tannins and malic-acid

Absorbance-transmission and fluorescence excitation-emission matrix (A-TEEM) spectroscopy was investigated as a rapid method for predicting maturity indices using Cabernet Sauvignon grapes produced under four viticulture treatments during two growing seasons. Machine learning models were developed with fused spectral data to predict 3-isobutyl-2-methoxypyrazine (IBMP), pH, total tannins (Tannin), total soluble solids (TSS), and malic and tartaric acids based on the results from traditional analysis methods. Extreme gradient boosting (XGB) regression yielded R

Topics: Machine Learning; Tannins; Vitis; Wine

Astringents (alum, malic acid, tannic acid) representing 3 broad classes (multivalent salts, organic acids, and polyphenols) were characterized alone, and as 2- and 3-component mixtures using isoboles. In experiment 1, participants rated 7 attributes ("astringency," the sub-qualities "drying," "roughing," and "puckering," and the side tastes "bitterness," "sourness," and "sweetness") using direct scaling. Quality specific power functions were calculated for each stimulus. In experiment 2, the same participants characterized 2- and 3-component mixtures. Multiple factor analysis (MFA) and hierarchical clustering on attribute ratings across stimuli indicate "astringency" is highly related to "bitterness" as well as "puckering," and the subqualities "drying" and "roughing" are somewhat redundant. Moreover, power functions were used to calculate indices of interaction (I) for each attribute/mixture combination. For "astringency," there was evidence of antagonism, regardless of the type of mixture. Conversely, for subqualities, the pattern of interaction depended on the mixture type. Alum/tannic acid and tannic acid/malic acid mixtures showed evidence of synergy for "drying" and "roughing"; alum/malic acid mixtures showed evidence of antagonism for "drying," "roughing," and "puckering." Collectively, these data clarify some semantic ambiguity regarding astringency and its subqualities, as well as the nature of interactions of among different types of astringents. Present data are not inconsistent with the idea that astringency arises from multiple mechanisms, although it remains to be determined whether the synergy observed here might reflect simultaneous activation of these multiple mechanisms.

Topics: Adolescent; Adult; Alum Compounds; Astringents; Dose-Response Relationship, Drug; Female; Humans; Malates; Male; Middle Aged; Tannins; Taste; Taste Perception; Xerostomia

Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity. The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency.

Topics: Hydrogen-Ion Concentration; Malates; Plasticizers; Plastics; Polyethylene Terephthalates; Polyvinyl Chloride; Refuse Disposal; Tannins; Temperature

Red muscadine (Vitis rotundifolia Michx.) juices with natural organic, phenolic acids and polyphenol compounds were tested against Cronobacter sakazakii. The concentration of total phenolic compounds of commercial baby juices ranged from 176.7 to 347.7 mg/mL. Commercial baby juices showed poor antimicrobial activity, reducing less than 1-log of C. sakazakii in juice samples for 2 h at 37 degrees C. Red muscadine juices, regardless of processing methods (filtration, pasteurization, and sterilization), achieved a 6-log reduction of C. sakazakii in the same time period (2 h). The mixture of synthetic organic acids (malic and tartaric acids) and polyphenolic acid (tannic acid) showed strong antimicrobial activity against C. sakazakii. Among synthetic organic acids, tannic acid was undetected in commercial baby juices. Tannic acid showed the highest antimicrobial activity (1.4- to 3.8-log reduction) against C. sakazakii, while malic and tartaric acids showed less than 0.5-log reduction. These results suggest that red muscadine juice could be utilized as a natural antimicrobial in baby food formulations to inhibit C. sakazakii.

Topics: Anti-Infective Agents; Beverages; Cronobacter sakazakii; Ellagic Acid; Flavonoids; Food Handling; Food Microbiology; Food Preservatives; Fruit; Humans; Hydrogen-Ion Concentration; Infant; Infant Food; Malates; Phenols; Polyphenols; Resveratrol; Stilbenes; Tannins; Tartrates; Vitis

The objectives of this research were to show the anti-Escherichia coli O157:H7 effect of fresh (FRMJ) and processed red muscadine (Vitis rotundifolia) juice (PRMJ) and to discern the active compounds responsible for anti-E. coli O157:H7.. Polar and phenolic compounds of FRMJ and PRMJ were analysed by high-performance liquid chromatography. Antibacterial activity of FRMJ, PRMJ, their polar and polyphenol fractions, individual synthetic acids and their mixture with or without sugars were investigated on E. coli O157:H7. FRMJ and PRMJ inactivated (P < or = 0.05) 5-log cocktail cells of E. coli O157:H7 within 4 h at 37 degrees C. Polar fractions that contained malic, tartaric and tannic acids showed strong antimicrobial activity (P < or = 0.05) against E. coli O157:H7. Tannic acid among the synthetic acids showed the highest antimicrobial activity against E. coli O157:H7.. FRMJ, PRMJ and their polar compounds showed strong anti-E. coli O157:H7 activity.. Earlier findings have failed to show any anti-E. coli O157:H7 effect of grape juice without adding preservatives. Our findings show that red muscadine juice has natural antibacterial substances and suggest that these can be used as active antimicrobial ingredients against E. coli O157:H7 in nonalcoholic beverages.

Topics: Anti-Bacterial Agents; Beverages; Chromatography, High Pressure Liquid; Colony Count, Microbial; Dicarboxylic Acids; Escherichia coli O157; Food Microbiology; Food Preservation; Malates; Tannins; Tartrates; Vitis