Chopped carrot pieces are among the most universally enjoyed foods and a snacking staple – a mainstay of school lunchboxes, picnics and party platters year-round.
Now researchers from the University of Bath have uncovered the secret science of prepping the popular root veg and quantified the processes that make them curl up if left uneaten for too long.
Mechanical Engineering student Nguyen Vo-Bui carried out the research as part of his final-year studies, in the limited circumstances of Covid-19 lockdowns of 2021.
Without access to labs, Nguyen aimed to identify the geometrical and environmental factors which have the most influence on carrots’ longevity. Working in his kitchen, he characterised, analytically modelled and verified the ageing of over 100 Lancashire Nantes carrot halves, cut lengthways, using finite-element (FE) models normally used in structural engineering.
The research team concluded that residual stresses and dehydration were the two key factors behind the curling behaviour. The starchy outer layer of the carrot (the cortex) is stiffer than the soft central vein (also known as the vascular cylinder). When cut lengthwise, the two carrot halves curl because the difference in stress becomes unbalanced. Dehydration leads to further loss of stiffness, further driving the curling effect.
Their recommendations to manufacturers include handling carrots in cold, moist, airtight and humidity-controlled environments to protect their natural properties and increase their edible life span.
They say the study provides a methodology to predict the deformation of cut root vegetables, adding that the procedure is likely to apply to other plant structures. The study gives food producers a new mathematical tool that could be applied to the design of packaging and food handling processes, potentially reducing food waste.
One of the world’s top crops by market value, carrots are known for their high production efficiency – but despite this, wastage is high. Around 25-30% of this occurs prior to processing and packaging – due to deformities, mechanical damage or infected sections. Fresh cut and minimally processed carrots are a convenient ready-to-use ingredient that make possible the use of carrots that might otherwise be discarded, reducing food waste.
Dr Elise Pegg, a senior lecturer in Bath’s Department of Mechanical Engineering, is one of the research paper authors and oversaw the study. She said: “We have mathematically represented the curl of a cut carrot over time, and showed the factors that contribute to curling.
“Our motivation was to look for ways to improve the sustainability of carrot processing and make them as long-lasting as possible. We have produced a methodology that a food producer could use to change their processes, reducing food waste and making packaging and transportation more efficient. Understanding the bending behaviour in such systems can help us to design and manufacture products with higher durability.
Click here to read more eurekalert.org
Photo Credit: gettyimages-zbynek-pospisil
Categories: North Dakota, Crops, Fruits and Vegetables