Article

Chemical and microbial changes during the natural fermentation of strawberry tree (Arbutus unedo L.) fruits

Journal of Food Biochemistry (Impact Factor: 0.76). 01/2007; 31:715-725. DOI:10.1111/j.1745-4514.2007.00138.x

ABSTRACT Aguardente de medronho is the name given in Portugal to a spirit made
from the fermented fruit of Arbutus unedo (strawberry tree), a plant grown
in the Mediterranean region. In order to gain a better understanding of the
fermentation process, as it is performed in the farms, a natural fermentation
with wild microbiota was carried out during 36 days, and some physicochemical
and microbiological parameters were studied. The microbial parameters
analyzed were total viable, lactic and acetic acids bacteria, and yeast counts.
The physicochemical parameters monitored were sugars, minerals, ethanol,
organic acids and pH. Yeasts were the main responsible for the fermentation
of the fruits, as the lactic and acetic acids bacteria are absent. As the fermentation
progressed, the sugars increased during the first 2 days and gradually
decreased along the fermentation period. Maintaining the good quality of the
product could contribute to the preservation and valorization of traditional
resources that are of great importance to prevent their disappearance.

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