Monthly Archives: July 2012

The Effect of Irrigation on the Chemical Composition of Grapes

Posted on July 31, 2012 by Becca| 4 Comments

Every chemical compound in grapes and in wine play some role in the life of the grape/wine, be it during physiological processes during the growth stage, or in the finished wine itself, where it may contribute to the taste and flavor of the wine or the stability of the beverage over time.  For example, anthocyanins are responsible for the color of the grape berries, and ultimately for the finished wine.  Also, flavonols, while they are colorless in the skins of grapes, they are thought to act as a sort of shield against UV radiation.  The exact composition of these compounds in grapes and wine depend on a variety of factors, including grape variety/genetics, environmental factors, and viticulture and winemaking practices.  Studies have also suggested that anthocyanin and flavonol composition is a function of grape growth and skin characteristics.

http://www.environment.gov.au/water/
topics/images/drip-irrigation.jpg

Most research to date has focused on the phenolic composition of grapes and wine, with very little focus on the many remaining chemical compounds in the fruit and finished beverage.  Phenolics should not be the only thing considered during these research studies, as there is likely a synergistic effect between multiple compounds in the system.  Understanding of the full chemical composition of grapes and wines are important not only from a purely scientific standpoint, but also for the grape grower and winemaker due to the direct effects on fruit and wine quality.

The goals of the study presented today were to determine the effect of irrigation management (a viticultural factor that may possibly alter the chemical composition of grapes/wine) on plant yield and physiology, as well as grape berry morphological characteristics, polyphenol and metal composition.  The study also sought to determine the absence of irrigation all together could have an effect on grape quality.

Methods

The experiment was performed in 2008 in a 5 year old vineyard in Montegiordano Marina, Southern Italy.  The climatic conditions there are considered “very hot” (climatic region 5).

The experimental vineyard plot was 0.3ha, with 10 rows of spur-pruned vines trained to a permanent horizontal unilateral cordon.  Distance between vines was 2.5m with 1m between rows.  Final plant density was 4000 vines per hectare.  Rows were planted in a north-south orientation.

Half of the plants were subject to irrigation from the early stages of fruit set to veraison using water amounts equal to 100% of cultural evapotranspiration.  Specifically, this equaled 24L per plant per each irrigation event (10 total) at 5 day intervals.  The other half of the plants were not subject to irrigation.

Meteorological variables that were measured or calculated were: temperature, rainfall, and photosynthetic photon flux density.  Physiological characteristics measured or calculated were leaf-to-air vapor pressure deficit, stem water potential (in order to determine plant water status), leaf gas exchange, chlorophyll florescence, basal florescence yield in dark-adapted leaves, maximal florescence yield in dark and light conditions, maximum quantum yield of PSII photochemistry in dark-adapted leaves, and finally the effective quantum yield of PSII in light-adapted leaves.

At harvest, 30 plants per treatment were randomly selected and the following were measured/calculated: number of clusters and yield per plant, cluster weight, number of berries per cluster, total berry weight per cluster, and the number of leaves per shoot.  For each plant, 3 clusters were randomly selected.

Berries from each cluster were separated into different weight categories: 1) less than 0.60g; 2) between 0.60 and 0.90g; 3) between 0.90 and 1.25g; and 4) greater than 1.25g.  For each plant, 20 grapes per weight class were randomly selected to measure/calculate berry fresh weight, berry diameter at the “equator”, and berry diameter at the “poles”.  The following characteristics were calculated for the berries: surface, volume, surface/volume ratio, the ratio of berry surface/berry weight, and the ratio of skin weight/berry weight.  Skin thickness and soluble solid content of berries was also measured.

For anthocyanin and flavonol extraction and analysis, three clusters per plant were randomly selected and berries separated into the aforementioned weight categories.  Anthocyanins and flavonols were measured, as well as levels of iron, copper, zinc, and calcium.

Results

(Note: I’m leaving out many exact details about values due to space limitations, but if you need to know exact numbers/values of any item presented in the results, just ask and I’ll see if those details are available and will let you know).

  • The growing season was marked with high temperatures and low rainfall.

o   Max temperatures ranged between 15.3 and 38.5oC.

o   Min temperatures ranged from 12.3 and 29.1oC.

o   Rainfall during the experimental growing season was a very low 21.9mm.

