Influence of the Preservation Method on the Nutritional Profile of Elephant Garlic (Allium ampeloprasum L.) Grown in Valdichiana, a Traditional Cultivation Area of Tuscany, Italy

This study investigated the effect of two different methods, i.e. air-drying and freeze-drying, of preservation of elephant garlic (Allium ampeloprasum L.) cultivated in Valdichiana, a traditional cultivation area of Tuscany, Italy, on its nutritional characteristics (i.e. soluble proteins. polyphenols, flavonoids, free radical scavenging activity, starch, soluble sugars, allicin). The results showed that compared to the fresh product, the traditional method of air-drying causes significant reductions only in the total antioxidant power (-46%) and in the content of starch (-22%), while the modern method of freeze-drying negatively affects almost all the parameters investigated, overall by about 40%. The content of allicin is not changed by the preservation method. Although freeze-drying is considered one of the best methods for preserving plant-based food, attention should be paid to the effect of this process on the nutritional characteristics of the product