{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T16:22:22Z","timestamp":1791044542676,"version":"4.1.0"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T00:00:00Z","timestamp":1769990400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Biodiversity Future Center\u2014NBFC","award":["CN_00000033"],"award-info":[{"award-number":["CN_00000033"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Vinegar is a traditional fermented food of increasing industrial interest due to its nutritional, sensory, and bioactive properties. This study aimed to develop and optimize a controlled biotechnological process for vinegar production from the Algerian date cultivar Degla Beida, an abundant yet underexploited local resource. Indigenous Saccharomyces cerevisiae strains isolated from date fruits and Acetobacter sp. strains isolated from traditional date vinegar were employed as starter cultures in a two-stage submerged fermentation process, comprising alcoholic fermentation followed by acetic fermentation. Process optimization was carried out using Response Surface Methodology (RSM) based on a Central Composite Design (CCD), evaluating the effects of initial alcoholic degree (4\u201310% v\/v) and yeast extract supplementation (0.2\u20130.5 g\/L). The statistical models showed excellent fitting and predictive reliability (p &lt; 0.0001; R2 = 94.1\u201399.1%). Under optimal conditions (7% v\/v initial alcohol, 0.2 g\/L yeast extract, 30 \u00b0C, pH 5), the process yielded a maximum acetic acid concentration of 72 g\/L after 11 days, with 80% fermentation efficiency and complete ethanol depletion. The optimized vinegar exhibited enhanced bioactive properties, with a total phenolic content of 620 mg GAE\/100 mL and a DPPH radical scavenging activity of 78%, significantly higher than those of the unfermented juice. These results demonstrate the suitability of Degla Beida dates for vinegar production and highlight the potential of indigenous microbial resources for the sustainable valorization of local raw materials through controlled fermentation processes.<\/jats:p>","DOI":"10.3390\/foods15030518","type":"journal-article","created":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T15:38:12Z","timestamp":1770046692000},"page":"518","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Optimization of Biotechnological Vinegar Production from an Algerian Date Variety Using Indigenous Strains and Response Surface Methodology"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-5993-0611","authenticated-orcid":false,"given":"Kaouthar","family":"Djafri","sequence":"first","affiliation":[{"name":"Laboratory for the Protection of Ecosystems in Arid and Semi-Arid Zones, Department of Biological Sciences, Faculty of Natural and Life Sciences, Kasdi Merbah University, Ouargla 30000, Algeria"},{"name":"INRAA Experimental Station, National Institute of Agronomic Research of Algeria, Touggourt 30200, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1752-9029","authenticated-orcid":false,"given":"Toufik","family":"Chouana","sequence":"additional","affiliation":[{"name":"Laboratory for the Protection of Ecosystems in Arid and Semi-Arid Zones, Department of Biological Sciences, Faculty of Natural and Life Sciences, Kasdi Merbah University, Ouargla 30000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"El Hayfa","family":"Khemissat","sequence":"additional","affiliation":[{"name":"INRAA Experimental Station, National Institute of Agronomic Research of Algeria, Touggourt 30200, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meriem","family":"Bergouia","sequence":"additional","affiliation":[{"name":"INRAA Experimental Station, National Institute of Agronomic Research of Algeria, Touggourt 30200, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdelkader","family":"Abekhti","sequence":"additional","affiliation":[{"name":"Laboratory of Natural Saharian Resources, Department of Biological Sciences, Adrar University, Adrar 1001, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5315-3055","authenticated-orcid":false,"given":"Maria","family":"D\u2019Elia","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Salerno, 84084 Fisciano, Italy"},{"name":"National Biodiversity Future Center\u2014NBFC, 90133 Palermo, Italy"},{"name":"Dipartimento di Scienze della Terra e del Mare, University of Palermo, 90123 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0718-5450","authenticated-orcid":false,"given":"Luca","family":"Rastrelli","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Salerno, 84084 Fisciano, Italy"},{"name":"National Biodiversity Future Center\u2014NBFC, 90133 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,2]]},"reference":[{"key":"ref_1","first-page":"638","article-title":"Response Surface Methodology as an Approach for Optimization of Vinegar Fermentation Conditions Using Three Different Thermotolerant Acetic Acid Bacteria","volume":"14","author":"Kourouma","year":"2023","journal-title":"Food Nutr. 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