Er Vandkastanjer Gode For Dig? Hvordan Man Spiser Dem?

2024 Forfatter: Cecilia Ryder | [email protected]. Sidst ændret: 2023-12-17 14:20

Vidste du, at nogle grøntsager også vokser under vand ?

Vandkastanjer er et godt eksempel. Hvis du går efter deres navn, tror du måske, de tilhører familien af kastanjer. Forkert! Kastanjer vokser på træer, mens vandkastanjer vokser under vandet.

De ligner mere frugter af en vandplante, der vokser i lavt vand. De bruges i indiske, kinesiske og flere europæiske retter. Forskning viser, at de er lagerhuse med mineraler og antioxidanter. Men hvordan hjælper de din krop? Hvordan kan du forbruge dem? Er de sikre? Hvordan smager de?

Bliv ved med at rulle for at finde svarene!

Indholdsfortegnelse

• Hvad er vandkastanjer? Hvad er deres sorter?
• Hvorfor er vandkastanjer populære?
• Hvad er fordelene ved vandkastanjer?
• Ernæringsprofil af vandkastanjer
• Sådan bruges / forbruges vandkastanjer
• Sådan køber du vandkastanjer
• Sådan opbevares vandkastanjer
• Hvordan kan du vide, om vandkastanjer er gået dårligt?

Hvad er vandkastanjer? Hvad er deres sorter?

Vandkastanjer er ikke nødder. De er akvatiske / undersøiske grøntsager (eller knolde), der vokser i Kina, Indien og dele af Europa. To arter dyrkes under navnet vandkastanjer - Trapa natans (aka vandkaltrop eller jesuitnød) og Eleocharis dulcis (1), (2).

Trapa natans (vand partisansøm eller 'Ling') dyrkes i det sydlige Europa og Asien. Eleocharis dulcis dyrkes i vid udstrækning i Kina. Derfor kaldes Trapa natans den europæiske vandkastanje, mens sidstnævnte er kendt som den kinesiske vandkastanje (1), (2)

Den europæiske kastanje har tre til fire spidse, vinklede, vinkelrette, store frugter. Den spiselige del er den møtriklignende indre kerne. Den kinesiske vandkastanje ser derimod mere ud som en roberformet knold - rund og blødere.

Begge disse arter er invasive og aggressive ukrudt. De vokser hurtigt og danner tætte måtter på damme, søer og overflader med lavt dybt vand (2).

Lokalbefolkningen nyder dog at spise disse vandgrøntsager. Skrælede vandkastanjer ristes, koges, dampes, males og koges på forskellige måder. Du kan se, at det bliver meget brugt i asiatiske retter, især i autentisk kinesisk mad.

Har du nogensinde spekuleret på hvorfor?

Fortsæt læsning!

Hvorfor er vandkastanjer populære?

Vandkastanjer er lagerhuse med mineraler, vitaminer, stivelse, fibre og phenolforbindelser. Deres stivelse og fiberindhold gør dem til en god tilføjelse til din almindelige diæt.

Da de har en høj næringsværdi, er vandkastanje knyttet til flere sundhedsmæssige fordele. Det er en væsentlig komponent i Ayurveda. Det er kendt for dets vanddrivende, antiseptiske og fordøjelsesegenskaber.

Vandkastanjepræparater kan hjælpe med at behandle dysenteri, diarré, blødning, brud og inflammatoriske lidelser (3). Hvis du vil vide mere om de sundhedsmæssige fordele ved vandkastanjer, skal du rulle ned!

Hvad er fordelene ved vandkastanjer?

Vandkastanjer indeholder mange antioxidanter og antiinflammatoriske forbindelser. Disse forbindelser hjælper med at rette fordøjelsesproblemer, anæmi og træthed. De kan også hjælpe med at reducere feber, smerte og betændelse.

1. Lindre smerter og betændelse

Ifølge kliniske forsøg hæmmer vandkastanjekstrakter produktionen af inflammatoriske forbindelser som interleukiner og nitrogenoxid. De aktive kemikalier i denne frugt nedregulerer de gener, der er ansvarlige for at producere disse forbindelser (4).

