Information on Kogiku kaboch, or Kogiku pumpkin

Kogiku kaboch, or Kogiku pumpkin

Aidu traditional pumpkin


Major source:

Fukushima prefecture

Ishikawa prefecture

Fukui prefecture



It has been cultivated in the Iidera district of Monden, Aizuwakamatsu since the Edo period.


Harvest time:

 Middle July to early September


Dietary properties:

It is approximately 15 cm in diameter, and 500 to 800 grams in weight.

Its name originates from the top view similar to chrysanthemum.

Red thick skin and bright yellow flesh when it is ripe.

It has a soft and chewy texture and a simple tasting with light sweetness. The flavor of the broth easily soaks into it very well. Unlike other pumpkins, it does not easily boil down to pieces.

It is particularly good for “Washoku” such as Nimono, or food cooked in seasoned broth, Tempura, or deep-fried battered seafoods or vegetables, and steamed food.


Nutritional ingredients:

The contents of carbohydrates including dietary fiber and β-carotene as anti-oxidant vitamin in Kogiku Kabocha are higher than those in other Japanese pumpkin species.


Reference information of pumpkin

Origin: the Americas

History of cultivation in Japan:

It has been cultivated in the early 17th century since Portuguese introduced it into Japan in the middle 16th century.

Nutritional ingredients:

Vitamin A (β-carotene), E, K, B1, B2, B6, C, niacin, folic acid, and pantothenic acid

Minerals: potassium, calcium, magnesium, sodium, phosphorus, ferrum

Dietary fiber: Approximately 3000-4000 mg/100 g in western pumpkins

No cholesterol

Dietary properties:

Thick and tough skins contributes to long-term storage.

In Japan, people customarily eat pumpkins around in the winter solstice.

Cooking pumpkin with oil to Tempura or other fried food enhances the absorbance of β-carotene into body.

Anti-oxidant function of β-carotene accounts for enhancement of resistance to diseases such as flu.



Quantitative analyses of nutritional and functional ingredients of Kogiku pumpkin

1) Purpose of the experiment

Pumpkin belongs to the family Cucurbitaceae, of which various species are globally cultivated and taken. In general, it contains nutritional ingredients such as starch, proteins, and vitamins with relatively higher amount than other vegetables. It is a very important and highly nutritional agricultural product in winter. In this study, we undertook to determine quantitative analyses of nutritional ingredients and anti-oxidant substances such as β-carotene and vitamin C of Kogiku pumpkin cultivated in Inawashiro area in Fukushima prefecture.


2) Experimental procedures

Kogiku pumpkins on 21days post harvesting in Inawashiro was subjected to analyses of nutritional ingredients. In addition, the pumpkins on 36 and 111 days post harvesting in the same area were subjected to analyses of β-carotene and vitamin C according to the method of the Food Labeling Act enacted by the Cabinet Office in 2015.


3) Experimental result

Nutritional ingredients of Kogiku pumpkin in Inawashiro

Anti-oxidant substances of Kogiku pumpkin in Inawashiro


4) Discussion

Analyses of nutritional ingredients demonstrated that Kogiku pumpkins in Inawashiro contain proteins with lesser extent than other Japanese pumpkins, but lipids and minerals with more extent than western pumpkins. Kogiku pumpkins which were stored for 36 days post harvesting contain more β-carotene and vitamin C than other Japanese pumpkins. β-Carotene in those for 111 days post harvesting increased approximately by three fold, but vitamin C decreased by one third. 111 days that have been passed since harvesting in early September is almost corresponded with the winter solstice when Japanese people are accustomed to have pumpkins. A previous study has demonstrated that sweetness of pumpkins increased around the winter solstice by elevation of carbohydrate contents of them. Taken together, we suppose that a long-term storage may enhance nutritional functions of Kogiku pumpkins by concentrating of β-carotene.



The analytical methods of nutritional ingredients pressed by Consumer Affair agency of Japan

A Simultaneous Determination Method of Carotenes by Reversed Phase High Performance Liquid Chromatography, Journal of the Tsuruma Health Science Society, Kanazawa University, 36 (1), 27-31, 2012

Studies on the Components of Winter Squash, Cucurbita maxima II, Bulletin of Obihiro Otani Junior College, 23, A5-A8, 1986