Shrimp Species and Main Proccessing Types

Sea Minh Hai specializes in processing different types of shrimp products.
 

Shrimp Species

Although Sea Minh hai can process several important commercial shrimp species available in Viet Nam such as Black Tiger shrimp (penaeus monodon), Vietnam white shrimp (Penaeus merguiensis), Pink shrimp (Metapenaeus ensis), Cat tiger... but the main species we actually process are Black Tiger and Vannamei (Litopenaeus vannamei, or also called earlier as Penaeus vannamei). The reason is scareness of other species which are basically natural caught.

Mekong Delta is rich in natural fishery resources and this is described in Trinh Hoai Duc's Gia Định Thành Thông Chí in early of 19th Century (which was translated to the French as Gia Dinh Thung Chi, or Histoire et Description de la basse Cochinchine by G. Aubaret and published in 1853 in Paris by the Imprimerie Impériale (Imperial Publisher)):

Reddish shrimp (white species) in the sea, [caught] and dried and supplied to the trading boats. Only in Vinh Thanh and Ha Tien provinces it's abundently available, each year can be harvested up to 100,000 cân*. There's a small shrimp species just about the size of the tip of the chopstick, (a small shrimp species), salted and ground to an attractive smell and tastely pink powder ([133][133]). The lobster, with stripes and spiny shell, [21a] as big as human fists, the meat serves as food while its shell serves as decorative object.

The freshwater giant prawn, with blue round shell with 4-5 tac** length with two long giant chelepeds, sweat meat that in northern provinces we cannot have. There is also a small shrimp called white shrimp, cat tiger shrimp that are also tasty food.

Trinh Hoai Duc: Gia Dinh Thanh Thong Chi, Part III, Vol 5. Translated by Ly Viet Dung. Dong Nai Publisher.

The traditional shrimp culture exists for mamy years before the modern shrimp culture is introduced. The charateristics of the Viet Nam traditional shrimp culture is that it is not manipulated and controlled by human beings to the greatest extends. These traditional ponds are called vuong (in Vietnamese vuong means large square or rectangle pond) by the farmers in the coastal provinces of the Mekong Delta, and this word is still used in some locals there today. Shrimp vuong are actually large ponds that are rectangle in shape, surrounded by a earthen dikes to keep the sea water and shrimp in. Shrimp seeds are naturally caught and put in the vuong, or with experience, farmers get the water already with natural shrimp seedlings to fill up their vuong at high tide then close the pond gates. Shrimp eat natural feeds until they grow up to marketable or usable size. One can think that time necessary for one cycle of such farming should be long, and actually it is, for farmer only catch their shrimp once per year. In the end of 19 century, a French official observed these natural fish and shrimp ponds in his report as cited below.

He used the Vietnamese trại to call the wild and desolate and far-away ponds along the Ong Doc River. Actually these are the shrimp and / or fish ponds he saw in the end of 19th century.

Modern shrimp culture has just started not long ago. One can trace it back to 1923 when Japanese scientists tried to culture Japan shrimp (Kuruma) using scientific methods. The most important waves of shrimp culture actually happened in the 1970s when both knowledge about thrimp breedings and culture have been more sophisticated, and shrimp diseases have been controlled more effectively.

Black Tiger Shrimp
This species lives naturally from Southeast Asia to the shore of East Africa (to Somali). Significant natural caught quantity however concentrates around India and Indonesia.

When the shrimp industry has been developed quickly with the improved and advanced methods, the shrimp seeds no longer depending on natural sources. It is compleletely managed in hatcheries. Thanks to these advances, the density per square meter is much higher and the yield per hectare is much bigger. In fact it is not uncommon for a production of 8 metric tons of shrimp per hectare. Thailand is the pioneer in this industry, and yield per hectar is of the highest in the world before it switches to Vannamei. Nearly all of the shrimp production is for export, and it contributes to the foreign currency earning of this country.

Vannamei shrimp
Originated in the East Pacific Ocean it is seen much in Central and South America (from Sonora State of Mexico to North of Peru). In general it lives in the seas with warm water (about 20oC) the year round.

View Vannamei in a larger map
Vannamei originates from Pacific Coast in Central America

Vannamei culture has been expanding quickly in 1970s, and today in some countries it even replaces Black Tiger species (Thailand, China, Viet Nam, ...)   In 2004, the production of the cultured of Vannamei exeeded 1,1 million metric tons. Initally vannamei has been raised by farmers in the Central and and North of South American countries only, but later it has been introduced to China, Taiwan, Indonesia, Philippine, Thailand, Vietnam, India... The advantage of the species is that it can be stocked at a very high density, short farming circle and very high yield per hectare (more than 10 metric tons per hectare can be achieved.)

