Antioxidant activity of monoterpenes added to roasted sunflower seeds for the sensory properties preservation

P. R. QUIROGA; ASENSIO C.; LARRAURI, M.; GROSSO, N. R.; NEPOTE V.

Chicago

Congreso; IFT 13 - Annual Meeting and Food Expo; 2013

Institute of Food Technologists - IFT

Oxidation products and rancid flavors decrease the sensory quality of foodproducts making them unacceptable for consumers. Synthetic antioxidants such as BHA and BHT are used in many foods to prevent rancidity. However, their health safety is questioned. Monoterpenes are obtained from essential oils. Many of them have shown antioxidant activity, and could be used as natural antioxidants. The objective of this study was to evaluate the preservation effect on sensory properties of roasted sunflower seeds for the addition of monoterpenes: thymol, carvacrol and sabineno hydrate acting as antioxidant additives. Roasted sunflower (RS), roasted sunflower with addition of BHT (RS-BHT), and thtymol (RS-T), carvacrol (RSCar) and Sabinene hydrate (RS-S) monoterpenes were prepared. Samples were stored during 35 days at room temperature. Intensity ratings of attributes were measured by  escriptive analysis every 7 days. Hexanal content was also measured. Statistical analysis was performed on the data (ANOVA, LSD test and regression analysis). Oxidized and cardboard flavor intensity ratings increased during storage in all treatments being higher in RS. The intensity ratings of roasted flavor decreased much more in RS during storage. At storage day 35, intensity ratings of oxidized flavor in RS-BHT (26.5), RS-T (29.8) and RS-Car (39.5) were lower than the ratings observed in other treatments as RS-S (39.67) and RS (45.92). These results indicate that the addition of monoterpenes showed protection in the product inhibiting the increase of undesirable flavor. Hexanal content increased in all treatments during storage. These indicator was higher in RS and the other treatments. RSBHT was the treatment that showed the lowest hexanal content followed by RS-T and RS-Car. Thymol was the monoterpenes that exhibited the best preservation effect of the sensory properties in roasted sunflower seeds. Monoterpenes as thymol, carvacrol and sabineno hydrate are an alternative as natural antioxidant in high lipid content foods. Industry Relevant Text for use with media (300 word limit): The addition of natural  additives instead of synthetic ones covers the present trend in food technology. The shelf-life of food product could be prolonged by the addition of natural preservatives as monoterpenes. This research showed that the addition of monoterpenes preserved the intensity ratings of positive attributes in roasted sunflower seeds during storage.The addition of monoterpenes should be considered for the food industry as a natural source of antioxidant additives for preserving quality properties in food products with high lipid content