Increased plasma trimethylamine-N-oxide levels are associated with mild cognitive impairment in high cardiovascular risk elderly population.

Trimethylamine-N-oxide (TMAO) has been shown to be associated with cardiovascular (CV) disease and cognitive impairment. The association between early stages of cognitive impairment and TMAO in a high CV risk population has not been previously investigated. This study aimed to investigate the association between the plasma TMAO level and cognitive function in a population with a high risk of CV disease. Participants at a high risk of CV were included. The cognition was evaluated using the Montreal Cognitive Assessment. A score lower than 25 out of 30 was used to indicate mild cognitive impairment (MCI). Blood samples of all participants (n = 233) were collected to measure the plasma levels of TMAO and other metabolic parameters, including fasting blood sugar and lipid profiles. Logistic regression was used to evaluate the association between MCI and high plasma TMAO levels, adjusted for confounding factors. Of 233 patients, the mean age of patients in this study was 64 years old (SD 8.4). The median TMAO level was 4.31 µM (IQR 3.95). The high TMAO level was an independent risk factor of MCI (aOR 2.36, 95% CI 1.02 to 5.47; p 0.046), when adjusted for age, gender, health care service scheme, smoking history, metabolic syndrome, and history of established CV events. The high TMAO level was associated with MCI, after adjustment for potential confounding factors. These findings demonstrate that plasma TMAO levels can serve for target prediction as an independent risk factor for MCI in this population.

Comparative evaluation of acrylamide and polycyclic aromatic hydrocarbons contents in Robusta coffee beans roasted by hot air and superheated steam.

Although hot air (HA) is a conventional roasting medium for coffee beans, HA roasting is known to result in possible formation of toxic compounds, including acrolein, acrylamide and polycyclic aromatic hydrocarbons (PAHs). Superheated steam (SHS) roasting is therefore proposed as an alternative means to alleviate the formation of these toxic compounds in roasted coffee beans. Robusta coffee beans were roasted either with HA or SHS in a fluidized bed roaster at 210-250 °C until the bean color reached the targeted roast levels. The contents of acrolein, acrylamide and 16 PAHs in the roasted beans were determined; only acrylamide and 5 PAHs were nevertheless found. SHS roasting interestingly resulted in lower acrylamide contents in dark-roasted beans; similar trend was noted in the beans medium-roasted at 250 °C. The contents of three-ring PAHs, namely fluorene, phenanthrene and anthracene, in dark-roasted beans were significantly lower upon SHS roasting at 250 °C.

Roasting Kinetics and Chemical Composition Changes of Robusta Coffee Beans During Hot Air and Superheated Steam Roasting.

As it is known that Robusta coffee beans exhibit more bitterness, less acidity, and lacks sweetness with unbalance flavor as compared to their Arabica counterpart, a means to improve the quality of Robusta coffee beans is desirable. As a step that contributes to the coffee quality, it is interesting to determine if an alternative roasting technique could lead to the desired improved quality. Here, roasting kinetics and changes in pH and composition of Robusta coffee beans undergoing hot air and superheated steam (SHS) roasting at 190 to 250 °C were investigated. SHS roasting led to higher rates of bed temperature increase, moisture loss and decrease in lightness (L* value) of the beans. Evolutions of the moisture content and L* value of the beans could be well described by the adopted kinetic equations. pH, caffeine, sugars, and organic acids contents of the beans were significantly affected by the temperature and degree of roasting. Interestingly, beans roasted in SHS had lower pH, higher sucrose, glucose, and arabinose contents. Their fructose and acetic acid contents were nevertheless lower, indicating that the beans probably exhibited higher sweetness and citrus-like acidity, but lower unfavorable vinegar-like acidity. PRACTICAL APPLICATION: This study illustrates the possibility to improve the quality of Robusta coffee beans via a physical process. Use of superheated steam roasting at appropriate condition can enhance some desirable characters of Robusta beans; such beans indeed exhibit more resemblance to the more sought-after Arabica beans. This should be of much value to a roasting house and blender in such a way that a higher proportion of Robusta beans can be used in a commercial blend of coffee beans.

Influences of Superheated Steam Roasting and Water Activity Control as Oxidation Mitigation Methods on Physicochemical Properties, Lipid Oxidation, and Free Fatty Acids Compositions of Roasted Rice.

