CARBOHYDRATES AND TOTAL PHENOLIC CONTENTS OF DOMESTIC COOKED ARTICHOKE

Artichokes have a health-promoting potential attributed to their high antioxidant activity due to their high phenolic content, and to the presence of inulin that has prebiotic properties. Through fermentation, inulin affects bowel functions and microbial enzymes activities. The products of the fermentation process are short chain fatty acids and gases such as carbon dioxide and hydrogen. The gas production can also induce discomfort for some people and lead them to reduce artichoke consumption. The present work focused on the changes occurring in artichoke after some of the common household cooking treatments (pressure-cooking, steaming, microwaving, conventional boiling and the adding of ingredients to the boiling water) on the content of carbohydrates and total phenolic (TPC). Carbohydrates content was determined by anion exchange HPLC with pulsed amperometric detection, and TPC according to the Folin-Ciocalteu procedure. Cooking water was also analysed. TPC was the highest in steamed and boiled artichokes. All cooking methods induced inulin concentration and DP changes. A decrease in the higher polymerized fractions (degree of polymerization, DP>40) with an increase in the less polymerized fractions (DP<10) was observed in cooked artichokes. When pressure cooked, artichoke lost about 13% of inulin, while the boiling cooking resulted in losses of 26%. The leaching of soluble sugars and inulin mainly occurred in boiling cooking. The pressure cooking exhibited the less deleterious effects in inulin when compared to other treatments. Addition of citric acid using the boiling method caused greater inulin loss (reducing the inulin content by half) than conventional boiling. This could be an appropriate cooking option to reduce negative side-effects for some people suffering from intestinal discomfort.