And a sturdy wall will help preserve the crisp texture of fresh produce. But creating plants with more cellulose is not necessarily the answer, Sloan says, because the resulting hardness could be unpalatable, especially in such products as strawberries. Sloan has redirected her attention to another possible solution to keeping quality texture in produce. She is investigating the chemical structure of the plant cell membrane. Made up of proteins and fatty acids, the membrane regulates water in the cell.
Water imparts the characteristic texture or crispness to fresh produce.
If the membrane is ruptured, the cell dies. High temperatures affect the proteins in the membrane, which affect the fatty acids, making the membrane less permeable, more brittle and subject to breakage. When the membrane breaks, water in the cell is released and the vegetable becomes mushy, losing texture and consumer appeal. Sloan has documented loss of protein in carrot cell membranes. Because the ratio of fatty acid to protein controls the water in the cell, when this changes, so does the texture.