Bose Sandeep, Pal Devendra, Ariya Parisa A
Department of Chemistry, McGill University, Montreal, Quebec H3A 0B8, Canada.
Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec H3A 0B9, Canada.
ACS Food Sci Technol. 2024 Apr 11;4(5):1039-1051. doi: 10.1021/acsfoodscitech.3c00561. eCollection 2024 May 17.
Little is known about the role of starchy food on climate change processes like ice nucleation. Here, we investigate the ice nucleation efficiency (INE) of eight different starchy food materials, namely, corn (CO), potato (PO), barley (BA), brown rice (BR), white rice (WR), oats (OA), wheat (WH), and sweet potato (SP), in immersion freezing mode under mixed-phase cloud conditions. Notably, among all these food materials, PO and BA exhibit the highest ice nucleation efficiency with ice nucleation temperatures as high as -4.3 °C ( ∼ -7.0 ± 0.5 °C) and -6.5 °C ( ∼ -7.2 ± 0.2 °C), respectively. We also explore the effect of environmentally relevant physicochemical conditions on ice nucleation efficiency, including different pH, temperature, UV/O/NO exposure, and various cocontaminants. The change in shape, size, surface properties, hydrophobicity, and crystallinity of materials accounted for the altered INE. The increase in shape, size, and hydrophobicity of the sample generally reduces the INE, whereas an increase in crystallinity enhances the INE of the sample under our experimental conditions. The results suggest that environmentally relevant concentrations slightly alter INE, indicating their role as catalysts in environmental matrices. The outcome of studies on the ice nucleation properties of these food-containing aerosols might help in the physicochemical understanding of other biomolecule-induced ice nucleation, which is still an underdeveloped research area.
关于淀粉类食物在诸如冰核形成等气候变化过程中的作用，人们了解甚少。在此，我们研究了八种不同淀粉类食物材料，即玉米（CO）、土豆（PO）、大麦（BA）、糙米（BR）、白米（WR）、燕麦（OA）、小麦（WH）和红薯（SP）在混合相云条件下的浸入式冷冻模式下的冰核形成效率（INE）。值得注意的是，在所有这些食物材料中，PO和BA表现出最高的冰核形成效率，其冰核形成温度分别高达-4.3°C（约-7.0±0.5°C）和-6.5°C（约-7.2±0.2°C）。我们还探讨了与环境相关的物理化学条件对冰核形成效率的影响，包括不同的pH值、温度、紫外线/臭氧/一氧化氮暴露以及各种共污染物。材料的形状、尺寸、表面性质、疏水性和结晶度的变化导致了INE的改变。在我们的实验条件下，样品形状、尺寸和疏水性的增加通常会降低INE，而结晶度的增加则会提高样品的INE。结果表明，与环境相关的浓度会轻微改变INE，表明它们在环境基质中作为催化剂的作用。对这些含食物气溶胶的冰核形成特性的研究结果可能有助于从物理化学角度理解其他生物分子诱导的冰核形成，而这仍然是一个未充分发展的研究领域。
