Effects of magnesium ions on both VHG batch and continuous fruit wine fermentations

Abstract

In Poland, fruit wines or aromatized fruit wines are semi-sweet or sweet and contain approximately 15-16% (v/v) ethanol. Their production can be classified as a very high-gravity (VHG) fermentation. Magnesium has a beneficial effect on VHG fermentations as it protects the yeast cells against ethanol, osmotic and temperature stress. The effect of the magnesium concentration in an apple must, containing 32% sugars, on the fermentative parameters of batch and continuous fermentations was assessed. In the batch process, a magnesium concentration of~8.5 mg/L resulted in decreased the ethanol production in comparison to a magnesium concentration of~250, 490 and 970 mg Mg 2+ /L. The highest amount of Mg also caused a metallic taste. A continuous fermentation was carried out for 2.5 months in a four-column packed-bed fermentor. The medium contained~50, 250 and 490 mg Mg 2+ /L and the yeast was immobilized on foam glass. During the continuous fermentation, no differences at p ≤ 0.05 in terms of fermentative parameters were seen with magnesium additions. The same beginning amount of magnesium ions in the medium led to a similar use of this element, both in batch and in continuous fermentation. The more Mg 2+ that was present in the medium, the more Mg 2+ was used by the yeast. The results suggest that the minimal dose of magnesium, under the described conditions, is 50 mg/L, corresponding to the amount of Mg in the medium prepared using concentrated apple juice and tap water. This finding has industrial significance, as Polish wine companies prepare their fruit musts using tap water.

The Quality of Ciders Depends on the Must Supplementation with Mineral Salts

“…They stabilize biological membranes and are important for nucleic acids, ribosomes, polysaccharides, and lipids (stress suppressors). The resultant effects of stress on yeast cells during fermentation causes disproportionate synthesis of esters and higher alcohols [ 62 , 63 ].…”

Optimization of the Ginkgo Wine Fermentation Process and Influence of Fermentation Starter Types on the Brewing Flavor

“…As shown in Figure 2A-C, with increases in the solid-liquid ratio and sugar addition, the sensory score shows an upward trend with noticeable changes. The amount of sugar added will affect the alcohol content and flavor components of ginkgo wine [23]. The taste and aroma of wine fermented at different sugar levels will vary significantly.…”

The Trends and Prospects of Winemaking in Poland

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