The effect of methods and drying temperature on glycoside content (Stevioside and Rebaudioside A) in Stevia (Stevia rebaudiana): A systematic review

The utilization of Stevia rebaudiana as an alternative sweetener in Indonesia is still low, this is caused by a lack of information about its processing from raw material until the extraction process to obtain the glycosides content. Glycosides are the sweetener compound in Stevia rebaudiana with a sweet taste up to 300 times of sucrose, which are stevioside and rebaudioside A. To obtain the glycosides content in stevia, stevia needs to be dried after harvest. Then, dried Stevia will be extracted to obtain the glycosides content. The research method used in this study was a systematic review of selected journals on a specific topic, then were analysed in both the theory and content. The purpose of this research is to analysing the effect of drying temperature on different drying methods on the glycoside compound of Stevia rebaudiana, observing drying temperature that is useful to obtain the optimal glycoside compound in Stevia rebaudiana, and to recommend the utilization of Stevia rebaudiana as an alternative sweetener in Indonesia. The result is the high temperature and low temperature can decrease the glycoside compound in Stevia rebaudiana. The dried temperature that is effective for drying stevia leaves to obtain the maximal glycosides is in the range of 40-60°C. The drying method that is effectively used is by an oven at 60°C as the suggested temperature. Stevia’s sweetener is potentially applied and developed in Indonesia and can be served in powder form because it is more efficient and decrease defect in dried condition and a much longer lifetime.

Optimization on Na and Ca bentonite activation using response surface method for increasing selectivity of stevioside in stevia extract

The demand for stevia extract consumption as an alternative sweetener that contains stevioside with zero-calorie is increasing. However, dark color and high tannin content from stevia leaf extract causes a disturbing aftertaste and reduces interest in consumption. Therefore, the purification process is a mandatory step to be done. Several studies on purification methods show the best approach by adsorption using bentonite. However, natural bentonite has limited adsorption capacity and low selectivity. An activation with acid and high temperature is expected to increase the adsorption capacity of color and its selectivity on maintaining the stevioside at the extract. This study aimed to obtain the optimum acid concentration and temperature for the activation using the Response Surface Method (RSM) experimental design and its application to the purification of stevia leaf extract. Based on the parameter of methylene blue number, the most optimum concentration of H2SO4 used for activation was 0.17 N for both natural bentonite. The heating temperature was 358°C for Na-bentonite and 481°C for Ca bentonite. The maximum adsorption capacities of activated Na and Ca-bentonite were increased from 15.65 and 38.23 mg g-1 to 197.72 and 169.52 mg g-1, respectively. The best adsorbent used for purification is Ca-activated, which increased extract clarification up to 81.37% at 655 nm and 86.64% at 410 nm compared to natural Ca bentonite. It also reduced tannin up to 97.46% and was more selective to recover 50.64% stevia content in the solution, which was higher than other previously reported studies.

Impact of Using Alternative Sweetener as Osmotic Agent on Mass Transfer, Colour and Texture Properties During Dip Dehydration of Apple Slice

Previous study has explored dip dehydration as a novel variant of osmotic dehydration to reduce solid gain, which is the main problem of osmotic dehydration. However, this dehydration process commonly uses sucrose solution as osmotic agent which might contribute to the increase in glycaemic index and can also be linked to different diseases such as diabetes and obesity. Therefore, this study aims to investigate the effect of using alternative sweeteners as an osmotic agent on mass transfer, colour, and texture profiles during dip dehydration of apple slices. Three alternative sweeteners, i.e., erythritol, sorbitol and xylitol with 30% (w/v) concentration were used in this study. Apple slices with 1.5 mm thickness and diameter of 55 mm were dipped multiple time in the same concentrated solution every 40 minutes until 200 minutes before samples were analysed. Findings showed that different type of sweetener affect water loss and solid gain. Xylitol and sorbitol gave highest water loss about 36% and 40%, respectively. Lowest total colour different with fresh apple has been observed in sample treated with xylitol. As for texture, there is no remarkable effect of using alternative sweetener as osmotic agent at all processing times. Overall, the best alternative sweetener for sucrose is xylitol considering the mass transfer and quality of apple slices.

Sweetness profiles of glycosylated rebaudioside A and its binary mixtures with allulose and maltitol

Rebaudioside A is a promising natural alternative sweetener but they produce increased bitterness, astringency, and unpleasant aftertastes. Glycosylation and blending with different sweeteners are known to improve the sensory characteristics of rebaudioside A. The present study was conducted to identify the relative sweetness and sensory profile of glycosyl rebaudioside A (g-reb A). The relative sweetness of g-reb A compared to 5% sucrose was determined using the two-alternative forced choice method. The sensory profiles of g-reb A and its mixtures with allulose and maltitol (1:1 ratio) were compared to those of rebaudioside A, rebaudioside D, rebaudioside M, sucralose, allulose, maltitol, and sucrose using descriptive analysis conducted by eight trained panelists. The relative sweetness of g-reb A was 155, which was lower than that of rebaudioside A. In addition, the bitter taste and aftertaste, astringency, and sweet onset of g-reb A were decreased compared to those of rebaudioside A.

