Understanding Fruit Ripening: A Scientific Overview

1. Ripening Defined: Ripening is a natural process where fruits become sweeter, softer, and more palatable due to biochemical changes after reaching maturity.
2. Ethylene’s Role: The gaseous plant hormone ethylene triggers ripening by initiating metabolic processes in fruits, produced naturally by growing plant tissues.
3. Climacteric vs. Non-Climacteric: Climacteric fruits (e.g., mango, banana) ripen post-harvest with ethylene, while non-climacteric fruits (e.g., grapes, citrus) do not.
4. Enzyme Action: Enzymes like amylases convert starch to sugar, pectinases soften fruit by breaking down pectin, and hydrolases alter texture and flavor.
5. Color Change: Chlorophyll degrades during ripening, and new pigments form, shifting fruit color from green to vibrant hues like red or yellow.
6. Flavor Development: Acids break down, reducing sourness, while sugars increase, and volatile compounds enhance aroma, making fruits more appealing.
7. External Triggers: Picking mature green fruit can stimulate ethylene production due to wounding, accelerating the ripening process naturally.
8. Gene Regulation: Ethylene regulates gene expression, activating enzymes that drive changes in texture, color, and taste during ripening.
9. Practical Insight: Storing unripe fruits with ripe ones in a closed space hastens ripening as ethylene from ripe fruits affects the unripe ones.
10. Scientific Relevance: Understanding ripening aids in agriculture, storage, and transport, ensuring fruit quality and reducing post-harvest losses.

Glossary

• Ethylene: A plant hormone in gas form that regulates growth and ripening processes.
• Climacteric: Fruits that continue ripening after harvest due to ethylene production.
• Non-Climacteric: Fruits that do not ripen further once picked, lacking ethylene surge.
• Enzymes: Proteins that speed up biochemical reactions, like breaking down starch or pectin.
• Pectin: A structural carbohydrate in fruit cell walls, degraded during ripening to soften texture.

Link To The Original Article – https://www.thehindu.com/sci-tech/science/how-do-fruits-ripen/article69426640.ece