At https://eurekalert.org/pub_releases/2018-09/e-apt091218.php … a study published in the Journal of Archaeological Science suggests beer brewing existed in the Levant (and Eastern Mediterranean) 500 years prior to its earliest human evidence fron northern China. Indeed, the Natufians lived in the period prior to the Younger Dryas event and so we are talking about a time prior to the establishment of farming (and people living in one place and not moving around). Three stone mortars from a 13,000 year old Natufian burial cave complex have been analysed. It seems that at least one of them was used for brewing wheat or barley as well as food storage. Making alcohol must originally have been accidental – as a result of wild yeasts that are in the air at all times.
The Natufians were a pre-agricultural society, it is thought, a semi sedentary culture of foragers (although they appear to have encouraged certain plants and shrubs to grow and managed their environment, much like Mesolithic people in Europe (but with a bigger range of plants, fruits and nuts to play around with). They were proto-farmers – a seasonal activity. Presumably they discovered cereal seeds malted by storing them. Alcohol, it is thought, was used in rituals and ceremonies – and perhaps in wakes when people died and were interred. It is known early humans liked feasting – and funerals are even today followed by a meal of some kind (if only sandwiches and quiche). In the past we might expect it was an excuse to drink alcohol and indulge oneself in various ways – as long as it was in memory of the deceased (who took the central stage in speech and song). Beer brewing may have been an underlying motivation to cultivate cereals after the end of the Younger Dryas event (in the Fertile Crescent and Anatolia), leading to farms and a settled way of life (and eventaully towns and cities). This idea was around amongst archaeologists 60 years ago so it is nothing new. The Natufians perhaps brewed beer in 3 stages. First, the stock of wheat or barley was tuned into malt by germinating the grains in water (which was then drained and the grains dried and stored). Then the malt was mashed and heated. Finally, it was left to ferment with airborne wild yeasts.