{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:59:07Z","timestamp":1787029147302,"version":"build-2736575974"},"reference-count":85,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,6,1]],"date-time":"2025-06-01T00:00:00Z","timestamp":1748736000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Romanian Ministry of Research, Innovation, and Digitalization","award":["30N\/2023"],"award-info":[{"award-number":["30N\/2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This study presents a non-invasive approach to monitoring post-harvest fruit quality by applying CO2 laser photoacoustic spectroscopy (CO2LPAS) to study the respiration of \u201cConference\u201d pears from local and commercially stored (supermarket) sources. Concentrations of ethylene (C2H4), ethanol (C2H6O), and ammonia (NH3) were continuously monitored under shelf-life conditions. Our results reveal that ethylene emission peaks earlier in supermarket pears, likely due to post-harvest treatments, while ethanol accumulates over time, indicating fermentation-related deterioration. Significantly, ammonia levels increased during the late stages of senescence, suggesting its potential role as a novel biomarker for fruit degradation. The application of CO2LPAS enabled highly sensitive, real-time detection of trace gases without damaging the fruit, offering a powerful alternative to traditional monitoring methods. Additionally, artificial intelligence (AI) models, particularly convolutional neural networks (CNNs), were explored to enhance data interpretation, enabling early detection of ripening and spoilage patterns through volatile compound profiling. This study advances our understanding of post-harvest physiological processes and proposes new strategies for improving storage and distribution practices for climacteric fruits.<\/jats:p>","DOI":"10.3390\/molecules30112431","type":"journal-article","created":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T08:34:13Z","timestamp":1748853253000},"page":"2431","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["A Synergistic Approach Using Photoacoustic Spectroscopy and AI-Based Image Analysis for Post-Harvest Quality Assessment of Conference Pears"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5880-2477","authenticated-orcid":false,"given":"Mioara","family":"Petrus","sequence":"first","affiliation":[{"name":"Laser Department, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., P.O. Box MG 36, 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3881-6956","authenticated-orcid":false,"given":"Cristina","family":"Popa","sequence":"additional","affiliation":[{"name":"Laser Department, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., P.O. Box MG 36, 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4407-0292","authenticated-orcid":false,"given":"Ana Maria","family":"Bratu","sequence":"additional","affiliation":[{"name":"Laser Department, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., P.O. Box MG 36, 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasile","family":"Bercu","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Bucharest, 405, Atomistilor Str., 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4866-2946","authenticated-orcid":false,"given":"Leonard","family":"Gebac","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Bucharest, 405, Atomistilor Str., 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-9965-6517","authenticated-orcid":false,"given":"Delia-Mihaela","family":"Mihai","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Bucharest, 405, Atomistilor Str., 077125 Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana-Cornelia","family":"Butcaru","sequence":"additional","affiliation":[{"name":"Research Center for Studies of Food Quality and Agricultural Products, University of Agronomic Sciences and Veterinary Medicine, 59, Marasti Blvd., 011464 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florin","family":"Stanica","sequence":"additional","affiliation":[{"name":"Faculty of Horticulture, University of Agronomic Sciences and Veterinary Medicine, 59, Marasti Blvd., 011464 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruxandra","family":"Gogot","sequence":"additional","affiliation":[{"name":"Faculty of Horticulture, University of Agronomic Sciences and Veterinary Medicine, 59, Marasti Blvd., 011464 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,1]]},"reference":[{"key":"ref_1","first-page":"101249","article-title":"Challenges of postharvest water loss in fruits: Mechanisms, influencing factors, and effective control strategies\u2014A comprehensive review","volume":"17","author":"Gidado","year":"2024","journal-title":"J. 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