Humans are born with a preference for foods that have a sweet taste. Scientists believe that our ‘sweet tooth’ is an evolutionary advantage since non-toxic foods tended to be sweet. For centuries, worldwide, this desire drove people to seek out sweet foods and ingredients in nature, including honey, maple syrup, sugar cane, sugar beets, sweet corn, agave, fruit, and fruit juices.
Today, the desire for a sweet taste has not changed, but the modern lifestyle has. There are fewer opportunities to be physically active and more occasions to eat and drink. As energy expenditure has diminished, so have the daily energy calorie requirements, resulting in the need to consume fewer calories to manage weight.
Overweight and obesity have become a global public health issue for both adults and children. While there is no one simple solution, it is well accepted by experts that diet does play an important role, says Priscilla Samuel, PhD, director, Global Stevia Institute and Scientific & Regulatory Affairs, PureCircle.
Reducing calorie intake can help prevent and better manage these health issues, which has led consumers to look for alternatives to full calorie traditional sweeteners such as sugar, honey, high fructose corn syrup, just to name a few. Despite the emergence of these sweet substitutes, consumers still express preference for a natural source with few or zero calories.
This is especially true for the rising number of consumers who, with a growing awareness of the importance of health despite not being diagnosed with any particular health condition, are actively seeking naturally sourced ingredients over processed ones in the search for healthier foods.
Stevia, extracted from the leaves of stevia rebaudiana Bertoni plants, can aide in providing a sweet solution for people who desire the sweet taste yet not the additional calories. Foods made with stevia sweetener gives consumers the opportunity to consume foods with a sweetener that is naturally sourced, and, at the same time better manage their calorie and sugar intakes.
This plant-based sweetener has been used as a natural origin, sweet substitute and flavour around the globe for centuries, and can therefore be used by manufacturers as a functional ingredient.
Originally grown in Paraguay, stevia is a plant native to South America and is in the sunflower family. Indigenous people first used the stevia leaves more than 200 years ago to sweeten beverages or chewed them for the sweet taste. Japan was the first to commercial adopt stevia as a mainstream sweetener in the 1970s.
In recent years, the demand for zero-calorie sweetness from a natural source has supported stevia’s increased use in foods and beverages. Through an evolution of stevia leaf cultivation, improved sustainability in harvesting and production, and more precise herbal extraction, great tasting stevia can now be grown on a commercial scale.
Today, stevia can be grown in your own garden and is mainly cultivated in Paraguay, Kenya, China and the United States. Stevia is grown by natural, conventional plant breeding methods such as cross-pollination and is non-genetically modified.
So what is it about stevia that makes it a potential super functional ingredient for manufacturers to use in their products?
More Sweetness, Less Calories
Similar to other plant ingredients such as sugar, stevia is extracted from the stevia plant into a powdered sweetener form. The extraction process involves steeping the dried leaves of the plant, like a tea, and then separating and purifying the best tasting sweet compounds scientifically known as steviol glycosides.
There are many steviol glycosides naturally present in the stevia leaf, but eleven steviol glycosides are typically focused on due to their abundance, and each steviol glycoside has a particular taste profile and sweetness intensity. Purified stevia leaf extracts can contain one steviol glycoside or several different glycosides, which can be up to 400 times sweeter than sucrose.
Unlike sucrose or other sugars however, the sweetness from stevia comes without the accompanying calories. It can therefore fit into a healthy lifestyle as a natural-origin replacement for sweet calories. This is because steviol glycosides are poorly absorbed in the body and pass through the body without effect.
In the colon, gut bacteria release steviol from the steviol glycosides, which is then processed in the liver into steviol glucuronide, and removed from the body in the urine. Research confirms that there is no accumulation of steviol glycosides or any component or by-product of steviol glycosides in the body.
Most recently, stevia leaf extract has also been found to promote tooth health.
With these benefits in mind, stevia can be part of the healthy lifestyle and part of a healthy diet. According to Dr Samuel, consumers are actively looking for ways to help them choose healthy diets and ways to better manage their weight or prevent weight gain, and reduced calorie foods with stevia as a sweetener can offer them a way to do this with a sweetener that is of natural origin that can be consumed by both children and adults.
Certified For Safety
High purity stevia leaf extract, which contains 95 percent or greater steviol glycoside content and is approved for use in food and beverages around the world, is often referred to as stevia, stevia extracts, purified stevia leaf extracts, high purity stevia, or rebiana. Only high purity stevia extracts meeting this specification are approved by the Joint Food and Agricultural Organisation/World Health Organisation Expert Committee on Food Additives (JECFA) and many other regulatory agencies for use in foods and beverages.
JECFA recognises the following nine steviol glycosides for use in foods and beverages: Rebaudiosides (or Reb) A, B, C, D, and F; Stevioside, Rubusoside, Dulcoside A, and Steviol Bioside. A combination of these sweeteners may contribute to the 95 percent or more steviol glycoside content required to meet the JECFA specification.
Ongoing innovation shows the potential to identify and purify additional sweet steviol glycosides occurring naturally in the stevia leaf. However, it is important that manufacturers bear in mind that crude stevia extract and the whole leaves from the stevia plant do not have the same regulatory approval as purified stevia extract.
Regarding high purity stevia extract, all major global regulatory organisations, including the JECFA, the European Food Safety Authority (EFSA), the US Food and Drug Administration (FDA), and Food Standards Australia New Zealand (FSANZ), have determined it to be safe for use by the whole family, including children and pregnant women.
High purity stevia extract is also safe for those with diabetes. It has no effect on blood glucose levels and contributes no carbohydrate or glycemic load (a measure of the effect of a carbohydrate on blood sugar) so it can help people with diabetes enjoy sweetness while managing dietary carbohydrates. EFSA, JECFA, and the FDA recognise stevia as safe for people with diabetes.
In addition, high purity stevia leaf extract is non-carcinogenic and no allergies have been associated with its use in food and beverages.
Today, stevia has been approved for use in more than 100 countries around the world. Also, as of November 2015, both India and Gulf Cooperation Council (GCC) countries have finalised their approvals for the use of stevia in foods and beverages, says Dr Samuel. This makes the opportunity for manufacturers to create reduced calorie and reduced sugar foods with naturally-sourced stevia even greater.
On top of health benefits and guaranteed safety, stevia is also an ingredient that does not cause detrimental environmental impact. Stevia farming, extraction and purification require less water, land, and energy than other naturally sourced sweet ingredients, and is therefore a sustainable source of sweetness.
In communities around the world, stevia farming does not replace food crops, but instead provides the opportunity for farmers to diversify crops so that they have more variety to rely on for income. Stevia farming has become an attractive way to expand job opportunities and wages in many countries. As it can be used in a wide variety of product applications, the interest in stevia is growing around the world and can be observed by the increased growth launches of foods and beverages with stevia.