Production of high-lysine-content biscuit and examination of the absorption of lysine in humans

Abstract In the Medical and Health Centre of the University of Debrecen, we examined the changes in the free amino acid content of the blood serum of control and experimental individuals after consumption of 2,000 mg of lysine-laden biscuits. We baked the biscuits at 130 °C, during which the greater part (70–75%) of the lysine was not converted into Maillard reaction products. After 30–60 minutes of consumption of the biscuits, the free lysine content of the blood serum increased significantly in the experimental and control group with 41–46%, and even after three hours of consumption the level was 20% higher than in the initial concentration. The free arginine content of the blood serum did not change after the consumption of control and lysine biscuits neither in the control nor in the experimental group. Therefore, the free lysine/free arginine ratio of the individuals consuming lysine increased significantly compared to the initial and the control group’s value. The antioxidant level of the blood serum in the control group remained unchanged after the consumption of the control biscuit, while in the case of the experimental individuals who consumed lysine-fortified biscuits it increased by 40–45% compared to the initial level. Summing up: After consumption of the biscuits with 2,000 mg of free lysine, the concentration of free lysine in the blood serum, its free lysine/free arginine ratio and antioxidant level increased significantly. Our researches have clearly demonstrated that the active substances of the biscuit got into the blood serum, so the investigation of the active substance and the evaluation of the physiological effects are definitely recommended in the long run.