METHOD OF PRODUCTION OF FRUIT VINEGAR Russian patent published in 2003 - IPC

FIELD: wine-making and alcohol industry. SUBSTANCE: invention relates to production of vinegar. Fermented fruit juice is clarified with bentonite taken in the amount determined by trial clarifying, kept, removed from precipitate and filtered. Clarified material is alcoholized additionally up to alcohol content 7-9 vol. % and used for preparing nutrient medium where (NH₄)₂HPO₄ and MgSO₄ are added as measured 1 and 0.5 g/dm³, respectively. For intensification of acetic acid fermentation medium can be acidified with citric acid taken in the amount 1 g/dm³ and to add up to 5% of fresh juice to it. Diluted yeast pure culture as measured 20-25 mln cells/mln. cells/cm³ in mixture is added to the prepared nutrient medium with initial concentration 1.5-2.2 vol. % by alcohol and 5.5-7.5% by acid. Mixture is fed to bottom part of oxidizer through nozzle placed inside by so manner that nutrient medium feeds under film uniformly. Simultaneously in bottom and top part of oxidizer compress air is fed through distributing device under pressure 25-40 kPa to provide this pressure in oxidizer. Indicated pressure provides uniform distribution of air in nutrient medium that promotes to multiplication of acetic acid microorganisms and excludes loss of volatile aroma-forming components. Oxidation of alcohol is carried out under this pressure at temperature 30-32 C up to attainment of residual alcohol content in medium 0.2-0.3 vol. %. Then crude vinegar is removed through bottom nozzle and fresh portion of nutrient medium is fed being removal and feeding are carried out at the same pressure and at feeding air providing constant aeration. Prepared crude vinegar is treated with bentonite taken in the amount 20-30 g/dm³, kept and removed from precipitate and clarified vinegar is blended to required conditions by acetic acid, pasteurized at temperature 75-80 C for 2 min, filtered and fed for bottling. Stabilization of vinegar can be carried out by addition of sorbic acid taken in the amount 100 m/dm³ or juglone taken in the amount 0.2 mg/dm³, or after filtration sulfur dioxide can be added to vinegar in the amount 25-50 mg/dm³. Filtration is recommended to carry out through titanium filter under aerobic conditions at temperature 0-(+5) C or under anaerobic conditions at temperature 20-23 C. Production of vinegar by isobaric method can be carried out by both periodic and flow-pouring method. Proposed invention allows preparing vinegar for shorter period, with minimal energy consumptions, higher organoleptic indices and yield of ready product. EFFECT: improved preparing method. 5 cl, 6 ex