-fat fermented dairy food products

The role of perireceptor events in flavor perception

International audienceThe sensory perception of food is a complex phenomenon involving the integration of different stimuli (aroma, taste, trigeminal sensations, texture and visual). Flavor compounds activate odorant, taste and trigeminal chemoreceptors, generating a depolarization of the sensory neurons and then the consciousness of food flavor perception. Recent studies are increasingly highlighting the importance of perireceptor events, which include all the molecular events surrounding the receptors, in the modulation of flavor perception. These events affect the quantity and quality of flavor compounds in the environment of chemoreceptors. They include the metabolization of flavor compounds by enzymes present in biological fluids (saliva and mucus) and the oronasal epithelia and noncovalent interactions with binding proteins. Perireceptor mechanisms have been extensively studied in insects and mammals, demonstrating the importance of the entailed processes in the termination of the chemical signal. In humans, research is in full swing. Here, we reviewed the perireceptor mechanisms recently reported in vitro , in biological fluids and in cells and in vivo in humans. These studies indicate that perireceptor mechanisms likely have an important contribution to flavor perception. This mini-review focuses on recent pioneering studies that are paving the way for this new research area. It also suggests that new approaches taking into account the real conditions of food consumption will be required in the future to accurately address this question