The evolution of safety and other quality parameters of the Greek green table olives PDO “Prasines Elies Chalkidikis” that are prepared according to the Spanish style processing is examined systematically at the industrial scale and 12 month storage for two consecutive periods for the first time. Evolution of safety parameters (bacteria/yeasts, pH, acidity) during fermentation in brine and on olives upon storage, changes in olive color and texture during storage, and the fate of characteristic hydrophilic and hydrophobic antioxidants (oleuropein, ligstroside, and related compounds, α‐tocopherol, squalene), and sodium content are monitored using appropriate methods. Sensory scores are also provided in certain cases. Findings support that the final product is microbiologically safe and of acceptable characteristics. However, except for compliance with trade quality criteria, attention should be paid to the reduction in phenolic compounds (hydroxytyrosol, tyrosol) content and the important increase in sodium content due to fermentation and storage in brine. This prototype model study indicates loopholes in the efforts to establish table olives as a functional food. Practical Applications: Industry has to compromise legal safety and nutritional aspects with traditional processing and storage conditions that are applied in PDO table olive production, considering also intrinsic cultivar characteristics of the drupes. Policy makers, regulatory bodies, IOC, and the industry may profit from the substantiation provided by the results of this 2 years study. A systematic study of the industrial production line of the Greek green table olives PDO “Prasines Elies Chalkidikis” for two consecutive processing periods.

In this work, the effect of different treatments using selected combinations of chloride salts (NaCl, KCl, CaCl2, MgCl2) in fermentation brine to assess the safety, quality, and nutritional value of the Spanish style cv. Chalkidiki green table olives spontaneously fermented is studied. Examination of safety parameters (bacteria/yeasts, pH, acidity) and changes in olive color and texture characteristics in brines during fermentation, and in mineral content of olives upon storage up to 12 months, is conducted using appropriate methods. Sensory evaluation takes place in certain cases. Among the tested salt combinations, those of 4.08% NaCl, 2.8% KCl, 1% CaCl2, and 0.12% MgCl2 (w/v) are found to be the most effective regarding safety, color, texture, and taste. Findings support that Spanish style cv. Chalkidiki green olives can be spontaneously fermented in reduced NaCl content brine. The 50% lower NaCl content of the fermented olives compared with that in traditionally fermented ones suggests that reformulation of cv. Chalkidiki green table olives by safe intervention is feasible. Practical Applications: cv. Chalkidiki green table olives are of high importance for the Greek economy. Traditionally they are spontaneously fermented in NaCl brine (8% w/v). Partial replacement of NaCl content with other salts in such a line results in a product acceptable in terms of safety and quality characteristics. The Greek table olive industry may profit from the findings in an attempt to remodel the traditional spontaneous fermentation in green olive processing according to international dietary guidelines.

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In the current research, the potential of Spanish-style green olive processing wastewaters (lye and washing waters) exploitation toward natural β-carotene production by Blakeslea trispora was tested for the first time. Mating culture generated by the joint cultivation of the heterothallic fungal strains ATCC 14271 and 14272 in the non-sterile lye and washing waters was able to grow, achieving the phytotoxic hydroxytyrosol degradation by 57.3% and 66.8%, respectively. However, the low sugar and nitrogen content of the streams did not favor carotenogenesis. Alternatively, in the nutrient-enriched effluents, a notable quantity of β-carotene was produced, accounted for 61.2 mg/L (lye) and 64.1 mg/L (washing waters) (82–88% of total carotenoid content). Above all, enriched streams had a noteworthy stimulating effect on the β-carotene synthesis, because both the maximum β-carotene yield per volume of enriched effluents and specific β-carotene production rate were higher when compared with the respective values obtained from trials with synthetic reference medium without added effluents. Hydroxytyrosol and tyrosol showed high stability during the non-sterile process for β-carotene production by B. trispora grown in the enriched effluents. This finding strengthens the potential toward the generation of multiple high-value products, which could lower the natural β-carotene production costs.