1. Lemon Juice + Chokeberry (5%) RESULTS AND DISCUSSION
COMPARISON OF NOVEL ANTIOXIDANT-RICH BEVERAGES BASED ON LEMON JUICE WITH DIFFERENT RED FRUITS
Gironés-Vilaplana A., González-Molina E., Moreno D.A., García-Viguera C.*
C.E.B.A.S. - C.S.I.C. Phytochemistry Lab. Food Science and Technology Dept.
Campus Universitario Espinardo – 25. Espinardo, Murcia, Spain
(Cristina García-Viguera)
INTRODUCTION
The aim of this work was to compare the nutritive and phytochemical composition of novel healthy beverages using lemon juice enriched with berry concentrates (elderberry, red grape, and chokeberry). Lemon (Citrus limon) juice, rich in vitamins, minerals and phenolic compounds with demonstrated health-promoting properties influencing different markers and risk factors of diseases such as diabetes, cardiovascular problems, obesity, and certain types of cancer is an interesting food matrix for functional beverages as well as suitable source for added-value products since overproduction and non-marketable produce represents a serious environmental problem of unused agrowaste. Natural colourants from berries including elderberry (Sambucus spp.), red grape (Vitis spp.), and chokeberry (Aronia melanocarpa) red fruits or berries are commonly used in food industry for the elaboration of juices, convenience beverages and dairy products, being all a great source of natural bioactive phytochemicals.
MATERIAL AND METHODS
Chokeberry (Aronia melanocarpa (Michx) Elliott; Fam. Rosaceae), elderberry (Sambucus nigra), and grape (Vitis vinifera) commercial concentrates were added (5% w:v) to freshly-prepared lemon juice (Citrus limon (L.) Burm. F. cv. “Fino”) (Fig. 1). The prepared mixtures (Table 1) were stored for 2 months in the dark at room temperature. The total phenolic compounds (Folin-Ciocalteu Reagent method), antioxidant activity (DPPH test), vitamin C (ascorbic acid + dehydroascorbic acid by HPLC-UV) contents and the anthocyanins (HPLC-DAD) present in the samples were determined. All the methods and techniques are reported elsewhere and followed according to González-Molina et al. [Ref ].
Table 1. Composition in the novel beverages (mg/100 mL juice) used as reference (initial value) for the storage study (2 months in the dark at room temperature).
Lemon Juice + Chokeberry (5%)
L.J. + Elderberry (5%)
L.J. + Grape (5%)
Total anthocyanins 27 37
4.3
Total phenolic compounds
242
155 39
Vitamin C 35
Antioxidant activity
10.96
8.17
4.13
Figure 1. Different fruits used in beverages: lemon plus: 1) Chokeberry; 2) Elderberry; 3) Grapes
RESULTS AND DISCUSSION
The red fruits (Fig. 2A) concentrates in berries control samples retained anthocyanins in higher levels than in the lemon mixtures. On the contrary, for the total phenolic compounds (FCR, Fig. 2B) the mixtures of red fruits with lemon were a better option, when compared to lemon juice. This result was also observed for the antioxidant activity (DPPH test, Fig. 2C), with higher retentions in the novel beverages than in the lemon juice. Elderberry and grape compounds showed some kind of protective effect on vitamin C (Fig. 2D), since this essential nutrient was lost in higher proportion in the lemon juice and in the mixtures with chokeberry concentrate.
From the ongoing work and the results here presented, we could conclude that the addition of a low percentage of elderberry, chokeberry or grape concentrate (5% w/v), effectively increase the lemon juice antioxidant properties and preservers the loss of total phenolic compounds, and in the case of grape and elderberry, their bioactive components may have a protective effect on the retention of vitamin C, in the novel beverages. Nevertheless, it should be taken into consideration that the final total concentration of bioactive compounds was higher in the mixtures with chokeberry, due to a much higher initial values, while grape presented very low proportions of these phytochemicals.
Figure 2.Percentage of loss of (A) Total Anthocyanins, (B) Total phenolic compounds, (C) Antioxidant Capacity and (D) Vitamin C, in beverages stored at 25ºC, in the dark (E: Elderberry; G: Grapes; C: Chokeberry; L: Lemon; LE: Lemon + Elderberry 5%; LG: Lemon + Grape 5%; LC: Lemon + Chokeberry 5%).
ACKNOWLEDGEMENTS
The authors wish to thank the Fundación Séneca (Murcia Regional Foundation for Science and Tehcnology – Regional Governement) for financial support (Research Projects AGR/12/FS/02 and 00594/PI/04). Part of this work was also funded by the Spanish Ministry of Science and Innovation (MICINN) through the CICYT projects (AGL /ALI).
REFERENCES
1. Gonzalez-Molina, E., Moreno, D. A., Garcia-Viguera, C. (2008). J. Agric. Food Chem. 56,
2. Gonzalez-Molina, E., Moreno, D. A., Garcia-Viguera, C. (2008). J. Agric. Food Chem. 56,
3. Gonzalez-Molina, E., Moreno, D. A., Garcia-Viguera, C. (2009). Sci. Hortic.- Amsterdam 120,
4. Gonzalez-Molina, E., Moreno, D. A., Garcia-Viguera, C. (2009). Food Chemistry 115,