What effect does the addition of SmartSalt® have upon the important bioactive compounds found in peas when added during cooking?

Abstract

Background: Evidence indicates that excessive dietary sodium intake is the leading cause of hypertension. 1 in 4 UK individuals now suffer from hypertension, costing the NHS over £2 billion annually. Though it is recommended that adults consume no more than 6g of salt per day, the UK population continue to exceed this recommendation. 15% of the salt consumed by UK individuals is added either during cooking or at the table. Several low-sodium salt alternatives have been developed to help tackle this issue. One such alternative, known as SmartSalt®, contains 40% less sodium than regular table salt; however, no evidence regarding the effect of the addition of SmartSalt® during home cooking currently exists. The aim of this study was, therefore, to investigate the effect of the addition of SmartSalt® (SMS40) during cooking upon the levels of bioactive compounds found in peas. Methods: Frozen peas were prepared by microwaving, boiling, or steaming. Each cooking method was undertaken for each salt variable; these were no salt, 1g table salt, 1g LoSalt, and 1g SmartSalt®. This was conducted on three separate occasions. The resulting cooked peas and cooking water samples were subjected to laboratory analysis in order to determine their levels of antioxidant activity, total phenolics, chlorophyll A and B, and total carotenoids. These results then underwent analysis by one-way ANOVA to determine whether SmartSalt® had had a significant effect on the retention of these bioactive compounds during cooking in comparison to the other salt variables. Results: Following cooking, variations in the peas' bioactive compound concentrations became apparent. The total phenolic concentrations of the cooked peas showed the least variation and were almost identical to that of the untreated peas, indicating that this bioactive compound was better retained than any of the other compounds following cooking. Only one significant difference was found between cooking with SmartSalt® and cooking with any other salt variable; microwaving with SmartSalt® retained a significantly greater level of antioxidant activity than microwaving with no salt (p=0.015). All other significant differences were found within the salt variables, making it difficult to demonstrate the effect of SmartSalt® upon the retention of the peas' bioactive compounds in comparison to that of the differing salts. Conclusions: SmartSalt® only significantly increased the retention of the peas' bioactive compounds in one instance; however, its addition also did not significantly reduce the retention of these compounds. Therefore, it was concluded that SmartSalt® fared no better, nor worse, than any other salt used in the current study in regards to the retention of the bioactive compounds found in peas during cooking. SmartSalt® remains an excellent alternative to regular table salt, which is essential in the effort to combat the UK population's excessive sodium intakes. With further research, and modification of this study's design based on its limitations, the full extent of SmartSalt's® effect upon the retention of the important bioactive compounds present in a number of foods during the cooking process may eventually be demonstrated. Key Words: SmartSalt®, Sodium, Blood Pressure, Cardiovascular Disease,Hypertension, Phytonutrients.