Cobrançosa table olive fermentation as per the Portuguese traditional method, using potentially probiotic Lactiplatibacillus pentosus i106 upon alternative inoculatio strategies

• Type: Article in International Scientific Journal
• Date: 2023

Authors

F. Xavier Malcata (Author) FEUP; J. Coimbra-Gomes (Author) Other; P. J. M. reis (Author) Other; T. G. Tavares (Author) Other; A. A. Silva (Author) Other; E. Mendes (Author) Other; S. Casal (Author) Other; A. C. Macedo (Author) Other

Journal

Title: Fermentation-Basel

Vol. 9 No. 1

Initial page: 12

Publisher: MDPI

Indexing

ISI Web of Knowledge

ISI Web of Science

Scientific classification

FOS: Engineering and technology

CORDIS: Technological sciences

Associated Projects

LEPABE - Financiamento Plurianual 2020-2023 da Unidade de I&D LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

ALiCE - ALiCE - Laboratório Associado em Engenharia Química

Other information

DOI: 10.3390/fermentation9010012

Abstract (EN): Spontaneous fermentation of table olives, as per a traditional Mediterranean process, is still performed empirically; hence, final product quality is somewhat unpredictable. Our main goal was to validate an endogenous (potentially probiotic) lactic acid bacterium strain in Cobrançosa table olives as a vector for a more standardized process, further adding commercial value to the olives themselves. The traditional Portuguese fermentation process typically consists of two stages: sweetening, when olives are periodically washed with spring water to different proportions, and salting, when water is no longer changed, but salt is gradually added to the brine, up to 7–10% (w/w). Lactiplantibacillus pentosus i106 was inoculated as follows: (plan A) 2020/21 harvest, with 0, 3, 5, and 7% (w/v) NaCl, without sweetening; (plan B) 2020/21 harvest, with 5 and 7% (w/v) NaCl, during salting and sweetening; and (plan C) 2019/20 harvest, with 5% (w/v) salt, and sweetening and salting. Microbiological, physical, and biochemical evolutions were monitored for 8 months, and final nutritional and sensory features were duly assessed. Compared to the control, lactic acid bacteria (LAB) predominated over yeasts only if deliberately inoculated; however strain viability was hindered above 5% (w/w) NaCl, and LAB inhibited enterobacteria. Degradation of (bitter) oleuropein to hydroxytyrosol and verbascoside was faster upon inoculation. Color-changing olives from the 2020/21 harvest exhibited higher fat content and lower water content compared to green ones (2019/20 harvest), and different salt levels and inoculation moments produced distinct sensory properties. The best protocol was plan C, in terms of overall eating quality; hence, the addition of Lpb. pentosus i106 provides benefits as a supplementary additive (or adjunct culture), rather than a starter culture.

Type (Professor's evaluation): Scientific