Technological Properties of Fruit and Vegetable Natural Colorants

Abstract

Natural colorants are important for plant protection, but they also find an application for use in the food industry, medicine due to their positive effects on the human health. The aim of this study was to determine the content of anthocyanins and carotenoids in selected kind of fruits (blueberries, strawberries, mango) and vegetables (carrot, tomato, eggplant) in fresh material and subsequently after one and two months of storage in freezer (-18 °C). We measured a significant increase of colorants in observed samples. In blueberries, the anthocyanins content increased throughout the storage period and after two months of freezing was 48.05 % higher than in the fresh material. In the case of eggplant and strawberries, the content of anthocyanins decreased below 35 % after one month of storage and after two month, these values little bit increased, but values were lower with compare to fresh material before storage. In carotenoids, we recorded the greatest increase in tomato (105.96 %) and mango (81.27 %) after freezing with compare to fresh material.
The obtained results showed that the storage of fruits and vegetables at a low temperature can have a positive impact on the content of anthocyanins and carotenoids. This action can be attributed to cellular disruption due to the freezing process and thus to better colorants extraction. Overall, freezing, as a very popular way of storing fruits and vegetables is appropriate, there is no significant loss of carotenoids and anthocyans content, on the contrary higher usability can occur.