What are two alternatives to oak casks that still add flavour and tannins?

Using staves and chips as alternatives to oak casks is a popular practice in winemaking that allows for the infusion of flavor and tannins without the need for traditional barrel aging. Staves, which are strips of wood, can be added to wine during fermentation or aging to impart complexity and character similar to that provided by oak barrels. Chips, being smaller pieces of wood, are often used for a quicker infusion of flavors, allowing winemakers to control the intensity of oak influence more precisely.

These methods can replicate the benefits of oak aging, such as adding vanillin for vanilla notes and other compounds that enhance the wine’s mouthfeel and structural integrity. Additionally, these alternatives can be more cost-effective and allow for greater flexibility in the winemaking process, as they can be easily adjusted or replaced based on the desired characteristics of the final wine.

The other options do not contribute flavor and tannins in the same way that wood does. For instance, glass and stainless steel are neutral materials that don’t impart any flavors, while plastic and ceramics also lack the capacity to provide the same complex characteristics derived from wood. Cork and composite materials primarily serve as closures and do not impact the wine's flavor profiles adversely either.