Countering the idea that nutritional content declines during commercial processing, food scientists have discovered volumes of anti-cancer compounds in rocket salad leaves increases postharvest.
The University of Reading research found that isothiocyanates (ITCs), which have properties that fight forms of cancer including prostate and gastrointestinal cancers, surged one week after processing rocket.
The ITC sulforaphane increased by up to three times following commercial processing and seven days of shelf life.
Dr Luke Bell, a food chemist from the University of Reading, is surprised by the findings that go against the assumption that nutrients found in rocket would “dissipate over the period of time following harvest.”
The study was funded through a Biotechnology and Biological Sciences Research Council (BBSRC) iCASE award, and partly sponsored by Bakkavor, one of the UK’s leading fresh prepared foods supplier which provided use of its facilities for growing field trials and processing the rocket leaves, while Elsoms Seeds Ltd provided seeds for experiments.
“Our study has shown that the processing actually has a potentially beneficial effect to consumers, and that rocket lovers can have confidence in the health boost a bag of rocket will give them. The biggest boost in these cancer-fighting compounds came seven days after processing, but begin to tail off after that,” Dr Bell says.
As part of the study the rocket also underwent sensory analysis to see if the cancer fighting compounds were more or less prevalent depending on the flavour profile.
“We found that there are some distinct varieties of rocket; some that are very hot, and some which are quite mild. The important thing is that the cancer-fighting compounds are prevalent in each variety, meaning that regardless of whether you like rocket mild or hot and peppery, you will still get the same potential health boost,” adds Dr Bell.
“With regular consumption of rocket and sulforaphane, consumers could potentially improve their long-term health and reduce the risk of developing other chronic diseases, such as cardiovascular disease.”
Dr Lorraine Shaw, Agronomic Development Technologist from Bakkavor said the company was keen to support research projects like this study to “further understand the role key ingredients can play in the healthy eating habits of consumers”.
Elsoms Seeds managing director, Robin Wood agrees the study provides valuable insights into ongoing research and development focusing on the properties and flavours of herbs.
“We want to understand how we can improve the taste sensation of rocket for the benefit of the consumer so we were delighted to support the project which has given us valuable information for our rocket breeding programme.”