Ndoti-Nembe Aude, Vu Khanh Dang, Han Jaejoon, Doucet Nicolas, Lacroix Monique
Research Laboratories in Sciences Applied to Food, Canadian Irradiation Center (CIC), INRS-Inst. Armand-Frappier, Univ. of Quebec, 531 Boulevard des Prairies, Laval, Quebec, H7V 1B7, Canada.
Dept. of Food Bioscience and Technology, Korea Univ, Seoul, 136-701, Korea.
J Food Sci. 2015 Jul;80(7):M1544-8. doi: 10.1111/1750-3841.12918. Epub 2015 Jun 3.
This study aimed at using essential oil (EO) alone or combined EO with nisin and γ-irradiation to control Salmonella Typhimurium during the refrigerated storage of mini-carrots. Peeled mini-carrots were inoculated with S. Typhimurium at a final concentration of approximately 7 log CFU/g. Inoculated samples were coated by 5 different coating solutions: (i) nisin solution at final concentration of 10(3) IU/mL; (ii) mountain savory EO solution at 0.35%; (iii) carvacrol solution at 0.35%; (iv) mountain savory EO at 0.35% plus nisin solution of 10(3) IU/mL; or (v) carvacrol at 0.35% plus nisin solution of 10(3) IU/mL. Coated mini-carrots were then irradiated at 0.5 or 1.0 kGy and compared to an unirradiated control sample. Samples were kept at 4 °C and microbial analyses were conducted at days 1, 3, 6, and 9. The results showed that mini-carrots coated by carvacrol plus nisin solution or mountain savory EO plus nisin solution in combination with irradiation at 1.0 kGy completely eliminated S. Typhimurium to under the detection limit during the storage. Thus, the combined treatments using carvacrol plus nisin or mountain savory EO plus nisin coating solution and irradiation at 1.0 kGy could be used as an effective method for controlling S. Typhimurium in mini-carrots.
This study shows the effect of using γ irradiation at low dose (1 kGy) to reduce significantly the growth of Salmonella typhimurium in mini-carrots. It also shows that combination of nisin, essential oils with γ irradiation have the best antibacterial effects against S. Typhimurium during the storage of mini-carrots. The results can be used for practical application in food industry in terms of food safety.
本研究旨在单独使用精油（EO）或联合使用精油与乳酸链球菌素及γ射线辐照，以控制小胡萝卜冷藏储存期间的鼠伤寒沙门氏菌。将去皮小胡萝卜接种鼠伤寒沙门氏菌，使其最终浓度约为7 log CFU/g。对接种后的样品用5种不同的包衣溶液进行包衣：（i）最终浓度为10³ IU/mL的乳酸链球菌素溶液；（ii）0.35%的山地香薄荷精油溶液；（iii）0.35%的香芹酚溶液；（iv）0.35%的山地香薄荷精油加10³ IU/mL的乳酸链球菌素溶液；或（v）0.35%的香芹酚加10³ IU/mL的乳酸链球菌素溶液。然后对包衣后的小胡萝卜进行0.5或1.0 kGy的辐照，并与未辐照的对照样品进行比较。样品保存在4℃，并在第1、3、6和9天进行微生物分析。结果表明，用香芹酚加乳酸链球菌素溶液或山地香薄荷精油加乳酸链球菌素溶液包衣并结合1.0 kGy辐照的小胡萝卜在储存期间能将鼠伤寒沙门氏菌完全消除至检测限以下。因此，使用香芹酚加乳酸链球菌素或山地香薄荷精油加乳酸链球菌素包衣溶液并结合1.0 kGy辐照的联合处理方法可作为控制小胡萝卜中鼠伤寒沙门氏菌的有效方法。
本研究表明低剂量（1 kGy）γ辐照对显著降低小胡萝卜中鼠伤寒沙门氏菌生长的效果。还表明在小胡萝卜储存期间，乳酸链球菌素、精油与γ辐照联合使用对鼠伤寒沙门氏菌具有最佳抗菌效果。就食品安全而言，该结果可用于食品工业中的实际应用。
