Abstract The present study investigated influences of ultraviolet light C (UV-C; 2 kJ m−2) irradiation and high-oxygen modified atmosphere packaging (MAP; 80 % O2, 10 % CO2 and 10 % N2) on physiological quality, microbial growth and lignification metabolism of fresh-cut carrots. After 15-d cold storage, comparing with either treatment alone, the combination of UV-C irradiation and high-oxygen MAP (abbr. UV-C + MAP) more obviously inhibited firmness, weight loss, ascorbic acid, total carotenoid and γ-aminobutyric acid declines, reduced respiration and ethylene production rates as well as delayed bacterial growth. UV-C + MAP more strongly restrained whiteness index, total phenolic, lignin and malondialdehyde increases. Furthermore, UV-C + MAP treatment more efficiently retarded lignin synthesis by suppressing phenolic metabolism-related enzyme (phenylalanine ammonialyase, PAL; polyphenoloxidase, PPO; peroxidase, POD) activities and their gene (DcPAL; DcPPO; DcPOD) expressions. Above results indicated that UV-C + MAP exhibited synergistic effects in retaining physiological quality, delayed senescence process, reducing microbial growth, alleviating lignification degree, and lessened surface whitening. Therefore, UV-C + MAP could maintain overall quality and extend shelf-life during storage of fresh-cut carrots.

中文翻译：

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紫外光照射与高氧气调包装对鲜切胡萝卜生理品质、微生物生长及木质化代谢的协同作用

摘要 本研究调查了紫外线 C（UV-C；2 kJ m-2）照射和高氧气调包装（MAP；80% O2、10% CO2 和 10% N2）对生理质量、微生物生长的影响鲜切胡萝卜的木质化代谢[J]. 冷藏15天后，与单独处理相比，UV-C照射与高氧MAP（简称UV-C+MAP）联合对紧实度、失重、抗坏血酸、总类胡萝卜素和γ-氨基丁酸下降、呼吸和乙烯生成率降低以及细菌生长延迟。UV-C + MAP 更强烈地抑制白度指数，总酚、木质素和丙二醛增加。此外，UV-C + MAP 处理通过抑制酚类代谢相关酶（苯丙氨酸解氨酶，PAL；多酚氧化酶，PPO；过氧化物酶，POD）活性及其基因（DcPAL；DcPPO；DcPOD）表达，更有效地延缓木质素合成。以上结果表明UV-C+MAP在保持生理品质、延缓衰老过程、减少微生物生长、减轻木质化程度和减少表面白化方面具有协同作用。因此，UV-C + MAP 可以在鲜切胡萝卜的储存过程中保持整体质量并延长保质期。减少微生物生长，减轻木质化程度，减少表面变白。因此，UV-C + MAP 可以在鲜切胡萝卜的储存过程中保持整体质量并延长保质期。减少微生物生长，减轻木质化程度，减少表面变白。因此，UV-C + MAP 可以在鲜切胡萝卜的储存过程中保持整体质量并延长保质期。