Natural Preservation Strategy for Green Olives: Effects of Thyme Oil-Enriched Chitosan Edible Films on Physicochemical, Microbiological, and Sensory Attributes

IF 3.7 4区农林科学 Q3 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

Journal of food protection Pub Date : 2026-01-01 Epub Date: 2025-12-13 DOI:10.1016/j.jfp.2025.100680

Pınar Çoruhlu, Ahsen Rayman Ergün, Taner Baysal

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引用次数: 0

Abstract

Edible film-coating technology is an innovative approach to help maintain food quality and inhibit microbial growth in place of synthetic preservatives. This study focused on evaluating the effects of chitosan (CS) films (2%) contained with thyme essential oil (TO) at 0.2, 0.5, and 1% on the microbiological changes, sensory, and quality attributes of green olives stored at 4 °C for 90 days. Table olive samples, which were covered with chitosan solutions containing different concentrations of thyme oil, were assessed for physicochemical (% moisture, pH, titratable acidity, color (L*, a*, b^*, and ΔE*)) and microbiological (total viable count and yeast and mold count) and sensory properties. During the storage period, moisture loss was more evident in the control group, decreasing to 53.62 ± 0.33% by day 90. In contrast, the CS and CS+TO coatings significantly reduced moisture loss. Specifically, the CS+0.2% TO, CS+0.5% TO, and CS+1% TO treatments maintained moisture levels around 57–58% at the end of storage. The overall sensory results indicated that edible coatings, particularly those containing thyme oil, effectively preserved the visual and textural quality of green olives throughout storage. However, high concentrations of thyme oil slightly reduced taste acceptability. Therefore, CS+0.2% TO and CS+0.5% TO formulations appear to offer the most balanced performance, combining effective antimicrobial protection with favorable sensory properties. The maximum reduction in total viable count (TVC) and yeast–mold was observed in the CS+1% TO group, with values of 4.36 and 3.07 log CFU/g, respectively. It has been determined that chitosan films containing thyme oil have an inhibitory effect on microbial activity. Overall, these results demonstrate the usability of edible films as synthetic preservatives and edible coating systems offer promising potential for preserving both the safety and quality of table olives, while also supporting consumer acceptance.

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绿橄榄的天然保存策略：百里香油富集壳聚糖食用膜对其理化、微生物和感官特性的影响。

可食用薄膜涂层技术是一种创新的方法，以帮助保持食品质量和抑制微生物生长的合成防腐剂的地方。研究了百里香精油（TO）浓度为0.2、0.5和1%的壳聚糖（CS）膜（2%）对绿橄榄在4℃条件下保存90 d的微生物学变化、感官和品质特性的影响。用含有不同浓度百里香油的壳聚糖溶液覆盖橄榄样品，对其理化(%水分、pH值、可滴定酸度、颜色（L*、a*、b*和ΔE*）、微生物学（总活菌数、酵母和霉菌数）和感官特性进行了评估。贮藏期间，对照组水分损失更为明显，到第90天，水分损失下降至53.62±0.33%。相比之下，CS和CS+TO涂层显著降低了水分损失。具体而言，CS+0.2% TO、CS+0.5% TO和CS+1% TO处理在贮藏结束时保持了57-58%的水分水平。整体感官结果表明，可食用涂层，特别是含有百里香油的涂层，在整个储存过程中有效地保持了绿橄榄的视觉和质地质量。然而，高浓度的百里香油略微降低了味道的可接受性。因此，CS+0.2% TO和CS+0.5% TO配方似乎提供了最平衡的性能，结合了有效的抗菌保护和良好的感官性能。CS + 1% TO组总活菌数（TVC）和酵母菌数下降幅度最大，分别为4.36和3.07 log CFU/g。经测定，百里香油壳聚糖膜对微生物活性有抑制作用。总的来说，这些结果表明，可食用薄膜作为合成防腐剂和可食用涂层系统的可用性为保持食用橄榄的安全和质量提供了有希望的潜力，同时也支持消费者接受。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Journal of food protection 工程技术-生物工程与应用微生物

CiteScore

4.20

自引率

5.00%

发文量

296

审稿时长

2.5 months

期刊介绍： The Journal of Food Protection® (JFP) is an international, monthly scientific journal in the English language published by the International Association for Food Protection (IAFP). JFP publishes research and review articles on all aspects of food protection and safety. Major emphases of JFP are placed on studies dealing with: Tracking, detecting (including traditional, molecular, and real-time), inactivating, and controlling food-related hazards, including microorganisms (including antibiotic resistance), microbial (mycotoxins, seafood toxins) and non-microbial toxins (heavy metals, pesticides, veterinary drug residues, migrants from food packaging, and processing contaminants), allergens and pests (insects, rodents) in human food, pet food and animal feed throughout the food chain; Microbiological food quality and traditional/novel methods to assay microbiological food quality; Prevention of food-related hazards and food spoilage through food preservatives and thermal/non-thermal processes, including process validation; Food fermentations and food-related probiotics; Safe food handling practices during pre-harvest, harvest, post-harvest, distribution and consumption, including food safety education for retailers, foodservice, and consumers; Risk assessments for food-related hazards; Economic impact of food-related hazards, foodborne illness, food loss, food spoilage, and adulterated foods; Food fraud, food authentication, food defense, and foodborne disease outbreak investigations.