The Dead Sea Scrolls, a two-thousand-year-old parchment corpus of manuscripts, thought to be the most important discovery of the 20th century including the first known copies of the Hebrew Bible, have darkened in parts to the point that the text is illegible. This motivated our research to try to understand the browning of parchment mechanisms. The scrolls cannot be analyzed by any destructive methods, so alternatives had to be sought. Here we describe a series of artificial aging experiments using modern parchment, prepared especially for our project, according to traditional methods, demonstrating how the different types of browning observed on the scrolls relate to environmental conditions as well as post finding treatments. Even the most extreme browning could be caused by prolonged exposure to water. This was in complete variance from controlled relative humidity exposure, where even elevated temperatures over a full five months caused only mild browning. We also confirm browning occurs at room temperature and within short periods when parchment is wet. We noted greater darkening of the flesh side in short term experiments, while browning was similar on both sides in conditions where water or humidity levels were maintained over a longer period. Artificial aging also confirmed the damage to the lower ends of many scrolls was likely caused by capillary actions when parchment was standing in water. That experiment also showed a dark tide-line phenomenon at the wet-dry interface, similar to that observed in paper substrates. Using analytical methods including FTIR, SEM, Light microscopy, UV–Vis and Fluorimetry we found the browning was always associated with denaturation, or loss of structure, mostly due to water and heat. This results in a flattening of the parchment structure which could be altering how light is reflected. However, in one artificial aging experiment the color was clearly seen to migrate and disperse over the parchment, after its initial formation. We believe this means the color is due to dark pigments; therefore, the main mechanism we suggest is melanoidin pigment formation due to a Maillard type reaction between amino acids and sugars or oxidized lipids, which are perhaps freed to react due to denaturation and hydrolysis. The results collected here can serve as an important step towards a full mechanistic understanding of parchment browning.

死海古卷（Dead Sea Scrolls）是一种具有2000年历史的手稿羊皮纸素材集，被认为是20世纪最重要的发现，其中包括希伯来圣经的首批已知副本，但部分内容已变暗，以至于文本是难以辨认。这激发了我们的研究尝试去了解羊皮纸机制的褐变。涡卷无法通过任何破坏性的方法进行分析，因此必须寻求替代方案。在这里，我们根据传统方法描述了一系列使用现代羊皮纸专门为我们的项目准备的人工老化实验，这些实验证明了在涡卷上观察到的不同类型的褐变与环境条件以及后期发现处理之间的关系。长时间接触水也可能导致最严重的褐变。这与受控的相对湿度暴露完全不同，在相对的相对湿度下，即使整个五个月的温度升高，也只会引起轻微的褐变。我们还确认室温和短期内会发生褐变当羊皮纸湿时。在短期实验中，我们注意到果肉一侧的变黑程度更大，而在较长时间保持水或湿度水平的情况下，两侧的褐变现象相似。人工老化还证实了羊皮纸在水中站立时毛细作用可能导致许多涡卷下端的损坏。该实验还显示了在干湿界面上的暗潮线现象，类似于在纸质基材中观察到的现象。使用包括FTIR，SEM，光学显微镜，UV-Vis和荧光法在内的分析方法，我们发现褐变总是与变性或结构损失有关，主要是由于水和热。这导致羊皮纸结构变平，这可能会改变光的反射方式。然而，在一项人工老化实验中，在最初形成羊皮纸后，可以清楚地看到颜色在羊皮纸上迁移和分散。我们认为，这意味着颜色是由于深色颜料引起的。因此，我们建议的主要机理是由于氨基酸与糖或氧化脂质之间的美拉德型反应，从而形成了黑色素色素，它们可能由于变性和水解而自由地发生反应。这里收集的结果可以作为迈向对羊皮纸褐变的全面机械理解的重要一步。可能由于变性和水解而自由反应。这里收集的结果可以作为迈向对羊皮纸褐变的全面机械理解的重要一步。可能由于变性和水解而自由反应。这里收集的结果可以作为迈向对羊皮纸褐变的全面机械理解的重要一步。