{"id":1464,"date":"2019-12-09T10:35:12","date_gmt":"2019-12-09T14:35:12","guid":{"rendered":"http:\/\/www.techniquesinhomewinemaking.com\/blog\/?p=1464"},"modified":"2026-03-22T06:58:20","modified_gmt":"2026-03-22T10:58:20","slug":"a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel","status":"publish","type":"post","link":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/","title":{"rendered":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel"},"content":{"rendered":"\n

Introduction<\/strong><\/h2>\n\n\n\n

Oak barrels have long been used in winemaking. There exists a natural harmony\namong oak wood compounds, wine constituents, and the oxygen transferred into barrels\nthat, in general, results in greater wines compared to their non-oak-aged\ncounterparts. The main wine constituents of interest here are polyphenols, and\nmore specifically, tannins, the substances responsible for the drying, puckery\nsensation in the mouth, and anthocyanins, the red-color pigment molecules.<\/p>\n\n\n\n

Aside from the plethora of aromas and flavors that oak and particularly\ntoasted oak impart to wine, the infinitesimally small amount of oxygen exchange\nin barrels from the outside environment improves and stabilizes color,\nsmoothens tannins for a softer \u201cmouthfeel,\u201d i.e. the combined sensation of\ntannins, acids, ethanol, and polysaccharides, and improves aging potential. This\noxygen exchange phenomenon is known as micro-oxidation<\/em>;\nthe term micro-oxygenation<\/em> is also\nused interchangeably. Those aromas and flavors also become more concentrated\ndue the slow evaporative loss of ethanol and water \u2014 the \u201cangel\u2019s share.\u201d<\/p>\n\n\n\n

But oak barrels are a significant investment; acquisition costs are\nhigh, they require care and maintenance, and they have a limited lifespan in\nthat they become \u201cneutral\u201d after several uses and no longer impart those much-desired\naromas and flavors.<\/p>\n\n\n\n

Oak powder, chips, staves, cubes, balls, and spirals \u2014 collectively\nreferred to as oak adjuncts <\/em>\u2014 are\ninexpensive alternatives to oak barrels, driving the cost of \u201coak-aged\u201d wines\ndown significantly.<\/p>\n\n\n\n

Oak adjuncts can be used either in inert vessels, such as stainless\nsteel tanks, or neutral oak barrels. There is no oxygen transfer into inert\nvessels and therefore oak adjuncts are only used for imparting oak aromas and\nflavors. In neutral barrels, micro-oxidation still occurs, albeit at a slower\nrate, and can therefore better replicate newer barrels when used with adjuncts.<\/p>\n\n\n\n

There are several other technologies and products that attempt to replicate the benefits of oak-barrel aging. One such technology is micro-oxygenation, known as MOX, which involves injecting minuscule amounts of oxygen into tanks fitted with oak adjuncts, typically long oak staves. Vessels manufactured from HDPE (high density polyethylene) have also been developed to replicate the physics and chemistry of barrels if used with adjuncts. Flextank<\/a> vessels, manufactured by Smak Plastics, Inc.<\/a>, is one such line of products and the focus of this study.<\/p>\n\n\n\n

NOTE:<\/em><\/strong> I use the term <\/em>micro-oxidation to refer to the passive transfer of oxygen through a material and into wine, and <\/em>micro-oxygenation to refer to the deliberate, active injection of oxygen into wine using specialized equipment in conjunction with oak adjuncts.<\/em><\/p>\n\n\n\n

Flextanks<\/strong><\/h2>\n\n\n\n

Flextanks are manufactured from resin into extremely durable polyethylene approved by the USFDA (US Food and Drug Administration) and EFSA (European Food Safety Authority) that, according to Flextank<\/a>, can last up to 20 years, significantly much longer than the useful life of an oak barrel before it becomes neutral. Flextank also claims that these vessels are designed to have a similar oxygen permeation rate, or oxygen transfer rate (OTR), to that of a typical second-year barrel when used at a nominal cellar temperature of approximately 13\u00b0C (55\u00b0F). To my knowledge, there is no published OTR data for Flextank products.<\/p>\n\n\n\n

Flextanks are available in various volumes from cylindrically shaped 55- to 2000-liter (15- to 500-gallon) tanks to egg-shaped maturation tanks and stacking bins. For a complete list of Flextank products, please visit Flextank\u2019s website<\/a>.<\/p>\n\n\n\n