  •  There were no significant differences between irrigated and not irrigated plants in regards to net photosynthesis.
  • There were no significant differences in transpiration values between either of the treatments.
  • There were no significant differences in stomatal conductance between either of the treatments.
  • Maximum quantum yield of photosystem II and actual quantum yield of PSII reaction centers in leaves were not affected by irrigation treatment.
  • Mean numbers of clusters per plant were not different between treatment groups.
  • Yield per plant, cluster weight, and total berry weight were significantly different between treatment groups, with higher values occurring in the irrigation group.

o   Irrigation significantly increased the frequency of grapes with greater than 1.25g mass and reduced the frequency of grapes with less than 0.6g mass.

  • Irrigation treatment significantly affected berry fresh weight and skin fresh weight.

o   Irrigation significantly affected berry surface/volume ratios, and were significantly higher in irrigated plants.

o   Skin fresh weights were higher in non-irrigated plants, which resulted in a decrease in skin specific surface and increased in skin specific weight.

o   For the two intermediate weight categories, there were significant differences between the two treatment groups were noted for seed weight per berry as a result in the differences between seed number per berry.

§  There were more seeds in non-irrigated plants than in the irrigated treatment group.

  •  Soluble solid content was significantly higher in the non-irrigated group than the irrigated group.
  • Total anthocyanins were significantly higher in the non-irrigation group than the irrigation group.

o   This result was positively correlated with berry weight.

  • Significant differences were found in the concentrations of petunidin-3-O-acetylglucoside, peonidin-3-O-acteylglucoside, and petunidin-(6-O-caffeoyl)glucoside.

o   Levels were higher in non-irrigated plants (9x, 18x, and 10x, respectively).

  • Levels of single anthocyanins increased with decreasing berry weight.
  • Berries from irrigated plants had significantly lower ratios of acetylated anthocyanins/coumaroylated anthocyanins.
  • Total flavonols were not significantly different between the two treatment groups.

o   Levels of single flavonols were significantly higher in heavier berries.

  • Iron, copper, and zinc levels were significantly higher in berries from irrigated plants than from non-irrigated plants.
  • Calcium levels were not significantly different between the two treatment groups.
  • Metal levels significantly decreased in increasing berry weight.
  • There were no differences in berry skin thickness between either treatment group.
  •  No significant differences were found in the number of skin layers and thickness of the berries between either treatment group.

Conclusions

One undesired outcome of this experiment was the near drought-like conditions of the weather during the experiment.  This resulted in plants being subject to moderate-severe water stress, which caused some leaf necrosis and can influence the micro-climate at the cluster.  Specifically, it has been shown that this type of stress may affect berry size and chemical composition, thereby potentially changing the outcomes of some of the tests, and making it generally more difficult to tease out cause and effect.

The results of this study also showed that total anthocyanins were higher in grapes from non-irrigated plants than in irrigated plants.  This results in a positive influence on the long-term color stability of wines, as these compounds working in concert with tannins and flavonols to strengthen color stability in the aging beverage.  Additionally, increases in these compounds and well as the observed increases in petunidin-3-O-acetylglucoside and peonidin-3-O-acteylglucoside, can have positive sensory benefits to the finished wine as well.

Another interesting result from this study is that metal levels significantly decreased with increasing berry weight.  Excess metal concentrations in wine are known to cause negative sensory characteristics, delay the fermentation process, and increase instability.  Fe, Cu, and Zn were all found to be significantly lower in grapes from non-irrigated plants than in irrigated plants.

Overall, the results of this study suggest that less irrigation increased the quality of the finished wine.  Specifically, little to no irrigation results in lower berry yield and a reduction in berry size without negatively affecting grape quality in terms of the chemical composition of the grapes.  This study confirms what many in the wine industry in that grapes grown under water stress conditions can result in higher quality wine (provided there are no set-backs during the winemaking process).  Even though many already knew less water is better, this study paints a good picture of exactly how the chemical composition of the grapes changes when subject to these drier conditions.

There are many more results to this study that I did not cover due to time and space considerations, but I’d love to hear your thoughts or questions on them, even if I didn’t specifically cover it.  What do you all think of the study?  What would you like to have seen done differently (if anything).  I, for one, would have liked to see them create experimental wines from these two treatment groups and measure the same compounds to see how irrigation actually alters the chemical composition of the finished wine and not just the starting point grapes.  Do these differences carry through the winemaking process?  Are different winemaking techniques better suited to maintaining the original/similar chemical composition of the grapes?

