Improving the quality of different fresh-cut fruits by adding natural substances was studied. "Fuji" apples, "Flor de Invierno" pears, and "Piel de Sapo" melons were treated with calcium lactate, N-acetyl-L-cysteine, glutathione, and malic acid and stored for 4 wk at 4 degrees C. Instrumental texture ( penetration), microstructure ( light microscopy), acidity, soluble solids, color, pectinmethylesterase activity, and microflora were studied. The results showed that the combined treatment reinforced the cell walls strengthening the structure and texture of these fruits and maintained the L degrees and a degrees values throughout 4 wk of storage at 4 degrees C. The combination of additives provided low microbial counts in apples until the 4th week and in melons until the 2nd week. So, this combined treatment could be used to extend the shelf life of some fresh-cut fruits while preserving their quality.