View source for Biology:Styrian oil pumpkin

{{Short description|Cultivar of pumpkin}}
{{Infobox cultivar
| name = ''Cucurbita pepo ''var'' styriaca''<br/>'Styrian oil pumpkin'
| image = Steirischer Ölkürbis Feld Allhaming 20200911b.jpg
| image_caption = Field with Styrian oil pumpkin
| species = ''[[Biology:Cucurbita pepo|Cucurbita pepo]]''
| genus = Cucurbita
| cultivar = Styrian oil
| origin = 
| marketing_names = 
}}
The '''Styrian oil pumpkin''' (''[[Biology:Cucurbita pepo|Cucurbita pepo]]'' var. ''styriaca''), also known as the '''Styrian pumpkin''', is a variety of the common [[Biology:Pumpkin|pumpkin]] (''Cucurbita pepo pepo'') which is cultivated to produce pumpkin seed oil.

The young fruits are dark green, turning yellow-orange upon ripening. They have a [[Biology:Mutation|mutation]] resulting in the loss of the [[Biology:Lignin|lignified]] seed shell. Approximately 2.5&nbsp;kg of  seed, the equivalent or 30–40 pumpkins, produce 1 liter of pumpkin seed oil. On average, a ripe oil pumpkin weighs between 8 and 10 kilograms.<ref name="dx.doi.org">{{Cite journal |last1=Fruhwirth |first1=Gilbert O. |last2=Hermetter |first2=Albin |date=November 2007 |title=Seeds and oil of the Styrian oil pumpkin: Components and biological activities |url=http://dx.doi.org/10.1002/ejlt.200700105 |journal=European Journal of Lipid Science and Technology |volume=109 |issue=11 |pages=1128–1140 |doi=10.1002/ejlt.200700105 |issn=1438-7697|doi-access=free }}</ref>

== History ==
The Styrian oil pumpkin is of relatively recent origin. Its crucial mutation, resulting in distinctive dark green seeds, was first recorded between 1870 and 1880. This accidental natural mutation is the result of an alteration in a single [[Biology:Dominance (genetics)|recessive gene]].<ref>{{Cite journal |last1=Stuart |first1=Susan G. |last2=Loy |first2=J. Brent |date=December 1983 |title=Comparison of Testa Development in Normal and Hull-Less Seeded Strains of Cucurbita pepo L. |url=http://dx.doi.org/10.1086/337402 |journal=Botanical Gazette |volume=144 |issue=4 |pages=491–500 |doi=10.1086/337402 |s2cid=85263638 |issn=0006-8071}}</ref> The soft  seed coat made efficient oil extraction possible and enabled the production of the renowned Styrian pumpkin seed oil, a regional specialty in [[Place:Southeast Europe|southeastern Europe]]. The oil's history is closely tied to the economic and cultural dynamics of the area.<ref name="dx.doi.org"/> Today, [[Chemistry:Adulterant|adulteration]] of Styrian pumpkin seed oil is considered professional fraud. Cheaper edible oils such as [[Chemistry:Sunflower oil|sunflower oil]], [[Biology:Rapeseed oil|rapeseed oil]], or soybean oil are common adulterants.<ref>{{Cite journal |last1=Wenzl |first1=Thomas |last2=Prettner |first2=Elke |last3=Schweiger |first3=Klaus |last4=Wagner |first4=Franz S |date=October 2002 |title=An improved method to discover adulteration of Styrian pumpkin seed oil |url=http://dx.doi.org/10.1016/s0165-022x(02)00108-2 |journal=Journal of Biochemical and Biophysical Methods |volume=53 |issue=1–3 |pages=193–202 |doi=10.1016/s0165-022x(02)00108-2 |pmid=12406602 |issn=0165-022X}}</ref>

== Distribution ==
It is traditionally cultivated industrially in parts of the former [[Place:Austria-Hungary|Austro-Hungarian Empire]], in present-day south-eastern Austria (Styria), north-eastern Slovenia (Styria, Prekmurje), central [[Place:Transylvania|Transylvania]] and the Orăștie-Cugir region of Romania, north-eastern Croatia (Međimurje), Vojvodina and neighbouring parts of Hungary. In these countries, the use of pumpkin seed oil in the diet is traditional. The Styrian oil pumpkin is also widespread in the far eastern part of Europe ({{wipe|Ukraine}}) and in {{wipe|Russia}}, North America, Mexico, {{wipe|India}} and {{wipe|China}}.

