Glycemic Index of Traditional Egg Pasta

Overview

The glycemic index (GI) compares the plasma glucose response to a specific amount of carbohydrates with the response induced by the same amount of carbohydrates from a standard carbohydrate source, pure glucose in our case. The GI is defined as the incremental area under the curve (iAUC) for blood glucose after consumption of a test food divided by the iAUC of a reference food containing the same amount of carbohydrates. GI is based on the physiologic functions of food carbohydrates rather than on their chemical structure, allowing to a more accurate classification. Several studies found that the regular consumption of low glycemic meals reduces the risk of developing diabetes, insulin-resistance, cardiovascular and neoplastic diseases. GI was originally developed for insulin-resistant subjects. The maintenance of stable blood glucose levels is a challenge for people with diabetes and pre-diabetes and is also beneficial for the general population, as reported by several studies. Low-GI diets have been shown to: * stabilize blood sugar levels * improve body weight * better control appetite * improve memory * reduce the risk of cardiovascular diseases * reduce the risk of some forms of cancer According to Walter Willet, nutrition researcher at the Harvard School of Public Health, an excess of sugars and refined starches stimulates insulin hypersecretion, hunger pangs and frequent snacking, slowing down lipid metabolism and making people physically less active. This project aims to evaluate the glycemic index of five different types of pasta with the same format, named "Fettuccine", but with different composition (the pasta format is related to GI variations). The different types of pasta vary for flour and egg composition. However, having the same format, the GI will change only in response to the percentage content of the ingredients used to produce pasta. In particular, the aim is to measure egg's effect, distinct in yolk and white, on the glycemic and insulin response of healthy subjects.

The five types of pasta to be tested are produced by the so called "La Campofilone" Company (Ficiarà, Campofilone, Marche), a national excellence in the production of traditional egg. Every pasta is designed and realized with the scientific support of two consultants: Prof. Paolo De Cristofaro, endocrinologist, diabetologist and professor at the School of Specialization in Food Science and Nutrition at the University of Chieti, and Prof. Giampiero Sacchetti, biotechnologist at the Marche Polytechnic University. Specifically, the products to be tested are: 1. Traditional Fettuccine, original recipe (8 eggs/kg flour) currently available on the market; 2. Pasta with only 8 egg whites/kg flour; 3. Pasta with 4 eggs/kg flour; 4. Hyperproteic pasta (with added gluten and albumin); 5. Pasta with only 4 egg whites/kg flour. Each phase of the project will be implemented in accordance with the Jenkins and Wolever protocol (World Health Organization-Food and Agriculture Organization of the United Nations,1998). 12 healthy subjects, aged 18-65 years, will be recruited. After a 10 to 12-hour overnight fasting period, standard food (a glucose solution) and food test (the different types of fettuccine La Campofilone) will be administered to volunteers, organized into groups of two or three people. Both test food administrations and standard food administrations will take place on a different day. The standard food consists of 50 g of glucose dissolved in oligomineral water, the test food consists of a portion of pasta containing 50 g of available carbohydrates. Blood samples for determination of glycemia and insulinemia will be taken at time 0 and then at 15, 30, 45, 60, 90 and 120 minutes from the beginning of the test or standard food intake. Three glucose response curves will be performed on each subject (this allows to obtain an average value of the subject's response to glucose over time) while a single test with the food to be tested will be done. Blood samples will be analyzed at the Service of Medical Laboratory Analysis of the Hospital "S. De Bellis". Glucose and insulin values will be used to calculate the glycemic and insulin index of each product. For each type of tested pasta, a detailed report will be drawn up, complete with graphs of glycemic response for each subject. Each report will include the glycemic and insulin index of the product under review.