Fruits and vegetables are rich sources of nutrients that contain phytochemicals (also known as bioactive compounds), which are recognised for their nutraceutical effects and health benefits. Daucus carota (cultivated carrot) rank among the top 10 vegetable crops in the world. They play a major role in human nutrition, because of their high dietary value and good storage attributes. Phytochemicals contribute to the dietary value of carrots and comprise mainly four types; namely, phenolic compounds, carotenoids, polyacetylenes, and ascorbic acid.
These chemicals aid in the risk reduction of cancer and cardiovascular diseases due to their antioxidant, anti-inflammatory, plasma lipid modification, and anti-tumour properties. Numerous factors influence the amount and type of phytochemicals present in carrots. Genotype (colour differences) plays an important role; high contents of α and β-carotene are present in orange carrots, lutein in yellow carrots, lycopene in red carrots, anthocyanins in the root of purple carrots, and phenolic compounds abound in black carrots. Carotenoids range between 3.2 mg/kg and 170 mg/kg, while vitamin C varies from 21 mg/kg to 775 mg/kg between cultivars. Growth temperatures of carrots influence the level of the sugars, carotenoids, and volatile compounds, so that growing in cool conditions results in a higher yield and quality of carrots, while higher temperatures would increase terpene synthesis, resulting in carrots with a bitter taste.
Potential Usage of Waste Products
Large quantities of carrots are annually discarded in different parts of the world because they do not meet market standards. Additionally, the carrot-processing industry (puree and juice) gives rise to a number of waste products, such as carrot peel, that can be recovered and used as a source of bioactive compounds. Thus, a series of valuable by-products, such as carotenoids, phenolic compounds, fractions of dietary fibre, and bioethanol, can be obtained from food-processing wastes and discarded carrots. In addition, carrots can be processed for the production of anthocyanin-rich concentrate for pigment industry, while the resulting pomace can be extracted to obtain high-value-added phenolic compounds that can be used as functional food ingredients.
Source: Ahmad T, Cawood M, Iqbal Q, Ariño A, Batool A, Tariq RMS, Azam M, Akhtar S. Phytochemicals in Daucus carota and Their Health Benefits—Review Article. Foods. 2019; 8(9):424.
Suggested further references:
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