Paprika fractionation

Coenen et al. [60,61] proposed a two-step extraction for the separation of pungent compounds and carotenoid fractions. Aroma- and pungent components were recovered at 120 bar and 40°C, and the paprika residue was re-extracted at 320 bar and 40°C to recover carotenoids. The solubility of capsaicin in carbon dioxide was relatively low at a pressure of 120 bar, so a great amount of solvent (for example 130 kg of CO2 per kg of paprika) was needed to recover the aroma components totally. The extraction time was 6.5 hour. In the separator the pressure was 56 bar and the temperature was 45°C. The orange, paste-like extract recovered in the first step was extremely pungent in taste. It contained water, and the yield was about 15%. In the second step, a relatively great amount of CO2 (approximately 50 kg/kg) was needed to recover the carotenoids in quantitative yield. The extraction time was 4 hours. The dark red, liquid colour-concentrate is without capsaicinoids. The yield was 2.5%. 

As can be seen from Fig. 9.6-10 low pressure gives a poor yield, especially of capsanthin, the coloured fraction of paprika. The colour value is only about 1,370 ASTA (54,800 CU), or about 48% of initial capsanthin content. A higher extraction pressure like 500 bar allows a depleting yield of capsanthin. 

Fractionation of Paprika. Since there are so many extractable components in paprika, it helps to simplify the analysis by being somewhat selective during the extraction. The solvent power of the fluid will have the most impact on the selective extraction of certain classes of compounds from the sample. Selective extractions were obtained by extracting the sample multiple times at different densities, commonly called density stepping or fractionation (as discussed by W.S. Miles at the Pittsburgh Conference in New York City 1990, paper 543). 

Carotene complexes might restore electrical conductivity [12] in several subcellular compartments. Recently, carotene-containing paprika extracts were fractionated by Motohashi and his coworkers and some of the fractions could apparently reverse the MDR of tumor cells [13]. 

Many fractions of red and green paprika extracts had reversed the MDR of cancer cells [13,16] in our previous experiments. The effectiveness of hexane and acetone fractions of paprika on the ABC transporter responsible for MDR reversal, made it worth studying the effects of carotenoids and flavonoids on the drug accumulation of cancer cells. 

HORNERO-MENDEZ D and MINGUEZ-MOSQUERA MI. 2001. Rapid spectro-photometric determination of red and yellow isochromic carotenoid fractions in paprika and red pepper oleoresins. J. Agric. Food Chem. 49 3584-3588. 

In 2005, our group examined on their carotenoid fractions from red paprika, Valencia orange peel and the peels of Golden delicious apple. 

Carotenoid composition of paprika fruit is shown in fig.2. The fruit distributed mono- and di-fatty acid esters of capsanthin and capsorubin in addition to free pigments, GLC analysis of fatty acids esterified with the carotenoid pigment indicated that capsanthin and capsorubin esterified mainly with saturated fatty acid to form diesters. Although unsaturated fatty acids are predominant in paprika, they were detected only with the fraction of capsanthin monoesters. 

Total extraction has the target to obtain the highest possible yield of soluble substances, whereas a single separation results in a so-called total extract, hut multiple separations allow fractioned products. Typical examples are the extraction of spices, herbs, and hops. One likes to obtain the exhaustive lead substances as a-acids from hops or piperine from pepper, or gingeroles from ginger, or carotinoids from paprika and so on on the one hand and the corresponding aromas on the other. The extraction residue from the extractor is mostly without any value, hut can sometimes be used as fertilizer basis or animal food addition. 

Carotene, m.p. 185°, [a] = 0°, resembles the a-form, but is slightly less soluble. -Carotene occurs almost pure in spinach and in red pepper (paprika). The carotene fraction from palm-nut oil contains about 60-70 per cent, of the jS-form, the rest being a-carotene. 

Lipid fractions (oleoresins), in which the monoglyceride content is somewhat higher (up to 2-3 wt%), have been explored and used for some applications. Many of the oleoresins extracted from fruits, flowers, spices, leaves, etc. consist of various triglycerides, nonsaponifiable fats (waxes), and monoglyceride derivatives. These fractions are sometimes self-emulsifiable and can form in situ water-in-oil emulsions. Such oleoresins from tomato, rosemary, sage, paprika, etc. can provide other functional properties. 

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