Objectives of this Study<\/strong><\/h2>\n\n\n\n

The objective of this study is to compare the performance of a Flextank\nvessel to that of a second-year barrel, both equipped with an oak adjunct.\nPerformance will be assessed both quantitatively by measuring and analyzing pertinent\nenological parameters and qualitatively by tasting and evaluating the wine\nthroughout the duration of the study. This study is expected to last a minimum\nof 12 months and up to 24 months.<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n
\n
\"\"<\/figure>\n<\/div>\n\n\n

Specifically, a 55-liter (15-gal) Flextank (ECO15\/EM15) and a similarly sized two-year-old French oak Boutes barrel will be used in this study and each equipped with a demijohn-sized WineStix oak stave made from Allier French oak with a medium-plus toast level. The barrel had previously and continuously held two batches of the same wine for approximately 24 months. The wine is a Touriga Nacional sourced from Lodi, California from the 2019 vintage acquired from Musto Wine Grape Company<\/a>. The chemistry of the wine is outlined further down.<\/p>\n\n\n\n

NOTE: <\/em><\/strong>The WineStix were both trimmed by 5 cm (2 in.) so that the one for the barrel could be completely inserted.<\/em><\/p>\n\n\n\n

How the Study Will Be Carried Out<\/strong><\/h2>\n\n\n\n

A Touriga Nacional wine was vinified from frozen must as a single batch<\/em> up to the end of both the alcoholic and malolactic fermentations and stabilization with potassium metabisulfite (K2<\/sub>S2<\/sub>O5<\/sub>). Both the barrel and Flextank were filled with the same wine and WineStix product. To compensate for possibly different oxygen uptake and free sulfur dioxide (FSO2) consumption during the vessel-filling operations, FSO2 and dissolved oxygen (DO) levels were re-measured after the transfers, and FSO2 adjusted back to identical levels and based on pH and DO of the now separate batches.<\/p>\n\n\n\n

NOTE: <\/em><\/strong>The\ndry airlock supplied with the Flextank will be used instead of fitting a\nsilicone bung with a wet airlock on the threaded opening on the lid. Teflon\ntape has been applied to all threaded parts to minimize air ingress and the\npossibility of leakage through the top lid should wine expansion occur. The\nFlextank is equipped with a threaded \u00bd\u201d ball valve and hose barb at the bottom.<\/em><\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n

Both batches will be held at 13\u00b0C\n(55\u00b0F) in a\ntemperature-controlled cellar with relative humidity (RH) between 55% and 75%.<\/p>\n\n\n\n

The barrel will be topped up every two weeks with the same wine\nreserved in a separate vessel. The Flextank should not require any topping\nbeyond possibly a topping in 7\u221210 days after the initial filling and\ninsertion of the WineStix.<\/p>\n\n\n\n

At one-month intervals, pH, FSO2 and DO will be measured in each batch\nto determine FSO2 consumption and oxygen uptake, and then FSO2 will be adjusted\nback to the proper level based on pH and DO.<\/p>\n\n\n\n

At three-month intervals, in addition to the parameters measured at\none-month intervals, total acidity (TA), volatile acidity (VA), total SO2<\/sub>\n(TSO2), ethanol concentration, turbidity, color and phenol index will be\nmeasured. Sensory evaluations will also be performed to assess evolution of\neach wines using qualifiers of appearance, aroma and bouquet, taste, aftertaste\nand overall impression. The tastings will be conducted blind. Both samples will\nbe compared to the base wine aging in a glass carboy, albeit of different\nvolume than the barrel and Flextank, and so, the comparison will not be\ncompletely valid from a scientific perspective.<\/p>\n\n\n\n

The significance of the relevance of the enological parameters is outlined below.<\/p>\n\n\n\n

Regular updates will be posted in this blog and a final report will be published upon conclusion of the study.<\/p>\n\n\n\n

Other Studies<\/strong><\/h2>\n\n\n\n

At least two studies have examined the effects of oxygen transfer through HDPE material. del Alamo\u2010Sanza et al. (2015) and Nguyen et al. (2010) demonstrated the positive effects of micro-oxidation on color parameters. Although del Alamo\u2010Sanza et al. (2015) concluded that HDPE tanks in combination with oak adjuncts are a viable alternative for storing wines, their study compared HDPE tanks to new<\/em> oak barrels and of slightly different volumes (190-L\/50-gal tanks vs. 225-L\/59-gal barrels) for a duration of four months in vessels and two in bottles. And the study by Nguyen et al. (2010) did not consider oak barrels; it only examined HDPE and stainless steel tanks and without the use of oak adjuncts.<\/p>\n\n\n\n

