Final answer:
The selection of vegetables for processing considers factors such as acid, sugar, and color levels. Instruments like refractometers, pH meters, and colorimeters are used to measure these factors.
Step-by-step explanation:
When selecting vegetables for processing, factors such as acid, sugar, and color levels need to be considered.
One instrument commonly used to measure these factors is a refractometer, which measures sugar content based on the refraction of light through a vegetable sample.
Another instrument that can be used is a pH meter, which measures the acidity of a vegetable sample. Color can be evaluated visually or with the help of a colorimeter, which quantifies color intensity.