JustSweet in food: Application, Stability, and Interaction with food Ingredients
The solid sweetener stevioside, which is used in JustSweet demonstrated high stability throughout a one-hour incubation time at high temperatures up to 120°C, although forced degradation was detected at temperatures over 140°C, culminating in total decomposition by heating up to 200°C (Fig. 1).
Consequently, stevioside as a sweetening ingredient may not be suitable for all baking methods or procedures requiring high temperatures, but in most cases, the time and temperature will be lower and shorter than that used in such an experiment.
Remarkable Stable over a wide range of pH and Temperature
Stevioside is extremely stable in an aqueous solution over a wide pH and temperature range. At 60°C, practically no degradation of stevioside was observed after 2 hours of thermal treatment in a pH range of 2 to 10. Heating at 80°C resulted in only minor losses of up to 5% (pH 2 and 10). Forced decomposition of stevioside was observed under strongly acidic conditions (pH 1), resulting in total decomposition after 2 hours of incubation at 80°C (Fig. 2).
Only traces of steviol biocide and glucose were detected as stevioside degradation products, which could be attributed to the rapture of the C19 ester bond in stevioside.
Organic acid Stability Research
Stability studies of stevioside in diluted organic acid solutions (1 and 10 g/L) at room temperature.
Fig. 2 pH stability and rate of degradation of stevioside under thermal treatment in a pH range of 1-10. (By Gerhard Kroyer, Stevioside and Stevia – Sweetener in food: application, stability, and interaction with food ingredients).
Acetic acid, citric acid, tartaric acid, and phosphoric acid for up to 4 months proved a preference for enhanced decomposition of the sweetener at lower pH levels depending on the acid media.
Although no evidence of degradation was found after 4 months of storage at room temperature in a 1 g/L solution of acetic acid (pH 3.1), citric acid (pH 2.6), and tartaric acid (pH 2.6), 30% losses occurred in equivalent solutions of phosphoric acid (pH 2.2). After 4 months of storage in 10 g/L solutions of acetic acid (pH 2.6), citric acid (pH 2.1), tartaric acid (pH 2.1), and phosphoric acid (pH 1.6), losses in the stevioside concentration of 2, 22, 33, and 75% were observed. Figure 1 shows the time-dependent degradation rates.
Fig. 3 Degradation rate of stevioside in 1% organic acids at room temperature
Fig. 4 Degradation rate of ascorbic acid as standard substance and in presence of stevioside, filled square on solid line ascorbic acid + stevioside, filled diamond on broken line ascorbic acid – standard
Vitamin interaction
Up to 4 hours of incubation of stevioside in an aqueous solution with individual water-soluble vitamins of the B-group and vitamin C at 80°C revealed no significant changes in sweetener concentration or vitamin concentration regarding the B-vitamins under heat processing as well as in untreated samples. In the case of vitamin C, however, incubation at 80°C resulted in a time-dependent degradation of ascorbic acid. In contrast, stevioside had a protective effect on the degradation of ascorbic acid, resulting in a delayed degradation rate of vitamin C in the presence of stevioside (27% after 4 h incubation) compared to the comparable treated standard substance (13% after 4 hours incubation). Figure 4 depicts the time-dependent degradation rates of ascorbic acid during storage experiments.
Studies on Interactions with Other Low-Calorie Sweeteners
Binary aqueous solutions of stevioside with the other individual low-calorie sweeteners saccharin, cyclamate, aspartame, acesulfame, and neohesperidin dihydrochalcone were investigated in terms of the practical application of low-calorie sweeteners in synergistic mixtures thereof. Thus, excellent stability and no interaction between the individual sweeteners were discovered during thermal treatment at 80°C for up to 4 h as well as 4 months incubation at room temperature, indicating that there are no chemical objections to using stevioside alongside other low-calorie sweeteners.
Hot beverage stability and interaction studies
An intriguing topic about JustSweet because many consumers use JustSweet to sweeten coffee, tea, and other beverages.
Thermal treatment at 80°C of JustSweet or stevioside-sweetened coffee and tea beverages for 4 hours had no discernible effect on either the caffeine or stevioside content. Only minor stevioside losses of up to 5% were observed after 4 hours of warm-keeping of tea or coffee, indicating that no interaction effects should be expected under practical conditions of preparing and consuming hot beverages.
Conclusion
According to the results of the stability and interaction studies, the low-calorie sweetener JustSweet has good stability under normal application conditions. However, chemical degradation of the sweetener occurs under extreme temperature and pH value conditions. Furthermore, specific aspects of potential interaction with other food ingredients should be considered, particularly for its application in various food categories.
More information about JustSweet and its ingredients is available from this site.
References/Sources:
Kroyer, Gerhard. “(PDF) Stevioside and Stevia-sweetener in Food: Application, Stability, and Interaction With Food Ingredients | ANAMARIA POP – Academia.edu.” (PDF) Stevioside and Stevia-sweetener in Food: Application, Stability, and Interaction With Food Ingredients | ANAMARIA POP – Academia.edu, 11 Feb. 2010, www.academia.edu/23275231/Stevioside_and_Stevia_sweetener_in_food_application_stability_and_interaction_with_food_ingredients.
