Document Type



Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence



Publication Details

Journal of Food Engineering, vol.79, 2007, pp.1196-1206

Available from the publisher here


The use of calcium lactate solutions has been shown to be a healthy alternative to chlorine washing in order to maintain the shelf-life of fresh-cut products. The aim of this research was to analyse the effects of calcium lactate (15 g L−1) treatment at 25 °C and 50 °C (heat-shock) on the textural properties of sliced carrots and to compare those with the chlorine treatment (120 mg L−1) widely used in industry. Several direct and indirect markers of textural changes in carrots during storage were used: Instron textural analysis, Cryo-SEM and optical microscopic, sensory analysis, pectin methylesterase (PME) activity, calcium content and water activity. Samples treated with calcium lactate maintained texture significantly (p < 0.05) better than samples treated with chlorine throughout storage. Calcium lactate treatment produced a reduction in the water activity in sliced carrots and a higher firmness (Instron analysis) than chlorine treatment. In addition, combined use of heat-shock and calcium lactate treatment increased PME activity significantly when compared to the other treatments, results that were confirmed by sensory analysis. Cryo-SEM analyses showed that combined heat-shock and calcium lactate treatment was more effective in maintaining the turgor of cortex tissue cells and reduced the extent of lignification at cutting-edge areas. The use of calcium lactate combined with heat-shock is a promising washing method for fresh-cut carrots in order to preserve their texture and improve their nutritional value, avoiding the use of chlorine washing.



Technological Sector Research grant (2002–2006) and International Collaboration Award Scheme (ICAS) (2005–2007).