De phenoliske antioxidanter i vandkastanjer fjerner frie radikaler i dit system og forhindrer dem i at fremkalde organskader, betændelse og smerte. Derfor har vandkastanje en kraftig smertelindrende (smertestillende) virkning på din krop (4).

Med disse egenskaber kan denne akvatiske grøntsag bruges til at behandle hudirritation, mavesår, feber og aldersrelaterede hjernesygdomme (3), (4).

2. Kan hjælpe med at håndtere diabetes

Rodgrøntsager som vandkastanjer gemmer vand og næringsstoffer og leverer dem til planten. Derfor er de rige på fiber, mineraler, antioxidanter og stivelse. At gøre vandkastanjer til en del af din diæt kan hjælpe med at håndtere diabetes (5), (6).

Selvom denne grøntsag har ret store mængder stivelse, har dens fiber- og antioxidantindhold overhånden (5), (6).

3. Har antioxidant- og kræfteffekter

Potentielle antioxidanteffekter er blevet identificeret i forskellige dele af vandkastanje. Flere eksperimentelle undersøgelser viste, at frugt- og skrælekstrakter af vandkastanjer fjernede frie radikaler hos forsøgspersoner (7).

Derfor kan vandkastanje forhindre / bremse lipidperoxidering, tumorproliferation (vækst og metastase) og DNA-skader induceret af frie radikaler. Flavonoider som luteolin, fisetin og diosmetin er ansvarlige for denne egenskab (7), (8).

Ifølge laboratorieforsøg kan kinesiske og europæiske vandkastanjer udøve kræftaktivitet mod humane bryst-, lunge- og tyktarmsceller (8).

4. Kan sænke blodtrykket (hypertension)

Vandkastanjer indeholder meget mineraler. Sammenlignet med hvede, mel, vand chestnut mel har højere kalium, magnesium, zink og kobber indhold. Dette mel bevarer også sine antioxidantegenskaber i modsætning til hvedemel. At medtage det i din diæt kan hjælpe med at regulere blodtrykket (9).

Sammen med vandkastanjer forbedrer tilføjelse af mørkegrønne bladgrøntsager og cruciferous grøntsager også hjertesundheden. Sådanne fødevarer med højt kaliumindhold er kendt for at slappe af i hjertemusklerne og forhindre slagtilfælde (10).

Moreover, these vegetables are low in calories and carbohydrates. They may help people with hypertension to lose weight (10).

5. Exhibit Antimicrobial Activity

Water chestnut extracts can eliminate bacterial strains like Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes. Shigella sonnei and Bacillus cereus were also found to be susceptible in another study. Water chestnut extracts inhibited the growth of helminths (worms and insects) as well (11), (12), (13).

These studies prove the antibacterial nature of green and red water chestnuts. Since they can kill several pathogenic strains, their extracts can be used to treat bacterial infections (11), (12).

Moreover, this antibacterial activity is comparable to the effect of standard antibiotics (like kanamycin). Therefore, adding water chestnut to your food may increase its shelf life (11). This plant may also purify water bodies with this antimicrobial effect.

Such health and ecological benefits are attributed to the mineral, vitamin, and phytochemical content of water chestnuts.

Find out more about their nutritional value in the following section.

Nutritional Profile Of Water Chestnuts

The water chestnut plant contains minerals like calcium, phosphorus, iron, copper, manganese, magnesium, sodium, and potassium.

The fruit kernels contain vitamins A, B, and C, and functional proteins.

The water chestnut fruits contain carbohydrates, minerals, and fair amounts of phenolic compounds. The flavonoids, flavones, saponins, phytosterols, oils, and tannins in them contribute to their antioxidant properties. It is these polyphenols that scavenge free radicals from your system (14).

Consuming water chestnuts means supplying your body with all these phytonutritional components.

How can you do it? Can you eat raw water chestnuts or should they be processed?

Keep reading for answers!

How To Use/Consume Water Chestnuts

Freshwater chestnuts can be eaten raw after peeling and washing them well. They are crispy and taste mildly sweet, similar to lotus root.

No matter how long you cook or steam them, these corns have a magical power to remain crunchy.

Therefore, you often see them added to soups, ramen, stew/stocks, and any broth-like preparation for a fresh and crunchy twist.

Don’t you want to taste water chestnuts? Let’s stir up something quick with them!

