Also, if two values have been published for a given food both will be provided, or shown how the mean was found. Usually these values are reassuring because they are generally consistent. An example is that apples may only vary between thirty-two and forty in four separate studies. There are some instances of great variation. Porridge may be scored as low as forty two and as high as seventy five due to methods of cooking and processing.
Particle size is also important.
As the particle size decreases the glycemic index increases. Also to be considered is gelatinization. The greater the degree in starches the higher the glycemic index. Particle size and gelatinization help to explain why the GI's of bread and pasta differ so much. With an accurate Glycemic Index, one should be able to determine which foods will illicit high or low insulin responses.