Natural wine refers to wine made with minimal chemical and technological intervention, both in the growing of the grapes and the making of the wine itself. The concept is rooted in the desire to maintain the natural expression of the vineyard, the grape, and the regional climate, without the addition of synthetic chemicals in the vineyard or during the winemaking process. While there is no official or legal definition of natural wine, it generally adheres to the following principles:

1. **Organic or Biodynamic Farming**: Grapes are typically grown without the use of synthetic pesticides, herbicides, fungicides, or fertilizers. Many natural wine producers adhere to organic or biodynamic farming practices, though not all are certified.

2. **Handpicked Grapes**: Grapes are often handpicked to ensure the selection of the best fruit and to prevent damage that might occur with mechanical harvesting.

3. **Minimal Intervention**: The winemaking process involves minimal intervention. This means natural fermentation with indigenous yeasts (those naturally present on the grapes or in the winery), rather than the addition of commercial yeasts. It also generally excludes the use of additives such as sulfites (though minimal amounts might be added at bottling for stability), enzymes, acid adjustments, and other common winemaking practices designed to standardize and stabilize wines.

4. **No Fining or Filtration**: Natural wines are often not fined or filtered, processes that can remove natural characteristics and textures from the wine. As a result, they might appear cloudier than conventional wines.

5. **Low to No Added Sulfites**: While sulfites are naturally occurring compounds that can act as preservatives, natural winemakers strive to minimize their addition. Some add minimal sulfites at bottling for stability, but the levels are typically much lower than in conventional wines.

Because of the lack of intervention, natural wines can offer a unique, sometimes variable expression of the specific grape variety and terroir. They may also have different flavors or characteristics than wines made using more conventional methods, including a broader range of textures and flavors.

It's important to note that the term "natural wine" can be somewhat controversial and is subject to interpretation, as there is no universally accepted standard. The lack of formal certification means that the term can be used with considerable latitude, and practices may vary significantly from one producer to another.