Cooled goods have a rather limited time range, especially for trucks, unless you count the fish vehicles.* This reflects reality. The same is true for milk, which has even fewer vehicles than cooled goods. Those two are the only new cargo groups introduced by the food add-on. Grain counts as bulk goods, and use the same vehicles as coal and ore, while the rest are boxed goods.
*The fishing boats and the fish carriage can carry any kind of cooled goods, but the latter is more or less outdated by the time factories producing other kinds of cooled goods appear. There is in fact a gap of several decades between the retirement of the fish carriage and the introduction of the cooling truck, in which transport of fish and meat by road is impossible. This is one of the reasons why it is an add-on, and not part of code pak64, despite being maintained together.