I’d love to hear what you think! Please feel free to comment below!

Source: Sofo, A., Nuzzo, V., Tataranni, G., Manfra, M., De Nisco, M., and Scopa, A. 2012. Berry morphology and composition in irrigated and non-irrigated grapevine (Vitis vinifera L.). Journal of Plant Physiology 169: 1023-1031.

DOI: 10.1016/j.plph.2012.03.007
I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!

Posted in Chemistry

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Different Vineyard Training Systems Alter Susceptibility of Grapes to Powdery Mildew

Posted on July 27, 2012 by Becca| 4 Comments

One of the most common pests to vineyards all over the globe is powdery mildew (Erysiphe necator Schwein).  It is responsible for causing widespread destruction in nearly every viticultural area worldwide, and is a fungus that is able to develop in a variety of temperatures and humidity levels.  Though it is present in nearly every corner of the globe, the severity of the infection from vineyard to vineyard is dependent upon a variety of factors, including the variety of grape, the vigor of the vines, the type of protective chemicals applied, and the weather conditions.

http://www.bioseaoz.com.au/images/
DiseaseImages/PowderyMildewOnGrapes.jpg

Some studies have found that the training system used in the vineyard has a significant effect on powdery mildew development, by altering the microclimate in the cluster area.  It appears as though light intensity and UV radiation appear to contribute to the changes in powdery mildew development severity, both of which have also been shown to affect the chemical composition of the grapes themselves.   Specifically, work done by the authors of the paper presented today found that there were significantly lower powdery mildew infections in grapes trained in the free canopy system versus grapes trained in the vertical shoot positioned system.

The article presented today is a very short article with the objective of investigating whether or not the difference in infection incidences as described above were due to light intensity itself, the susceptibility of the berries, or both.

Methods

The study was performed in June 2003 at an experimental vineyard in the Golan Region of Northern Israel.  Grapevines planted in this vineyard were Cabernet Sauvignon and Chardonnay (both with good susceptibility to powdery mildew).

Half of the vineyard was subject to a vertical positioned system, while the other half was left as a free canopy, though topped to one meter in length after fruit set and hedged no more than twice during the growing season.  Dates of bud burst, flowering, and fruit set were the same for both training systems.

Figure 1 from Zahavi and Reuveni, 2012

Experiment 1: Clusters were picked when the diameter of the berries were 3-5mm.  Thirty to forty berries from each training system were selected and placed in plastic boxes.  Berries were then inoculated with powdery mildew.  Twenty more berries were placed in plastic boxes but not inoculated with the fungus to serve as a control to monitor natural infections from the field.  Percent of infected berries was then calculated 7-9 days after inoculation with powdery mildew.

Experiment 2:  Clusters were inoculated in the exact same manner as in Experiment 1, however, 1-2 hours after inoculation, berries were returned to the vineyard and either placed on the cluster zone/vine cordon of their original training system or on vine cordon of the opposite training system for 8 hours.  After this time, berries were brought back to the laboratory and disease development was monitored 7-9 days after.

Results

  • For the first experiment, incidence of powdery mildew was significantly higher on berries originating from the vertical positioned vines than those originating from the free canopy system.
  •  For the second experiment, berries that originated from the vertical positioned vines and then incubated in those same vines were significantly more infected with powdery mildew than those berries that originated from the free canopy vines and incubated in either of the vine position systems.
  • Also in the second experiment, berries that originated from the vertical positioned vines that were incubated in the free canopy system vines had an intermediate level of powdery mildew disease severity.
  • Powdery mildew did not develop on control berries that were not inoculated.

Conclusions

The results of this study found that grapes originating from a free canopy system, which has a greater exposure to light, resulted in lower susceptibility to powdery mildew infection than grapes originating from vertically positioned vines, which have a denser canopy that does not allow in as much light. 

By transferring inoculated free canopy grapes into a vertical positioned set up, powdery mildew development decreased as a result of a pre-conditioning effect on the grapes.  In other words, this means that the grapes were less susceptible to infection after being exposed to higher intensity of light from the free canopy system.  The authors conclude by stating that the conditions in which grapes develop influence the severity of infection by powdery mildew.

