Impact of different cooking methods on food quality: Retention of ...

332 S. Bernhardt, E. Schlich / Journal <strong>of</strong> Food Engineering 77 (2006) 327–333
clear that boiling leads to high losses while stewing,
steaming, microwave <strong>cooking</strong> and even pressure steaming
cause only small losses (Loh, 2004). Losses <strong>of</strong> minerals
during <strong>cooking</strong> are not caused by destruction but
only by leaching into the <strong>cooking</strong> water (Miller, 1996).
Leaching is also the main reason for the high losses <strong>of</strong>
ascorbic acid during <strong>cooking</strong>. Different studies have
found an decrease <strong>of</strong> ascorbic acid by boiling up to
75% (Gould & Golledge, 1989; Petersen, 1993; Schnepf
& Driskell, 1994).
4. Conclusions
By comparison <strong>of</strong> the results <strong>of</strong> b-carotene and atocopherol
it seems that similarities in localisation lead
to a similar behaviour during <strong>cooking</strong>.
Cooking a green fresh vegetable promotes the release
<strong>of</strong> lipophilic vitamins. Whereas in a red vegetable fruit
respectively in the frozen vegetables which have passed
a blanching step a decrease or no change occurs.
For b-carotene it is known since longer that <strong>cooking</strong>
can increase the extractability and thereby probably improves
the bioavailability <strong>of</strong> b-carotene from the vegetable
matrix.
Whereas for a-tocopherol it is still unclear how the
food matrix influences absorption and bioavailability.
The given results let assume that <strong>cooking</strong> leads also to
a better availability <strong>of</strong> a-tocopherol from sources which
are difficult to access.
Between the single <strong>cooking</strong> <strong>methods</strong> no significant
differences can be observed if only the results for the
lipophilic vitamins are considered. But if there is also
paid attention in preserving hydrophilic compounds like
ascorbic acid and minerals boiling should be avoided in
favour <strong>of</strong> a <strong>cooking</strong> method with less water.
References
Arango, Y., & Heise, K. P. (1998). Localization <strong>of</strong> a-tocopherol
synthesis in chromoplast envelope membranes <strong>of</strong> Capsicum annuum.
I. Fruits. Journal <strong>of</strong> Experimental Botany, 49, 1259–1262.
Bognár, A. (1989). Untersuchungen über den Einfluss der Temperaturund
Verpackung auf den Genuss- und Nährwert von frischem
Gemüse und Obst bei der Lagerung im Kühlschrank. Ernährungs
Umschau, 36, 254–263.
Booth, V. H. (1963). a-Tocopherol, its co-occurrence with chlorophyll
in chloroplasts. Phytochemistry, 2, 421–427.
Booth, V. H., & Bradford, M. P. (1963). The effect <strong>of</strong> <strong>cooking</strong> on atocopherol
in vegetables. International Journal <strong>of</strong> Vitamin Research,
33, 276–277.
Bramley, P. M., Kafatos, A., Kelly, F. J., Manios, Y., Roxborough, H.
E., Schuch, W., et al. (2000). Review vitamin E. Journal <strong>of</strong> the
Science <strong>of</strong> Food and Agriculture, 80, 913–938.
Brubacher, G. (1966). Über den Vitamin E-Gehalt einiger Nahrungsmittel.
Internationale Zeitschrift für Vitaminforschung, 38,
409–415.
Castenmiller, J. J. M., & West, C. E. (1998). Bioavailability and
bioconversion <strong>of</strong> carotenoids. Annual Reviews <strong>of</strong> Nutrition, 18,
19–38.
de Pee, S., West, C. E., Permaesih, D., Muhilal, S. M., & Hautvast, J.
(1998). Orange fruit is more effective than are dark-green, leafy
vegetables in increasing serum concentrations <strong>of</strong> retinol and bcarotene
in schoolchildren in Indonesia. American Journal <strong>of</strong>
Clinical Nutrition, 68, 1058–1067.
Deming, D. M., Baker, D. H., & Erdman, J. W. (2002). The
relative vitamin A value <strong>of</strong> 9-cis b-carotene is less and that <strong>of</strong>
13-cis b-carotene may be greater than the accepted 50% that <strong>of</strong>
all-trans b-carotene in gerbils. Journal <strong>of</strong> Nutrition, 132,
2709–2712.
