Nutritional and taste characteristics of low-potassium lettuce developed for patients with chronic kidney diseases

SummaryDietary potassium restriction is recommended for chronic kidney disease (CKD) patients with hyperkalemia. Boiling or soaking vegetables in water is known to decrease their potassium content. However, these methods can also reduce the quantity of other nutrients. Recently, low-potassium (LK) lettuce has been developed for CKD patients with hyperkalemia. This study compared the potassium content, other nutritional values, and taste characteristics of LK lettuce with those of normal lettuce. The amounts of potassium and other nutrients in LK lettuce, normal leaf lettuce, and normal leaf lettuce that had been soaked in water were measured and compared. The taste characteristics of LK lettuce and normal leaf lettuce were evaluated for saltiness, bitterness, and overall preference. The LK lettuce contained a lower amount of potassium (−87%) than the normal leaf lettuce. There was no difference in the other nutritional contents between LK lettuce and normal leaf lettuce, except for higher sodium and lower nitrate contents in LK lettuce. Taste evaluation revealed that the LK lettuce had lower bitterness and higher saltiness than the normal leaf lettuce. The overall preference score was significantly higher for LK lettuce. The potassium content of LK lettuce was significantly lower than that of normal leaf lettuce, but the other nutritional values were very similar. The LK lettuce had a higher preference score than the normal leaf lettuce. These results indicate that the LK lettuce is useful for increasing the variety of foods in CKD patients with hyperkalemia.背景：對於血鉀過高的慢性腎病 (CKD) 患者，建議限制飲食中的鉀。用水浸泡或煮食則會降低蔬菜中的鉀含量，然而亦會同時降低其他營養素含量。最近，有專家特別為血鉀過高的 CKD 患者研發出低鉀萵苣。本研究對低鉀萵苣的鉀含量、營養與味道特徵作出調查，並與正常的萵苣作出比較。方法：研究人員分別對低鉀萵苣、正常葉萵苣、與泡水後的正常葉萵苣，測量了鉀及其他營養素含量。對於低鉀萵苣及正常葉萵苣的味道特徵，則根據鹹度、苦澀度、及整體偏好作出評估。結果：低鉀萵苣的鉀含量比正常葉萵苣低 87%，其他營養素方面，與正常葉萵苣相比，低鉀萵苣具較高的鈉及較低的硝酸鹽含量。味道評估顯示，相比於正常葉萵苣，低鉀萵苣的苦澀度較低，鹹度則較高。整體偏好上，低鉀萵苣的得分高於正常葉萵苣。結論：與正常葉萵苣相比，低鉀萵苣的鉀含量較低，但其他營養素含量相似。同時，低鉀萵苣的整體味道偏好比正常葉萵苣較佳。本研究的結果顯示，對於血鉀過高的慢性腎病患者，低鉀萵苣是適合的食物選擇之一。