Loss or Gain of Lipophilic Bioactive Compounds in Vegetables after Domestic Cooking? Effect of Steaming and Boiling

Abstract

Lipophilic antioxidants are essential components, which have been pointed as bioactive beneficial for human health. This study aimed at evaluating the effect of domestic cooking (boiling, steaming) on the main carotenoids (lutein and β-carotene) and tocols in four different green leafy vegetables: Sonchus asper L. Hill, Sonchus oleraceus L., Spinacia oleracea L. and Cichorium intybus L. The total content of the analyzed compounds was determined following the method of alkaline hydrolysis of the matrix and solvent extraction. The leaching of soluble solids after domestic cooking was found to determine a gain in the investigated bioactive compounds in the cooked vegetables, so to cause an apparent content increase in all leafy vegetables, when expressed as mg/100 g dry matter. Considering solid losses, all lipophilic compounds were not affected by boiling; on the contrary, steaming slightly significantly decreased the contents of lutein and β-carotene (on average 20 and 15%, respectively).

Influence of Drought Stress on Physiological Responses and Bioactive Compounds in Chicory (Cichorium intybus L.): Opportunity for a Sustainable Agriculture

“…The AOAC methods were used to determine moisture, proteins, ash, and fiber [ 38 ]; fats were analyzed by the method of acid hydrolysis [ 39 ]. Tocols and carotenoids were extracted according to Fratianni et al [ 3 ] and determined according to Panfili, Fratianni, and Irano [ 37 , 40 ].…”

“…Carotenoids were analyzed through a normal (for xanthophylls) and a reverse phase (for carotenes) HPLC method, as in [ 3 , 40 ]. Analysis were performed by using a HPLC Dionex (Sunnyvale, CA, USA) analytical system, comprising a 50 μL injector loop (Rheodyne, Cotati) and a U6000 pump system.…”

“…It is a widely spread crop able to tolerate different climatic and soil conditions, and is commercially cultivated in North America, Europe, and some Asian regions [ 2 ]. Several studies have reported its health benefits [ 3 , 4 , 5 ].…”

Chemical Composition and Nutritional Value of Three Sonchus Species

“…These species are part of the food habits of population groups in several countries, consumed in natural, or submitted to cooking. They are considered sources of dietary fiber and vitamins and strongly contribute to the food security strategies of thousands of people [22][23][24].…”

Advances in Research on Natural Distribution, Biosynthesis, Detection, Bioactivity, and Application of Lutein

“…Lutein contains all its double bonds in the form of the trans isomer, which is partially transformed into the cis form during thermal exposure. The average loss of lutein was 20% during cooking of four different green leafy vegetables: Sonchus asper L. Hill, Sonchus oleraceus L., Spinacia oleracea L., and Cichorium intybus L. . At 160 °C and above temperature, lutein was reduced in all of the treated maize samples.…”