Patata Rossa di Colfiorito IGP (Solanum tuberosum, L.) and health-promoting potentialities: Do cooking techniques and storage affect chemical profile and antioxidant activity?

Acting as ' antioxidants ', phenolic compounds have been shown to have a potential protective effect against a wide range of noncommunicable diseases. However, their content in plant-based products - and, in turn, their potential benefits - might be affected by the thermal procedures used in food cooking. In light of this, the aim of this work was a characterization of Patata Rossa di Colfiorito (PRC, an Italian PGI red-skinned potato) and an investigation of the impact of cooking and storage on its bioactive compounds, phenolic content, and antioxidant activity. After the harvesting (T-0), samples were analyzed using instrumental analysis (e.g., HPLC-ESI-MS/MS) and a set of chemical assays (total phenolic content, 2,2-Diphenyl-1-picrylhydrazyl - DPPH, 2,2 '-azino-bis(3 '-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid) - ABTS, and oxygen radical absorbance capacity - ORAC assays). Analyses were also performed on boiled, pressure-cooked and one-month-stored (T-1) products. A commercial red-skinned potato (RSP) was also analyzed. Overall, compared with the raw product, both boiling and pressure-cooking led to a significant increase in bioactive compounds (raw: 168.15 mg kg(-1) of fresh matter, FM; boiled: 398.92 mg kg(-1) FM; pressure-cooked: 309.24 mg kg(-1) FM), total phenolic content and antioxidant activity measured by DPPH and ABTS assays. PRC samples showed higher content in bioactive compounds, TPC values and antioxidant activity compared with commercial RSP (with some sporadic exceptions in ORAC values). Interestingly, one month of domestic storage did not affect the freshly harvested product's features. In conclusion, these results highlighted the quality of this local product and its property to withstand thermal processing and storage. We believe that the results we have obtained should be taken into consideration by health professionals, at both local and national levels, and that PRC deserves to be further studied to investigate its potential human health benefits, as well.