152 Novel food packaging techniques influence of both viscosity and binding interactions with the thickener on the elease of flavour. Binding interactions with carbohydrate-based thickeners are often due to adsorption, entrapment in microregions, complexation, encapsulation and hydrogen bonding between appropriate functional groups Kinsella, 1989, Damodaran, 1996). The presence of disaccharides, lactose and saccharose was able to bind water and cause a salting out effect of the lesser polar flavour compounds, linalol and ethyl 2-methylbutyrate, resulting in an increased absorption in the polymer. Also Godshall (1997)reported that disaccharides can lower the amount of bulk water due to hydration, which increases the effective concentration of flavour compounds and therefore can enhance their absorption into polymers The main effect of the influence of the food matrix on flavour scalping, owever, is the presence of oil or fat. Even a small amount of oil (50g/f)had a major effect on the amount of flavour absorption. Absorption of limonene and decanal is reduced to approximately 5%. A quantity of oil as low as 2 g/l results in a decrease of about 50% of absorption, meaning that the presence of oil very strongly influences the level of absorption of flavour compounds in polymeric packaging material(Fig. 8.4) The composition of the food matrix plays a major role in the absorption of flavour compounds by LLDPE. Several studies have already revealed that flavour compounds interact with oil, carbohydrates and proteins, but the Limonene Linalool 2MB E08 Concentration oil (g/l) Fig. 8.4 Influence of oil on the relative absorption of limonene, decanal, linalool and ethyl-2-methylbutyrate(E2MB) by LLDPE after one day of exposure at 4(Van Willige et al., 2000a)influence of both viscosity and binding interactions with the thickener on the release of flavour. Binding interactions with carbohydrate-based thickeners are often due to adsorption, entrapment in microregions, complexation, encapsulation and hydrogen bonding between appropriate functional groups (Kinsella, 1989; Damodaran, 1996). The presence of disaccharides, lactose and saccharose was able to bind water and cause a salting out effect of the lesser polar flavour compounds, linalol and ethyl 2-methylbutyrate, resulting in an increased absorption in the polymer. Also Godshall (1997) reported that disaccharides can lower the amount of bulk water due to hydration, which increases the effective concentration of flavour compounds and therefore can enhance their absorption into polymers. The main effect of the influence of the food matrix on flavour scalping, however, is the presence of oil or fat. Even a small amount of oil (50g/l) had a major effect on the amount of flavour absorption. Absorption of limonene and decanal is reduced to approximately 5%. A quantity of oil as low as 2 g/l results in a decrease of about 50% of absorption, meaning that the presence of oil very strongly influences the level of absorption of flavour compounds in polymeric packaging material (Fig. 8.4). The composition of the food matrix plays a major role in the absorption of flavour compounds by LLDPE. Several studies have already revealed that flavour compounds interact with oil, carbohydrates and proteins, but the Fig. 8.4 Influence of oil on the relative absorption of limonene, decanal, linalool and ethyl-2-methylbutyrate (E2MB) by LLDPE after one day of exposure at 4º (Van Willige et al., 2000a) 152 Novel food packaging techniques