Since the 50s of last century, the production of oil extracted from seeds and oleaginous fruits has increased significantly becoming of great importance in the agricultural worldwide economy. The increased demand has resulted in a significant expansion of the area under oilseed crops. The edible oils are commonly classified into oils extracted from fruit and from oilseeds. This latter group include byproducts of industrial processes as the grape seed from wine industry. In Italy almost all the oilseeds are usually extracted with hexane and commercialized only as refined oils. The refining processes that apply high temperatures induce almost a total disappearance of the phenolic compounds from the oil as also confirmed by a screening on different samples before and after these treatments1. Nevertheless, in several countries of South America, mainly Argentina and Chile the cold-pressed grape seed oil is widely used for human consumption; its pleasant and characteristic taste make it suitable, as for olive oils, to be consumed as crude condiment to flavor dishes. To date, scant data are available on the content of minor polar compounds in these unrefined oils2. Aim of this work was to investigate on the phenolic fraction of two cold pressed grape seed oils from different provenience. The oils were extracted with ethanol/acidic water 7/3 to recover lignans and other more simple phenols. The alcoholic extracts were then analysed on reverse phase by HPLC/DAD/MS on reverse phase and by targeted MS/MS experiments operating in negative ionization mode. The presence of lignans, in particular pinoresinol and one isobar was confirmed in both these oil in comparable amounts to those found in a commercial olive oil (close to 5 mg/L). Some hydroxycinnamic acids and flavonols such as kaempferol and its derivatives were identified by the help of their spectra. Moreover, the MS/MS experiments allowed to identify two ethyl esters of p-coumaric acid and p-methoxy cinnamic acid not identified to date in grape seed oil. These preliminary data suggest future investigations on a wide number of samples to define the phenolic profiles, to evaluate the antioxidant capacity and the health benefits of the cold pressed grape seed oil.
Cold pressed grape seed oils: a study on their phenolic content by HPLC/DAD/MS and HPLC/MS/MS
ARLORIO, Marco;COISSON, Jean Daniel;
2014-01-01
Abstract
Since the 50s of last century, the production of oil extracted from seeds and oleaginous fruits has increased significantly becoming of great importance in the agricultural worldwide economy. The increased demand has resulted in a significant expansion of the area under oilseed crops. The edible oils are commonly classified into oils extracted from fruit and from oilseeds. This latter group include byproducts of industrial processes as the grape seed from wine industry. In Italy almost all the oilseeds are usually extracted with hexane and commercialized only as refined oils. The refining processes that apply high temperatures induce almost a total disappearance of the phenolic compounds from the oil as also confirmed by a screening on different samples before and after these treatments1. Nevertheless, in several countries of South America, mainly Argentina and Chile the cold-pressed grape seed oil is widely used for human consumption; its pleasant and characteristic taste make it suitable, as for olive oils, to be consumed as crude condiment to flavor dishes. To date, scant data are available on the content of minor polar compounds in these unrefined oils2. Aim of this work was to investigate on the phenolic fraction of two cold pressed grape seed oils from different provenience. The oils were extracted with ethanol/acidic water 7/3 to recover lignans and other more simple phenols. The alcoholic extracts were then analysed on reverse phase by HPLC/DAD/MS on reverse phase and by targeted MS/MS experiments operating in negative ionization mode. The presence of lignans, in particular pinoresinol and one isobar was confirmed in both these oil in comparable amounts to those found in a commercial olive oil (close to 5 mg/L). Some hydroxycinnamic acids and flavonols such as kaempferol and its derivatives were identified by the help of their spectra. Moreover, the MS/MS experiments allowed to identify two ethyl esters of p-coumaric acid and p-methoxy cinnamic acid not identified to date in grape seed oil. These preliminary data suggest future investigations on a wide number of samples to define the phenolic profiles, to evaluate the antioxidant capacity and the health benefits of the cold pressed grape seed oil.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
