A cyclically pressurised soaking process for the hydration and aromatisation of cannellini beans

Abstract

Hydrating beans before cooking reduces cooking time, increases their tenderness and weight and improves their appearance after cooking. In this paper, we describe a process of cyclically pressurised soaking for the rapid hydration of cannellini beans at room temperature. This hydration process is approximately ten-fold faster than the traditional soaking procedure, and the microbial load developed by the end of this process is much lower compared to that obtained using the traditional process. This bean hydration process was achieved with a new extraction technique using the Naviglio extractor, which subjected the water containing the beans to cycles of pressurisation in which the pressure values ranged between 0 (atmospheric pressure) and 10bar. This innovative hydration process (I) reduced the time required for the complete hydration of the beans to approximately 60min and produced a product saturated with the same final amount of moisture as the product obtained from the conventional soaking process (T) that lasts 12–20h. The numerical simulation of the hydration process (I) has provided useful indications on how the diffusion of humidity inside the beans occurred during the pressurised soaking process. The treated beans were packaged, and organoleptic tests, including taster panel tests, were conducted. Finally, the aromatisation of the legumes was conducted in conjunction with the hydration process to introduce flavouring elements used in some famous traditional recipes for Italian cuisine.