What berakhot are recited on fruit juice?
While discussing the sale of wine, our Gemara turns to a ritual question about blessings on drinks, teaching that mead made from dates or beer made from grains, as well as wine made from sediment, will all receive the basic she-hakol blessing. Others say that wine made from sediment will retain its unique blessing of borei peri ha-gafen if it retains the taste of wine.
The general principle regarding berakhot is that when a product is produced from a fruit or vegetable that is not the essence of the fruit itself, the product will lose its unique berakha – borei peri ha-etz for dates or borei peri ha-adama for the grain – and the more general blessing of she-hakol will suffice. On rare occasions, the product is considered a significant improvement over the original fruit or vegetable and a new berakha will be applied, e.g. borei peri ha-gafen for wine and ha-motzi lehem min ha-aretz for bread. Nevertheless, date mead and beer are not considered significant enough to even retain their original blessings.
Regarding the wine, it was common practice to try and maximize the volume of wine that was produced by adding water to the barrel after the wine was removed from it, so that the sediment that remained would mix with the water, which, after a time, would produce a liquid that would have the taste and smell of wine, and even some level of alcohol content.
Rava teaches that all agree that this drink is considered to be wine if three parts water are poured into the barrel and four parts are removed, since that shows clearly that the wine is a significant component of the mixture. In fact, in the time of the Gemara, wine was often sold in a concentrated form and in order to be drunk it was necessary to dilute the concentrate with three parts water to one part wine. Furthermore, Rava teaches that all agree that if the same amount of water is poured in as is removed, then it cannot possibly be considered wine.