Efficacy and permanency of ammonia treatment in reducing aflatoxin levels in corn.
Efficacy and permanency of ammonia treatment in reducing aflatoxin levels in corn.
复制标题
氨处理降低玉米黄曲霉毒素水平的功效和持久性。
DOI：
10.1080/02652039409374266
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Park,DL
中科院分区：
文献类型：
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作者：
Weng,CY;Martinez,AJ;Park,DL
研究人员将含有12500 ng/g <s:1>毒素B1（AFB1）的天然污染的黄玉米与未污染的玉米混合，以获得不同水平的AFB1（7500、6300、400、354和17 ng AFB1/g）。所有样品在不同条件下暴露于氨处理60分钟。处理变量包括氨浓度、玉米水分水平、温度和施加压力。玉米含水量由8%分别调整为12%和16%。每种湿度水平进行四种氨处理：(a)在40.45°C和55 psi条件下，1.5%和2.0%气态nh3；(b)水溶液NH4OH(2.0%为NH3)，温度121℃，压力17 psi；(c)对(a)和(b)进行顺序处理；(d)水溶液NH4OH(2.0%为NH3)，温度为25℃，压力为55 psi。在2%气态NH3处理下，含水率为12%的样品中afb1的下降幅度为52.7% ~ 67.7%，而含水率为16%的样品中afb1的下降幅度为79.4 ~ 93.1%。在高温下单独用NH4OH处理(b)或随后用气态nh3处理(c)可使afb1含量降低99%以上。25°C (d)的NH4OH处理降低afb1水平的效率较低。通过将氨处理过的玉米暴露在HC1 （pH = 2.0, 37°C， 2小时）中模拟胃酸，研究了该过程的持久性，即将失活的afb1还原为母体化合物。结果表明，黄曲霉毒素无显著逆转（可逆性小于0.05%）。上述结果表明，在高温条件下，水溶液NH4OH或气态NH3可以有效地降低玉米中afb1的含量。本研究还揭示了产品的湿度和保温温度是影响氨化去黄曲霉毒素效果的关键因素。
Naturally contaminated yellow corn containing 12500 ng/g of aîatoxin B1(AFB1) was ground and blended with non‐contaminated corn to obtain various levels of AFB1(7500, 6300, 400, 354, and 17 ng AFB1/g). All samples were exposed to ammonia treatment under various conditions for 60 min. Treatment variables included ammonia concentration, moisture level of the corn, temperature, and pressure applied. The moisture content of the corn (8%) was adjusted to 12% and 16%, respectively. Four ammonia treatments were conducted for each moisture level: (a) 1.5% and 2.0% gaseous NH3at 40.45°C and 55 psi; (b) aqueous NH4OH (2.0% as NH3) at 121°C and 17 psi; (c) sequential treatment of (a) and (b); and (d) aqueous NH4OH (2.0% as NH3) at 25°C and 55 psi. For the treatment with 2% gaseous NH3, the reduction in levels of AFB1in samples containing 12% moisture ranged from 52·7 to 67·7%, while in samples containing 16% moisture, the reduction ranged from 79.4 to 93.1%. Treatment with NH4OH alone at elevated temperatures (b) or following gaseous NH3treatment (c) resulted in a reduction of the AFB1content by greater than 99%. Treatment with NH4OH at 25°C (d) showed a lower efficiency in reducing AFB1levels. The permanency of the process, i.e. reversion of inactivated AFB1to the parent compound, was studied by exposing the ammonia‐treated corn to HC1 (pH = 2.0 at 37°C for 2 h) to simulate stomach acidity. The results showed no significant reversion of aflatoxin (reversibility less than 0.05%). These findings suggest that at high temperature aqueous NH4OH or gaseous NH3 can be used effectively to reduce AFB1in corn. The present study also revealed that the moisture level of the product and holding temperature were the crucial factors that influenced the efficacy of aflatoxin decontamination by ammoniation.