کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4362979 1301529 2013 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of pectinolytic yeast on the microbial composition and spoilage of olive fermentations
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش تغذیه
پیش نمایش صفحه اول مقاله
Effects of pectinolytic yeast on the microbial composition and spoilage of olive fermentations
چکیده انگلیسی

This study resulted in the identification of pectinolytic yeasts in directly brined Sicilian-style green olive fermentations and examination of the influence of those yeasts on the microbial composition and quality of fermented olives. Firstly, defective olives processed in Northern California from 2007 to 2008 and characterized by high levels of mesocarp tissue degradation were found to contain distinct yeast and bacterial populations according to DNA sequence-based analyses. Strains of (pectinolytic) Saccharomyces cerevisiae, Pichia manshurica, Pichia kudriavzevii, and Candida boidinii isolated from directly brined olives were then inoculated into laboratory-scale olive fermentations to quantify the effects of individual yeast strains on the olives. The pH, titratable acidity, and numbers of lactic acid bacteria (LAB) and yeasts varied between the fermentations and fermentations inoculated with P. kudriavzevii and C. boidinii promoted the development of LAB populations. Olive tissue structural integrity declined significantly within 30, 74, and 192 days after the inoculation of pectinolytic S. cerevisiae, P. manshurica and C. boidinii, respectively. In comparison, tissue integrity of olives in control fermentations remained intact although pectinolytic yeasts were present. Notably, pectinolytic yeasts were not found in fermentations inoculated with (non-pectinolytic) P. kudriavzevii and olives exposed to a 1:1 ratio of P. kudriavzevii and P. manshurica exhibited no significant tissue defects. This study showed that pectinolytic yeast are important components of directly brined green olive fermentations and damage caused by pectinolytic yeasts might be prevented by other microbial colonists of the olives.


► Fermented table olives are highly vulnerable to quality defects.
► Spoiled olives contain higher amounts and distinct species of bacteria and yeast.
► Pectinolytic Saccharomyces cerevisiae were associated with extensive olive softening.
► Yeast inoculants altered the growth of LAB in olive fermentations.
► Certain yeast might be used to control pectinolysis in plant (olive) fermentations.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Food Microbiology - Volume 33, Issue 1, February 2013, Pages 97–106
نویسندگان
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