Enological Parameters<\/strong><\/h2>\n\n\n\n

Following is an overview of enological parameters that will be\nmonitored and which could provide clues as to any potential differences in wine\nevolution between the barrel and the Flextank batches.<\/p>\n\n\n\n

Total Acidity (TA)<\/strong>,\nexpressed as tartaric acid equivalents in g\/L, measures the concentration of\nall fixed and volatile acids. Changes in TA would primarily be due to changes\nin volatile acidity (VA) although a drop can occur due to potassium bitartrate\nformation and precipitation. Potassium ion (K+<\/sup>) and tartaric acid\nconcentrations will be monitored to confirm any changes in TA due to potassium\nbitartrate.<\/p>\n\n\n\n

Volatile Acidity (VA),<\/strong>\nexpressed as acetic acid equivalents in g\/L or mg\/L given its relatively\nsmaller concentration, measures the concentration of all volatile\n(steam-distillable) acids. Increasing VA levels would point to increasing\nacetic acid amounts resulting from the activity of acetic acid bacteria, which\nthrive in the presence of oxygen, or from chemical oxidation of ethanol into\nacetaldehyde then into acetic acid, which would point to excessive oxygen\ningress and exposure. My lab is not equipped to measure acetaldehyde\nconcentrations.<\/p>\n\n\n\n

pH<\/strong> will be monitored as changes\nin TA could trigger changes in pH. pH measurements are also used to determine\nthe optimum FSO2 level when needing to make adjustments at the three-month\nintervals.<\/p>\n\n\n\n

Ethanol content<\/strong>, expressed\nas a percentage of ethanol volume, or %ABV<\/strong>,\nis a measure of the amount of ethanol in wine. A decrease in %ABV can result\nfrom evaporative loss through the barrel and Flextank materials and from\nmicrobial or chemical transformations as described above.<\/p>\n\n\n\n

Free Sulfur Dioxide (FSO2)<\/strong>,\nexpressed in mg\/L, measures the concentration of molecular SO2<\/sub> and\nbisulfite ions collectively protecting wine against microbial and chemical\nspoilages. Differences in FSO2 measurements between batches could point to\ndifferences in oxygen consumption, which would mean vessels are exchanging\noxygen at different rates. As FSO2 changes can also be due to binding\nreactions, Dissolved Oxygen (DO)<\/strong>,\nexpressed in mg\/L, will also be measured.<\/p>\n\n\n\n

To understand the extent of binding, Total Sulfur Dioxide (TSO2)<\/strong>, expressed in mg\/L, will be measured to see if the oak wood from the barrel is still contributing tannins (tannins are SO2<\/sub> binders). If there is oxidative spoilage with the formation of acetaldehyde, a strong SO2<\/sub> binder, there will be a decrease in FSO2 and an increase in Bound Sulfur Dioxide (BSO2)<\/strong>. BSO2, expressed in mg\/L, is simply calculated from the difference between measured TSO2 and FSO2.<\/p>\n\n\n\n

Color evolution in reds is used to assess the age of wines. Young wines\nare characterized by a reddish, somewhat purple color. As wine ages,\npolyphenols oxidize into their brown-colored forms, known as o<\/em>-quinones, which can be seen by an\norange-hued tint at the rim, then to brownish hues as the wine ages and exceeds\nits ability to preserve red color. A number of parameters are used to gauge\ncolor evolution and to assess a potential browning problem. A very low FSO2 is\nthe first sign of impending oxidative spoilage.<\/p>\n\n\n\n

Color intensity and hue are the two very important color parameters for\nassessing reds.<\/p>\n\n\n\n

Color Intensity (IC)<\/strong>,\nexpressed in absorbance units (a.u.), is a measure of the intensity of color of\nwine and is calculated as the sum of measured spectral absorbances (A\u03bb<\/sub>)\nat wavelengths (\u03bb) of 420 nm, 520 and 620 nm. These wavelengths correspond\nto the yellow, red and purple\/blue components of color, respectively. Light-colored\nreds will have IC values between 3 and 5; medium-colored reds will have IC\nvalues between 5 and 8; and deep-colored reds will have IC values between 8 and\n12. As wine ages and oxidation reactions slowly take foot, the red component\nwill decrease and the yellow component will increase.<\/p>\n\n\n\n

Hue (H)<\/strong> is a calculation of\nthe ratio of the yellow component of color to the red component, i.e. A420<\/sub>\/A520<\/sub>.\nYoung wines will have H values below 0.8, and increasing H values, especially\nbeyond 0.8, is indicative of oxidation and increasing browning. The\npurple-bluish component visible in very young wines almost disappears as\nbrowning occurs during aging. However, oxidative reactions can give rise to blue-colored\ncompounds that are not usually visible but which will be detected by spectral\nanalysis.<\/p>\n\n\n\n

