Contaminated Perry in Patagonia Argentina: A Case Study

Area of Science:

• Food Microbiology
• Fermentation Science
• Oenology

Background:

• Perry, a fermented pear beverage, is gaining popularity in Argentina's Patagonian region.
• Microbiological contamination poses a significant threat to the quality and stability of craft perry.

Purpose of the Study:

• To identify and characterize spoilage yeasts in contaminated craft perry from Patagonia, Argentina.
• To evaluate the growth and spoilage potential of isolated yeasts in perry must and their resistance to antimicrobial agents.

Main Methods:

• Isolation and identification of yeasts from six contaminated perry samples.
• Assessment of yeast growth in the presence of sulfite and potassium sorbate.
• Evaluation of methanol and volatile phenol production in sterile perry must.

Main Results:

• Eighteen yeast isolates were obtained, with Brettanomyces custersianus, Brettanomyces bruxellensis, and Zygosaccharomyces parabailii identified as key contaminants.
• Zygosaccharomyces parabailii NPCC1791 demonstrated tolerance to sulfite and produced high methanol levels.
• Brettanomyces bruxellensis NPPC1792 produced methanol and undesirable volatile phenols like 4-ethylphenol and 4-ethylguaiacol.

Conclusions:

• This research provides the first report on perry spoilage yeasts in Argentina.
• Identified yeast species pose a significant risk for perry contamination, impacting aromatic and physicochemical characteristics.
• Understanding these contaminants is crucial for developing effective control strategies to prevent spoilage and minimize product loss in the emerging Argentinian perry market.