Sembajwe Lawrence Fred, Nfambi Joshua, Lugaajju Allan, Kalyesubula Robert
Department of Medical Physiology, School of Biomedical Sciences, Makerere University, Kampala, Uganda.
J Food Saf Hyg. 2021 Fall;7(4):191-201. doi: 10.18502/jfsh.v7i4.9283.
Selenium is an essential trace element that is crucial for normal functioning of human body systems and it is obtained from diet or dietary supplements. The concentration of selenium (Se) varies from soil-to-soil and therefore in various food types. We profiled the selenium concentration in the major African fresh foods and studied the effect of boiling, frying and overnight soaking on their selenium content. The foods were taken to the chemistry laboratory, processed for determining selenium concentration in the fresh foods and then subjected to the various treatments before determining their Se concentration using an atomic absorption spectrometer. Among the fresh foods studied, pumpkin seeds were found to have the highest Se concentration (109.25 ± 0.125 parts per billion (ppb)), while Irish potatoes had the lowest (16.25 ± 0.125 ppb). In most fresh foods studied, boiling and frying had the effect of reducing the Se concentration, except in yams that showed an increased concentration after frying. Overnight soaking of matooke (plantain bananas) and beans showed an effect of causing a considerable reduction in the Se concentration from 36.375 ± 0.281 ppb and 59.125 ± 0.031 ppb to 14.03 ± 0.441 ppb and 24.375 ± 0.281 ppb, respectively. Boiling and frying cause a significant reduction in Se concentration of most African fresh foods. Overnight soaking of matooke and beans caused further reduction in the selenium concentration of the fresh foods. This implies that people who pre-soak their food before cooking it are likely to lose more selenium than those who do not soak and may be more likely to suffer from Se deficiencies.
硒是一种必需的微量元素，对人体系统的正常运作至关重要，它可从饮食或膳食补充剂中获取。土壤中硒（Se）的浓度因土壤而异，因此在各种食物类型中也有所不同。我们分析了非洲主要新鲜食物中的硒浓度，并研究了煮沸、油炸和过夜浸泡对其硒含量的影响。将这些食物送至化学实验室，处理后测定新鲜食物中的硒浓度，然后在使用原子吸收光谱仪测定其硒浓度之前进行各种处理。在所研究的新鲜食物中，发现南瓜籽的硒浓度最高（十亿分之109.25±0.125（ppb）），而爱尔兰土豆的硒浓度最低（16.25±0.125 ppb）。在大多数所研究的新鲜食物中，煮沸和油炸会降低硒浓度，但油炸后的山药中硒浓度有所增加。过夜浸泡木薯（大蕉）和豆类显示出硒浓度大幅降低的效果，分别从36.375±0.281 ppb和59.125±0.031 ppb降至14.03±0.441 ppb和24.375±0.281 ppb。煮沸和油炸会使大多数非洲新鲜食物的硒浓度显著降低。过夜浸泡木薯和豆类会使新鲜食物的硒浓度进一步降低。这意味着在烹饪前预先浸泡食物的人可能比不浸泡的人损失更多的硒，并且可能更易患硒缺乏症。
