Effect of Stevia rebaudiana Bert. Addition on the Antioxidant Activity of Red Raspberry (Rubus idaeus L.) Juices

Cecilia Bender,Dirk Rehmann,Helmut Weidlich,Karina Killermann

doi:10.3390/beverages4030052

Abstract

The demand for antioxidant-rich beverages is steadily expanding. At the same time, the possibility of manufacturing products with reduced sugar content, sweetened with natural ingredients, represents a decisive aspect of obtaining quality products with health benefits. Stevia rebaudiana Bertoni (stevia) is a natural sweetener that can help to control caloric intake and is also a good source of antioxidant compounds. The present study was designed to assess the feasibility of producing high-quality berry juices sweetened with dry-grinded stevia leaves or their crude extract. The effect of the stevia supplementation on the antioxidant activities of raspberry juices was determined at two different production steps by means of the Folin–Ciocalteu, the oxygen radical absorbance capacity (ORAC), and the cellular antioxidant activity (CAA) assays. The addition of stevia significantly increased the antioxidant activity of the juices and resulted in significantly higher ascorbic acid and total phenolic content. A positive correlation was observed between ORAC, CAA, and total phenolic values. These findings show that supplementation with stevia not only promotes a healthy diet by reducing sugar intake but may also enhance the antioxidant potential of the beverage.

Highlights

Rubus species are an excellent source of dietary phytochemicals and comprise berries with a high content of polyphenols
The extract was centrifuged for 10 min at 14,000× g, and 100 mL of the resulting supernatant were immediately added to 900 mL of raspberry juice
Most existing literature on the use of stevia is based on data regarding purified steviol glycosides, while few studies address the use of stevia leaves as an ingredient, and purified steviol glycosides, while few antioxidant studies address the in use of stevia leavesdescribes as an ingredient, and even fewer studies point out stevia’s potential foods

Summary

Introduction

Rubus species are an excellent source of dietary phytochemicals and comprise berries with a high content of polyphenols. Phenolic compounds and vitamin C have been implicated in the antioxidant capacity of fruits and derived beverages [2]. Contribute to the total antioxidant capacity of the raspberry [3,4]. Studies suggest that diets rich in plant polyphenols offer some protection against the development of cancers, cardiovascular diseases, diabetes, osteoporosis, and neurodegenerative diseases [5]. This embodies one of the main reasons for consumers’ growing interest in antioxidant-rich products, alongside an interest in products with reduced sugar content and of natural origin

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Conclusion