Reuse of Dairy Product: Evaluation of the Lipid Profile Evolution During and After Their Shelf-Life

The aim of the present work was the characterization of best-by-date dairy products to evaluate their nutritional value for possible re-introduction in the food or feed chain. The attention was devoted to fatty acids and triacylglycerols characterization and their variation during storage of fresh-cheese products before and after their best-by-date. Three kinds of cheese were selected, namely a classic stracchino, stracchino with the addition of yogurt, and one with the addition of probiotic. The variation of FAMEs and TAGs profiles were studied in order to evaluate the degree of variation occurring in the lipid fraction during storage and after the best-by-date. The extraction method was simply scaled-down by ten-fold, starting from the classical Schmid-Bondzynski-Ratzlaff method. The GC run was sped up after a careful comparison of the result with a conventional analysis. The entire data set of results was evaluated performing both a three-way principal component analysis and a traditional two-way one. The three kinds of samples were well discriminated while a change of the lipid profile over the best-by-date period was particularly significant only for the stracchino added with a probiotic.