Cell Wall Stability of Fresh-Cut Fuji Apples Treated with Calcium Lactate

ABSTRACT:  This article studies the effect of calcium lactate on the structure (using low-temperature scanning electron microscopy, transmission electron microscopy, and light microscopy), texture (penetration test), pectinmethylesterase activity (titration of free carboxylic groups released by the enzyme), and polygalacturonase activity (viscosimetry) on fresh-cut Fuji apples stored for 3 wk at 4 °C. The results show that calcium lactate strengthens the structure of fresh-cut Fuji apple cell walls and counteracts the increased activity of both the pectinmethylesterase and polygalacturonase enzymes. Therefore, it is advisable to treat the product with calcium lactate to improve its structural stability. At a macroscopic level, this calcium treatment maintains the texture for at least 3 wk of storage at 4 °C.