Physalis is a fruit widely consumed, especially fresh and in jams. It resembles a small yellow-orange cherry, which is removed at maturity from a closed calyx, membranous and green turning to brown and an aspect of paper when the fruit arrives at maturity.
Note: The fruit is edible and appreciated at maturity, but the other parts of this plant, as well as the immature fruits are toxic, as in most plants of the family of Solanaceae.
The physalis is in fact neither cherry, nor gooseberry, nor Mirabelle plum. The fruit is, in fact, much closer to the tomato, a cousin belonging to the same family (Solanaceae).
In its narrow sense, it designates the Chinese lantern, an ornamental plant of the species P. alkekengii, whose fruits are enclosed in an bright orange envelope. However, in the popular language, the word may refer to any plant of the genus physalis.
The genus physalis comprises about 100 species distributed in all tropical, subtropical and temperate regions of the world. In Central and South America, this fruit grows among many wild and cultivated species. The ground cherry (physalis pruinosa) comes from the eastern United States. The Cape gooseberry (physalis peruviana), contrary to what its name indicates, comes from the Peruvian and Chilean Andes. Minor food in most cultures, the fruit of the physalis has hardly been the subject of archaeological and palaeontological studies, so that one does not know much about the history of the plant and its evolution. It is known the Incas knew the Cape gooseberry and they consumed it most certainly.
We can find the plant in the botanical gardens of Europe in the nineteenth century and then in the private gardens. Apart from the bladder cherry (physalis alkekengi), sought for its orange bells, the plant generated a mixed interest, considered halfway between the weed and the cultivated plant. It is true it settles easily in cultures and consumes the precious minerals other plants need to grow. In addition, unlike the other edible plants of the Solanaceae family (pepper, tomato, eggplant), selectors were not interested. Thus, there are few or no cultivars with the characteristics would allow it to grow on a large scale. Although abundant, the harvest has to be done by hand, a long and tedious work requiring a large workforce. Finally, the flavor of the fruit can vary considerably from one variety to another.
The Cape gooseberry (physalis peruviana) was introduced in many parts of the world, including Africa, China, India, Australia, New Zealand and Malaysia, where it has been commercially grown for at least 200 years. Nevertheless, its potential remains clearly underexploited. In Hawaii, it was the subject of an intensive culture, and then practically disappeared from the fields. People also tried to cultivate the fruit in Israel, but consumers who have not shown much enthusiasm have replaced them with more profitable plants.
The same thing happened for the bladder cherry (physalis pruinosa) which had a mixed success, except among the amateur gardeners who, at all times, cultivated and appreciated it. However, for the last ten years, demand for local products has been growing in both North America and Europe. Jams, jellies and liqueurs are offered in specialized shops, and the small fruit is now among the best dishes in restaurants.
Physalis health profile
The ground cherry lends itself well to the making of jams, jellies and compotes. The compounds it contains would have antibacterial, anti-cancer and anti-inflammatory effects.
The benefits of physalis
Physalis consumed in North America bears the Latin name Physalis pruinosa. However, no scientific study has focused on this particular variety. Most of the research, including those presented below, has been carried out with varieties found in Europe, Asia or South America (Physalis angulata, Physalis minima and Physalis peruviana). In addition, the plant extracts used in the different studies concern the whole plant and not only the fruit.
Various benefits. The physalis is used in popular medicine to treat several infections such as asthma, hepatitis, malaria and rheumatism. Extracts from physalis leaves (traditionally used in Congo) have shown strong activity against the parasite plasmodium, responsible for malaria.
Cancer. Several in vitro studies have demonstrated the afficiency of physalis extracts to inhibit the growth of different human cancer cells (liver, lung, ovary, breast). However, clinical studies will be needed to determine whether the simple use of physalis has an effect on cancer among humans.
Inflammation. Physalis extracts produced a decrease in edema and had anti-inflammatory effects among mice and rats with arthritis and dermatitis. Compounds isolated from the root of the physalis would also have anti-inflammatory effects by decreasing among other things the production of compounds causing inflammation.
Immunity. Compounds from physalis extracts would have the ability to influence the response of the immunsystem. Researchers suggest they would have an interesting potential to replace certain immunosuppressive medications (used, for example, in the treatment of allergies or autoimmune diseases), without significant side effects.
