SK46396A3 - Long-term storing method for being fermenting grape-juice - Google Patents

Abstract

Method of long-term preservation of fermented must, especially grape, by first separating the must from crushed fruits, then curled into a pressure vessel, which then, when it is expelled from it with must and / or carbon dioxide, encloses and stores, wherein left in the must before leaving in the pressure vessel to start the fermentation process.

Description

Method of long - term preservation of fermented must, especially grape must

Technical field

The invention relates to a method for the long-term preservation of fermented must, pressed from grapes or other fruit, without the use of chemical preservatives and / or heating.

BACKGROUND OF THE INVENTION

Methods for the long-term preservation of fruit juices are known, in which fruit juice is pasteurized at temperatures above 80 ° C. This destroys microorganisms, especially yeasts, which would otherwise cause various microbiological processes, especially fermentation, leading to a change in the chemical composition and nutritional properties of the must. The disadvantage of the preservation of fruit juices by heating is the change in the taste of the must and its depletion of some biologically active substances.

A variety of chemical agents are known which, when added to fruit juices, inhibit or destroy microorganisms. These are eg. o sulfur compounds, salicylic acid, formic acid and others. These substances, in order to truly allow long-term storage of the must, require dosages which are detrimental to the human body and adversely affect the taste of the must.

Grape must at the very beginning of the fermentation process is a popular drink in the wine regions. It contains a number of protective substances beneficial for the human organism. It is normally only available during the grape harvesting period, because, as a result of the spontaneous fermentation of the aplicated yeast, within a few hours, some of the sugar in the must is converted to 3 to 5% vol. ethanol, thereby losing its desired properties. This process can be slowed down by super-cooling the must to temperatures close to zero, but cannot be stopped completely. There is a known way to prepare fermented grape must for use on the market even outside the harvest season. It consists in killing the fermentation process in the must with one of the chemical agents, and before placing on the market an excess of pure yeast cultures is added to the must to restore the fermentation process. Also this process has a negative impact on the quality and nutritional value of the must and is therefore used only to a limited extent.

The invention therefore also aims to develop a simple method of preserving must, in particular grape, without the use of chemical agents, which would allow long-term storage of the must and its prompt removal from the market.

SUMMARY OF THE INVENTION

This object is achieved by a method for the long-term preservation of must, in particular grape, according to the invention, which consists in separating the must from crushed fruits first, then turning the must into a pressure vessel which gastightly closes after air has been expelled. and / or carbon dioxide and stored, whereby the fermentation process is allowed to begin in the must before closing in the pressure vessel.

It is preferred that the must be spun into a pressure vessel having a volume of 0.5 to 2.0 liters, leaving at least 5% of the vessel volume free of the must. The effect of the process according to the invention is increased if the containers are stored at a temperature between 0 and 12 ° C after closing. It is particularly advantageous if the must is turned into plastic bottles with a screw cap.

The invention makes use of the fact that the carbon dioxide pressure that develops during fermentation inhibits the propagation of yeast. E.g. Schmitthenner, F. in Vein. Rebe, 16, 1934, p. 199, that the reproduction of yeast is stopped when about 15 g of carbonic acid is dissolved in 1 liter of must. This represents a pressure of 7.85 MPa at 15 ° C, 6.32 MPa at 10 ° C and 4.81 MPa at 5 ° C. The pressure of carbon dioxide slows down the activity of yeast for a long time and excludes all aerobic microorganisms, which are very sensitive to elevated pressure, acetic bacteria, molds and the like. Useful lactic acid bacteria, which break down malic acid, are not destroyed even at a pressure of 0.81 MPa, and the degradation of acids may continue under pressure reduction.

So far, this knowledge has been used rarely in the winery to regulate the rate of fermentation processes; to influence the fermentation rate so as to ensure optimal wine quality. Essentially, this technology has made it possible to use metal tanks more and more than fermenters. The application of this principle in small volumes to grape must at the early stage of the fermentation process has led to the surprising finding that under the pressure of carbon dioxide the must stabilizes and retains its properties for up to one year.

Market exploitation of the invention by the availability of pressurized plastic carbon dioxide, having a cap on is then condensed bottles which can withstand the screwing pressure and allow easy decompression prior to the consumption of the must.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The must, pressed from a healthy, dry-grape Miiller Thurgau grape, was spun into 1.5 liter plastic bottles in the last week of September so that 10% of the bottle volume remained unfilled. The bottles were placed in an 18 ° C space with loosened screw caps for 10 hours. After this time, bubbles of carbon dioxide were clearly visible as they climbed to the level of the must and carbon dioxide escaped around the caps. Then the caps were tightened and the bottles were placed in a cellar room at a constant temperature of 10 ° C. Samples were taken every 14 days for one year. After decompression, one bottle was opened and the must and chemical properties of the must were checked. It was found that the chemical and taste properties remained almost unchanged, the sugar content in the must remained constant, the content of acids and flavorings gradually decreased, but not more than 20% over the whole 1 year.

When the bottle was decompressed and opened at room temperature, the fermentation process and the original properties of the fermented must were almost immediately restored. In such a form, the must is intended for consumption. During decompression, the must must be very foaming, so it has proven advantageous to leave the bottle part unfulfilled.

Example 2

The must pressed from the Grüner Veltliner grape was fermented in a 450 liter barrel to an optimal stage for consumption. It was then spun into 1.5 L bottles and stored as in Example 1. The monitoring and evaluation proceeded as in Example 1, with similar results.

Example 3

After pressing 100 l of the must according to Example 2, the remaining marc was poured into 50 l of water and 9 kg of sugar was added thereto. After 24 hours of leaching, the must was pressed from the mixture. The procedure was the same as in Example 2.

The invention will find application in the food industry, will enable the marketing of a popular drink with positive health effects regardless of the grape or fruit harvesting season.

Claims (4)

PATENT CLAIMS Method for the long-term preservation of fermented must, in particular grape must, characterized in that the must must first be separated from the crushed fruits, then the must must be poured into a pressure vessel which is closed after the air has been expelled by the must and / or and stored, allowing the fermentation process to start in the must before closing it in the pressure vessel. Method according to claim 1, characterized in that the must is spun into pressure vessels of 0.5 to 2.0 liters, leaving at least 5% of the volume of the vessel without the must. Method according to claim 1, characterized in that the containers are stored at 0 to 15 ° C after closing. Method according to claim 1, characterized in that the must is twisted into plastic bottles with a screw cap.