Flowers in the kitchen

Although flowers can be part of our diet, there are the plants parts less considered in gastronomy. Apart from providing color and beauty to our meals, flowers can enrich our diet with different nutrients and textures. In this post, we talk about what kind of flowers are used in different cultures kitchens and what benefits they can bring.

ROOT, STEM OR LEAVE EATING?

Maybe you have never asked yourself about what part of the plant you are eating when you consume a potato, a lettuce, a tomato or a sunflower seed but all cited vegetables are different plant organs with distinct properties and functions. Potatoes, carrots, sweet potatoes, beets and mandioques are roots or tubers and contribute our organism with many nutrients. One of the functions of the roots is to accumulate reserves for the leaves and flowers development, so these organs constitute a valuable source of high-energy carbohydrates and vitamins. On the other hand, the greenest and crispiest vegetables in our diet like lettuce, spinach and chard are leaves and its function is to do the photosynthesis. His contribution to our diet is very beneficial because they contain lots of fiber, vitamins and minerals. Following our plant tour we can continue with fruits, sometimes called vegetables such as tomatoes, zucchini, peppers, eggplants and beans. The fruits include highly rich nutrients because have their function is to accumulate nutrients for seed germination. They contain fiber, sugars, minerals and a large intake of vitamins. Finally, many also consume seeds and nuts, such as almonds, walnuts, pine nuts and peanuts. These feed us with beneficial fats and essential amino acids, fiber and vitamins.

There are other plants parts less frequently consumed, but all plant organs can have a profit! The stem or trunk is usually too fibrous and hard to eat although some species are made of trunk such as cinnamon (Cinnamomum verum).

And flowers? What role do they have in our diet? The showy and most ephemeral plants part have been used throughout history and cultures to feed us or their uses are limited to ornamentation?

EATING FLOWERS

In fact, we regularly consume flowers although perhaps we do not perceive. In the Mediterranean diet, one of the most popular vegetable is a flower: the artichoke (Cynara scolymus) is an inflorescence from which we only consume the basis of the floral bracts and the receptacle when it is not yet mature. Also capers (Capparis spinosa) are buds used in vinegar in the preparation of many Mediterranean dishes. When you eat broccoli or cauliflower (Brassica oleracea) you are also eating the immature flowers of these plants.

Capers buds to consume and an open caper flower. Source: PresidenciaRD by Flickr.

Another common flower in the Mediterranean, with a very special taste is Aphyllanthes monspeliensis. Its flowers are very sweet and is a delight to eat them while you walk through the countryside. Also elder flowers (Sambucus nigra) are used to prepare delicious and very aromatic bunyols at Spain. The elder flowers are anti-inflammatory, antiseptic and diuretic and they act against colds, fever and bronchitis.

In other cultures, the flowers are used for flavoring desserts and sweets. For example at Turkey and Iran, rose water (Rosa sp.) is used to make the famous lokum or Turkish delight.

Turkish delights aromatized with rose water. Source: Pinterest.

Other flowers used in infusion are hibiscus flowers (Hibiscus sabdariffa). Only sepals are used to prepare an iced tea with diuretic properties, very popular in Jamaica but also common in Mexico and other countries in Central America.

Hibiscus dried sepals. Source: Commons Wikimedia.

The violet flower (Viola odorata) is also very sweet and aromatic. It is used to make a famous candy from Madrid, manufactured from 1915, with calming properties. Viola flowers can also be sued to make pies, jellies and ice cream.

Violet candies typical from Madrid. Source: morenisa.blogspot.com.

The zucchini flowers (Cucurbita pepo) after the stamens have been removed, are used in Italy for a very original pizzas. Similarly, in Greece and Turkey, they eat pumpkin flowers (Cucurbita maxima) batted or stuffed and fried. They are also used in Mexico to make quesadillas.

Zucchini flowers pizza. Source: Gourmand Asia.

Flowers have been used at kitchen from Roman and Greeks time. They used flowers in salads, like mallow (Malva sylvestris), that has soothing and healing properties in infusion.

Flowers add color, texture and beauty to our meals while they can also provide taste contrasts, as they are not always sweet and soft. For example, cornflower (Centaurea cyanus) and nasturtium (Tropaeolum majus), both edible flowers have a spicy taste and borage (Borago officinalis) reminds cucumber and can be used in salads, soups or drinks. The chives flowers (Allium schoenoprasum) are often used to add a very special taste of garlic at salads and soups.

Nasturtium flower. Source: David Goehring by Flickr.

Borage flower. Source: Commons Wikimedia.

Some spices come from flowers or organs flower. Saffron (Crocus sativa) is the female organ (style and stigma) of this species bloom, giving color and flavor to spanish paellas. Its cultivation is extremely delicate and expensive: 200 thousand of flowers or 600 thousand of pistils are needed to produce 1 kg of saffron. Spain is the world’s largest producer. Cloves (Syzygium aromaticum), originally from Indonesia, are in fact dried buds of a tree that can reach 12 m high. Its strong smell can help in producing a natural insecticide prepared with cloves infusioned with distilled water and alcohol.

Saffron flowers with its typical red pistils. Source: pixabay.

Maybe not all the flowers mentioned are affordable but we encourage you to include flowers in your meals while learning more about plants cooking them.

