Friday, May 18, 2012

Ripe Gac Fruit

Gac Fruit Plant


Interior of Gac Fruit

Gac Fruit Plants

My wife Kim used to eat this unusual gourd as a child in Vietnam. Discussing Gac fruit brings back fond memories for her. We have travelled through Vietnam on ocassion and there are still a few fruit in the world that have captured my curiosity.

The Gac fruit is one of these curiosities. It is not always convenient to stop at a road side fruit stand and sample the local fruit. Unfortunately sometimes I have to wait years before I get to quench my curiosity. I will be back in Saigon later this year around Vietnamese New Years and will get the chance to eat my fill of Gac!

What is Gâc?

You are probably aware that tomatoes are high in lycopene.  But are you aware of a fruit that has 70X higher lycopene than tomatoes? And, you are probably aware that carrots are high in beta-carotene.  But are you aware of a fruit that has 10X higher beta-carotene than carrots?

It is estimated that there are between 250,000 to 300,000 species of flowering plants, and regrettably, only about 10% of them have been investigated for commercial or medicinal potential. Gâc (Momordica Cochinchinensis Spreng)(pronounced "Geuk" by native Vietnam speakers) is relatively unknown in western agricultural circles. Guichard and Bui first identified carotenoids in Gâc fruit when they traveled to Vietnam in 1941. The discovery of Guichard and Bui rocked the scientific world.

According to a 2004 USDA paper (reference below), Gâc aril (the red seed sac) has about 40-70 times the lycopene of tomatoes, and 10 times the beta carotene of carrots. West and Poovlet reported a concentration of 18,810 ug of betacarotene, and 89,150 ug total cartenoids per 100g.  This is the real deal. Today, cultivation of Gâc is exceedingly rare outside its native habitat of SE Asia. This is highly unfortunate and represents a missed opportunity for the health conscious consumers worldwide.

Gâc is a bright-red fruit that grows as large as a cantaloupe and covered with short spines, hence it is sometimes referred to in English language as "Spiny Cucumber" or "Balsampear".  It grows abundantly on attractive, vigorous tropical vines all over sub-tropical Asia, especially in Vietnam.  The vine is mildly drought tolerant, and reportedly hardy to 10 degrees F.  The large seeds cannot be spread by birds and the plant is considered non-invasive.  A fountain of antioxidants, as recent scientific research unveiled, this fruit is grown in home gardens and valued for its medicinal potentials.

Unfortunately, cultivation of Gâc is exceedingly rare outside its native habitat of SE Asia.  In Asian households, the red oily pulp is often cooked with rice. The color and fatty acids from the fruit pulp and seed membrane are stirred into the rice, giving it a lustrous appearance and oil-rich, mild nutty taste. The bright red color generates the visual effect that represents good luck and joy in Vietnamese tradition.

What are the health benefits of Gâc?

Recent scientific analysis of Gâc oil has revealed that gâc contains significant and extraordinarily high amounts of important anti-oxidants necessary for good health and slowing the effects of aging. The impressive graph below compares the amount of lycopene in Gâc fruit to other common fruits which are already known for their high lycopene content.  Gâc fruit contains 20X-70X higher lycopene than tomatoes. As such, Gâc is a commercially viable source of this important phyto-nutrient.  The lycopene is contained in the aril, which is the red oily sacs surrounding the seeds.  Insignificant amounts of lycopene are found in the orange mesocarp flesh of the fruit.

Gâc fruit oil also contains beta-carotene in significant and extraordinarily high amounts, approximately 10X higher than vegetables already known for their high beta-carotene content, such as carrots. Gâc also has high levels of fatty acids which creates a lipocarotene to deliver higher bioavailable carotenoids. Compared to beta-carotene found in carrots and dark-green vegetables, beta carotene from Gâc fruit appears to be more easily absorbed. Gâc extract has been shown effective in colon cancer tumor remediation in mice (reference below).

