See:
https://www.sciencedirect.com/scienc...40618221000422

"Abstract

The northern Bohemian sandstone region brings an exceptionally rich record of Mesolithic settlement, particularly in the form of fireplaces as key structures to be studied when addressing cooking and consumption practices. A large number of different fireplace structures – including kettle-shaped pits and surface or sunken fireplaces, some lined with stones – can be interpreted in terms of performing roasting, boiling, steaming or smoking procedures. The organic remains directly associated with them reveal which resources were exploited and almost certainly consumed, although in many cases they seem to have been discarded into the fire after processing. A Mesolithic inland settlement of northern Bohemia was undoubtedly economically based on the exploitation of plant and animal resources occurring in varied local forest and river environments. According to the evidence, hazelnuts were a staple component of the plant diet, probably processed using roasting hearths. Some fireplaces also yielded carbonised remains of other edible plants, such as raspberry (Rubus idaeus, Rubus sp.), elderberry (Sambucus nigra), red elderberry (Sambucus racemosa) and fat hen (Chenopodium album). The faunal vertebrate assemblages suggest a broad-spectrum economy, exploiting terrestrial mammals, birds, amphibians and fish. The molluscan record suggests the exploitation of edible land snails as well as thick-shelled river mussels. Rather than assuming a simple connection between fireplace type and the resources identified, a complex set of biases is considered and discussed."