Whole berry fermentation

Hello! Could someone please recommend a good source to understand Whole Berry Fermentation (not Carbonic Maceration or Semi Carbonic Maceration)? I am confused after reading Understanding Wine Technology and don't think the explanation is clear...

Thanks!!!

  • HI Jiachen, 

    Whole berry fermentation refers to grapes that have been destemmed but not crushed, so that the individual grape berries are mostly intact when they go into the fermentor (like blueberries that you would buy at a store). If you've watched the winemaking video, there are several examples of this.

    Any time that you have whole berries, you get some carbonic maceration (a type of fermentation catalyzed by grape enzymes in the absence of oxygen), but the amount of impact this has on the wine depends both on the amount of whole berries, and how long they remain intact. In reality, many whole berries are crushed by weight once inside the fermentor. Generally speaking, whole cluster has more intact berries than whole berry fermentation, which has more intact berries than crushed fruit. Additionally, destemmed whole berries break down quickly since yeast and other enzymes can enter the grape through the puncture where the stem was attached. 

    We often use the term carbonic maceration to refer to whole cluster fermentation, which uses grapes that have not been destemmed or crushed, because these conditions will necessarily make wines whose organoleptic properties are influenced by carbonic character. Note that you will also get some influence from the stems that you do not get in whole berry fermentation. Some winemakers will try to reduce the carbonic character in whole cluster fermentation by intentionally breaking up the berries early on in the fermentation through cap management.

    I hope that you find this helpful! For further reading, check out Jancis Robinson's Oxford Companion, she does a nice job explaining these concepts. If you have more questions, please post them here. I am happy to help!