Jablonski J E, Jackson L S
U.S. Food and Drug Administration (FDA), Natl. Center for Food Safety & Technology (NCFST), 6502 S. Archer Rd., Summit-Argo, IL 60501, USA.
J Food Sci. 2008 Oct;73(8):T121-8. doi: 10.1111/j.1750-3841.2008.00911.x.
Picrotoxin is a neurotoxin found in the berries of Anamirta cocculus, a plant native to Southeast Asia. Picrotoxin has potential for being used as a biological weapon since the toxin is relatively easy to isolate and purify. Limited information exists on the stability and detection of picrotoxin added to foods before or after processing. The objective of this study was to determine the stability of picrotoxin during yogurt manufacture and storage. Direct, cup-set yogurt was produced by using methods that mimic the conditions used in full-scale production of yogurt. Milk (full-fat or low-fat) was pasteurized at 85 degrees C for 30 min, and then cooled to 43 degrees C. Yogurt starter culture (thermophilic culture or thermophilic + probiotic culture) and picrotoxin (200 mug/mL milk) were added. Samples of yogurt during fermentation (5 to 6 h, 43 degrees C) and during 30 d refrigerated (4 to 6 degrees C) storage were analyzed for pH, titratable acidity, and picrototoxin levels. Regardless of starter culture used or fat content of milk, there were no significant differences in the pH and titratable acidities of the picrotoxin-spiked yogurt and the control yogurt (no added picrotoxin) during fermentation and up to 4 wk of refrigerated storage. The color or texture of the yogurt was not affected by addition of picrotoxin. Levels of picrotoxinin and picrotin (components of picrotoxin) in yogurt, as measured by LC/MS (APCI(+)/SIR) did not change significantly during fermentation and storage. A separate experiment determined that addition of picrotoxin to milk before pasteurization (85 degrees C, 30 min) did not affect picrotoxin stability. These results indicate that picrotoxin is stable in yogurt during manufacture and storage.
印防己毒素是一种神经毒素，存在于东南亚本土植物——印度防己的浆果中。由于这种毒素相对容易分离和提纯，因此有被用作生物武器的可能性。关于加工前后添加到食品中的印防己毒素的稳定性和检测方面的信息有限。本研究的目的是确定印防己毒素在酸奶制作和储存过程中的稳定性。通过采用模拟酸奶大规模生产条件的方法制作直接杯装酸奶。将全脂或低脂牛奶在85摄氏度下巴氏杀菌30分钟，然后冷却至43摄氏度。加入酸奶发酵剂（嗜热菌培养物或嗜热菌+益生菌培养物）和印防己毒素（200微克/毫升牛奶）。分析发酵期间（5至6小时，43摄氏度）以及30天冷藏（4至6摄氏度）储存期间酸奶样品的pH值、可滴定酸度和印防己毒素水平。无论使用何种发酵剂或牛奶的脂肪含量如何，在发酵期间以及冷藏储存长达4周的时间里，添加印防己毒素的酸奶和对照酸奶（未添加印防己毒素）的pH值和可滴定酸度均无显著差异。酸奶的颜色或质地不受印防己毒素添加的影响。通过LC/MS（APCI(+)/SIR）测定，酸奶中印防己诺林和印防己苦素（印防己毒素的成分）的含量在发酵和储存期间没有显著变化。一项单独的实验确定，在巴氏杀菌（85摄氏度，30分钟）之前向牛奶中添加印防己毒素不会影响印防己毒素的稳定性。这些结果表明，印防己毒素在酸奶制作和储存过程中是稳定的。
