Applying Different Vinification Techniques in Teran Red Wine Production: Impact on Bioactive Compounds and Sensory Attributes

Six different vinification treatments, including a control treatment (7-day standard maceration) (K7), were performed to study the effects of non-standard techniques on bioactive compounds and sensory attributes of Teran red wine. Pre-fermentative mash cooling (8 °C; 48 h) and heating (50 °C; 48 h) followed by prolonged post-fermentative maceration of 13 days (C15;H15) or 28 days (C30;H30) were applied. In another treatment, after cooling, saignée was performed followed by 13-day prolonged maceration (CS15). Wine phenols and vitamins were analyzed by HPLC-DAD-FLD, minerals by ICP-OES, and sensory analysis was performed using the QDA and 100-point O.I.V./U.I.O.E. methods. Obtained results showed total phenolic concentration was the highest in the H30 treatment. The concentration of anthocyanins, flavan-3-ols and phenolic acids was significantly higher in wines of all vinification techniques compared to the control. Stilbene content was highly affected by pre-fermentative heating. Treatments CS15, H15, C30 and H30 resulted in the highest scores by both the QDA and 100-point sensory methods. The obtained results suggest that advanced non-standard vinification techniques have a significant impact on Teran wine by enhancing its composition of bioactive compounds and improving its sensory profile, which gives it an additional market value. Furthermore, a comprehensive comparison of such techniques applied simultaneously in one study is of substantial importance for additional research in wine production.

Kaempferia galanga L.: Progresses in Phytochemistry, Pharmacology, Toxicology and Ethnomedicinal Uses

K. galanga is an aromatic medicinal herb. It is locally to India and distributed in China, Myanmar, Indonesia, Malaysia, and Thailand. K. galanga is a Traditional Chinese Herb Medicine (TCHM), which has been applied to treat cold, dry cough, toothaches, rheumatism, hypertension and so on. In addition, it has been used widely as spices since its highly aromas. The aim of this review is to compile and update the current progresses of ethnomedicinal uses, phytochemistry, pharmacology and toxicology of K. galanga. All the data on K. galanga were based on different classical literary works, multiple electronic databases including SciFinder, Web of Science, PubMed, etc. The results showed that ninety-seven compounds have been identified from rhizome of K. galanga, including terpenoids, phenolics, cyclic dipeptides, flavonoids, diarylheptanoids, fatty acids and esters. Modern pharmacology studies revealed that extracts or secondary metabolites of the herb possessed anti-inflammatory, anti-oxidant, anti-tumorous, anti-bacterial, and anti-angiogenesis effects, which were closely related to its abundant ethnomedicinal uses. In conclusion, although previous research works have provided various information of K. galanga, more in-depth studies are still necessary to systemically evaluate phytochemistry, pharmacological activities, toxicity and quality control of this herb.

Diversity of Italian red wines: A study by enological parameters, color, and phenolic indices

An extensive survey was conducted on 110 Italian monovarietal red wines from a single vintage to determine their standard compositional, color, and phenolic characteristics, analysing more than 35 parameters evaluated through methods commonly used in the wine industry. 'Primitivo' achieved the highest average alcohol strength (15.4% v/v) and dry extract values, while 'Cannonau' showed the lowest total acidity. 'Corvina' had the lowest phenolic content (1065 mg/L by Folin-Ciocalteu assay), remarkably different from the highest found in 'Sagrantino' (3578 mg/L), the latter being also the richest variety in both proanthocyanidins and vanillin-reactive flavanols. 'Teroldego' wines were the richest in both total and monomeric anthocyanins (702 and 315 mg/L, respectively), followed by 'Aglianico' and 'Raboso Piave', while 'Corvina', 'Nebbiolo', and 'Nerello Mascalese' were the poorest. 'Montepulciano' and 'Sangiovese' showed intermediate values for the majority of the parameters analyzed. A multivariate PCA-DA approach allowed achieving both a classification of the different wines as well as the discrimination of 'Sangiovese' wines produced in two regions (Emilia Romagna and Toscana) that returned a 42-66% success rate depending on the zone considered. Taking into account the number and diversity of the wines analyzed, a correlation study helped in better understanding the underlying relations between the most common and widespread analytical techniques for phenolic and color determinations.