Carotenoids in plants are the primary dietary source of vitamin A worldwide. The most efficient pro-vitamin A carotenoid is beta-carotene which is abundant in yellow and orange fruits, such as mangoes, papayas, yams, and of course  Gâc, and in green leafy vegetables such as spinach, kale, sweet potato leaves, and sweet gourd leaves.   In developing countries, thousands of children go blind every  year due to a dietary deficiency of vitamin A.

Consumption of foods rich in b-carotene theoretically can replete individuals to a healthy vitamin A status.  Gâc is remarkably high in beta-carotene and is an outstanding potential resource as a natural cure for Vitamin A deficiency.

A number of studies have shown that each of the each of the carotenoids (such as alpha-carotene, lycopene, lutein, canthaxanthin, zeaxanthin, and cryptoxanthin) can have different functions as well as concentrate differently in various tissues. For example, lutein levels are highest in the retina, the liver, and the lungs. Alpha-carotene levels are highest in the breast and cervix, while lycopene is very high in the liver, lungs, and breast.

Carotenoids play a major role in cancer prevention and control, and each acts in a specific organ or tissue. Some of the carotenoids, including alpha-carotene, beta-carotene, beta-cryptoxanthin and gamma-carotene, are converted in the body into vitamin A. Others can be metabolized into a great number of compounds that have also been shown to inhibit cancer. And because they can be dissolved in lipids as well as water, they play a major role in protecting the brain.

Many people are aware that very high doses of vitamin A over extended periods can cause liver and brain toxicity, especially in the very young. The unique thing about carotenoids converted to vitamin A is that they will never produce enough vitamin A to be toxic, no matter how high a dose of the carotenoids taken. There is no known toxic dose of beta-carotene, even for infants.

It could be said that the Vietnamese people have the lightest, smoothest, and healthiest skin of all Asian races.  Recent scientific studies have demonstrated the skin rejuvenating, toning, and youth enhancing benefits of Gâc oil, and recent products have been introduced to capitalize on this.

What does Gâc taste like?

Gâc flesh and oily sacs are quite palatable and have very little taste,  it could be described as a very mild taste, in the same way that a cucumber has very little taste.  It is only slightly sweet or not sweet, and it would definitely not be described as delicious, more like plain or bland slightly nutty taste.  The aril texture is soft and mushy, similar to raw chicken livers.  The mesocarp (light orange outer fleshy part under the spiny skin) is about 2 cm thick and has a soft spongy texture.  It is normally discarded (composted!).  When the seeds and oil sac are cooked with rice, they impart a lustrous appearance and oil-rich, mild nutty flavor to the rice.

As with any pure vegetable oil, pure Gâc oil is not delicious, and it would not be wise to try to get your family to take it with a teaspoon in pure form.  Soft gels is the preferred method to take pure Gâc oil.  This is similar to many other vegetable oils, which by themselves are quite unpleasant to ingest. Olives are delicious, but a spoonful of olive oil, well, you get the picture.

For western diets, a convenient way to prepare Gâc is to drop the seed sacs into a pot of tomato sauce and cook briefly.  Of course if your tomato sauce has a rich tomato taste and already contains some other healthy ingredients like olive oil and garlic, the Gâc imparts almost no detectable flavor to the tomato sauce while turbo-charging it with phyto-nutrients. Add it to your spaghetti sauce, use it to make some pizza or lasagna, or slip it into your favorite salsa recipe! If you have had the opportunity to try fresh Gac please leave your comments below for other visitors to check out...

*Excerpts of this article are credited to:

1 comment:

  1. I bought gac seeds from three or four sellers, and finally got some to grow. I now have six vines, but only one female among them. I have about twenty fruits on that vine, some seemingly appearing to be almost ripe. In a month or two there should be ripe fruit which I will be seeing and tasting for the very first time. I live in central Florida, and I believe I am the only person around with these wonderful vines. I will be willing to sell fresh seeds when I start harvesting.


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