The changes in purple\/bluish color will be monitored using a Blue Index<\/strong>, calculated as the ratio of\nthe purple component of color to the red component, i.e. A620<\/sub>\/A520<\/sub>,\nwhile the loss of red color intensity and brilliance will be monitored via a Brilliance of Red (DA<\/strong>) parameter,\nexpressed as a percentage, calculated from the ratio of yellow and purple\ncomponents to (twice) the red component.<\/p>\n\n\n\n

The Total Phenol Index (TPI)<\/strong>\ncalculates an index based on the amount of polyphenols measured in wine, and\ncan point to differences in tannin reactions, and possibly extraction from oak\nwood of the barrel. Light-bodied, low-tannin wines will have TPI values between\n25 and 30; medium-bodied wines with good tannic structure will have TPI values\nbetween 30 and 50; and full-bodied, tannin-loaded wines will have TPI values\nover 50. The Folin-Ciocalteu method with absorbance readings at 750 nm is used\nto calculate TPI.<\/p>\n\n\n\n

Turbidity<\/strong>, expressed in Nephelometric Turbidity Units (NTU), is a measure of the degree of turbidity, or clarity, of a wine. Since the barrel and Flextank have different physical properties\u2014a \u201cbulging\u201d cylindrical shape on the horizontal axis versus a completely cylindrical shape on the vertical axis\u2014it is conceivable that precipitable matter can precipitate at different rates.<\/p>\n\n\n\n

Test Wine<\/strong><\/h2>\n\n\n\n

The Touriga Nacional wine used in this study has the following basic chemistry: 13.90% ABV, pH of 3.65 with a TA of 6.86 g\/L, of which 0.227 g\/L (226.9 mg\/L) is VA, FSO2 of 25.3 mg\/L, TSO2 of 54.0 mg\/L (the first sulfite addition was adjusted by 100% to account for binding), turbidity of 13.0 NTUs, residual sugar (RS) of 3.75 g\/L, IC of 5.96 with H of 0.73, and TPI of 44.10. The wine has undergone complete malic acid conversion, which was confirmed by enzymatic analysis\u2014residual malic acid concentration was below detection. Each batch was then adjusted with potassium metabisulfite (K2<\/sub>S2<\/sub>O5<\/sub>) to a FSO2 of approximately 56 mg\/L based on DO of approximately 1.80 mg\/L. The target FSO2 is based on 0.5 mg\/L of molecular SO2<\/sub> with an adjustment factor of 33% to account for FSO2 \u201clost\u201d to binding.<\/p>\n\n\n\n

Acknowledgements<\/strong><\/h2>\n\n\n\n

I would like to thank everyone in my Home Winemaking Facebook group<\/a> who have taken the time to review and comment on my testplan for this study.<\/p>\n\n\n\n

References<\/strong><\/h2>\n\n\n\n

del Alamo\u2010Sanza, M.,\nV.F. Laurie and I. Nevares. 2015. Wine evolution and spatial distribution of\noxygen during storage in high\u2010density\npolyethylene tanks. J. Sci. Food Agric. 95:1313-1320.<\/p>\n\n\n\n

Nguyen, D., L. Nicolau, S.I. Dykes and P.A. Kilmartin. 2010.\nInfluence of Microoxygenation on Reductive Sulfur Off-Odors and Color\nDevelopment in a Cabernet Sauvignon Wine. Am. J. Enol. Vitic. 61:457-464.<\/p>\n","protected":false},"excerpt":{"rendered":"

