Horned Cucumber: Intolerance & Allergy

The horned cucumber belongs to the annual cucurbit family and originated in southern Africa, but is now cultivated almost worldwide in semi-arid, warm regions. The annual plant produces spiny, ellipsoid, golden-yellow fruits about 10 to 15 centimeters long. The taste of the greenish pulp is somewhat reminiscent of bananas, lemons and passion fruit.

This is what you should know about the horned cucumber.

The taste of the greenish flesh of the horned cucumber is somewhat reminiscent of bananas, lemons and passion fruit. The horned cucumber (Cucumis metuliferus) is known in Europe under the trade name Kiwano. The climbing plant with a length of up to 5 meters, which belongs to the gourd family (Cucurbitaceae), is annual and monoecious. This means that each plant bears male and female flowers. Stems and leaves are densely armed with spines, and the skin of the ellipsoid, golden-yellow fruits, which can be up to 15 cm long and weigh up to 700 grams, is covered with spiny thickenings. The green flesh, reminiscent of the inside of a cucumber, has an exotic flavor that is difficult to describe and is somewhat reminiscent of banana, lemon and passion fruit. North of the equator, harvest time begins in August. Ripe fruits that are suitable for direct consumption can be recognized by their orange-yellow skin. Fruits that are not yet ripe, which can be identified by their still green skin, can ripen at room temperature without any problems. In the trade the fruits are offered approximately from January to June. The country of origin of the horned cucumber is Namibia. There it has probably been known for more than 3,000 years. Surprisingly, the fruit has only been on the market since the 1980s. The horned cucumber probably also reached New Zealand by chance, where it has been cultivated since the 1920s and gradually became known and popular. The fruit is now grown in many semi-arid areas – including north of the equator. The main exporting countries for Europe and USA are Israel and New Zealand. In Queensland, Australia, the plant has been reintroduced and is considered invasive there. The horned cucumber can also be grown in the home garden. The best location here is on a south-facing wall with a warm microclimate. Instead of sowing outdoors, however, it is recommended to grow it indoors. The plantlets can then be planted out in the garden around mid-May, where they will soon need a climbing support from a height of about 40 cm.

Importance for health

The ripening times of horned cucumbers or kiwanos cultivated south or north of the equator differ by 6 months in each case. This leads to the fact that the fruit, in conjunction with its good shelf life for several months, is offered fresh by retailers throughout the year. This means that the fruit with its exotic, but not particularly intense, taste can refresh the winter menu in the sense of the word. Similar to cucumbers and melons, the water content of horned cucumbers is very high with a low carbohydrate content and correspondingly low calorie content. With 22 kcal per 100 g of flesh of the kiwano, the fruit is also well suited for calorie-conscious people. However, the value of the kiwano consists not only of ingredients that it does not have, but also of ingredients that it does have. These are mainly minerals such as potassium, magnesium, calcium and iron as well as valuable vitamins from the B-complex. The high potassium content is particularly worth mentioning because it has a mild diuretic effect and contributes to drainage. The flesh of horned cucumbers contains almost no fiber and dietary fiber, so it is very light and easily digestible. The thick skin, covered with horn-like projections, is not suitable for consumption. However, it can be very decorative to spoon from it, for example, prepared appetizers or desserts in combination with the flesh of the kiwano directly from the shell.

Ingredients and nutritional values

Nutritional information

Amount per 100 gram

Calories 44

Fat content 1.3 g

Cholesterol 0 mg

Sodium 2 mg

Potassium 123 mg

Carbohydrates 8 g

Dietary fiber 48.2 g

Magnesium 40 mg

The ingredients of the horned cucumber are in some areas – similar to the related cucumbers – rather a little inconspicuous.The most striking feature is the low content of primary ingredients. The protein content is 1.78 g per 100 g of pulp and the fat content is 1.3 g. The value for carbohydrates is about 8 g per 100g. The low content of primary ingredients explains the low energy content of 44 kcal per 100 g of pulp. In the field of secondary plant compounds, the picture is different. Horned cucumbers score particularly well with their content of minerals and some B vitamins. The high potassium content of 124 mg per 100 g of flesh is particularly striking. Other minerals such as magnesium (40 mg), iron (1.13 mg) and others also reach health-promoting concentrations. The content of vitamins from the B-complex also reaches health-promoting concentrations. Particularly noteworthy is niacin (vitamin B3), which is present in a concentration of 0.565 mg per 100 g. Other important substances are folic acid, pantothenic acid, beta-carotene, vitamin A and thiamine.

Intolerances and allergies

Direct intolerances or allergies to the consumption of horned cucumbers are hardly known. In general, it should be noted that known allergies or intolerances that exist to other fruits or vegetables of the cucurbit family (Cucurbitaceae) are very likely to occur after eating flesh of horned cucumber. The most common symptoms in rare cases of intolerance or allergy to kiwano fruit pulp are facial flushing, facial swelling, or asthma attacks after eating the fruit. Also, milder symptoms such as sneezing attacks and mild skin lesions. In extremely rare cases, dangerous anaphylactic shock can occur.

Shopping and kitchen tips

August through December is the most convenient time to purchase fresh horned cucumbers harvested in southern Europe or Israel. Kiwanos grown in the southern hemisphere are usually available from January to June. A ripe fruit can be identified by its golden yellow skin, although the flesh retains its green color even when ripe. The thick skin should be unbroken and have no dents. If the skin of the offered fruit is still entirely or partially green and no immediate consumption is planned, the horned cucumbers can ripen well at room temperature. In no case should the fruits be stored in the refrigerator, because then they very quickly lose their flavors and take on a mushy consistency. At a temperature of 9 to 11 degrees, the kiwano remains fresh for several months and can be stored well.

Preparation tips

A very simple and popular way to prepare kiwano is to cut it in half lengthwise with a knife and simply scoop out the flesh. The abundant whitish seeds can be eaten along with it. Alternatively, the pulp can be strained through a sieve to separate the seeds. The half-shells can later be used, for example, as decorative vessels for starters or desserts. The pureed pulp is also used as a basis for preparing refreshing drinks with the addition of sugar and lime juice. As an ingredient for salads and for decorating cold platters, the horned cucumber is equally suitable.