Sweetness due to Wrocław Yeast - Yarrowia lipolytica Wratislawia

The history of this yeast began over thirty years ago in a car wash. At that time a new strain of yeast Yarrowia lipolytica was isolated from soil contaminated with oil. At the beginning the research on the micro-organisms was conducted by Prof. Maria Wojtatowicz. Later on the yeast was used as a base for three habilitation theses and three doctoral theses.

The research into the use of glycerin, a byproduct from the production of biodiesel, started in 2005. At the beginning the most significant research task was the biosynthesis of citric acid from glycerol. The research showed that glycerin could be used for the biosynthesis of erythritol – a sweetening substance used in the food industry. The strain of yeast Yarrowia lipolytica Wratislawia is used for the biosynthesis of erythritol from glycerol. This strain was obtained through mutagenizing a protoplast strain with UV light which produced an acetate mutant which does not grow on microbiological media where the source of carbon is acetic acid. It is a unique mutant which possesses interesting technological characteristics. Prof. Rymanowicz, who wanted to emphasize the unique character of it, named it Wratislawia , a name dear to his heart.

Currently nine scientific workers and four technicians as well as students writing their master’s theses are taking part in the project “GREEN CHEMISTRY” which is financed from European funds within the scope of the Operational Programme Innovative Economy 2007-2013, sub-measure 1.1.2, realized by the consortium of Universities.

* * *

Erythritol, (systematic name (2R,3S)-butane-1,2,3,4-tetraol) is an aliphatic alcohol, sugar alcohol with a molecular formula C4H10O4 m.p. 121,5°C. Soluble in water, barely soluble in alcohol, insoluble in ether.

Erythritol can be used as a sweetening substance, with the level of sweetness of about 60-75% of sucrose, low-calorie (0,2 kcal/g), and does not decay teeth. Moreover it has many technical properties not connected with sweetening, which are significant for a wide range of food products – from sweets to milk products. They involve such functions as: flavor boosting, carrying, moisture retention, stabilization, a filler and ion masking.

In 2005 the Scientific Committee on Food (SCF) approved erythritol as a food additive. It has been used in Poland since 2008.