Stimulating effect of sorbitol and xylitol on germination and growth of some xerophilic fungi

PATRIARCA A. R.; LARUMBE A. G.; BUERA M. P.; VAAMONDE G.

INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2011 vol. 28

0168-1605

Sorbitol and xylitol are polyols often used in foods as naturally occurring sugar substitutes. They providesweet taste and reduced calories in products of intermediate moisture. This type of food is susceptible tospoilage by xerophilic molds which affect shelf life of foods and produce significant losses. The aim of thepresent work was to study the effect of glycerol, sorbitol and xylitol on the germination and growth offour xerophilic fungi at different temperatures and water activity levels. Penicillium chrysogenum, Wallemia sebi, Eurotium chevalieri and Eurotium repens were cultivated on malt extract agar with the additionof the respective polyols and aw adjusted to 0.85, 0.88, 0.90 and 0.93. Incubation was made at 25, 30 and35 C. Results of the present study demonstrated that sorbitol and xylitol affect the growth kinetics of thefour fungal species. The observed tendency was that these solutes shortened the germination times andincreased the growth rates. The effect of each solute depended on the fungal species and the aw/temperature combinations. At lower aw the influence was more evident on the germination times whilethe effect on growth rates was more pronounced at higher aw levels.