Effect of Hydrothermodynamic (HTD)-Processed Blueberries on Postprandial Blood Glucose Control and Antioxidant Status in Human Adults
Mount Saint Vincent University
The prevalence of diet-related chronic diseases continues to rise in Canada and globally. Healthy lifestyle factors including healthy diets and physical activity are sustainable means of reducing risks of developing chronic diseases. Adequate intake of fruits provides health benefits due to their fiber content and polyphenols. However, conventional processing methods may negatively affect these benefits. Hydrothermodynamic technology (HTD) is a method employing the principle of Venturi cavitation that leads to collision of particles in the turbulent fluid and is used for processing of fruits and berries into puréed products. The aim of this study was to determine the effect of HTD-processed blueberries on postprandial blood glucose control and antioxidant status in human adults. Methods: 25 healthy adults 19-35 years old participated in the study. Using a randomized controlled cross over study design, the participants attended two sessions and consumed one treatment at each session. The following treatments were used: (1) blueberry purée and white bread (196.3kcal, 11.4g sugar, 27.7g starch, 5.3g fiber, 6.8g protein, 0.23g fat), and (2) control: sweetened water and white bread (187.3kcal, 11.4g sugar, 27.7g starch, 1.8g fiber, 6.3g protein, 0.23g fat). After an overnight fast, participants arrived to the laboratory and their fasting blood was collected. The participants then consumed a treatment. Subsequent blood samples were collected at 15, 30, 45, 60, 90, and 120min after the treatment. Results: There was an effect of time (p=0.002) but no effect of treatment (p=0.17) on blood glucose over the 120min. The treatment with blueberries significantly reduced blood glucose by 8.5% at 15 min, and by 6.5% at 30 min compared to the control (P<0.05). There was no effect of treatment or time on postprandial total antioxidant capacity in blood plasma as measured using ferryl myoglobin radical-based assay. Conclusion: In healthy adults 19-35 years, HTD processed blueberry beverage consumed with a high carbohydrate meal reduced blood glucose within 30 min after consumption compared to the control with the same level of glycemic carbohydrate. The HTD-processed blueberry beverage did not affect postprandial antioxidant status as measured by trolox-equivalent antioxidant capacity within two hours.
Hydrothermodynamic technology, blueberries, blood glucose control, antioxidant