Abstract
The oxalate content of the leaves and stems of green and variegated cultivars of sorrel (Rumex acetosa) were extracted and measured using HPLC chromatography. The larger, more mature leaves of both cultivars contained higher levels of total, soluble and insoluble oxalates. The stems also contained appreciable levels of oxalates. The mean soluble oxalate content of the variegated leaves was 14.7%, which was significantly higher than found in the leaves of the green-leaved cultivar (11.9%). The proportion of soluble oxalate to total oxalate in the stems ranged from 12.7% to 24.4% for both cultivars. Sorrel sprouts contained a much higher proportion of soluble oxalates than the green sorrel leaves but were similar in oxalate content to the variegated leaves. Pesto and soup made from sorrel leaves retained their characteristic sour taste despite containing much lower levels of oxalates. The levels of oxalates in sorrel leaves were high and it was recommended that the leaves should be consumed occasionally as a delicacy because of their unique taste rather than as a significant part of the diet. However, the products made from sorrel leaves were less of a problem as they contained lower levels of oxalates.
Highlights
Sorrel (Rumex acetosa) is a long-lived perennial plant belonging to the large and diverse Polygonaceae family
The lowest reported amounts of total and soluble oxalates in sorrel leaves were lower than 1.0 mg/100g wet matter (WM) [7]
The results showed that the soluble oxalate contents of both sorrel cultivars were positively correlated with leaf size
Summary
Sorrel (Rumex acetosa) is a long-lived perennial plant belonging to the large and diverse Polygonaceae family. Green and variegated sorrel varieties are grown as garden herbs or vegetables in Europe but they are widely distributed in parts of Asia [1]. Sorrel has been used in herbal medicine to treat cutaneous diseases [2] while the flowers contain phenolic compounds which have antiproliferative and tumour arresting effects [3,4]; extracts from the aerial parts of the plant show strong antiviral activity [5]. Sorrel is widely mentioned in gardening and recipe books because of its distinctive sour taste, which is attributed to its high oxalate content. Oxalates are responsible for creating desirable flavours in some foods [6]; the tartness of sorrel blends well with a variety of ingredients such as meat, cheese and milk. Sorrel sprouts and young immature leaves have a more subtle flavour and so are suitable for addition to salads and sandwiches. The more mature leaves are normally cooked and added to soups and stews and used to make sauces such as pesto
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