Being a short experiment, there are certainly many more questions that these results raised which cannot be answered with the results found.  For example, how do the different training systems affect the chemical and sensory characteristics of the wine?  Are there any differences?  Since it appears grapes grown under a vertical positioned system are more susceptible to powdery mildew than grapes grown under a free canopy system, it suggests that perhaps there are some chemical defense changes within the plant, which may or may not affect the overall sensory characteristics of a wine made from those grapes.

Would the results be the same for each and every variety of grape out there?  Or are Cabernet Sauvignon and Chardonnay more susceptible to powdery mildew invasion under a vertical positioned system while say Riesling and Malbec are more susceptible under a different training system?  I would think it once again boils down to plant defensive chemistry, but we’d need some further studies examining many more grape varieties to be sure.

What about other training systems?  What is the “hierarchy of susceptibility” for powdery mildew in Vitis vinifera grapes? 

The results of this study are not to suggest that one should switch from a vertical positioned system to a free canopy, however without any extra chemical defense (fungicides, etc), it might be recommended that one reconsider the training system that is employed at one’s vineyard.  There are, of course, many other factors that any given training system will affect, thereby requiring one to weigh all the pros and cons before choosing any particular method.

I’d love to hear what you all think of this study!  What questions did this study raise for you?  Please feel free to comment below!

Source: Zahavi, T., and Reuveni, M. 2012. Effect of grapevine training systems on susceptibility of berries to infection by Erysiphe necator. European Journal of Plant Pathology 133: 511-515.

DOI: 10.1007/s10658-012-9938-z



I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!

Posted in Viticulture

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Casein Levels in Commercial Wines Not Enough to Elicit Allergic Reaction in Milk Allergy-Stricken Adults

Posted on July 24, 2012 by Becca| 3 Comments

Food allergies are very common in both children and adults, and some fear that wine can be a potential allergenic threat to certain individuals.  From the alcohol in the wine to the chemicals and reagents used in the winemaking process, determining levels of potential allergens in wine for labeling and warning purposes has become the main concern spearheading several legislative measures in Europe and elsewhere all over the globe.

http://i.istockimg.com/file_thumbview_approve/
13418867/2/stock-illustration-13418867-
cartoon-cow-as-a-milk-man.jpg

Milk allergies, which are different from milk intolerances, occur throughout the globe though are more common in children than in adults.  This allergy, in fact, is quite rare, affecting only 0.062% of Italian adults.  In white winemaking, potassium caseinate is often used as a fining agent and is derived from milk.  Potassium caseinate works as a fining agent by binding to compounds that cause cloudiness in wine and allow those compounds to be removed and the final wine clarified.  During this process, there is a chance that not all of the fining agent is removed, thereby causing a potential health risk to those that suffer from milk allergies.

Alternatives to potassium caseinate (or any casein-based compounds) are available to use during the winemaking process to help avoid possible negative health risks due to milk allergy in certain individuals, however, do wines even possess high enough levels of the compound to elicit an allergic response?  The paper presented today aimed to examine the levels of caseinate in many commercial wines, to determine if residual levels are high enough to potentially cause allergic reactions in adults and if adding a warning label to a wine bottle is a necessary precaution. 

Methods

Both experimental and commercial wines were examined in this study.  Experimental wines were put into treatment groups as follows: untreated controls; samples fined with 20g/h L of commercical caseinate; samples fined with 50g/h L; and samples with both of these caseinate dosages with 0, 30, 60, or 90g/h L of bentonite added.

2 liters of wine were first combined with caseinate (at 0, 20, or 50g/h L) then kept at room temperature for 24 hours.  After this time, bentonite was added (at 0, 30, 60, or 90g/h L) and then kept at room temperature for another 24 hours.  All experimental wines were passed through membranes with a pore size of 3μm.  In total, there were 16 experimental wines and 14 controls (not treated with casein).

Commercial wines were sent to the researchers from all over Italy with the requirement that all wines had be fined with casein.  A total of 59 white wines, 2 rosé wines, and 2 red wines were sent in from around Italy.  All commercial wines were filtered through membranes of pore sizes less than or equal to 1um.  Commercial caseinate used in wines were: alpha caseinate, caseinato di potassio, Caseo Cell, Clarasi DC, Clarito Spray Dry, Clarito SP, Kaseomax, Micron 96, Micron XL, potassium caseinate S, Protoclar, and Vinpur Special.

