A Pilot-Scale Industrial Study to Enhance Natural Fermentation of Table Olives (Negrinha de Freixo cv.) by Red LED Irradiation and Brine Recirculation
Source abstract
Abstract
For the first time, red LED irradiation was applied at pilot scale in the table olive industry to evaluate its influence on Negrinha de Freixo cultivar natural fermentation. Physicochemical parameters, microbial dynamics, and sensory attributes were evaluated between 60 and 95 days, with two irradiation periods (60–70 and 85–95 days). Three conditions were examined: control-static, pumping-brine recirculation, and LED-brine recirculation + red light exposure. Color or texture was not affected. The lowest pH values were consistently observed in the LED-treated samples. Total phenolic compounds in olives showed a slight decrease from 60 to day 95; however, significant differences were only detected between the pumping treatment and the other two conditions. At the end of the first LED irradiation period, a growth of lactic acid bacteria and aerobic mesophilic bacteria was observed in the order of log 1.0 CFU/mL in the brine, and the yeast count (log 1.4 CFU/g) and LAB (log 1.2 CFU/g) in the olives relative to the control, while the second irradiation period did not show a significant effect. Sensory analysis revealed that LED- irradiated olives exhibited the highest hardness (5.6) values, whereas control samples presented the highest perception of putrid defect. Overall, the results demonstrate that red LED photostimulation may be promising for application in the table olive industry.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Edible Oils Quality and Analysis · Listeria monocytogenes in Food Safety · Date Palm Research Studies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
CIMO, Associate Laboratory for Sustainability and Technology in Mountain Regions, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal
MORE-Laboratório Colaborativo Montanhas de Investigação-Associação, 5300-358 Bragança, Portugal
LOKI, Unipessoal Lda, 3750-753 Águeda, Portugal
Adega Cooperativa de Freixo de Espada à Cinta, 5180-103 Freixo de Espada à Cinta, Portugal
Funding
COMPETE 2030, co-financed by FEDER
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