Valerga Lucia, González Roxana E, Pérez María B, Concellón Analía, Cavagnaro Pablo F
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires CP1425, Argentina.
Instituto Nacional de Tecnología Agropecuaria (INTA) Estación Experimental Agropecuaria La Consulta, La Consulta, San Carlos, Mendoza M5567, Argentina.
Plants (Basel). 2023 Mar 13;12(6):1297. doi: 10.3390/plants12061297.
Fresh-cut produce have become widely popular, increasing vegetable consumption in many parts of the word. However, they are more perishable than unprocessed fresh vegetables, requiring cold storage to preserve their quality and palatability. In addition to cold storage, UV radiation has been used experimentally to try to increase nutritional quality and postharvest shelf life, revealing increased antioxidant levels in some fruits and vegetables, including orange carrots. Carrot is one of the main whole and fresh-cut vegetables worldwide. In addition to orange carrots, other root color phenotypes (e.g., purple, yellow, red) are becoming increasingly popular in some markets. The effect of the UV radiation and cold storage has not been explored in these root phenotypes. This study investigated the effect of postharvest UV-C radiation in whole and fresh-cut (sliced and shredded) roots of two purple, one yellow, and one orange-rooted cultivar, with regard to changes in concentration of total phenolics (TP) and hydroxycinnamic acids (HA), chlorogenic acid (CGA), total and individual anthocyanins, antioxidant capacity (by DPPH and ABTS), and superficial color appearance, monitoring such changes during cold storage. Results revealed that the UV-C radiation, the fresh-cut processing, and the cold storage influenced the content of antioxidant compounds and activities to varying extents, depending on the carrot cultivar, the degree of processing, and the phytochemical compound analyzed. UV-C radiation increased antioxidant capacity up to 2.1, 3.8, 2.5-folds; TP up to 2.0, 2.2, and 2.1-folds; and CGA up to 3.2, 6.6, and 2.5-folds, relative to UV-C untreated controls, for orange, yellow, and purple carrots, respectively. Anthocyanin levels were not significantly modified by the UV-C in both purple carrots evaluated. A moderate increase in tissue browning was found in some fresh-cut processed UV-C treated samples of yellow and purple but not orange roots. These data suggest variable potential for increasing functional value by UV-C radiation in different carrot root colors.
鲜切农产品广受欢迎，在世界许多地区增加了蔬菜的消费量。然而，它们比未加工的新鲜蔬菜更易腐烂，需要冷藏来保持其品质和口感。除冷藏外，紫外线辐射已被用于实验，试图提高营养品质和采后货架期，结果显示某些水果和蔬菜（包括橙色胡萝卜）中的抗氧化剂水平有所增加。胡萝卜是全球主要的完整和鲜切蔬菜之一。除了橙色胡萝卜，其他根色表型（如紫色、黄色、红色）在一些市场上也越来越受欢迎。紫外线辐射和冷藏对这些根色表型的影响尚未得到研究。本研究调查了采后紫外线-C辐射对两个紫色、一个黄色和一个橙色根品种的完整和鲜切（切片和切丝）根中总酚（TP）、羟基肉桂酸（HA）、绿原酸（CGA）、总花青素和单个花青素的浓度变化、抗氧化能力（通过DPPH和ABTS法）以及表面颜色外观的影响，并在冷藏期间监测这些变化。结果表明，紫外线-C辐射、鲜切加工和冷藏对抗氧化化合物的含量和活性有不同程度的影响，这取决于胡萝卜品种、加工程度和所分析的植物化学化合物。相对于未处理紫外线-C的对照，紫外线-C辐射使橙色、黄色和紫色胡萝卜的抗氧化能力分别提高了2.1倍、3.8倍和2.5倍；TP分别提高了2.0倍、2.2倍和2.1倍；CGA分别提高了3.2倍、6.6倍和2.5倍。在所评估的两个紫色胡萝卜中，紫外线-C对花青素水平没有显著影响。在一些经紫外线-C处理的黄色和紫色但不是橙色根的鲜切加工样品中，发现组织褐变有适度增加。这些数据表明，紫外线-C辐射在不同根色胡萝卜中增加功能价值的潜力各不相同。
