Effect of various thermal processing methods and pretreatment methods to reduce phosphorus content of chicken meat for CKD patients

Purpose The management of dietary phosphorus in chronic kidney disease patients is an important issue. Phosphorus is often found with protein in foods. However, excessive protein restriction worsens the nutritional status of the patient; thus, phosphorus must be selectively restricted. This study aims to assess the effects of various pretreatments readily available in ordinary households on phosphorus loss in foodstuffs. Design/methodology/approach This study evaluated the retention of phosphorus in cooked chicken meat (boiled, baked, steamed and microwaved). In addition, this study incorporated various pretreatments (pounding, stabbing, cutting and enzymatic treatment) to the method exhibiting the lowest phosphorus retention (boiling) and assessed the effects on phosphorus retention. Findings Boiling (65%, vs baking, p < 0.001; vs steaming, p = 0.013; vs microwaving, p = 0.002) of the chicken meat resulted in the lowest phosphorus retention compared to the other cooking methods (baking [89%], steaming [73%] and microwaving [75%]). In addition, stabbing (58%, p = 0.009) or cutting (46%, p < 0.001) further reduced the retention of phosphorus in boiled chicken meat. The retention of phosphorus in enzyme-pretreated boiled chicken was reduced by approximately 10% compared to untreated chicken (p = 0.01). The cooking method that reduced phosphorus retention to the greatest extent was enzyme treatment prior to cutting and boiling. Originality/value This paper investigates the effects of common household cooking methods and combinations of methods on the phosphorus content of meat.