Can a different pasta making process preserve the starch’s ultrastructure, increasing its digestibility?

BACKGROUND: Pasta plays an important role in human nutrition, nevertheless its organoleptic, structural and bromatologic properties have not been completely studied. OBJECTIVE: The study aims to compare the ultrastructure pasta cross-sections produced with reduced mechanic stress and low heat exposure technique (Pietro Massi Technology ™) to common samples obtained with traditional technology in order to assess if a different process can alter the ultrastructure of starch and then, its digestibility. METHODS: A comparative study was performed on the ultrastructure of pasta using scanning electron microscopy (S.E.M). 55 were pasta cross-sections made with Pietro Massi technology, 33 were samples from different pasta factory produced using traditional process, for a total of 88 samples analysed. RESULTS: According to an Index based on what it was observed at one slide at S.E.M we classified samples and compared the number of grains, caves and canals visible, their dimensions in μm and average size of grains. The number of grains in group 1 (9.06±5.01) in group 2 (5.71±5.77), in group 3 (5.93±7.65) resulted significative more elevated compared to group 4 (0.73±2.58); in group 1 and group 2 the number of caves observed was higher than group 4. The size in μm of canals resulted significantly more elevated in group 1 than group 3 (p = 0.008), group 2(p = 0.013), and group 4 (p = 0.02). CONCLUSION: The analysis of average size of caves and canals in μm, the number of caves and grains demonstrated in samples obtained with Massi technology elevated values compared to samples obtained with traditional technique. The number of caves, grains and canals visible in the starch surface demonstrate the high quality of this pasta because they likely ensure penetration of water during cooking, facilitating at the same time the penetration of pancreatic amylases during digestion, suggesting a better digestibility in pasta produced according to this methodology.