Water dynamics of ready to eat shelf stable pasta meals during storage

This work reports for the first time a study of physico-chemical changes in cooked and sterilized pasta meals (pasta 25% and sauce 75%) during 34 days of storage. Water dynamics were studied with a multi-analytical and multidimensional approach: moisture content, water activity and 1H mobility (1H T2 and T1 relaxation times and 1H self diffusion coefficient [D]) have been considered. Macroscopic structure (hardness) of pasta meals became softer during storage. Moisture content and water activity changes did not highlight a macroscopic water migration between the pasta and sauce phases.1H T2 was found to decrease in pasta and more markedly in sauce during storage while 1H T1 increased the mobility in pasta and decreased in sauce. 1H translational mobility (D) was found to decrease more significantly in sauce than in pasta during storage. A water migration between the pasta and sauce phases observable at molecular level was therefore hypothesized.