Plastids are cell organelles found exclusively in plant cells that are responsible for changes in color and taste as fruits ripen. There are three types of plastids: chromoplasts which impart color to flowers and fruits through pigments like carotene, xanthophyll, and anthocyanin; chloroplasts which contain chlorophyll and perform photosynthesis; and leucoplasts which have no color and store food materials. As fruits ripen, chloroplasts change into chromoplasts and starch converts to sugar, explaining the changes in color and taste.