The following characteristics of the wines were measured: alcohol by volume, total alcoholic strength, sugar content, total acidity, volatile acidity, pH, ash, total dry extract, reduced extract, and total phenolic content.

Casein was measured using several methods, including SDS-page/western blotting and ELISA.  Tests were performed in triplicate.

The entire experiment included 16 experimental wines and 63 commercial wines, all fined with caseinates, with or without bentonite, and microfiltered.  Untreated wines were used as controls.

Results

  • SDS-page/western blotting proved to be an ineffective method for measuring casein in wine, as the binding capabilities of the proteins used in that analysis were nonspecific and bound to many more compounds than casein itself, thereby making it impossible to distinguish what compounds were casein, and what compounds were not.
  •  Results indicated that the antibodies used in the ELISA analysis were very specific to caseins and β-caseins, which indicates that detection of casein in commercial wines is guaranteed (according to the authors) using this method.
  • Control wines (no casein added) were found to be completely free of casein by ELISA analysis.
  • All (experimental and commercial) wines were found to be free from detectable levels of allergenic casein residues (less than 0.28ppm).

o   This result was the same of all wines, regardless of the varietal, dosage of fining agent, and winemaking practices.

Conclusions

According to the results of this study, there was no detectable casein residues remaining (less than 0.28ppm) in all wines studied.  This suggests that those individuals with milk allergies should not be concerned about if a wine is treated with casein during the winemaking process.  According to the authors, clinical trials should not need to be performed, since casein was not present in detectable levels that would have any effect on those very few adults with milk allergies.

The authors put forth a “worst case scenario” situation in order to stress how little casein is actually present in Italian commercial wines which I will describe here.  Clinical evidence has shown that the 0.6mg of milk protein (casein) can cause major problems in some children with milk allergies (children are more sensitive than adults, in general, to milk protein).  If an adult were sensitive to that level of casein/milk protein, they would have to consume 1.2 liters of wine in a short period of time in order to elicit an allergic reaction.  Since the adult threshold for casein/milk protein sensitivity is more along the levels of 10mg (instead of 0.6mg), it is near impossible for commercial wines to elicit allergic reaction in those individuals affected by a milk protein allergy.

I’d be curious to see an analysis of casein levels from all over the world; however, I’m fairly certain that we’d see the same results that we are seeing in this study.  Individuals with a true allergy to milk (NOT a lactose intolerance, which is a different medical problem) should not be concerned if a wine was treated with casein during the winemaking process, nor there a need to require labeling a wine as having undergone casein treatment.

I’d love to hear what you all think about this topic!  Please feel free to leave your comments!

Source: Restani, P., Uberti, F., Danzi, R., Ballabio, C., Pavanello, F., and Tarantino, C. 2012. Absence of allergenic residues in experimental and commercial wines fined with caseinates. Food Chemistry 134: 1438-1445.

 

DOI: 10.1016/j.foodchem.2012.03050



I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!

Posted in Health

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Identifying Melatonin in Wine: A “New” Antioxidant with Potential Positive Health Benefits Found

Posted on July 19, 2012 by Becca| 9 Comments

Almost a year ago, The Academic Wino presented an article that examined the role of melatonin in grapes.  Results of that study found that melatonin fluctuates in the grape vine and grapes during the day, and that in order to create a wine with higher levels of melatonin, one must harvest the grapes at an optimum time.  One thing this article did not examine was the levels of melatonin in wine itself, and whether or not these levels would be detectable in the finished wine after going through the winemaking process.

http://upload.wikimedia.org/wikipedia/commons
/thumb/1/14/Melatonin2.svg/
220px-Melatonin2.svg.png

Melatonin is a compound found in many life forms that is synthesized from L-tryptophan metabolism via serotonin (think “turkey coma”) and is considered both an antioxidant and a compound that aides in regulating circadian rhythms.  In humans (and other vertebrate species), melatonin is synthesized by the pineal gland and secreted into the blood stream.  Melatonin tends to be highest in younger humans/vertebrates, and decreases with age.  Melatonin is also found in the leaves, fruits, and seeds of plants, the purpose of which is not entirely understood, but some have speculated is a defensive mechanism against UV light exposure.

