en تخصصي Special Original article Original article <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:112%"><span style="word-break:break-all"><span style="color:black"><b><span style="line-height:112%">ABSTRACT</span></b></span></span></span><br> <span style="line-height:115%"><b><span lang="PT-BR"><span style="line-height:115%">Background:</span></span></b><span lang="PT-BR"><span style="line-height:115%"> Pomelos have high economic value; however if not properly preserved, their quality deteriorates rapidly. This study aimed to determine the effect of biofilms made from chitosan, nisin, and tannin at various concentrations by evaluating pomelo quality indicators during preservation. </span></span></span><br> <span style="line-height:115%"><span style="word-break:normal"><span style="color:black"><b><span lang="PT-BR"><span style="line-height:115%">Methods: </span></span></b><span lang="PT-BR"><span style="line-height:115%">Each experimental batch was conducted on 20 </span></span><span style="line-height:115%">ripe green-skin pomelos, collected from June to September 2024 in Mekong River Delta region, Vietnam. A mixture solution was prepared from chitosan, nisin, and tannin in a ratio of 8:1:1 at different concentrations (0.5, 1.0, 1.5, 2.0, and 2.5%) for coating. P</span><span lang="PT-BR"><span style="line-height:115%">omelo quality indicators</span></span><span style="line-height:115%"><span style="letter-spacing:-.4pt">-including: spoilage rate, Total Soluble Solids, Total Acid</span></span><span lang="PT-BR"><span style="line-height:115%"> (TA)</span></span><span style="line-height:115%"><span style="letter-spacing:-.4pt">, and weight loss rate-were monitored at 15, 30, 45, 60, 75 and 90 days. </span>Statistical analysis was performed using </span><span class="fontstyle21"><span style="color:#131413"><span style="font-weight:normal"><span style="font-style:normal"><span style="line-height:115%">IBM SPSS Statistics 19 (IBM Corp., Armonk, NY, USA), based on the Tukey HSD. </span></span></span></span></span></span></span></span><br> <span style="line-height:115%"><b><span lang="PT-BR"><span style="line-height:115%">Results:</span></span></b><span lang="PT-BR"><span style="line-height:115%"> After 90 days of preservation, the additive mixture at a concentration of 1.5% maintained the best quality indicators: the lowest spoilage</span></span> <span lang="PT-BR"><span style="line-height:115%">rate of 22.20%; the highest TSS of 12.05 ^&deg;Bx; TA remained stably low value at 0.68 g/100ml; and the lowest pomelo weight loss rate of 42.95%. Coating made from chitosan, tannin, and nisin (8:1:1) at a concentration of 0.15% was found to be the most suitable for maintaining pomelo quality. At this concentration, both the weight loss and spoilage rates reached the lowest value after 90 days of ambient storage; TSS increased steadily and stabilized; and TA gradually decreased during the presrevation period.</span></span></span><br> <b><span lang="PT-BR"><span style="color:black">Conclusion: </span></span></b><span style="color:black">The study findings provide valuable reference information for food manufacturers and traders in selecting appropriate storage conditions to ensure the optimal grapefruit quality.</span><br> <br> <span style="word-break:break-all"><b>DOI:</b> 10.18502/jfqhc.12.3.19780</span></span></span></div> Citrus grandis, Chitosan, Tannins 163 170 http://jfqhc.ssu.ac.ir/browse.php?a_code=A-10-1859-1&slc_lang=en&sid=1 C.X. Thuy thuycx@huit.edu.vn 0009-0005-6219-5418 Yes Ho Chi Minh City University of Industry and Trade, 140 Le Trong Tan Street, Ho Chi Minh City, 0084, Vietnam L.T.H. Anh No Ho Chi Minh City University of Industry and Trade, 140 Le Trong Tan Street, Ho Chi Minh City, 0084, Vietnam