== Nutritional value ==
The oil's fatty acid profile, with [[Chemistry:Polyunsaturated fat|polyunsaturated fatty acids]] constituting approximately 45.6 ± 5%rel, surpasses [[Chemistry:Monounsaturated fat|monounsaturated]] (35.9 ± 10%rel) and [[Chemistry:Fatty acid|saturated fatty acids]] (18.5 ± 20%rel).<ref name="ReferenceA">{{Cite journal |last1=Fruhwirth |first1=Gilbert Otto |last2=Wenzl |first2=Thomas |last3=El‐Toukhy |first3=Rosemarie |last4=Wagner |first4=Franz Siegfried |last5=Hermetter |first5=Albin |date=June 2003 |title=Fluorescence screening of antioxidant capacity in pumpkin seed oils and other natural oils |url=http://dx.doi.org/10.1002/ejlt.200390055 |journal=European Journal of Lipid Science and Technology |volume=105 |issue=6 |pages=266–274 |doi=10.1002/ejlt.200390055 |issn=1438-7697}}</ref> [[Chemistry:Linoleic acid|Linoleic acid]], [[Chemistry:Oleic acid|oleic acid]], [[Chemistry:Palmitic acid|palmitic acid]], and [[Chemistry:Stearic acid|stearic acid]] dominate, collectively accounting for nearly 98% of the fatty acids present.<ref name="ReferenceB">{{Cite journal |last1=Murkovic |first1=M. |last2=Hillebrand |first2=A. |last3=Winkler |first3=J. |last4=Leitner |first4=E. |last5=Pfannhauser |first5=W. |date=May 1996 |title=Variability of fatty acid content in pumpkin seeds (Cucurbita pepo L.) |url=http://dx.doi.org/10.1007/bf01192866 |journal=Zeitschrift für Lebensmittel-Untersuchung und -Forschung |volume=203 |issue=3 |pages=216–219 |doi=10.1007/bf01192866 |pmid=8873459 |s2cid=158751 |issn=1431-4630}}</ref> Minimal traces of other fatty acids are also present.<ref name="ReferenceB"/>

High-quality pumpkin seed oil has γ-tocopherol with concentrations reaching 800&nbsp;mg/kg. This oil's [[Chemistry:Γ-Tocopherol|γ-tocopherol]] levels are higher than its [[Chemistry:Α-Tocopherol|α-tocopherol]] levels.<ref name="ReferenceA"/> The oil also contains [[Chemistry:Vitamin A|vitamin A]], [[Biology:Carotenoid|carotenoid]]s such as [[Chemistry:Lutein|lutein]] and [[Chemistry:Β-Carotene|β-carotene]], and several [[Chemistry:B vitamins|vitamin B]] compounds. Styrian pumpkin seed oil exhibits elevated levels of [[Chemistry:Sodium|sodium]], [[Chemistry:Potassium|potassium]], [[Chemistry:Magnesium|magnesium]], [[Chemistry:Calcium|calcium]], and [[Chemistry:Phosphorus|phosphorus]], with [[Chemistry:Selenium|selenium]] being detected.<ref>{{Cite journal |last1=Smrkolj |first1=Polona |last2=Stibilj |first2=Vekoslava |last3=Kreft |first3=Ivan |last4=Kapolna |first4=Emese |date=December 2005 |title=Selenium Species Determination in Selenium-Enriched Pumpkin (Cucurbita pepo L.) Seeds by HPLC-UV-HG-AFS |url=http://dx.doi.org/10.2116/analsci.21.1501 |journal=Analytical Sciences |volume=21 |issue=12 |pages=1501–1504 |doi=10.2116/analsci.21.1501 |pmid=16379394 |s2cid=23974291 |issn=0910-6340}}</ref>