Antimicrobial effect. Physalis extracts showed antimicrobial activity in vitro against certain bacteria, including tuberculosis. Some physalis compounds contained would play a major role in this antimicrobial effect, by binding to cell walls of the bacterium to inhibit its growth.
What’s in the cherry?
Antioxidants. Antioxidants are compounds reducing the damage caused to the organism by free radicals. They help prevent the onset of cardiovascular diseases, certain cancers and various chronic diseases. Researchers have shown the physalis could have an interesting antioxidant power. Others concluded some extracts of the physalis showed an in vitro antioxidant power equivalent or sometimes even higher than those of vitamin E (a natural antioxidant). Some flavonoids and other still unknown compounds could contribute to the antioxidant activity of the physalis.
Beta-carotene. The physalis contain beta-carotene, an antioxidant of the carotenoid family which can be converted to vitamin A in the body. Beta-carotene is the carotenoid whose conversion to vitamin A is the most effective. Vitamin A promotes bones and teeth growth, promotes good vision, keeps skin healthy and protects against infections.
Physalins. They are characteristic steroids of physalis. The anticancer effects of this fruit would be partly attributable to them. Physalins have demonstrated in vitro their efficiency in inhibiting the growth of several human cancer cells (colon, lungs, liver, larynx, and white blood cell). They are also expected to have some antibacterial and anti-inflammatory effects. Interestingly, physalins would act differently from dexamethasone (an anti-inflammatory drug) and may not have the same side effects. They would also have an effect on the activation and proliferation of immune system cells. The potential toxicity of physalins in concentrated form, however, remains to be determined, as is the efficiency of the simple consumption of the physalis.
Phytosterols. In addition to being a source of essential fatty acids and vitamin E, the oil extracted from the whole ground cherry contains phytosterols in high amount. These compounds present in plants are increasingly interesting given their antioxidant activity and their positive effects on cardiovascular health. The physalis oil could therefore present an opportunity for the development of new functional foods.
Choice and conservation
The physalis is only found in the market during the summer and fall. At other times of the year you can find this fruit in specialty shops of imported cape gooseberry, but they are very expensive.
Because the immature fruits are difficult to digest, consume only those that are with a beautiful golden yellow. Let others ripen for 1 or 2 weeks.
Some companies offer dried fruit.
Refrigerator or cool cellar. The fruit can be kept for many weeks in a cool area, in the condition its envelope is intact and it was taken care to dry it a few days in the sun after the harvest.
Freezer. Remove the fruit cover and place them on a plate you will put in the freezer for 1 hour or 2 before putting them in an airtight bag and put them back to freeze.
Dehydrator. The fruit dries easily with the dehydrator or the oven set at very low temperature.
In cold climate, the ground cherry grows better than the cape gooseberry. The culture of the latter can still be tempted knowing the results could be disappointing. Sowed in a tray inside, 4 to 6 weeks before the last expected frost. It can also be planted directly in the garden when the soil is warmed, but the harvest will be less abundant. Transplant when the risk of freezing has passed, spacing the plants from 45 cm to 60 cm in the row and 1 meter between the rows. The ground cherry tolerates a little shade, but still needs sunshine to ripen its fruit. Avoid over fattening the groung, at the risk of promoting foliage development at the expense of the fruit. The physalis can be staked, but this is not imperative, unlike the cape gooseberry, which requires good support and a regular size.
It is not necessary to force on watering, the plant preferring the soils rather dry, but it is watered in case of prolonged drought. Thanks to its envelope, the fruit has its own system of protection against insects and diseases. Without being foolproof, this system is very effective. On the other hand, the striped rootworm attacks the flowers and leaves. To limit the damage, treat the rotenone. For harvesting, you can dispose of the cloths on the ground and shake the plants to bring down the ripe fruits.
Ecology and environment
All plants of the genus physalis are an excellent ground cover and protect the bare land from erosion. Not very demanding in fertilizers and water, the plant will quickly settle on sandy or rocky soils. However, once established, it can be difficult to eradicate. It is therefore necessary to ensure that the place chosen to install it is not intended for another short term agricultural activity. In the south, it is considered a weed, especially in corn fields.