The sugar (TSS) to acid ratio is a key characteristic determining the taste and texture and even the feel of fruit segments. The sugar/acid ratio contributes towards giving citrus its characteristic flavor, and also it is the indicator of commercial maturity (ripeness). At the beginning of the maturing process the fruit's sugar content is low and the acid content is high, making the fruit taste sour. However, as the "ripening" progresses the fruit's acids degrade down and the sugar content increases making the sugar to acid ratio achieve a higher value. In the USA, a minimum TSS/acid maturity ratio of between 7 to 9 percent sugar to 1 acid is typically desired for oranges and mandarins, but for grapefruit between 5 to 7 percent sugar to 1 acid is the standard for marketable produce. In tropical climates harvesting of oranges starts when the minimum TSS/acid ratios are reached and the fruit has a green-yellow color on no more than 25% of its surface. In Mediterranean climates, citrus is harvested when the correct TSS/acid ratio is obtained and the fruit is orange in color over on its entire surface. If the fruit is harvested early it is degreened in ethylene chambers.
The TSS to acids ratio is determined by simple division. For example: if the brix value is 12 and the total acid value is 1.0%, the ratio would be 12. If juice had a brix value of 12 and an acid value of 0.8%, the ratio would be 15.
Millet
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Topic: Maturity of Citrus Fruit (Read 1562 times)