NUTRACORE, Glycaemic Index and Appetite

For these reasons, in recent years the food industry has tried, not always successfully, to experiment with alternative formulations for its products, implementing a series of techniques to reduce the GI of foods, in particular those based on cereal flour. There are different methods useful to reduce the GI; in particular, the most impacting aspects of the GI of food containing carbohydrates are the sugar content, the starch content, the type of starch, the cooking method, previous processing, pre-cooking, post-cooking cooling, soaking, particle size and fiber quantity.

Increased consumption of soluble fiber is associated with reduced absorption of sugars in the intestine and therefore a reduced GI. On the contrary, most of the fibers contained in cereals and tubers are not soluble. For this reason, the direct effect of fibers on glycemic absorption is not significant. On the other hand, whole grains generally have a lower glycemic index than refined grains and this may be due to a combination of factors such as reduced digestibility, higher starch-content resistance, and the effects of other constituents of bran (such as lipids). Insoluble fibers are also attributed to a greater satiating effect.

The determination of the glycemic index can be estimated in vitro with good accuracy through an artificial digestive apparatus, or dynamic gastric model (DGM) but the gold standard remains the analysis of the glycemic response on subjects in vivo, typically volunteers. The ISO standard 26642 guidelines of 2010 represent the gold standard for the analysis of GI in humans and consists of a few simple steps that require blood sampling to determine blood sugar at the time 0, 15, 30, 45, 60, 90, and 120 min. The GI is but the average of the proportions between the sum of the 7 areas created by placing time on the abscissa (in minutes) and the ordinate blood sugar levels at each T (expressed in mmol/L or mg/dl) after consuming the test food compared to the sum of the areas created after consuming the reference food, usually glucose.

Secondly, the modulation of the intake of sugars and calories can also be managed through alternative methods. It has been seen that, for example, different stimuli related to the sense of taste can modulate the sense of hunger and consequently the calorie intake in the following hours. This is especially true with the bitter taste. Appetite modulation due to the administration of particular foods was primarily associated with particular polymorphisms of receptor genes associated particularly with a bitter taste (TAS2R) and sweet (T1R2-T1R3). At the same time, the discovery of extra-oral receptors to recognize bitterness (extra-oral TAS2R) led the researchers to test the effects of administering particular bitter foods without the potential confounding effect of oral ingestion.

Among recent studies, some researchers have shown that the effect of reducing energy intake has not been statistically significant in a group of overweight women, at least for some types of encapsulated bitterness while others have proven that an intragastric infusion of bitters significantly reduced hunger in a group of normal-weight women. Another study, in the short term, showed instead that an administration of bitters encapsulated with the base of 'Gentiana Lutea' during the morning meal can significantly reduce the energy intake of the day.

Different types of bitters can stimulate different receptors of the TAS2R family. A recent review showed that the bitters most tested and used to determine changes in hunger and energy intake were Quinine, Denatonium Benzoate, Naringin, Secoiridoid, Hops, and Gentian. Bitter compounds, in comparison to other flavors, have proved to be the most effective in influencing eating behavior. This highlights the potential preventive role of bitter flavors in the fight against epidemic obesity. However, further studies are needed to understand which bitters are most useful for this purpose, and which subcategories of the population are most effective. Artemisia Absinthium is an edible and non-toxic plant, commonly called wormwood, for which analgesic, anti-inflammatory, and antidiabetic effects are documented. The bitter extract of this plant, if properly encapsulated, could also affect appetite regulation.The purpose of the first phase of this study is to test the GI of 3 different formulations, in the form of dietary biscuits, on 12 healthy volunteer subjects in order to calculate an average GI necessary for the company that provides the product to enrich the label with a final IG and start marketing. In the second phase, the same subjects will participate in a crossover study to test the same parameters of the first phase, with the addition of an investigation on the effects on hunger with 2 formulations of biscuits different from the first 3, one containing bitter encapsulated Artemisia Absinthium base. The chemotype of Artemisia absinthium used for the extract used is thujoni-free and therefore has no documented contraindication.

Inclusion criteria

• Absence of allergies or intolerances to tested foods
• Absence of drugs that affect glucose metabolism. Stable doses of oral contraceptives, acetylsalicylic acid, thyroxine, mineral supplements, medications for hypertension or osteoporosis are accepted.

Criteria for exclusion:

• diagnosis or history of diabetes or reduced glucose tolerance.
• surgery or severe and acute illness in the last 3 months
• use of steroids, protease inhibitors or antipsychotics