|SUGAREX INCREASES ETHANOL PRODUCTION
Date: June 15, 2007
When harvested sugarcane is left in the field for a long time even up to 3 or 4 days, microbial infection set in through the cut portion of the cane. The microbial infection results into various phases of deterioration in the cane quality such as (I ) loss of sucrose
(ii ) fermentation sets in which results in alcohol formation, lactic acid formation, polymer formation such as dextrin, oligosaccharides and the like. All these by–products of bacterial infection adversely affect the quality of the juice extracted from the cane and consequently the alcohol fermentation process whether the juice is used directly or if it is processed into sugar and the c molasses used to make the alcohol.
The quality of the source material dramatically affects the behavior of yeast cells during alcoholic fermentation. The key parameters that determine the quality and fermentation potential of the material are: sugar content, minerals, suspended solids and acidity. The available sugar will dictate the ethanol yield. The concentration of sugars is significantly reduced in stale cane. High concentrations of calcium and chlorides negatively affect the alcoholic fermentation. Poor quality cane with high levels of extraneous matter may require more lime usage in the clarification process which may result in higher levels of calcium in clarified juice or molasses. Minerals like magnesium and zinc exert a positive effect on yeast health and productivity.
Source materials is normally pasteurized or decontaminated in order to reduce the amount of microorganisms acquired during its production, transportation or storage. Microorganisms (eg wild yeast and lactic acid bacteria) are generally at very high levels in stale cane and consequently in juice, these impact negatively on the fermentation process.
The acidity of the source material is also important. Very high acidic content on cane sugar molasses or cane juice is detrimental to yeast fermentation. Bacterial activity in stale cane significantly increases the juice/molasses acidity.
The formation of dextran results in increased viscosity in the fermentation broth which has a negative impact on the fermentation process. Dextran forming bacteria significantly reduce fermentable sugars.
The availability of good quality juice/molasses depends on the efficiencies of the specific sugar refineries, on weather conditions and on harvesting techniques. These variables lead to an inconsistent supply of good quality sugar cane juice/molasses and a constant dilemma for distillers.
Our experience with Sugarex is that the application of this product on cane resulted in improve yields of alcohol per units of molasses when compared to untreated cane. Sugarex does not destroy reducing sugars but prevent sucrose from breaking down by bacterial action into fermented sugar that is not fermentable.
Therefore Sugarex is a controlling agent for the inversion of sucrose for the timely action of the yeast.
Jose E. Ferrer, Ph.D.
AGRANCO CORP. USA