scholarly journals Effect of Different Enological Tannins on Oxygen Consumption, Phenolic Compounds, Color and Astringency Evolution of Aglianico Wine

Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4607
Author(s):  
Luigi Picariello ◽  
Alessandra Rinaldi ◽  
Martino Forino ◽  
Francesco Errichiello ◽  
Luigi Moio ◽  
...  

Background: In the wine industry, in addition to condensed tannins of grape origin, other commercial tannins are commonly used. However, the influence of oxygen uptake related to different tannin additions during the post fermentative phase in wine has not been completely investigated. In this study, we evaluated the influence of four different commercial tannins (namely, condensed tannins, gallotannins, ellagitannins and tea tannins) during four saturation cycles. Method: Wine samples were added with four different tannin classes (30 g/hL) as to have 5 different experimental samples: control, gallotannins (GT), condensed tannins (CT), ellagitannins (ET), and tea tannins (TT). The chemical composition of the four commercially available tannin mixtures was defined by means of NMR and high-resolution mass spectrometry. After the addition of tannins, each wine sample was oxidized by air over four cycles of saturation. During the experiment oxygen consumption rate (OCR), sulfur dioxide consumption, acetaldehyde production, phenolic compounds, chromatic characteristics, astringency measured by the reactivity towards saliva proteins and astringency subqualities were evaluated. Results: The experiment lasted 52 days. The addition of tannins influenced the oxygen consumption on the 1st day of the saturation cycles and, in the case of TT, a higher total consumption of oxygen was also detected. Acetaldehyde increased during the experiment while the native anthocyanins decreased throughout the oxidation process. Conclusion: Wines added with tannins featured improved color intensities with respect to the control; the addition of TT, GT and ET slightly promoted the formation of short polymeric pigments; the astringency, determined before and at the end of the experiment, decreased in all the samples, including the control wine, and mostly in the ET and GT samples.

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 21-21
Author(s):  
Scott L Kronberg

Abstract A large variety of plant species contain condensed tannins and a few of these have been developed as improved varieties for grazing or for feeding as long-stem, chopped or pelleted hay or as silage. Extracts of tannin-containing plant materials (e.g. quebracho tannin) and tannin-containing by-products of plant materials (e.g. grape marc) have also been fed to livestock. Interactions between livestock and condensed tannins and associated phenolic compounds are complicated and we have much to learn to understand and manage them better. Although many studies have been done on tannin-livestock interactions, many more are needed and especially studies done in conjunction with tannin chemists. Research to date suggests that very few plant materials have ideal condensed tannins for improving the long-term productivity of ruminant livestock (beyond productivity gains from reduction of internal parasites). Moreover, we know little about nutritional consequences relative to micronutrients such as copper and iron from long-term and frequent intake of condensed tannins. Given that grapes contain condensed tannin and associated phenolic compounds that are important to the wine industry, there is research on these compounds in grapes and wine that may be very useful to livestock scientists and producers who are interested in applying some of their concepts and knowledge to livestock. Some of this information will be discussed in my presentation.


Author(s):  
Grażyna Mazurkiewicz-Boroń ◽  
Teresa Bednarz ◽  
Elżbieta Wilk-Woźniak

Microbial efficiency in a meromictic reservoirIndices of microbial efficiency (expressed as oxygen consumption and carbon dioxide release) were determined in the water column of the meromictic Piaseczno Reservoir (in an opencast sulphur mine), which is rich in sulphur compounds. Phytoplankton abundances were low in both the mixolimnion (up to 15 m depth) and monimolimnion (below 15 m depth). In summer and winter, carbon dioxide release was 3-fold and 5-fold higher, respectively, in the monimolimnion than in the mixolimnion. Laboratory enrichments of the sulphur substrate of the water resulted in a decrease in oxygen consumption rate of by about 42% in mixolimnion samples, and in the carbon dioxide release rate by about 69% in monimolimnion samples. Water temperature, pH and bivalent ion contents were of major importance in shaping the microbial metabolic efficiency in the mixolimnion, whilst in the monimolimnion these relationships were not evident.


2021 ◽  
Vol 22 (9) ◽  
pp. 4366
Author(s):  
Rebecca L. Paszkiewicz ◽  
Richard N. Bergman ◽  
Roberta S. Santos ◽  
Aaron P. Frank ◽  
Orison O. Woolcott ◽  
...  

The authors wish to make the following corrections to this paper [...]


Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 31
Author(s):  
Adelaida Esteban-Muñoz ◽  
Silvia Sánchez-Hernández ◽  
Cristina Samaniego-Sánchez ◽  
Rafael Giménez-Martínez ◽  
Manuel Olalla-Herrera

Background: phenolic compounds are bioactive chemical species derived from fruits and vegetables, with a plethora of healthy properties. In recent years, there has been a growing interest in persimmon (Diospyros kaki L.f.) due to the presence of many different classes of phenolic compounds. However, the analysis of individual phenolic compounds is difficult due to matrix interferences. Methods: the aim of this research was the evaluation of individual phenolic compounds and antioxidant capacity of the pulp of two varieties of persimmon (Rojo Brillante and Triumph) by an improved extraction procedure together with a UPLC-Q-TOF-MS platform. Results: the phenolic compounds composition of persimmon was characterized by the presence of hydroxybenzoic and hydroxycinnamic acids, hydroxybenzaldehydes, dihydrochalcones, tyrosols, flavanols, flavanones, and flavonols. A total of 31 compounds were identified and 17 compounds were quantified. Gallic acid was the predominant phenolic compounds found in the Rojo Brillante variety (0.953 mg/100 g) whereas the concentration of p-hydroxybenzoic acid was higher in the Triumph option (0.119 mg/100 g). Conclusions: the results showed that the Rojo Brillante variety had higher quantities of phenolic compounds than the Triumph example. These data could be used as reference in future phenolic compound databases when individual health effects of phenolic compounds become available.


2021 ◽  
Vol 22 (16) ◽  
pp. 8367
Author(s):  
Hien Lau ◽  
Shiri Li ◽  
Nicole Corrales ◽  
Samuel Rodriguez ◽  
Mohammadreza Mohammadi ◽  
...  

Pre-weaned porcine islets (PPIs) represent an unlimited source for islet transplantation but are functionally immature. We previously showed that necrostatin-1 (Nec-1) immediately after islet isolation enhanced the in vitro development of PPIs. Here, we examined the impact of Nec-1 on the in vivo function of PPIs after transplantation in diabetic mice. PPIs were isolated from pancreata of 8–15-day-old, pre-weaned pigs and cultured in media alone, or supplemented with Nec-1 (100 µM) on day 0 or on day 3 of culture (n = 5 for each group). On day 7, islet recovery, viability, oxygen consumption rate, insulin content, cellular composition, insulin secretion capacity, and transplant outcomes were evaluated. While islet viability and oxygen consumption rate remained high throughout 7-day tissue culture, Nec-1 supplementation on day 3 significantly improved islet recovery, insulin content, endocrine composition, GLUT2 expression, differentiation potential, proliferation capacity of endocrine cells, and insulin secretion. Adding Nec-1 on day 3 of tissue culture enhanced the islet recovery, proportion of delta cells, beta-cell differentiation and proliferation, and stimulation index. In vivo, this leads to shorter times to normoglycemia, better glycemic control, and higher circulating insulin. Our findings identify the novel time-dependent effects of Nec-1 supplementation on porcine islet quantity and quality prior to transplantation.


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