Resources

FAQs

What do Flexcubes do?

Flexcubes are designed to replicate the wine maturation process achieved in traditional oak barrels in the production of quality and wines. 

How do Flexcubes achieve this?

Very simple, we separate the elements of oxygen and oak. Oxygen permeable polymer Flexcubes provide the oxygen element necessary in the maturation of wine through constant and linear passive oxygenation. When combined with barrel quality oak, you get the flavours, tannins and aromas of barrels. Flexcubes are in essence deconstructed traditional oak barrels. They offer winemakers many additional advantages and overcome most of the limitations and disadvantages of oak barrels. 

What are Flexcubes made of?

Flexcubes are made of specially selected low density polymer that is 100% food grade.

What sizes (volumes) do the Flexcubes come in?

The Flexcubes come in the following nominal volumes: 1000L/265Gal, and 2000L/530Gal. 

Why is the word “nominal” used when describing the size (volume) of a Flexcube?

The walls are flexible, so expand and contract (slightly but significantly) when empty or full, so the dry volume will be smaller than the wet volume. So nominal means “approximate”. The Flexcube holds something like 20-30L more volume when full than when it is empty. 

How many Flexcubes can be safely stacked on top of each other when full?

Up to 4,000L/40 hl/1,060gal worth. That is equivalent to: 4×1,000 litre Flexcubes or 2×2,000 litre  Flexcubes. 

What are the advantages of having Flexcubes in my winery?

Flexcubes offer six main advantages:  

Quality -The highest possible wine quality, from the reliability of constant and linear passive oxygenation and the consistent high grade of BarriQ oak, guaranteeing wines with preservation of fresh fruit characters and integration with perfect oak influence.  

Control and Consistency – The winemaker has a broad range of options by combining different oxygen permeabilities, oak profiles, oak quantities and contact times. The passive oxygenation levels of Flexcubes are consistent from Flexcube-to-Flexcube and remain unchanged over time.  

Cost – Flexcubes give you a 40% saving on initial capital costs then further savings from reduced labour, handling, storage and cleaning. Ober the maturation period, you can make wine for as little as 0.47 cents per litre.   

Space - Flexcubes can be stacked to up to 4,000 litres making it possible to double the capacity of any barrel store room 

Maintenance – One 1,000 litre Flexcube is equivalent in capacity to four-and-a-third 225L traditional oak barrels but only requires the set-up, cleaning & maintenance of one. Flexcubes are easier to top up, clean and move around, with forklifts and /or pallet-acks. Cleaning uses much less water than traditional barrels.  

Environment – Flexcubes offer a much more efficient approach to oak, significantly reducing the environmental footprint of winemaking. In using BarriQ oak in the wine, all of the oak is being used, not just the inner 3-5mm layer as in traditional barrels. 

Why are Flexcubes more consistent than oak barrels?

The widely accepted  “Coopers rule” about barrel consistency says that out of every 10 ‘exactly the same’ barrels, 2 will be ‘excellent’, 6 will be ‘as expected’ and 2 will be ‘sub-par’. This inconsistency is due to random variation in oak wood quality, toasting variability and variations in Oxygen Transfer Rate due to carpentry, bung hole and stave jointing. Flexcubes don’t suffer from this.  

Can I use a Flexcube for white wine after using it for red wine?

Yes. Just clean your Flexcube with caustic soda to de-colourise the polymer. 

Should I use hot water to clean a Flexcube?

No. Hot water will distort the polymer and should never be used. Always clean your Flexcube with cold water and a 2% solution of caustic soda (sodium hydroxide) or similar. 

Can I store my Flexcubes outside?

Flexcubes are UV stabilised and when empty, can be safely stored outside. Full Flexcubes should of course be placed in a protected and preferably temperature-controlled cellar environment. Flexcubes in natural colour are UV stable, but do pass visible light. If storing wine outside or near a window, use the grey Flexcube. When storing empty Flexcubes, care must be taken to ensure they are clean and dry to promote a hygienic internal environment. There is no need for the use of SO2 in storing the Flexcube if it is stored clean & dry. 

What does the term “NBE” mean and what does it mean that a wine had “100% NBE”?

NBE stands for New Barrel Equivalent. 100% NBE gives approximately the same amount of oak extract as a 1st fill barrel, 60% NBE gives approximately the same oak as a 2nd year barrel and 40% as a 3rd year barrel.

What are the two main oenological differences between Flexcube BarriQ Oak & LBarriQ Oak?

LBarriQ comes from the same source of wood as BarriQ but it is cut thinner to provide faster extraction of oxygen and oak compounds in wine. For this reason, it offers faster extraction but at the cost of slightly less complexity and structure than BarriQ. 

Is Bisphenol A (BPA) associated with Flexcubes?

Flexcubes are BPA free. BPA has no role in the manufacture of any components of a Flexcube, so Flexcubes are free of BPA. 

Are Phthalates associated with Flexcubes?

No. This has been verified in laboratories both sensorily and by analysis and in repeated analytical tests the company has conducted.  

Does the polymer in Flexcubes leach?

Rigorous scientific testing done over years has confirmed that Flexcubes satisfy all the tests required for polymer use in contact with food applications.  Testing undertaken by RMIT over the past three years has proven that the polymer can be used with spirits up to 70% alcohol by volume and up to 70 degrees Celsius, with no evidence of leaching.

What are the choices in oxygen permeabilities available?

Flexcubes are available in three permeabilities: Low (LP) 6mg/L/yr; Medium (MP) 9mg/L/yr; and High (HP) 12mg/L/yr. 

Which permeability shall I use?

Low permeability is better suited for whites and those red varieties with low tannic and phenolic content (often Grenache responds better to LP). Medium permeability is the most versatile option, works very well with most Cabernets, Shiraz, Pinotage, Pinot Noir, and Merlot. High permeability ideal for varieties with high tannic and phenolic content where a softer finish or earlier release is beneficial. 

What Flexcube permeability shall I use to ferment & mature Chardonnay?

Because there is plenty of O2 available during ferment, the permeability of the Flexcube is of little influence during fermentation and immediately afterwards (say 1-2 months). So you can ferment in any permeability. For maturation, however, LP is highly recommended (essential). Chardonnay and other white ‘broaden’ and ‘fatten’ quite quickly in MP Flexcubes. 

What are the main cellar procedures I need to practice with my Flexcube?

Ullage– Check fill height every 4-8 weeks as thermal expansion/contraction will always occur with wine temperature changes. SO2 - Check and adjust SO2 levels as you would in a traditional barrel (a typical cellar will do this every 4-8 weeks).
Reductivity– If there are signs of reductivity in your wine, rack and return as you would in a traditional barrel. 

Do I need to top up my Flexcube?

Within 2 weeks of filling, the Flexcube might need to be topped, as the polymer walls will initially stretch. Unless the wine is undergoing primary or malolactic fermentation (when it must be vented), maintain the Flexcube completely full, the same as a traditional barrel. 

Product Information

Instructions & Warranty

Download PDF 

Space Efficiency Chart

Download PDF 

BPA Statement

Download PDF 

Phthalates Statement

Download PDF 

Product List

Download PDF 

Oak Information

BarriQ Specifications

Download PDF 

Oak Brochure

Download PDF 

Research

RMIT: Leaching and Headspace Analysis

Download PDF 

Spirit Maturation in Flexcubes

Download PDF 

Flexcube Video