Supplementary Material for: Analysis of the Cariogenic Potential of Various Almond Milk Beverages using a Streptococcus mutans Biofilm Model in vitro

To evaluate the cariogenic properties of almond milk beverages, 6 almond milks, along with soy and whole bovine milk, were analyzed for their abilities to support <i>Streptococcus mutans </i>biofilm formation and acid production, and their capacity to buffer changes in pH. Biofilm formation by <i>S. mutans</i> was analyzed using an in vitro 96-well plate model and measured by crystal violet staining. Acid production by <i>S. mutans</i> was evaluated by a colorimetric L-lactate assay and pH measurement of bacterial cultures. Buffering capacity was assessed by a pH titration assay. Soy milk supported the most biofilm growth, while the least was observed with unsweetened almond milk (both <i>p </i>&lt; 0.001). Among almond milks, sucrose-sweetened milk led to the highest level of biofilm formation (<i>p </i>&lt; 0.001), while the least was observed with unsweetened milk (<i>p </i>&lt; 0.05). Sucrose-sweetened almond milk yielded the lowest pH (4.56 ± 0.66), followed by soy milk and bovine milk; the highest pH was with unsweetened almond milk (6.48 ± 0.5). When analyzed by pH titration, the unsweetened almond milk displayed the weakest buffering capacity while bovine milk showed the highest (<i>p </i>&lt; 0.001). These results suggest that the almond milk beverages, except those that are sweetened with sucrose, possess limited cariogenic properties, while soy milk exhibits the most cariogenic potential. As milk alternatives become increasingly popular, dentists must counsel their patients that almond milks, especially sucrose-sweetened varieties, have cariogenic potential. For patients who are lactose-intolerant or suffer from milk allergy, almond milks may be a better alternative than soy-based products.

为评估杏仁奶饮品的致龋特性，本研究选取6款杏仁奶，辅以豆奶与全脂牛乳，分析其支持变形链球菌（Streptococcus mutans）生物膜形成、产酸的能力，以及缓冲pH变化的性能。变形链球菌的生物膜形成能力采用体外96孔板模型分析，并通过结晶紫染色法定量。变形链球菌的产酸能力通过比色L-乳酸测定法与细菌培养液pH测量进行评估。缓冲能力则通过pH滴定试验进行评价。
豆奶可支持最多的生物膜生长，无糖杏仁奶的生物膜生长量最少（二者均p<0.001）。在各款杏仁奶中，蔗糖甜味款的生物膜形成水平最高（p<0.001），无糖款最低（p<0.05）。蔗糖甜味杏仁奶的pH最低（4.56±0.66），其次为豆奶与牛乳；无糖杏仁奶的pH最高（6.48±0.5）。经pH滴定试验分析，无糖杏仁奶的缓冲能力最弱，而牛乳的缓冲能力最强（p<0.001）。
上述结果表明，除蔗糖甜味款外，其余杏仁奶饮品的致龋特性有限，而豆奶的致龋潜力最强。随着奶类替代品日益普及，牙医需告知患者：杏仁奶（尤其是蔗糖甜味款）具备致龋潜力。对于乳糖不耐受或牛乳过敏人群而言，杏仁奶或为优于大豆基饮品的替代选择。