Deming, D. M., Teixeira, S. R., & Erdman, J. W. (2002). All-trans-bcarotene
appears to be more bioavailable than 9-cis or 13-cis-bcarotene
in gerbils given single oral doses <strong>of</strong> each isomer. Journal <strong>of</strong>
Nutrition, 132, 2700–2708.
Dietz, J. M., Kantha, S. S., & Erdman, J. W. (1988). Reversed phase
HPLC analysis <strong>of</strong> a- and b-carotene from selected raw and cooked
vegetables. Plant Foods for Human Nutrition, 38, 333–341.
DIN EN 12823-2, (2000). Bestimmung von Vitamin A mit Hochleistungs-Fflüssigkeits-chromatographie.
Bestimmung von b-Carotin
(Teil 2). Deutsches Institut für Normung e.V. Berlin: Beuth Verlag.
Eitenmiller, R. R., & Landen, W. O. (1999). Vitamin analysis for the
health and food sciences (pp. 223–270). Boca Raton, London, New
York, Washington: CRC Press.
Erdman, J. W., Poor, C. L., & Dietz, J. M. (1988). Factors affecting the
bioavailability <strong>of</strong> vitamin A, carotenoids, and vitamin E. Food
Technology, 42, 214–221.
Esterbauer, H., & Hayn, M. (1997). Vitamin E. In H. K. Biesalski
(Ed.), Vitamine: physiologie, pathophysiologie, therapie (pp. 41–58).
New York: Thieme Stuttgart.
Franke, W. (1997). Nutzpflanzenkunde (6. neubearb. Aufl). New York:
Thieme, Stuttgart.
Gould, M. F., & Golledge, D. (1989). Ascorbic acid levels in
conventionally cooked versus microwave oven cooked frozen.
Food Sciences and Nutrition, 42F, 145–152.
Hart, D., & Scott, K. J. (1995). Development and evaluation <strong>of</strong> an
HPLC method for the analysis <strong>of</strong> carotenoids in foods, and the
carotenoid content <strong>of</strong> vegetables and fruit commonly consumed in
the UK. Food Chemistry, 54, 101–111.
Herrmann, K. (1994). Inhaltsst<strong>of</strong>fe der Kohlarten. Teil 1. Industrielle
Obst- und Gemüseverwertung, 79, 244–252.
Herrmann, K. (1996). Gemüse und Gemüseerzeugnisse. In F. Timm &
K. Herrmann (Eds.), Tiefgefrorene Lebensmittel (2. Aufl., pp. 183–
202). Berlin: Blackwell Wiss Verlag.
Howard, L. A, Wong, A. D., Perry, A. K., & Klein, B. P. (1999). b-
Carotene and ascorbic acid retention in fresh and processed
vegetables. Journal <strong>of</strong> Food Science, 64, 929–936.
IZ-Lufa-ITL, (1999). Bestimmung von Vitamin C (Ascorbinsäure).
Kesel, A. B., Junge, M. M., & Nachtigall, W. (1999). Einführung in die
angewandte Statistik für Biowissenschaftler. Basel, Bosten, Berlin:
Birkhäuser.
Lessin, W. J., Catigani, G. L., & Schwartz, S. J. (1997). Quantification
<strong>of</strong> cis–trans-isomers <strong>of</strong> provitamin A carotenoids in fresh and
processed fruits and vegetables. Journal <strong>of</strong> Agriculture and Food
Chemistry, 45, 3728–3732.
Lichtenthaler, H. K. (1969). Zur Synthese der lipophilen Plastidenchinone
und Sekundärcarotinoide während der Chromoplastenentwicklung.
Berichte der Deutschen Botanischen Gesellschaft, 82,
483–497.
Loh, S., (2004). Bewertung des Einflusses verschiedener Garverfahren
auf die sensorische und ernährungsphysiologische Qualität von
frischen und TK-Gemüsen anhand ausgewählter Parameter. Cuvillier,
Göttingen.
Loh, S., & Schlich, E. (2003). Einfluss verschiedener Garverfahren auf
die cis-/all-trans-ratio von b-Carotin in Gemüse. Proceedings <strong>of</strong> the
German Nutrition Society, 5, 69.
Miller, D. (1996). Minerals. In O. R. Fennema (Ed.), Food chemistry
(3rd ed.). New York: Marcel Dekker.