Stevia extract

Stevia extract or an artificial sweetener like Equal . This will make it less bitter and more pleasant to chew. 

Pure stevioside is a white hygroscopic powder (The Merck Index, 1976) and commercial extracts vary from cream to tan powders. The solubility of pure stevioside in water is 1.2 g/1 (The Merck Index, 1976). Commercial extracts have solubilities that range from 300 to 800 g/1 (Stevia Corporation, 1986). The relative sweetness of stevia extracts varies from 15 to 300 (O Donnell, 1983 Richard, 2002 Tunaley et al., 1987 ) The taste of stevioside is characterised by a lingering sweetness and liquorice, bitter off-taste (O Donnell, 1983). This limits its commercial application and it is generally not used as a sole sweetener in most applications. 

The metabolism of stevia and stevia extracts has been the subject of much discussion. The available data are inconsistent and it is unclear whether steviol, the aglycone portion of stevioside, is generated in the gut. Steviol produces a mutagen (Phillips, 1987). The generation of steviol has been demonstrated in vitro and in vivo in rats (Phillips, 1987). 

Remarks to toxicological studies Neither those scientific studies where Stevia extract or solution of pure stevioside were injected in animals, nor those studies employing perfiision experiments of organs, are considered relevant for the use of Stevia or stevioside as food and are not discussed in this review. 

An oral LD50 of 17 g/kg body weight was shown for the Stevia extract (20 % of stevioside) and 15 g/kg for purified stevioside (purity of 93.5%). With rats and mice a LD50 of 8.2 g/kg was found for stevioside by oral intake, and given intraperitoneally, a LD50 of 2.99 g/kg of body weight [18]. 

High doses of 525 mg/kg/day of stevioside equivalent aqueous Stevia extract were administered to male and female mice during copulation and pregnancy periods [19]. The authors could not observe any difference in the copulation and conception averages and any change in the fetus and broods when compared with control groups. 

Besides the lack of effects of Stevia extracts or stevioside in experiments on fertility, no negative reports on human fertility have appeared since the use of Stevia and stevioside in Japan (since more than 25 years), the USA (since 1995) or in other countries. 

In experiments 60 human volunteers received 27.7 mg or 110.8 mg of pure stevioside per day [33]. The author concluded that concentrated Stevia extracts in normal doses to sweeten could be used without restriction by normal persons as well as by diabetics. 

Although rather high concentrations of stevioside and Stevia extracts were shown to reduce the growth of some bacteria, the concentrations used for sweetening purposes are rather low. Therefore, the benificial effect of the use of stevioside would rather be due to the substitution of sucrose in the food by a non-cariogenic substance. 

In Japan, the largest market for the S. rebaudiana sweeteners to date, three different forms of stevia sweetener products are commercially available, namely, stevia extract , sugar-transferred stevia extract , and rebaudioside A-enriched stevia extract . Stevia extract is a powder or granule made by several industrial steps and standardized so as to contain more than 80% of steviol glycosides, inclusive of dulcoside A (3-5%), rebaudioside A (20-25%), rebaudioside C (5-10%), and stevioside (50-55%) [31]. Sugar-transferred stevia extract is made by... 

Sucrose Glucose Inverted sugar Corn syrup High-fructose corn syrup (isoglucose) Honey Fructose Maltitol Sorbitol Isomalt Xylitol Mannitol Trehalose Tagatose Isomaltulose Acesulfame-K Aspartame Cyclamate Saccharine Sucralose Neohesperidin DC Thaumatine Stevia extract Lo-Han extract... 

The LD50 of orally administered stevia extract in rats is 17 g/kg (Mitusuhashi 1976). The LD50 of the compound stevioside orally administered to mice, rats, and hamsters could not be determined at doses up to 15 g/kg (Toskulkao et al. 1997). 

At the present time, Stevia rebaudiana extract accounts for 40 % of the sweetener market in cotmtries such as Japan, Korea, and Malaysia. Stevia extract and stevioside are officially approved as food additives in Brazil, Korea, Japan, and United States [68, 69]. Japan was the first country in Asia to market stevioside as a sweetener in food and dmg industries. 

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