Stevia as a Natural Sweetener: A Review

: Stevia rebaudiana of the Asteraceae family is a perennial shrub. It is a sweetener herb also known as sweet weed, sweet leaf, sweet herbs and honey leaf, native to Argentina, Brazil and Paraguay. The leaves of stevia are sweeter than sucrose with zero calories. Steviol, a diterpenoid glycoside derivative identified from this plant, is sweeter than sucrose and is safe when used as a sweetening agent. Diabetic and obese people with hyperglycemia who are in a condition to follow a strict diet can use stevioside as an alternative sweetener. In addition to its hypoglycemic property, the plant also exhibits antibacterial, anti-inflammatory, hypotensive, antiseptic, diuretic, anti-fertility and cardiotonic properties. It has also been documented to show good effects on treating skin diseases such as dermatitis, acne, eczema etc. The leaves of stevia with enriched phytoconstituents could be an alternative natural sweetener for children, adults and old age persons who have a craze to drink beverages and eat sweetened food products in their habitual life.

Kimpul (Xanthosoma sagitifolium) liquid sugar with low glycemic index

Kimpul (Xanthosoma sagitifolium) is one type of local tuber plant that has high carbohydrate content (34.2g/100g). This plant provides an opportunity to be utilized as an alternative source of sugar. The use of kimpul as liquid sugar becomes an alternative sweetener that needs testing from the perspective of nutrition and health. The Glycemic Index (GI) is a term that is closely related to carbohydrate metabolism, which has the index (level) of food according to its effect on blood glucose levels. The study of the formulating process of kimpul liquid sugar that has a lower GI attempts the use of sugar from kimpul can be more appropriate and well-targeted. This study aimed to determine the engineering process to decrease the GI value of liquid sugar from kimpul through the treatment of tea extract addition and identify the nutritional value, calorific value, GI value, and tannin content in the kimpul liquid sugar as the result of the engineering process. The results showed that the addition of black tea extract with a 2% concentration could reduce the GI value of the kimpul liquid sugar. Thus, kimpul liquid sugar can use as a source of natural sugar with a low GI.

Expression of thaumatin, a new type of alternative sweetener in rice

Sweet proteins are the natural alternative to the artificial sweeteners as well as flavor enhancers. Among other sweet protein, thaumatin protein was isolated from Thaumatococcus daniellii Benth plant fruit. In this study, pinII Ti plasmid vector was constructed with thaumatin gene, where thaumatin was placed under the control of the duel cauliflower mosaic virus 35S promoter into rice (Oryza sativa L. var. japonica cv. ‘Dongjinbyeo’) by Agrobacterium-mediated transformation to generate transgenic plants. Thirteen plant lines were regenerated and the transgenic rice lines were confirmed by different molecular analysis. The genomic PCR result revealed that all of the plant lines were transgenic. The single copy and intergenic plant lines were selected by Taqman PCR analysis and FST analysis, respectively. Expression of thaumatin gene in transgenic rice resulted in the accumulation of thaumatin protein in the leave. Thaumatin protein was also accumulated in leave of T1 generation. Sensory analysis result suggested that the thaumatin protein expressing transgenic lines exerted sweet tasting activity. These results demonstrated that thaumatin was expressed in transgenic rice plants.

Stevia vs. Sucrose: Influence on the Phytochemical Content of a Citrus–Maqui Beverage—A Shelf Life Study

The consumption of sugar-sweetened beverages has been related with the risk of cardiovascular diseases and other pathophysiological situations, such as obesity or diabetes mellitus. Given the increasing awareness on this fact, food industries are developing new products to reduce the amount of added sugar in development of food products development. Accordingly, in the present work, new functional beverages, constituting a dietary source of bioactive phenolics and supplemented with stevia or sucrose, were designed in order to study the influence of the sweetener during processing and shelf-life. This study is of critical for the informed selection of the sweetener based on its effect on the final phytochemical profile of beverages, especially taking into consideration that there are no previous studies on Stevia rebaudiana. Physicochemical features and phytochemical composition, as well as stability of the different beverages concerning these parameters, were evaluated for 90 days during storage under different conditions (refrigeration (4 °C) and room temperature (25 °C) under light or darkness conditions). Physicochemical parameters (pH, titratable acidity, total soluble solids, and color) did not display statistically significant differences between beverages. Storage temperature was the greatest determinant affecting the stability of all the analyzed bioactive compounds (vitamin C, anthocyanins, and flavanones). The main difference between sweeteners was observed in flavanones, which exhibited a higher loss during storage under day light conditions when stevia was added instead of sucrose. In addition, the juices’ colors were rather stable, keeping a reddish coloration and natural appearance throughout the shelf life. Hence, stevia could be considered as an alternative sweetener by the beverage industry.