Introduction Oak barrels have long been used in winemaking. There exists a natural harmony among oak wood compounds, wine constituents, and the oxygen transferred into barrels that, in general, results… Read more »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false},"version":2}},"categories":[3,9],"tags":[126,128,4,124],"class_list":["post-1464","post","type-post","status-publish","format-standard","hentry","category-home-winemaking","category-product-reviews","tag-flextank","tag-oak-barrel","tag-winemaking","tag-winestix"],"yoast_head":"\nA Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking<\/title>\n<meta name=\"description\" content=\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking\" \/>\n<meta property=\"og:description\" content=\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel\" \/>\n<meta property=\"og:url\" content=\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\" \/>\n<meta property=\"og:site_name\" content=\"Techniques in Home Winemaking\" \/>\n<meta property=\"article:published_time\" content=\"2019-12-09T14:35:12+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-03-22T10:58:20+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/i0.wp.com\/techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=2560%2C2532&ssl=1\" \/>\n\t<meta property=\"og:image:width\" content=\"2560\" \/>\n\t<meta property=\"og:image:height\" content=\"2532\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Daniel\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Daniel\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"12 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\"},\"author\":{\"name\":\"Daniel\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692\"},\"headline\":\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel\",\"datePublished\":\"2019-12-09T14:35:12+00:00\",\"dateModified\":\"2026-03-22T10:58:20+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\"},\"wordCount\":2357,\"image\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1\",\"keywords\":[\"Flextank\",\"Oak Barrel\",\"winemaking\",\"WineStix\"],\"articleSection\":[\"Home winemaking\",\"Product Reviews\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\",\"url\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\",\"name\":\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking\",\"isPartOf\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1\",\"datePublished\":\"2019-12-09T14:35:12+00:00\",\"dateModified\":\"2026-03-22T10:58:20+00:00\",\"author\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692\"},\"description\":\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel\",\"breadcrumb\":{\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage\",\"url\":\"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1\",\"contentUrl\":\"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/#website\",\"url\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/\",\"name\":\"Techniques in Home Winemaking\",\"description\":\"A blog for those passionate about home winemaking\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692\",\"name\":\"Daniel\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g\",\"caption\":\"Daniel\"},\"sameAs\":[\"http:\/\/\"],\"url\":\"https:\/\/techniquesinhomewinemaking.com\/blog\/author\/daniel\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking","description":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/","og_locale":"en_US","og_type":"article","og_title":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking","og_description":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel","og_url":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/","og_site_name":"Techniques in Home Winemaking","article_published_time":"2019-12-09T14:35:12+00:00","article_modified_time":"2026-03-22T10:58:20+00:00","og_image":[{"width":2560,"height":2532,"url":"https:\/\/i0.wp.com\/techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=2560%2C2532&ssl=1","type":"image\/jpeg"}],"author":"Daniel","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Daniel","Est. reading time":"12 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#article","isPartOf":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/"},"author":{"name":"Daniel","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692"},"headline":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel","datePublished":"2019-12-09T14:35:12+00:00","dateModified":"2026-03-22T10:58:20+00:00","mainEntityOfPage":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/"},"wordCount":2357,"image":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage"},"thumbnailUrl":"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1","keywords":["Flextank","Oak Barrel","winemaking","WineStix"],"articleSection":["Home winemaking","Product Reviews"],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/","url":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/","name":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel - Techniques in Home Winemaking","isPartOf":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage"},"image":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage"},"thumbnailUrl":"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1","datePublished":"2019-12-09T14:35:12+00:00","dateModified":"2026-03-22T10:58:20+00:00","author":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692"},"description":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel","breadcrumb":{"@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#primaryimage","url":"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1","contentUrl":"https:\/\/i2.wp.com\/www.techniquesinhomewinemaking.com\/blog\/wp-content\/uploads\/Touriga-in-Barrel-scaled.jpg?fit=625%2C618&ssl=1"},{"@type":"BreadcrumbList","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/a-comparative-study-on-the-evolution-of-wine-aged-in-a-flextank-vs-a-two-year-old-oak-barrel\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/techniquesinhomewinemaking.com\/blog\/"},{"@type":"ListItem","position":2,"name":"A Comparative Study on the Evolution of Wine Aged in a Flextank vs. a Two-Year-Old Oak Barrel"}]},{"@type":"WebSite","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/#website","url":"https:\/\/techniquesinhomewinemaking.com\/blog\/","name":"Techniques in Home Winemaking","description":"A blog for those passionate about home winemaking","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/techniquesinhomewinemaking.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/techniquesinhomewinemaking.com\/blog\/#\/schema\/person\/a13b77da259df50c9998468e350da692","name":"Daniel","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/8f94ccf3b8f174187990c02383f6260d44aee042616c37a5897c640c214f40ec?s=96&d=mm&r=g","caption":"Daniel"},"sameAs":["http:\/\/"],"url":"https:\/\/techniquesinhomewinemaking.com\/blog\/author\/daniel\/"}]}},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p6Ubw6-nC","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/posts\/1464","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/comments?post=1464"}],"version-history":[{"count":8,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/posts\/1464\/revisions"}],"predecessor-version":[{"id":1628,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/posts\/1464\/revisions\/1628"}],"wp:attachment":[{"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/media?parent=1464"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/categories?post=1464"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/techniquesinhomewinemaking.com\/blog\/wp-json\/wp\/v2\/tags?post=1464"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}