Here’s a simple recipe you can try in your kitchen right away!

Water Chestnut And Veggies Stir Fry

What You Need

• Olive oil: 1-2 tablespoons (enough for a stir fry)
• Water chestnuts: 1 ounce (canned or fresh), sliced
• Broccoli florets: 5-6, washed and cleaned
• Snow peas: 1 pound, fresh, trimmed
• Baby corn kernels: 6-8, fresh, sliced into halves
• Bell peppers: 1-2 medium-sized, sliced long
• Fresh mint: 1 tablespoon, chopped
• Sesame seeds: 2 tablespoons
• Salt: to taste
• Pepper: to taste
• Skillet: 1, medium-large

Let’s Make It

1. Place a large skillet over a medium-high flame and add olive oil.
2. Once the oil is hot, stir in the broccoli, snow peas, baby corn, and bell peppers. Cook for 2-3 minutes.
3. Toss in the water chestnuts, mint, and sesame seeds.
4. Cook and stir well for about 3-5 minutes more, until the vegetables are tender.
5. Sprinkle salt and pepper and give a final stir.
6. Serve hot alongside rice, noodles, or flatbreads.

Such sides or stir-fries are a super healthy and tasty way of incorporating these nutty water vegetables into your diet.

This dish can give your body a boost of antioxidants and much-needed micronutrients.

You can find a horde of such quick, simple, and nutritious recipes with water chestnuts. They go very well with greens, chicken, and meat dishes.

You can dry water chestnuts and get them milled for flour. Water chestnut flour can be used in baking and cooking, similar to wheat flour.

But before you think about cooking with it, let’s talk about how to pick the best water chestnuts at the grocery store.

How To Buy Water Chestnuts

You can find fresh water chestnuts if you live close to a pond or a lake that has been invaded by this plant. If not, you can get them from supermarkets that sell international foods or Asian grocery stores.

Pick the hard and glossy ones. Ensure that they have no pits, bruises, or mushy spots. Good quality and healthy water chestnuts should look bright and white on the inside. They should taste sweet and nutty.

How To Store Water Chestnuts

After buying water chestnuts, store them unpeeled in paper bags in the refrigerator for up to a week. You can also freeze them in suitable containers. They last up to 5-6 months at 0ºF.

It is better to peel water chestnuts just before use. Storing peeled ones in water may rob them of their fresh taste and texture.

If you still wish to do so, keep them in this condition only for 2-3 days. Change the water every day.

Some of us find it convenient to cook and store such vegetables. The best way to do so is to boil water chestnuts, peel them, pack them in freezer bags/suitable containers, and freeze.

Label the bags with the date of packing. Leave enough headspace in each bag to prevent rotting or partial freezing.

Cooked, peeled, and frozen water chestnuts will last up to a year if stored the right way.

Another fuss-free option is using canned water chestnuts. Good quality water chestnuts are washed, peeled, and stored in brine (saltwater) before canning. You can buy them here.

You can use canned water chestnuts just like the fresh ones. They taste similar. Once opened, the leftovers need to be stored in fresh, filtered water. Change the water every day.

How Can You Tell If Water Chestnuts Have Gone Bad?

Water chestnuts spoil quickly if not stored well. Do not use the canned contents if they smell off and feel slimy.

Fungal molds may develop in the containers if you don’t change the water. This can also happen in the cans.

Be careful when you are buying water chestnuts – fresh or canned ones.

Sometimes, the fresh ones may be picked from a lake/pond that has polluted/contaminated water. Therefore, stick to a trusted source/brand.

Also, check the expiration date and storage conditions before purchasing canned water chestnuts.

In Summary

Water chestnuts are aquatic corns that grow in shallow water bodies. The plant and its fruits are rich in minerals, vitamins, antioxidants, and starches. This is why they have been traditionally used to treat dysentery, diabetes, and blood pressure.

Their antioxidant activity is also thought to reduce the risk of cancer. However, there is not enough information about its safety and side effects.

Hence, talk to your dietitian or healthcare provider about water chestnuts. If permitted, try cooking and baking with it. Follow our storage tips to recreate that favorite Chinese dish of yours any time of the year! Share your feedback in the section below.

14 sources

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