Bacteriophages as an Up-and-Coming Alternative to the Use of Sulfur Dioxide in Winemaking

Abstract

Certain acetic and lactic acid bacteria are major causes of quality defects in musts and wines, giving rise to defects such as a "vinegary," "sharp, like nail polish-remover" taste or preventing alcoholic and/or malolactic fermentation. Sulfur dioxide is the major tool currently used in the control of these bacteria in wine. The aim of this work was to isolate bacteriophages from musts and wine of different grape varieties that were able to eliminate lactic and acetic acid bacteria spoilages at the laboratory scale. Musts obtained from grape-berries of Vitis vinifera cv. Chardonnay and Moscatel and a red wine made with V. vinifera cv. Tintilla de Rota were used to isolate bacteriophages. Bacteriophages were obtained from each of the musts and the wine and belonged to the order Caudovirals and the family Tectivirals. They were isolated by classical virology methods and identified by electron microscopy. The host bacteria used in the study were lactic acid bacteria of the species Lactobacillus hilgardii, Lactobacillus plantarum, and Oenococcus oeni and the acetic bacteria Acetobacter aceti. A comparative study was performed by adding phage titrations and SO 2 to musts and wines, which had been previously inoculated with bacteria, to study the effectiveness of bacteriophages against bacteria. The comparative study showed that some bacteriophages were as effective as sulfur dioxide at low concentrations.

Bacteriophage ecology of fermented foods: anything new under the sun?

“…In practice, the main technic consists in collecting phages from a liquid sample obtained from the food product, or from a suspected reservoir in the manufacturing environment, and putting them into contact with a sensitive bacterial strain on a double-layer agar plate (for a detailed protocol, see [13]). It is also possible to directly enumerate phages to determine their initial level in food products [14], or to enrich them before isolation to enhance the probability of recovery [15].…”

“…However, surprisingly, no filamentous phages were retrieved from this type of products to date. Most of them are Siphoviridae and Myoviridae but Podoviridae and Tectiviridae were also isolated occasionally [14,17,20]. The hosts are usually members of the dominant species present in the corresponding food, such as Leuconostoc mesenteroides in Sauerkraut [21] or Oenococcus oeni in Wine [22].…”