By Andi Anderson
Michigan State University Extension, in partnership with Storage Control Systems of Sparta, Michigan, has introduced innovative Starch Index Scales tailored for 13 commercial apple varieties in the region. These user-friendly scales, unveiled in 2022, aim to revolutionize the assessment of apple maturity, assisting growers and enthusiasts in gauging fruit ripeness accurately.
The Starch Index Scales, a collaboration between Randy Beaudry, Anna Wallis, and Nicole Norris, feature meticulously captured images of iodine-stained apples, encompassing a spectrum of starch values. Through two seasons of meticulous observation, apples from the selected 13 varieties were gathered, stained, and photographed, revealing varying stages of starch conversion to sugars. These scales offer a visual representation of apple ripeness, ranging from completely unripe (0) to fully ripe (8). Notably, certain varieties exhibit incomplete starch-to-sugar conversion, providing nuanced maturity insights.
This collection of Starch Index Scales not only showcases high-quality images but also provides detailed iodine testing instructions. Moreover, it includes recommended controlled atmospheric conditions based on firmness and starch index specific to each apple variety. The featured commercial varieties encompass Ambrosia, Braeburn, Empire, Evercrisp, Fuji, Granny Smith, Honeycrisp, Idared, Jonagold, Jonathan, Pink Lady, Red Delicious, and Rome.
The innovative approach of these scales assists in overcoming interpretation challenges posed by iodine stains' diverse patterns across apple varieties. They serve as a pivotal resource for growers, aiding in optimal storage decisions and ensuring apples meet desired ripeness standards.
Photo Credit: gettyimages-dionisvero
Categories: Michigan, Crops, Fruits and Vegetables