This study aims to investigate whether the heat treatment applied during the production of black onion, a novel derived product made from fresh onion, produces changes in the content of flavonoids, organosulfur compounds, organic acids, water soluble sugars and amino acids in three onion varieties ('Shallot', 'Chata' and 'Echalion'). The total flavonoid content decreased up to 12-fold in black onions compared with fresh onions while the quantities of isoalliin, the main organosulfur compound in black onions, drastically increased during the process. Moreover, the levels of fructose and glucose significantly increased during the elaboration process, contributing to the sweetness of black onions.
View Article and Find Full Text PDFBlack garlic is made from the fresh kind, submitting it to a controlled temperature (~65 °C) and humidity (>85 °C) for a prolonged period of time. The aim of this study was to assess the differences in the process and in the final product as a result of employing three garlic varieties ( and ), and to check the influence of the storage time on fresh garlic in the quality of the final product by using garlic obtained in two different agricultural seasons, that of the current year (2014) and of the previous one (2013). The results revealed some differences in the parameters analysed during the manufacturing of the black garlic from the three varieties used, and even according to the harvest in question.
View Article and Find Full Text PDFWhite and three types of black garlic (13, 32, and 45 days of aging, named 0C1, 1C2, and 2C1, respectively) were selected to study possible differences in their nutraceutic potential. For this purpose, garlic were physicochemically characterized (Brix, pH, aW, L, polyphenol, and antioxidant capacity), and both in vivo and in vitro assays were carried out. Black garlic samples showed higher polyphenol content and antioxidant capacity than the white ones.
View Article and Find Full Text PDFBlack garlic was processed at three different temperatures of heat treatment (72°, 75° and 78°C) and close to 90% of relative humidity. Two types of material source were used: whole bulbs and peeled cloves. Total soluble solids content (°Brix), pH, water activity (aw), browning intensive (L value), total polyphenol content, antioxidant capacity and total polyphenol index of the raw and heated garlic were determined.
View Article and Find Full Text PDFFree-choice profile (FCP), developed in the 1980s, is a sensory analysis method that can be carried out by untrained panels. The participants need only to be able to use a scale and be consumers of the product under evaluation. The data are analysed by sophisticated statistical methodologies like Generalized Procrustean Analysis (GPA) or STATIS.
View Article and Find Full Text PDF