POWDER FOOD SUPPLEMENT BASED ON GREEN COFFEE FRUIT EXTRACT AND HYDROLYZED COLLAGEN: DEVELOPMENT AND CHARACTERIZATION

Since 2015 our research group has been studying the production process of extracts, chemical composition, antioxidant efficacy and ingredients development based on whole green coffee fruit. Therefore, this study aimed to develop and characterize freeze-dried powder containing a mixture of fluid whole green coffee fruit extract (GCE) added of different proportions of hydrolyzed collagen. Firstly, we developed GCE by percolation method using whole green coffee fruits (GCF) and hydroethanolic solution (50:50, w/w) or ultrapure water (Millipore System, Billerica, MA, USA) as solvent. The GCF (Coffea canephora), produced by biodynamic farming, were kindly provided by Camocim Farm from Domingos Martins – ES. Then the total phenolic compounds of the two extracts was assessed by Follin-Ciocalteu method. In addition, we analyzed the total phenolic compounds of a commercial sample from FutureCeuticals, the Coffeberry Cascara (Momence, IL, USA), produced with whole cherry coffee fruit using water as solvent. The aqueous GCE showed a total phenolics compounds of 1.71  0.16 (mg EAG/g of GCE), while hydroethanolic GCE revealed the content of 6.36  0.37 (mg EAG/g of GCE) showing that the addition of ethanol into aqueous solvent significantly affected the total phenolic content in the GCE. On the other hand, the FutureCeutical extract, showed 0.46  0.04 (mg EAG/g of GCE) of the total content of phenolic compounds. After these results we choose the hydroethanolic solvent (50:50, w/w) to develop the GCE - hydrolyzed collagen freeze-dried powder. The experiment was carried out in triplicate, and 5% (A), 10% (B) and 25% (C) of hydrolyzed collagen were added in Falcon conical tubes and mixed with hydroethanolic GCE. The powders were characterized by color parameters (CIE L*, a*, b*), water activity (aW), pH, water solubility and total phenolic compounds. The samples shown closer colors between them, to perceptual lightness: L* 51.09  0.42 (A), 51.61  0.75 (B), and 51.97  1.15 (C), and also for red - green and blue – yellow color components (a* and b*). All samples showed a low aW, less than 0.3, typical of freeze-dried samples. The three powders showed an acid profile with pH of 5.66  0.02, 5.79  0.04, and 5.94  0.03, respectively. Furthermore, the samples showed a water solubility above 95 percent as required for food grade powders. A significant difference (p<0.05) was observed regarding the content of total phenolic compounds between hydrolyzed collagen - GCE freeze-dried powder samples. In the sample A we found 18.63  0.98, in B 15.15  1.05, and in C 10.11  1.02 (mg EAG/g) of phenolic compounds, showing that how greater the content of collagen added in GCE, minor is the total phenolic compound, it can be explained due the interaction among collagen proteins and phenolic acids present in GCE. Although the physicochemical characteristic proves suitable for a food grade powder, is known that phenolic acids and caffeine found in GCE can chelate collagen proteins, decreasing the bioavailability of both compounds, in front of that ours perspective is to study the in vitro bioavailability .