Morita II and Criolla Stevia rebaudiana varieties, respectively. 

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... is a perennial shrub that extensively grows in places like Brazil, Central America and Israel but is native to Paraguay. The genus Stevia belongs to Asteraceae family, tribe Eupatoriae and comprises of 240 species. This plant grows mostly at the altitude of 500 - 3000 m above sea level in semidry mountainous terrain. Different species of Stevia contain several potential sweetening compounds; Stevia rebaudiana (Bertoni) is the sweetest of all [1]. For centuries this herbal sweetener has been used in native cultures to counteract the bitter taste of various plant based medicines and beverages. Nowadays the extraction of sweeteners from stevia leaves is a grow- ing industrial and commercial worldwide sector; more than 750 tons of stevia leaves per year are used as crude extract for consumption and extraction of glycosides [2]. The sweetening property is associated with their contents of several glycosides, stevioside, steviobioside, rebaudi- osides A to F, dulcoside A and steviol. These glycosides and their derivatives are known to account for 4% - 20% of the dry weight of stevia leaves [3]. Stevia and its extract have been studied widely from the sweetener point of view. However, a search through literature show little information on the no-sweetening components that make up 80% - 90% dry weight of this plant [4] and no information for varieties adapted for cultivation in Mexico. Green vegetables have long been recognized as the cheapest and most abundant potential sources of proteins, starch, dietetic fiber and other micronutrients because of its ability to synthesize these kind of compounds from a wide range of easily available pri- mary materials such as water, carbon dioxide, and at- mospheric nitrogen [5]. According to Aletor and Adebayo [6], leaves and leaf protein concentrates could be used to improve not only the nutritional contribution of food products but also their functional properties. This means that stevia leaf powder or the residue obtained after extraction of sweetening components could be used as additives for the food industry. Therefore the objectives of this study were to charac- terize the proximal content, dietary fiber composition and functional properties of the Stevia rebaudiana (Bertoni) leave powder cultivated in Yucatan, Mexico. Stevia rebaudiana (Bertoni) varieties (Morita II and Criolla) were obtained from plots established in Yucatan, México ( Figure 1 ). The plantation had a crop manage- ment according to the production technology described by Ramirez et al . [7]. Samples were obtained from the first cut of the plot at an age of three months; samples consisted on branches of leaves and stems. All chemicals were reagent grade or better and purchased from Sigma Chemical Co. (St. Louis, MO, USA). The proximate composition of S. rebaudiana leaf powders were determined using AOAC [8] methods: mois- ture content (Method 925.09), ash (Method 923.03), crude fat (Method 920.39), crude protein using a 6.25 nitrogen-protein conversion factor (Method 954.01) and crude fiber (Method 962.09). The carbohydrate content was estimated as the nitrogen-free extract (NFE). This parameter was determined with the gravimetric en- zymatic method proposed by Prosky et al . [9]. Briefly, 1 g of sample was weighed into each of four flasks and 50 mL of phosphate buffer (50.0 mM, pH 6) were added to each. The flasks were then placed in a water bath at 100 ̊C , 0.1 mL of thermostable α -amylase enzyme (Sigma A-3306) was added to each and then they were agitated at 60 rpm for 15 min. After cooling, pH was adjusted to 7.5. The flasks were returned to the bath at 60 ̊C , 0.1 mL protease (Sigma P-3910) added to each and then they were agitated at 60 rpm for 30 min. After cooling, pH was adjusted to 4.0. The flasks were again placed in the bath at 60 ̊C , 0.3 mL amyloglucosidase (Sigma A-9913) added and then they were agitated for 30 min. Finally, ethanol 95% (v/v), preheated to 60 ̊C , was added at a 1:4 (v/v) ratio. In a vacuum, flask content was filtered into crucibles containing celite (Sigma C-8656). The residue remaining in the flask was washed three times with 20 mL of ethanol 78% (v/v), twice with 10 mL of ethanol 95% (v/v) and twice with 10 mL acetone. Crucible content was dried at 105 ̊C . Protein (N × 6.25) was determined for the residue in two crucibles and the residue in the remaining two was burned at 550 ̊C for 4 h. TDF ( % ) =   Residue weight ( g )   − protein ( g ) − ash ( g ) × 1000 Sample weight g This was determined following the method of Prosky et al ., [9], which is similar to that for TDF, except that addition of ethanol 95% (v/v) at 1:4 (v/v) is ...