Brazilian researchers have found that cassava starch-based edible coatings can boost shelf life in fresh strawberries from nine to 12 days.
The study ‘Effect of Antimicrobial Starch Edible Coating on Shelf-Life of Fresh Strawberries’ was recently published in the Packaging Technology and Science journal.
The research, led by Miriam Dupas Hubinger at the University of Campinas, found that cassava starch coatings could help guard against microbial spoilage without affecting taste and appearance.
Strawberries are a highly perishable fruit susceptible to spoilage due to yeast and mould growth. Methods typically used to enhance shelf life have included storage in cold modified atmospheres, but this has been said to cause an off-flavour, according to the authors of the study.
The researchers concluded that: “Cassava starch edible coatings, with or without potassium sorbate, were efficient in reducing weight loss, mechanical property loss and respiration rate of minimally processed strawberries, stored for 15 days at 5°C.”
Methodology and findings
The study compared strawberries coated with cassava starch, with and without potassium sorbate, to strawberries with no coating.
The strawberries used were minimally processed and stored at 5°C.
The researchers found cassava starch coatings worked better without potassium sorbate and could enhance shelf-life by three days when compared to the control sample.
No significant effects were noted on the colour, soluble solids, pH and titrable acidity of the coated strawberries.
Other solutions impacted taste or colour
So far scientists have struggled to find a solution to enhance shelf life in strawberries without negatively impacting on appearance, taste or colour.
Past studies have considered using a variety of coating materials, including wheat gluten, cactus mucilage and corn.
The researchers said that starch was commonly used for edible coatings although cassava starch was seldom used in the foods industry and therefore could be obtained at lower costs than other starch sources.
Cassava is produced in large quantities in tropical countries in South America and Africa.
For the full study see:
Lorena Costa Garcia, Leila Mendes Pereira, Claire I. G. deLuca Sarantópoulos and Miriam Dupas Hubinger (2011) ‘Effect of Antimicrobial Starch Edible Coating on Shelf-Life of Fresh Strawberries,’ Packag. Technol. Sci. - DOI: 10.1002/pts.987