High pressure vegetables

Sanchez-Moreno C, Cano MP, De Ancos B, Plaza L, Olmedilla B, Granado F and Martin A. 2004b. Consumption of high-pressurized vegetable soup increases plasma vitamin C and decreases oxidative stress and inflammatory biomarkers in healthy humans. J Nutr 134(11) 3021—3025. 

Numerous high pressure Hquid chromatographic techniques have been reported for specific sample forms vegetable oHs (55,56), animal feeds (57,58), seta (59,60), plasma (61,62), foods (63,64), and tissues (63). Some of the methods requite a saponification step to remove fats, to release tocopherols from ceHs, and/or to free tocopherols from their esters. AH requite an extraction step to remove the tocopherols from the sample matrix. The methods include both normal and reverse-phase hplc with either uv absorbance or fluorescence detection. AppHcation of supercritical fluid (qv) chromatography has been reported for analysis of tocopherols in marine oHs (65). 

Hajare and others 2007), and high-pressure processing induce small or no losses of carotenoids in intact fruits and vegetables and their juices and purees. 

Mclnerney JK, Seccafien CA, Stewart CM and Bird AR. 2007. Effects of high pressure processing on antioxidant activity, and total carotenoid content and availability, in vegetables. Innov Food Sci Emerg Technol 8 543-548. 

Basak, S. and Ramaswamy, H.S. 1998. Effect of high pressure processing on the texture of selected fruits and vegetables. J. Texture Stud. 29, 587-601. 

Butz, P., Edenharder, R., Fernandez Garcia, A., Fister, H., Merkel, C., and Tauscher, B. (2002). Changes in functional properties of vegetables induced by high pressure treatment. Food Res. Int. 35, 295-300. 

Yorio, N. C., Mackowiak, C. L., Wheeler, R. M., Sager, J. C. (1995b). Vegetative growth of potato under high-pressure sodium, high-pressure sodium SON-AGRO, and metal halide lamps. HortScL, 30, 374-376. 

The interest in mass transfer in high-pressure systems is related to the extraction of a valuable solute with a compressed gas. This is either a volatile liquid or solid deposited within a porous matrix. The compressed fluid is usually a high-pressure gas, often a supercritical fluid, that is, a gas above its critical state. In this condition the gas density approaches a liquid—like value, so the solubility of the solute in the fluid can be substantially enhanced over its value at low pressure. The retention mechanism of the solute in the solid matrix is only physical (that is, unbound, as with the free moisture), or strongly bound to the solid by some kind of link (as with the so-called bound moisture). Crushed vegetable seeds, for example, have a fraction of free, unbound oil that is readily extracted by the gas, while the rest of the oil is strongly bound to cell walls and structures. This bound solute requires a larger effort to be transferred to the solvent phase. 

Later, Timson and Short started systematic experiments to test the resistance of bacterial spores, and tried to inactivate them completely to obtain a total sterilization. These authors studied the behaviour of spores under a high-pressure treatment with a long residence time at constant pressure in a range of temperature between - 25°C and 95°C. They noted the high insensitivity to pressure of the spores compared to vegetative forms [8]. 

Chase, G.W. Jr., Akoh, C.C., and Eitenimiller, R.R. 1994. Analysis of tocopherols in vegetable oils by high-pressure liquid chromatography Comparison of fluorescence and evaporative lightscattering detection. J. Am. Oil. Chem. Soc. 71 877-880. 

W van Haver. Determination of carbendazim and thiophanate-methyl residues in some vegetables and fruits by high pressure liquid chromatography. Z Lebensm Unters Forsch 172 1-3, 1981. 

Instant whipped cream is based on the same foam-stabilizing principles but is packaged as a liquid (emulsion) and a gas under very high pressure in an aerosol can (see the footnote to Section 15.5). When the can s valve is released, the tremendous gas expansion through a fine orifice drives the formation of the foam topping. In non-dairy instant whipped topping products the cream is replaced by vegetable oil, water, and a number of emulsifiers, stabilizers, and preservative. 

Samples containing 150 g of 500 ppm acids were also prepared using 3% added sodium chloride in the 90/10 oil/water blend, water, and vegetable oil as the microwave medium. These samples were heated 0, 1, 2, and 3 minutes in the microwave. Changes in the acid concentration were determined by high pressure liquid chromatography with an organic acid column and an aqueous mobile phase. 

Until now, oil-phospholipid mixtures, raw seed oils, aromatic vegetable oils, essential oils aqueous solutions and aqueous dispersions have been sprayed and extracted with supercritical C02 in the high pressure spraying apparatus (Figurel). For instance aqueous roasted coffee extract was sprayed with CO2 in order to rise concentration for posterior production of instant powder. Due to low process pressures (under 20 MPa) and increased... 

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