Up until recently, melatonin has been found in about 8 grape varieties, though only one study so far has identified melatonin in wine.  The short study presented today aimed to determine whether or not melatonin was present in wine from different grape varieties and to test a few different analytical methods for efficiency and accuracy.

Methods

Wines used in this study were made at the Instituto de Investigación y Formación Agraria y Pesquera in Jerez de la Frontera, Spain.  Grapes were harvested in 2007 at maturity and underwent controlled winemaking procedures at 25oC.  Grape varieties harvested were: Cabernet Sauvignon, Jaen Tinto, Merlot, Palomino Negro, Petit Verdot, Prieto Picudo, Syrah, and Tempranillo.  All wines made were single varietal.

Methods used for analyzing melatonin levels were: ELISA, LC-fluorescence, and LC-ESI-MS/MS.

Eight single varietal wines were analyzed in duplicate by ELISA, and triplicate by all other methods.

Results

  • ELISA analysis indicated that Palomino Negro possessed the highest levels of melatonin out of all wines analyzed.
  • Cabernet Sauvignon, Jaen Tinto, Merlot, Petit Verdot, Prieto Picudo, and Syrah all showed similar levels of melatonin, which ranged from 162pg/mL to 230pg/mL.
  • Due to the complexity of the wines, which contain many primary and secondary metabolites, these compounds can interfere with ELISA results, creating false positives or false negatives when there may or may not be present the compound of interest.

o   Results indicated a 25% false positive rate and a 28.6% false negative rate.

o   These results suggest that ELISA is a poor method for analyzing melatonin in wine, since results were unclear and inaccurate.

  • Unlike ELISA, the LC-Fluorescence method was reliable for analyzing melatonin levels in wine.

o   For Trebbiano wines, the melatonin level determined by LC-Fluorescence was 0.04ng/mL.

  • LC-MS/MS analysis showed that Tempranillo wines contained the highest levels of melatonin.

o   Cabernet Sauvignon, Petit Verdot, Prieto Picudo, and Syrah all had markedly variable levels of melatonin.

o   Melatonin was not found to be present in Jaen Tinto, Merlot, and Palomino Negro wines.

  • LC-MS/MS analysis showed that isomers of melatonin (same molecular formula, but different structure) were found in highest levels in Jaen Tinto wines (32.6ng/mL).

o   ¼ of the melatonin found in Tempranillo wines was in its isomeric form.

o   Small amounts of melatonin isomer were found in Cabernet Sauvignon, Merlot, Palomino Negro, Prieto Picudo, and Tempranillo.

o   There were no melatonin isomers found in Petit Verdot or Syrah.

  • The presence of melatonin in wines was quantitatively and qualitatively extremely diverse.
  • Melatonin in wines was present in its functional form and also in its isomeric form in wines, the levels of which varied greatly depending upon varietal of wine.
  • Melatonin and melatonin isomer levels may be a function of grape variety and winemaking techniques.

Concluding Thoughts

The results of this study were simple in that melatonin is present in wines, though is specific to varietal and potentially winemaking technique.  Levels of melatonin in wines are also highly variable, again due to varietal, winemaking technique, and the method used to collect the data.  According to the results of this study, LC-MS/MS was the best method for determining levels of melatonin in wines, though further analysis would need to be done to ensure repeatability.

So what does it mean if there is melatonin present in wine?  Well, I (and science!) am not 100% sure, but since it often functions as an antioxidant, it would likely join the ranks of the other polyphenols, flavanols, and resveratrol that have all been shown to have incredibly positive health benefits.  Melatonin has been so little studied in wine that it is difficult to determine what other, if any, health benefits it may have in wine.  Are the levels of melatonin present in wine enough to even elicit these health benefits?  There have been no clinical trials focusing on this compound as a function of its health benefits when in wine, so it is hard to say.

I’d love to hear what you all think about this topic.  This study leaves much to be determined, so I’d love to hear how you all interpret these data and how you extrapolate this to real world functionality.

Please feel free to comment below!

Source:  Rodriguez-Naranjo, M.I., Gil-Izquierdo, A., Troncoso, A.M., Cantos, E., Garcia-Parrilla, M.C. 2011. Melatonin: A new bioactive compound in wine. Journal of Food Composition and Analysis 24: 603-608.

 

DOI: 10.1016/j.jfca.2010.12.009

 

 




I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!

Posted in Chemistry

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