Synonyms of sugar : glucide, glycide, carbohydrate, carbon hydrate .
Through the cooking of food, various nutritional alterations are created, interesting both from a health and hygiene-food point of view, as well as technical and culinary; of these, some can be considered positive while others, by contrast, are decidedly unfavorable.
Increased solubility of simple sugars - a positive aspect
Dry simple sugars - negative aspects
When dry, cooking sugar (sucrose) during cooking (160 ° C) changes its structure: from crystallized (granulated sugar) to liquid (viscous); further increasing the temperature (170 ° C) the caramelization takes place, or a process of further dehydration which recombines the oxygen atoms of the sugar and favors a molecular re-arrangement producing numerous compounds, simple or complex, volatile and non-volatile. The caramel thus obtained is brown in color, has a dense consistency and a typical smell of "burnt sugar"; represents a set of different components, including: glucosanes, aldehydes, ketones, etc. and it also plays an important role as a "coloring" food additive in the confectionery industry (E150a, E150b, E150c, E150d).
Some will wonder why caramelization is a negative aspect of cooking simple sugars; it is easy to say: at such high temperatures, the production of toxic catabolites such as hydroxymethylfurfural (HMF) and acrylamide inevitably also occurs; this also happens by constantly monitoring the achievement and stabilization of the minimum caramel production temperature. Ultimately, caramelization is a negative aspect for health, as it often causes the release of hydroxymethylfurfural (HMF), a toxic and volatile molecule that is lethal in the rat at about 50-100mg / kg-1 of body weight (100mg / hg ), and acrylamide, or a carcinogenic molecule.
Cook complex sugars (starch) in water - positive aspects
Starch is a complex sugar which swells up to 65-70 ° C in water and swells by absorption (initially only the hydroxyl groups of amylose and amylopectin are involved in the reaction); increasing the temperature up to 90-95 ° C, the reaction accelerates and a gelatinous mass is formed which, by reducing the temperature, acquires a gelling consistency (see "scotta" pasta). A similar reaction is extremely useful in culinary processes that require the thickening of liquid substances, so much so that some food additives are composed of simple cereal flours or legumes, or of the relative starches extracted.
Cook the complex sugars (starch) dry - positive and negative aspects
Unlike cooking in water, which does not have negative effects on health, cooking complex sugars dry at high temperatures results in both positive and negative implications.
A positive result is a partial hydrolysis of the molecules in simpler segments such as: dextrin, maltose and glucose, with a consequent increase in the digestibility of the food. However, by prolonging exposure to dry and high heat, these molecules undergo caramelization in a manner similar to that of simple sugars (with all the negative aspects of the case).
When cooking foods rich in complex sugars but with protein traces it can also trigger the triggering of the Maillard reaction (union of simple sugars with amino groups of proteins); in culinary practice this reaction is quite evident in baking bread which, from 180 ° C onwards, tends to form a brown, crisp and aromatic surface crust (molecules involved by Maillard: gluten and starch hydrolyzed residues).
NB . The Maillard reaction gives food pleasantness but, if excessively activated, it also favors the release of toxic molecules such as hydroxymethylfurfural - HMF and acrylamide.
In conclusion, cooking the sugars causes positive and negative effects depending on the temperature and the cooking mode (dry or in water). Cooking in water never causes damage to health as it is always around 100 ° C; in boiling water, simple cooking sugars (sucrose) dramatically increase their solubility and complex ones (starch) tend to gel, performing a thickening action; on the other hand, strong and dry cooking of sugars is not harmless. To the simple ones it causes liquefaction and then caramelization, preparing the foods cooked to the Maillard reaction; the complex ones (starch) determines an increase in their digestibility (positive) ... BUT also in this case it increases the predisposition to the Maillard reaction, essential in the formation of the organoleptic and gustatory characteristics of cooked food, but also predisposing to the release of toxic and / or carcinogenic molecules.
