Effects of Cooking Methods on the Retention of Vitamin B₆ in Foods, and the Approximate Cooking Loss in Daily Meals

Abstract

Data were obtained that might be applicable to estimate the cooking loss of vitamin B₆ (B₆) in daily meals against the actual B₆ intake. Based on the result of our dietary survey of 19 healthy women, the amount of B₆ in meals after cooking measured by HPLC was approximately 13% of that before cooking (calculated by the standard food composition table). To further ascertain the actual B₆ loss, the meals from the dietary records were reproduced, and the result obtained from measuring B₆ in these meals before and after cooking also proved to be approximately 13%. Most of the animal foods in the daily meals studied were cooked by dry heating, resulting in a relatively low level of B₆ loss, whereas many plant foods were cooked by wet heating. The cooking loss was greatest when foods were boiled, followed by deep-frying and sauteeing in that order. If the water used for boiling, which can be expected to contain dissolved B₆, was taken with the ingredients, however, boiling was found to result in relatively little B₆ loss.