Ancient fermented food has been studied based on recipes, residue analysis, and ancient-DNA techniques and reconstructed using modern domesticated yeast. Here, we present a novel approach based on our hypothesis that enriched yeast populations in fermented beverages could have become the dominant species in storage vessels and their descendants could be isolated and studied today. We developed a pipeline of yeast isolation from clay vessels and screened for yeast cells in beverage-related and non-beverage-related ancient vessels and sediments from several archaeological sites. We found that yeast cells could be successfully isolated specifically from clay containers of fermented beverages. The findings that genotypically the isolated yeasts are similar to those found in traditional African beverages and phenotypically they grow similar to modern beer-producing yeast strongly suggest that they are descendants of the original fermenting yeast. These results demonstrate that modern microorganisms can serve as a new tool in bio-archaeology research. IMPORTANCE So far, most of the study of ancient organisms has been based mainly on the analysis of ancient DNA. Here we show that it is possible to isolate and study microorganisms—yeast in this case—from ancient pottery vessels used for fermentation. We demonstrate that it is highly likely that these cells are descendants of the original yeast strains that participated in the fermentation process and were absorbed into the clay matrix of the pottery vessels. Moreover, we characterized the isolated yeast strains, their genomes, and the beer they produced. These results open new and exciting avenues in the study of domesticated microorganisms and contribute significantly to the fields of bio- and experimental archaeology that aim to reconstruct ancient artifacts and products.

Grapevines are susceptible and responsive to their surrounding environment. Factors such as climate region and terroir are known to affect polyphenolic compounds in wine and therefore, its quality. The uniqueness of the terroir in Israel is the variety of soil types and the climatic conditions, ranging from Mediterranean to arid climates. Thus, understanding the effects of climate on grapevine performance in Israel may be a test case for the effect of climate change on grapevine at other areas in the future. First, we present a preliminary survey (2012–2014) in different climate zones and terroirs, which showed that trans-resveratrol concentrations in Merlot and Shiraz were high, while those of Cabernet Sauvignon were significantly lower. A further comprehensive countrywide survey (2016) of Merlot wines from 62 vineyards (53 wineries) compared several phenolic compounds’ concentrations between five areas of different climate and terroir. Results show a connection between trans-resveratrol concentrations, variety, and terroir properties. Furthermore, we show that trans-resveratrol concentrations are strongly correlated to humidity levels at springtime, precipitation, and soil permeability. This work can be considered a glimpse into the possible alterations of wine composition in currently moderate-climate wine-growing areas.

34Ancient fermented food has been studied based on recipes, residue analysis and ancient-DNA 35 techniques and reconstructed using modern domesticated yeast. Here, we present a novel 36 approach. We hypothesize that enriched yeast populations in fermented beverages could have 37 become the dominant species in storage vessels and the descendants of these yeast could be 38 isolated and studied long after. To this end, using a pipeline of yeast isolation from clay vessels 39 developed here, we screened for yeast cells in beverage-related and non-related ancient vessels 40 and sediments, from several archeological sites. We found that yeast cells could be successfully 41 isolated specifically from clay containers of fermented beverages. Genomic analysis revealed that 42 these yeast are similar to those found in traditional African beverages. Phenotypically, they grow 43 similar to modern-beer producing yeast. Both strongly suggesting that they are descendants of 44 the original fermenting yeast. These findings provide modern microorganisms as a new tool in 45 bio-archeology. 46Importance 47 So far, most of the study of ancient organisms was based mainly on the analysis of ancient DNA. 48Here we show that it is possible to isolate and study microorganisms, yeast in this case, from 49 thousands of years old clay vessels, used for fermentation. We demonstrate that it is highly likely 50 that these cells are descendants of the original yeast strains which participated in the fermentation 51 process and were absorbed into the pottery vessels. Moreover, we characterize the isolated yeast 52 their genome and the beer they produce. These results open new and exciting avenues in the 53 study of domesticated microorganisms and contribute significantly to the fields of bio and 54 experimental -archeology that aims to reconstruct ancient artifacts and products.55 56 57 58 109 5containers. In contrast, we could not isolate any live yeast from the control vessels which were 110 filled with filtered beer, nor were yeast cells detected by electron microscopy (Fig. 1A, left panel).

In semi-arid areas, vineyards grown for winemaking are usually mildly irrigated by drip irrigation systems in a manner maintaining drought stress. This practice ensures the proper development of vegetative and reproductive organs on the one hand, and on the other, the development of high-quality grapes which can be hampered by overly abundant water application. In previous work, we have developed and demonstrated an irrigation model suitable for high-quality grape production in semi-arid areas. Here, we tackle the question of proper irrigation initiation dates—should one wait for vines to develop drought stress before the initiation of irrigation, or rather commence irrigation earlier? Our results show that vines which undergo initial irrigation late in the growing season tend to develop a lower midday stem water potential even after irrigation initiation. In addition, these vines tend to produce a lower number of bunches per vine and smaller berry size, leading to lower yields. The wine produced from the late-irrigated treatments had a higher phenolic content, primarily due to higher levels of catechin and epicatechin. Their levels increased as irrigation initiation dates were delayed, while caffeic acid levels showed an opposite trend. Late irrigation also led to higher color intensities compared to those of irrigation at earlier stages, due to higher levels of most anthocyanins. Finally, we show that the overall wine sensory score, representing its overall quality, was approximately five points higher for wines made from delayed irrigation treatments compared to wines made from early season irrigation treatments.

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