Fermentation of fruit juices

Abstract

A method of introducing yeast into a fruit juice such as grape must to be fermented is disclosed. The method comprises feeding dry yeast into a flowing stream of the fruit juice and delivering the flowing stream of fruit juice with the yeast in it to a mixer ( 10 ). The fruit juice and yeast emerging from the mixer is fed into a fermentation tank. The yeast can include nutrients selected from inactivated yeasts, yeast autolysates, yeast cell hulls, yeast extracts, amino acids, peptides, proteins, sterols, ergosterol, thiamin, biotin, pantothenic acid, niacin, riboflavin, pyridoxine, minerals and inorganic nitrogen in the form of ammonium salts.

1 . A yeast formulation which comprises dry viable yeasts mixed with one or more dry nutrients selected from inactivated yeasts, yeast autolysates, yeast hulls, yeast extracts, amino acids, peptides, proteins, sterols, ergosterols, thiamin, biotin, pantothenic acid, niacin, riboflavin, pyridoxine, minerals and inorganic nitrogen in the form of ammonium salts. 
     
     
         2 . The yeast formulation of  claim 1 , wherein the nutrients constitute 10 to 70% by weight of the yeast formulation. 
     
     
         3 . The yeast formulation of  claim 1 , comprising inactivated yeast mixed with the dry viable yeast. 
     
     
         4 . The yeast formulation of  claim 1 , wherein the viable yeast constitutes at least 20% of the dry weight of the yeast formulation. 
     
     
         5 . The yeast formulation of  claim 4 , wherein the dry viable yeast constitutes more than 60% by weight of the dry weight of the formulation. 
     
     
         6 . The yeast formulation of  claim 1 , wherein the yeast formulation is produced by mixing the viable yeast and the nutrients in the form of a cream, filtering the cream and thereafter drying a filter cake.