Níveis de histamina em diferentes microvinificações

Abstract

Histamine is an organic base that develops an important physiological and metabolic function in live organisms. It is formed in normal metabolic processes and through microorganisms enzymatic activity during the fermentation or deterioration. This substance may cause problems when ingested in large amounts, when the eliminating mechanism is inefficient or when potentializers are present. The level of histamine in food varies a lot and it depends on the nature, origin, processing stages and microorganisms present. In wine, histamine has its origin in the grape itself or can be formed by the wine elaborating process, during the alcoholic and/or malolatic fermentation. The objective of this paper was to accompany the histamine level increase since the last maturation month of the grape until the wine storage period for three months. Microvinifications were done with inoculation of selected yeast (Saccharomyce cerevisiae variety bayanus and Saccharomyces cerevisiae) and without inoculation of selected yeast. In the end of the alcoholic fermentation the three treatments were divided in two groups: one was inoculated with a lactic bacteria Leuconostoc oenos and the other was not inoculated with a lactic bacteria. After the malolatic fermentation ending the wine was bottled and maintained for three months in environment temperature. The histamine after chemical derivatization with orthophthaldehyde was quantificated by High Performance Liquid Chromatography with fluorescence detection in grapes harvested during the maturation, after the grapes squashing, in the end of the alcoholic fermentation, after the malolatic fermentation and three months after the bottling. During the grape maturation, the histamine concentration increased in a higher proportion close to the harvest date. In the alcohol fermentation ending there was a reduction on the histamine level in all the three treatments. In the end of the malolatic fermentation it was noticed that the histamine concentration increased in all treatments in spite of fermentation been occurred spontaneously or by induction except to the must that realized both fermentations without the inoculation of selected organisms. In the samples collected three months after the bottling the histamine concentration found in the wine did not present a significant difference in relation to the final concentration of malolatic fermentation except to the wine that realized both fermentations without pure culture where a significant increase in the histamine concentration was found (p<0,05). It was not observed a strong correlation between the histamine levels and the chemical characteristics of pH, total acidity, volatile acidity, alcohol content and free SO2.