In the question What's the difference between "these" and "those"? it's said that the choice between "those" or "these" is distance (physical or perceived) from the object. But, which one would I use to refer to the subject of a previous sentence, as in the following example:
As discussed previously, there may be apples that emit light of longer wavelength. Those red apples can’t be used in grandma's apple pie, as the recipe specifically demands green apples.