Analysis of total polyphenols in wines by FIA with highly stable amperometric detection using carbon nanotube-modified electrodes

The use of glassy carbon electrodes (GCEs) modified with multi-walled carbon nanotube (CNT) films for the continuous monitoring of polyphenols in flow systems has been examined. The performance of these modified electrodes was evaluated and compared to bare GCE by cyclic voltammetry experiments and by flow injection analysis (FIA) with amperometric detection monitoring the response of gallic, caffeic, ferulic and p-coumaric acids in 0.050 M acetate buffer pH 4.5 containing 100 mM NaCl. The GCE modified with CNT dispersions in polyethyleneimine (PEI) provided lower overpotentials, higher sensitivity and much higher signal stability under a dynamic regime than bare GCEs. These properties allowed the estimation of the total polyphenol content in red and white wines with a remarkable long-term stability in the measurements despite the presence of potential fouling substances in the wine matrix. In addition, the versatility of the electrochemical methodology allowed the selective estimation of the easily oxidisable polyphenol fraction as well as the total polyphenol content just by tuning the detection potential at +0.30 or 0.70 V, respectively. The significance of the electrochemical results was demonstrated through correlation studies with the results obtained with conventional spectrophotometric assays for polyphenols (Folin-Ciocalteu, absorbance at 280 nm index and colour intensity index).

Single-drop and nanogram level determination of sulfite (SO3(2-)) in alcoholic and nonalcoholic beverage samples based on diffuse reflectance fourier transform infrared spectroscopic (DRS-FTIR) analysis on KBr matrix

The diffuse reflectance Fourier transform spectroscopic (DRS-FTIR) method, using potassium bromide matrix, has been developed for the one-drop microdetermination of sulfite in beverage samples. The present method is very simple, rapid, and precise for the determination of sulfite. The nanogram level of sulfite determination is based on the selection of a quantitative analytical peak at 495 cm (-1) among the three observed vibrational peaks obtained by diffuse reflectance Fourier transform infrared spectroscopy (DRS-FTIR). As little as a single drop of sample is sufficient for quantitative analysis of sulfite. The limit of detection (LOD) and the limit of quantification (LOQ) of the method are found to be 8 and 40 ng of SO 3 (2-) 0.1 g (-1) of KBr matrix, respectively. The linear range of the method (LR) as well as the LOD based on the concentration of sulfite in the solution are 5-500 and 0.8 microg/mL, respectively. The precision in terms of standard deviation and relative standard deviation value at a level of 100 ng of SO 3 (2-) 0.1 g (-1) of KBr for n = 10 are found to be 2 ng of SO 3 (2-) and 2.3%, respectively. The relative standard deviation ( n = 10) for the determination of sulfite in beverage samples available in the local market was observed to be in the range of 2.4-7.8%. The method is free from interionic effects of foreign species. No sample pretreatment is required in this method. The proposed method avoids the requirement of large numbers and bulk amounts of reagents. The method is well-suited to the need of green chemistry.

Determination of ethyl alcohol content in red wines with an optical alcohol meter based on nanostructured silicon

A rapid analytical method for selectively monitoring ethyl alcohol in red wines without sample pretreatment, based on the use of an optical sensor, has been developed exploiting a porous silicon microcavity. The optical structure, realized by alternating layers of different porosities, was stabilized by thermal oxidation, and the resonant peak shift of the microcavity (projected at 600 nm) was monitored in the presence of more than 20 red wines. The resonant peak shows an increasing red shift depending on the wine alcoholic strength, which is ascribable to a change of refractive index due to physisorption/condensation of ethanol vapors inside the pores' structure. The linear response of the PS oxidized microcavity to the wine alcoholic strength insures the determination of the ethanol amount with a high accuracy and reliability. The calculated values differ by less than 0.5% to those obtained with the official method in accordance with the limits imposed by European laws. Moreover, a user-friendly interface, allowing the sensor to be used by unskilled persons, and portable packaging, able to ensure in situ measurements, have been developed.