Pasta highly enriched with vegetables: from microstructure to sensory and nutritional aspects

A lifestyle that combines poor food choices with very low or no physical activity can result in the development of diseases such as obesity, and this is affecting a growing number of children. One of the most effective strategies to fight obesity combines physical activity and the consumption of low energy-dense foods, such as vegetables. Vegetables are known to have health benefits but are often non-appealing to children/adolescents due to their bitterness, undesired texture, and their low satiating capacity. One of the possible solutions to increase vegetable intake by children is to incorporate vegetables in a food matrix they like. Several studies have shown that pasta is very much appreciated by children, making it an ideal candidate for the development of vegetable-enriched foods. In this work, dried broccoli powder (BP) was used to enrich pasta-like products. We have investigated aspects that are important to sensorial properties and aspects related to possible health benefits. One aspect relevant to sensorial properties is rheology. The rheology of sweet potato starch (SPS) dough was drastically affected by high volume fractions of BP. This was caused by the swelling of the broccoli powder, up to a maximum of 7.6 times their original volume. In order to control this high swelling capacity of the particles two approaches were followed and both resulted in the prevention of particle swelling. The first was the use of hydrocolloids with high water binding capacity (e.g. xanthan gum) and the second was the use of a different matrix (durum wheat semolina (DWS)). DWS pasta did not show to be greatly affected by the incorporation of high amounts of broccoli powder. The acceptability of pasta products was assessed using a test panel. The results showed that all samples tested (0 – 30%BP) were acceptable, where 30% BP turned out to be on the limit of acceptability. Glucosinolates (GLs) are phytochemicals that are associated with the health benefits of broccoli. An increasing volume fraction of broccoli powder resulted in an increasing content of glucosinolates in dried cooked pasta. At volume fractions higher than 20% BP this effect levels off. From this work, we can conclude that as much as 20% BP can be added to DWS pasta to improve nutritional properties (in terms of GLs) while maintaining acceptable sensorial properties.