**The E**ff**ect of Non-***Saccharomyces* **and** *Saccharomyces* **Non-***Cerevisiae* **Yeasts on Ethanol and Glycerol Levels in Wine**

#### **Nedret Neslihan Ivit 1,2, Rocco Longo 3 and Belinda Kemp 4,5,\***


Received: 21 May 2020; Accepted: 28 July 2020; Published: 30 July 2020

**Abstract:** Non-*Saccharomyces* and *Saccharomyces* non-*cerevisiae* studies have increased in recent years due to an interest in uninoculated fermentations, consumer preferences, wine technology, and the effect of climate change on the chemical composition of grapes, juice, and wine. The use of these yeasts to reduce alcohol levels in wines has garnered the attention of researchers and winemakers alike. This review critically analyses recent studies concerning the impact of non-*Saccharomyces* and *Saccharomyces* non-*cerevisiae* on two important parameters in wine: ethanol and glycerol. The influence they have in sequential, co-fermentations, and solo fermentations on ethanol and glycerol content is examined. This review highlights the need for further studies concerning inoculum rates, aeration techniques (amount and flow rate), and the length of time before *Saccharomyces cerevisiae* sequential inoculation occurs. Challenges include the application of such sequential inoculations in commercial wineries during harvest time.

**Keywords:** non-*Saccharomyces*; *Saccharomyces* non-*cerevisiae*; yeast; wine; ethanol; glycerol
