Grape/grapes extraction

Grape color extract Grapefruit Grapefruit juice... 

Grape color extract is used to color such products as bakers jams, non-standard jellies and preserves, sherbets, ices, pops, raspberry, grape and strawberry yogurts, gelatin desserts, canned fmit, fmit sauces, candy and confections, and bakery fillings and toppiags. Typical use concentrations are 0.05 to 0.8%, based on the weight of the finished product. 

Typically, grape skin extract has a specific gravity of 1.13 g/mL at 20°C, a solids content of 28—32° Brix (=t3°), a pH of 3.0, and a color strength as anthocyanin of about 1.25% (as measured at 520 nm ia pH 3.0 citrate buffet). Grape skin extract is also available as spray-dried powders with color values three to four times those of the liquid. The properties and uses of grape skin extract ate similar to those of grape color extract. 

Revilla, 1. et al.. Identification of anthocyanin derivatives in grape skin extracts and red wines by liquid chromatography with diode array and mass spectrometric detection, J. Chromatogr. A, 847, 83, 1999. 

Ruberto, G. et al.. Polyphenol constituents and antioxidant activity of grape pomace extracts from five Sicilian red grape cultivars. Food Chem., 100, 203, 2007. 

Nakamura, Y., Tsuji, S., and Tonogai, Y, Analysis of proanthocyanidins in grape seed extracts, health foods and grape seed oils, J. Health Set, 49, 45, 2003. 

Anthocyanins, grape color extract, grape skin extract E 163 Yes... 

Revilla E and Ryan JM. 2000. Analysis of several phenolic compounds with potential antioxidant properties in grape extracts and wines by high-performance liquid chromatography—photodiode array detection without sample preparation. J Chromatogr 881(1-2) 461 169. 

Tomaino A, Cristani M, Cimino F, Speciale A, Trombetta D, Bonina F and Saija A. 2006. In vitro protective effect of a Jacquez grapes wine extract on UVB-induced skin damage. Toxicol Vitr 20(8) 1395-1402. 

Grape color extract GMP for non-beverage foods E163 0-2.5... 

Fig. 2.61. Separation of grape seed extract (a) and grape seed extract spiked with mixture of eight compounds (b) using optimized conditions. Chromatographic conditions are discussed in the text. Peak identification 1 = 2-phenylethanol 2 = vanillin 3 = ferulic acid 4 = protocatechoic acid 5 = caffeic acid 6 = gallic acid 7 = catechin 8 = epicatechin. Reprinted with permission from A. Kamangerpour et al. [167].

The optimum conditions for the MS detection of anthocyanin derivatives have also been intensively studied. Grape skin extract was prepared by macerating skins with methanol-formic acid (95 5) for three days changing the extracting agent each day. The combined extracts were evaporated and diluted with water. RP-HPLC measurements were carried out in an ODS column (150 X 4.6 mm i.d. particle size 5 /an) at 30°C. The solvents were water-formic acid (90 10, v/v, A) and methanol-water-formic acid (45 45 10, v/v, B). The gradient was from 35 to 95 per cent B in 20 min to 100 per cent B in 5 min final hold... 

A. Kamangerpour, M. Ashraf-Khorassani, L.T. Taylor, H.M. McNair and L. Charida, Supercritical fluid chromatography (SFC) of polyphenolic compounds in grape seed extract. Chromatographia 55 (2002) 417 -21. 

Methods used for the detection of PAs in cmde or partially purified extracts can also be adapted for post-column analysis after fractionation (see below). Direct quantitative analysis of PAs in crude grape phenolic extracts is often impossible due to the complex sample matrix. Thus, fractionation or purification is often necessary before analysis. The Folin-Ciocalteu and Pmssian Blue assays are widely used for the quantification of total polyphenols in plants [27,28]. These methods are not specific for PAs due to the reaction of other phenolic compounds with these reagents. 

Dietary intervention with crude MegaNatural-AZ grape seed extract significantly reduced (by 30-50%) Alzheimer s disease-type cognitive deterioration in mice by prevention of amyloid formation in the brain [8]. However, it is essential to determine which components of the extract exhibited bioactivity in the transgenic... 

Kohler N, Wray V, Winterhalter P (2008) Preparative isolation of procyanidins from grape seed extracts by high-speed counter-current chromatography. J Chromatogr A 1177 114-125... 

Krueger, C.G. et al. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of polygalloyl polyflavan-3-ols in grape seed extract, J. Agric. Food Chem., 48, 1663, 2000. 

---