Today the development of functional foodstuffs is a real challenge for the food industry: these products must meet the expectation of consumers who demand with increased interest food that is healthy and tasty at the same time. The direct consequence is the need for a wide variety of knowledge, especially in technology, to meet the needs and expectations in this area. Pasta, Italian cuisine traditional dish par excellence, is generally produced from durum wheat flour, recognized as the most appropriate ingredient for this process. This food, as well as being economical, represents an important source of complex carbohydrates and can be realized through some basic steps, which can be summarized in the flour mixing phase with water, followed by mixture extrusion and molding, which, ultimately, is subjected to drying treatment. Pasta with ideal physical and sensory properties is characterized by firm and elastic dough, by a high tensile strength in dehydrated form, minimal losses during the cooking phase, and finally, by minimum viscosity and reasonable compactness at the end of the preparation. Anyway, it should be highlighted that the market of pasta could have new input and increase production, and consequently turnover, if alternative or less known ingredients were used, along with cutting-edge technologies. However, the addition of different raw materials, during dough preparation, often involves changes at various levels in the production process. In particular, it is necessary that both dough formulations and technological aspects of the process are properly balanced and adjusted in order to prevent any changes in the rheological and sensory properties of pasta, caused precisely by the addition of these new ingredients.
Why is it important for pasta to be fortified?
Pasta is characterized by the absence of cholesterol, it is low in sodium and fat content and rich in complex carbohydrates; however, it is poor in fibers and deficient in some essential amino acids such as lysine and threonine. To strengthen and improve its nutritional composition, this food may be fortified thanks to non-traditional ingredients. As a matter of fact the success and diffusion of pasta depend on the ability to add supplements such as legumes, cotton seed flour, egg albumin, whey proteins of milk or yeast, rape seeds, fish protein concentrates and dehydrated amaranth leaves flour. These ingredients are interesting both as sources of fibers and proteins, to meet the demand for healthy and balanced food from a nutritional point of view, and for a wide range of opportunities for the food industry, which could improve the quality of pasta during its cooking phase and the structural characteristics of the final product. The qualities and characteristics in pasta cooking phase depend on the properties of dough and, in particular, on protein-starch ratio in the final product: features like texture, cooking losses and pasta viscosity, can be linked to the dough’s protein content, gluten strength, as well as starch composition. The latter, moreover, changes in structure, during gelatinization and retrogradation processes, partly because of technological treatments. As a result, some problems may arise during the preparation of pasta charged with unusual raw materials; therefore a careful selection of ingredients is required: they mustn’t modify the sensory and technological properties of the product, and must be also appropriate and balanced to make them improve. For example, the addition of non-starch polysaccharides (NSP) in the dough mix would have an effect on the bond between proteins and starch, making it stronger, leading it to affect the quality of pasta cooking. In particular, soluble NSP have been used in food industry as thickening agents and stabilizers: many of these, such as guar gum and xanthan gum, are able to create very viscous solutions and a gel thanks to complex bonds with protein components and with starch, thus altering the food structure. Insoluble NSPs tend to be better used as fillers: in fact, generally these additives do not have the ability to form gel-like structures when combined with other components and therefore, they can cause loss of stability in the final product. Among these non-traditional raw materials, legumes represent an interesting source of proteins, fibers, vitamins and minerals; however, a high level of replacement (35% w/w) can decrease the quality of pasta. For example, strengthening it up to 10% with lupine flour or gram flour pasta is generally well accepted but with an increased replacement level, negative variations occur on cooking quality, such as higher losses and stickiness, as well as little acceptability of sensory characteristics. Moreover, it is shown that adding 75% insoluble pea fibers in the pasta increases susceptibility of starch against digestive enzymes, due to the breakage of the protein network that includes the granules.