The oil contains [[Chemistry:Phytosterol|phytosterol]]s, approximately 2–2.5 times more concentrated than in the seeds, with D7-sterols being predominant. Styrian pumpkin seed oil owes its dark green color and distinct aroma to compounds like protochlorophyll, protopheophytin, and carotenoids.<ref>{{Cite journal |last=Ellsworth |first=R.K. |date=February 1971 |title=Simple method for separation of milligram quantities of protochlorophyll a from seed oils in extracts of whole pumpkin seeds |url=http://dx.doi.org/10.1016/0003-2697(71)90448-9 |journal=Analytical Biochemistry |volume=39 |issue=2 |pages=540–542 |doi=10.1016/0003-2697(71)90448-9 |pmid=4324535 |issn=0003-2697}}</ref> The aroma, characterized by a nutty roast, results from a roasting process involving high temperatures of extended duration.<ref>{{Cite journal |last1=Matsui |first1=Toshiro |last2=Guth |first2=Helmut |last3=Grosch |first3=Werner |date=February 1998 |title=A comparative study of potent odorants in peanut, hazelnut, and pumpkin seed oils on the basis of aroma extract dilution analysis (AEDA) and gas chromatography-olfactometry of headspace samples (GCOH) |url=http://dx.doi.org/10.1002/(sici)1521-4133(199802)100:2<51::aid-lipi51>3.0.co;2-w |journal=Lipid - Fett |volume=100 |issue=2 |pages=51–56 |doi=10.1002/(sici)1521-4133(199802)100:2<51::aid-lipi51>3.0.co;2-w |issn=0931-5985|doi-access=free }}</ref> The oil also exhibits [[Biology:Antioxidant|antioxidant]] properties attributed to its [[Chemistry:Phenols|phenolic compounds]], which constitute up to 40% of the total antioxidant capacity.<ref name="ReferenceA" />

Although Styrian pumpkin seed oil contains significant amounts of antioxidants, the green pigments in the oil act make it light sensitive and shorten its [[Finance:Shelf life|shelf life]]. They are efficient sensitizers for light-induced fatty acid [[Chemistry:Redox|oxidation]] and, along with a high content of polyunsaturated fatty acids, make it susceptible to rancidity.<ref>{{Cite journal |last1=Li |first1=Wei |last2=Koike |first2=Kazuo |last3=Tatsuzaki |first3=Masaru |last4=Koide |first4=Atsushi |last5=Nikaido |first5=Tamotsu |date=2005-12-01 |title=Cucurbitosides F−M, Acylated Phenolic Glycosides from the Seeds of ''Cucurbita pepo'' |url=http://dx.doi.org/10.1021/np050328b |journal=Journal of Natural Products |volume=68 |issue=12 |pages=1754–1757 |doi=10.1021/np050328b |pmid=16378368 |issn=0163-3864}}</ref><ref>{{Cite journal |last1=Lankmayr |first1=Ernst |last2=Mocak |first2=Jan |last3=Serdt |first3=Katja |last4=Balla |first4=Branko |last5=Wenzl |first5=Thomas |last6=Bandoniene |first6=Donata |last7=Gfrerer |first7=Marion |last8=Wagner |first8=Siegfried |date=October 2004 |title=Chemometrical classification of pumpkin seed oils using UV–Vis, NIR and FTIR spectra |url=http://dx.doi.org/10.1016/j.jbbm.2004.04.007 |journal=Journal of Biochemical and Biophysical Methods |volume=61 |issue=1–2 |pages=95–106 |doi=10.1016/j.jbbm.2004.04.007 |pmid=15560925 |issn=0165-022X}}</ref>