The feasibility of using superheated steam roasting and wetting to control the water activity in an optimal range to mitigate oxidation of roasted rice was evaluated. Changes in the bed temperature as well as rice kernel moisture content, water activity, and color were monitored during fluidized bed roasting with superheated steam and hot air at 170, 190, and 210 °C. Air-roasted rice was rewetted to raise its water activity to 0.30 to 0.35. All the samples were analyzed for the total oil content, peroxide value (PV), thiobarbituric acid (TBA) value, and free fatty acids (FFA) content and compositions. Higher roasting temperatures, especially at 210 °C, led to a significant increase (P ≤ 0.05) in the total oil content of the roasted rice. Wetting led to a significant (P ≤ 0.05) decrease in the TBA value of the air-roasted rice, although the total FFA content significantly (P ≤ 0.05) increased. Rice roasted in superheated steam at 210 °C exhibited significantly (P ≤ 0.05) lower PV and TBA value; their total FFA content also tended to decrease, which is desirable for a longer shelf life.

Electrodialytic removal of nitrate from pineapple juice: effect on selected physicochemical properties, amino acids, and aroma components of the juice.

This study aimed at investigating the effect of nitrate removal from pineapple juice by electrodialysis (ED) on selected properties of the ED-treated juice. Single-strength pineapple juice with reduced pulp content was treated by ED to reduce the nitrate concentration to 15, 10, or 5 ppm. After ED, the removed pulp was added to the ED-treated juice and its properties, including electrical conductivity, acidity, pH, total soluble solids (TSS), color, amino acids, and selected aroma compounds, were determined and compared with those of the untreated juice. ED could reduce the nitrate content of 1 L of pineapple juice from an initial value of 50 ppm to less than 5 ppm within 30 min. A significant decrease in the electrical conductivity, acidity, pH, TSS, and yellowness, but a significant increase in the lightness, of the juice was observed upon ED. Concentrations of almost all amino acids of the ED-treated juice significantly decreased. The concentrations of 8 major compound contributors to the pineapple aroma also significantly decreased. Adding the pulp back to the ED-treated juice increased the amino acids concentrations; however, it led to a significant decrease in the concentrations of the aroma compounds.

Desalination of fish sauce by electrodialysis: effect on selected aroma compounds and amino acid compositions.

UNLABELLED: Fish sauce is an ingredient that exhibits unique flavor and is widely used by people in Southeast Asia. Fish sauce, however, contains a significant amount of salt (sodium chloride). Recently, electrodialysis (ED) has been successfully applied to reduce salt in fish sauce; however, no information is available on the effect of ED on changes in compounds providing aroma and taste of ED-treated fish sauce. The selected aroma compounds, amino acids, and sensory quality of the ED-treated fish sauce with various salt concentrations were then analyzed. The amounts of trimethylamine, 2,6-dimethylpyrazine, phenols, and all carboxylic acids except for hexanoic acid significantly decreased, whereas benzaldehyde increased significantly when the salt removal level was higher. The amounts of all amino acids decreased with the increased salt removal level. Significant difference in flavor and saltiness intensity among ED-treated fish sauce with various salt concentrations, as assessed by a discriminative test, were observed. PRACTICAL APPLICATION: Information obtained in this work can serve as a guideline for optimization of a process to produce low-sodium fish sauce by ED. It also forms a basis for further in-depth sensory analysis of low-sodium fish sauce.

Electrodialysis desalination of fish sauce: electrodialysis performance and product quality.

Fish sauce has a unique, pleasant flavor, but contains high levels of sodium chloride, which is nowadays not desirable for health-conscious consumers. Although many researchers have attempted to solve this problem by substituting sodium with potassium in fish sauce, potassium-based products are still unsuitable for patients with kidney disease. Thus, electrodialysis (ED) desalination of fish sauce was carried out. The rate of salt removal, evolution of total soluble solids, and electrical conductivity of the electrodialysis-treated fish sauce were investigated. Moreover, the system performance in terms of yield, energy consumption, and current efficiency were examined. Density, viscosity, ion concentrations (that is, Na(+), K(+)), total nitrogen, amino nitrogen, and color were investigated at various values of input voltage (6, 7, and 8 V) and remaining salt concentration (22%, 18%, 14%, 10%, 6%, and 2%[w/w]). The results indicated that an increase in the input voltage led to an increase in the rates of salt removal, electrical conductivity, and total soluble solids. The energy consumption increased whereas current efficiency and yield decreased significantly with an increase in input voltage and the salt removal level. Physicochemical properties of the treated fish sauce, in terms of the total soluble solids, density, viscosity, ion concentrations (that is, Na(+), K(+)), total nitrogen, and color were significantly affected by the input voltage and the salt-removal level.