REFERENCES

Graziano, X. 2010. Almanaqueo do Campo. Panda Books, Sao Paulo, Brasil.

Carnivorous plants

The carnivorism is a nutrition style associated to animals, to the world of heterotrophs. But it has been seen that there are plants that are also able to feed on other organisms. They are called carnivorous plants and their strategies to capture dams are very different and curious.

WHAT IS A CARNIVOROUS PLANT?

A carnivorous plants , even being autotroph, get part of their nutritional supplement by feeding on animals, especially insects.

There are three basic requirements that  carnivorous plants must comply:

• they must be able to attract, capture and kill the preys. To get their attention, they usually show reddish coloration and secrete nectar. Morphological and anatomical adaptations for retaining and killing the preys such as traps are used.
• Digestion and absorbance of the nutrients releasedby the damn .
• And finally, it has to draw significant benefit from the process.

Venus flytrap (Dionaea muscipula) (Author: Jason).

WHERE DO THEY LIVE?

Carnivorous plants are  not competitive in normal environments and tend to have a small root system, they need this specialization to allow them to grow faster. They are usually found in low mineralization soils, but with a high concentration of organic matter, sunny areas (as they still perform photosynthesis) and with  a high humidity.

Normally they are also calcifuges, i.e., they are not well adapted to alkaline soils and prefer acidic environments, where the source of calcium comes from the prey. They tend to inhabit soils with low oxygen and  saturated in water in a reducing environment. Some are aquatic and live either floating or submerged, but always near the surface.

TRAPS AND EXAMPLES

The capture system is quite diverse, but can be classified according to whether there is movement or not. We consider active strategies for those plants having mechanical or suction movements. Semi-active strategies which present mucilaginous glands and have movement and finally, passive ones, with no motion for prey capture. They can present mucilaginous glands or pitfall traps. Somes amples are given below.

ACTIVE TRAPS

Venus flytrap

In the case of this plant, the traps are mechanical and they are formed by two valves joined by a central axis. These valves are the result of non photosynthetic leave transformations. The stem acts as a petiole and performs photosynthesis, for this reason, it is thickened, increasing its surface and facilitating the process. Furthermore, the valves have nectar glands to attract preys and its perimeter is surrounded by teeth which help the capture, as when the trap is closed, the teeth overlay perfectly avoiding the animal’s escape..

But, what mechanism drives the closing? There’s a gigh number of triggers hairs inside the valves. When the dam is located on the trap and makes the trigger hairs move twice or more in less than 20 seconds, the valves close immediately.

In this vídeos From the BBC one (Youtube Channel: BBC) we can observe the whole process.

Utricularia, the bladderwort

This plant lives submerged near the surface and is known as the bladderwort, because it has bladder-like traps. The bladders are characterized for having sensitive hairs that activate the suction mechanism of the dam. Then, the bladder generates a very strong internal pressure that sucks water in, dragging the animal to the trap. It’s volume can increase up to 40% when water enters.

In the following video we can see the bladderwort trapping a tadpole of cane toad (Youtube Channel: Philip Stoddard):

SEMIACTIVE TRAPS

When I caught you, you won’t be able to escape

The presence of stalked mucilaginous glands is not unique in the carnivorous plant world, many plants use them as a defence or to prevent water loss. But, some carnivorous plants they are used to capture animals, as the sundews (Drosera) does.

The glands presents on the leaves of the sundews are formed by a stalk and an apical cell that releases mucilage. This substance attracts preys by its smell and taste. When the dam is located on the leaves, some drops of mucilage join each other to form a viscous mass that will cover all the prey, preventing its escape. We note that the glands have some mobility and move themselves to get in contact with the prey. Also, as a result, the leaf wrappes, facilitating the subsequent digestion.

The following video shows the operation of this mechanism (Youtube Channel: TheShopofHorrors):

PASSIVE TRAPS

Don’t get to sticky! 

The Drosophyllum‘s case is very similar to the previous one, but this time the stalked mucilaginous glands don’t have mobility and, therefore, the leaf doesn’t have either. The insect gets caught just because it is hooked on it’s sticky trap and cannot escape.

Insects trapped by Drosophyllum‘s stalked mucilaginous glands  (Author: incidencematrix).

Carefull not to fall!

Finally, we see the passive pitfall traps. They sometimes have a lid that protects them from an excess wàter getting in, even though it isn’t a part of the trap mechanism. The pitfall traps can be formed by the leaf itself or by an additional structure that is originated from an extension of the midrib (the tendril). The tendril lowers to ground level and then forms the trap.

Nepenthes (Author: Nico Nelson).

Dams are attracted to these traps due to nectar glands located inside. Once inside, going out is very complicated!  Walls may be viscous,  have downwardly inclined hairs that hinder to escape or present translucent spots that suggest the prey that there’s an exit, acting like windows , confusing and exhausting the prey, making it fall to the bottom, where it will drown. Other species also release substances that stun the preys, preventing them from running away.

Heliamphora (Author: Brian Gratwicke).

In some cases, large animals have fallen into these traps, though it is considered more as an effect of “bad-luck” than the plants supposed diet, though some traps measure up to 20cm long.

REFERENCES

• Notes of Environmental Plant Physiology, Degree of Environmental Biology, UAB.
• International Carnivorous Plant Society – http://www.carnivorousplants.org