== Cultivation, production and storage ==

=== Sowing ===
Styrian oil pumpkins are sown at appropriate soil temperature between mid to late April. It is sown into a seedbed of sandy, well-trained soil at a depth of 3–4&nbsp;cm with a row distance of 80&nbsp;cm. Heavy wet clay soils are not appropriate.<ref>{{Cite web |title=Praktiker-Tipps zu Mais, Hirse, Soja und Kürbis {{!}} Landwirtschaftskammer Steiermark |url=https://stmk.lko.at/praktiker-tipps-zu-mais-hirse-soja-und-k%C3%BCrbis+2400+2906678 |access-date=2023-12-01 |website=stmk.lko.at |language=de}}</ref> A planting density of 17,000 seeds per [[Hectare|hectare]] is appropriate. For organic farming 20,000 seeds per hectare should be sown for better competition against weeds.<ref name=":0">{{Cite web |last=saatbau |date=2020-04-24 |title=Was bei der Produktion von Ölkürbis zu beachten ist |url=https://www.saatbau.com/at/oelkuerbis-produktion/ |access-date=2023-12-01 |website=SAATBAU LINZ |language=de-DE}}</ref>

=== Fertilisation ===
The styrian oil pumpkin requires 150&nbsp;kg/ha of [[Chemistry:Nitrogen|Nitrogen]], 13.1&nbsp;kg/ha of Phosphorus, 124.5&nbsp;kg/ha of Potassium and 10&nbsp;kg/ha of Magnesium.<ref>{{Cite book |last=Carlen |first=Christoph |title=Grundlagen für die Düngung landwirtschaftlicher Kulturen in der Schweiz |publisher=Agroscope |year=2017 |location=Bern |pages=10/6 |language=German}}</ref>

=== Crop protection ===
A [[Engineering:Cultivator|cultivator]] or appropriate chemicals can be used to combat weeds. There are no known [[Biology:Fungicide|fungicide]]s with a significant effect in this culture. [[Biology:Insecticide|Insecticide]]s can have be significantly effective against [[Biology:Aphid|aphid]]s.<ref name=":0" /> The lack of a lignified seed shell makes it susceptible to soil-borne fungal diseases, increasing the risk of poor seed germination, especially in wet years. The pumpkin is also susceptible to fruit rot.

=== Harvest ===
The crop is harvested around September and October. It is ready when plant material is dead and the kernels are easily torn out of the fruit flesh.<ref name=":0" /> The pumpkins are harvested by first placing the plants into a swath. Then the pumpkins are picked and broken up. When opened, a harvester in the field removes the seeds using [[Physics:Centrifugal force|centrifugal force]]. The fruit flesh is discharged on the spot. Then the kernels can be transferred from the field.<ref>{{Cite web |title=Kürbiskernernte – Kirchwegergut |url=https://www.kirchwegergut.at/kuerbiskernernte/ |access-date=2023-12-01 |language=de-DE}}</ref>

=== Areas of cultivation and production ===
The climatic conditions in the areas of mid-Eastern Europe are suitable and, in particular, the average annual rainfall is often less than 800mm. World production of oil pumpkins is estimated at a total area of 600,000 hectares and a total yield of 200,000 tonnes of pumpkin seeds. Of this, approximately 120,000 tonnes of pumpkin seeds are produced in China. Huge quantities of these seeds also end up on the European market.<ref>{{Cite web |date=2011-02-04 |title=Oljne buče - od tradicionalne do profesionalne pridelave - Agrosaat |url=https://www.agrosaat.si/oljne-buce-od-tradicionalne-do-profesionalne-pridelave/ |access-date=2023-11-15 |language=sl-SI}}</ref> World consumption of pumpkin seeds is as follows:

* 80% (160,000 tonnes) is used in the baking industry,
* 10% (20,000 tonnes) is processed into oil,
* 10% (20,000 tonnes) is used for other uses.

== References ==
{{Reflist}}

[[Category:Cucurbita]]

{{Sourceattribution|Styrian oil pumpkin}}