Anatomy of a shrimp

Shrimp body consists of these main parts: head, body and tail.

The head consists legs, cheliped, maxilliped, antennae, rostrum and eyes. Body consists of six segments, with swimmerets in the lower part. Inside the body, there is a vein. The tail part consists of a sharp pointed part called telson and tail fans.

In processing, the meat attaching to the body after the head being removed is called hanging meat, or throat meat. The vein runs from the head part through the back of shrimp body to the tail.

Shrimp Product Terminology

There are terms particularly used in shrimp industry. Most of these terms are of English origin, but these terms are known widely in other languages too. There are also some terms originated from Japanese, too. Below are some common terms usuallly referred to when talking about shrimp products.

1. HOSO: head on shell-on. As the term explicitly expresses, this refers to the shrimp at it nearly natural form with very little human actions on them. The whole shrimp is washed, put on the trays then into the freezer, then put in the packing materials such as bags, cartons.. and finally shipped to buyers. One can notice that due to the internal parts such as stomach, hepatopancrea, guts, heart etc.. are still untouched, they can be good source of quick destructive to shrimp meat if improper temperature of storage happened. The product therefore should be very fresh or undesired quality will be resulted.

Besides the popular raw HOSO, we have also cooked HOSO. This product is limited to certain buyers for their preparation of special dishes. The picture here illustrates one such product for further processing into a dishes serving in some restaurants in the important or New year holidays.  The strong red color of the shell of the shrimp is very important in this dishes. And only some dark shell shrimp caught in extensive ponds in the Ca Mau, Bac Lieu areas can have this color, this product therefore becomes a special item supplied to some particular buyers only.

2. HLSO: headless shell-on. The heads and the veins are removed, this product is the most popular form for frozen shrimp sold in the market. In Viet Nam, it is call tôm vỏ (shell on shrimp), but this term seems not exact. The fully meaning term is HLSO for it.

We can see that there are two nearly related products to HLSO. These are the Butterfly-cut and Easy Peel. Both are process from HLSO with further cutting on the back, for Butterfly-cut, a deep cut into the meat and flat open to make up the shape of a butterly wing, and the other just a shallow cut enough to separate the shell on the back into two parts which helps the peeling off the shell more easily. This latter form is called Easy Peel.

3. PD (or PND): peeled and deveined. As indicated by the name, the gut vein is removed from the shrimp body, whether bu a shallow cut on the back to remove it (back-cut PD), or by using some pointed stick to pull the vein out (pull-vein PD). Sometimes it is referred to as meat shrimp, but the word seems not exact enought, for it can refer to both PD (this case) and PUD (see next). This is the most convenient item for food preparatoin without much labor.

4. PUD: peeled and undeveined. Similar to the about item except that the vein of the shrimp still remained. This type of processing is usually seen at small size shrimp where labor and time needed for deveining is so much, or when the vein is not significantly important in making the food. This is commonly applied in some species such as white, pind, cat tiger...

5. PTO: peeled tail-on. Most of the shell (5 segments) is removed, only the last segment and the tail fans are kept. PTO is rather common on the market, especially USA market and used in varous dishes preparation including the Westerner type of breaded shrimp (much simpler than Japanse breaded type).

6. SUSHI: Sushi is Japanese popular dish, and can be made from various materials, of which shrimp is one. Shrimp sushi (from Japanese 寿司エビ sushi ebi: shrimp sushi) is prepared from cooked-in-shell shrimp then peel, cut, and trim neatly before laying on the trays and put into bags, vacuum sealed and packed into cartons. This item is used for further processing to shrimp sushi.

7. NOBASHI: Nobashi or Nobashi Ebi (伸ばし海老) is a PTO product, but it is processed for Japanese style for Japanese buyers. The Japanese words nobashi ebi mean stretched shrimp. As the shrimp name expresses itself, the shrimp is manually stretched to reach certain length. There are some other requirements for this product: there may be some cuts made in the belly part or sides of the shrimp, the tail part (fans and telson) can be trimmed to have certain shape (for example a V -shape), tail fans can be scratched, or punched in order to drain in internal fluid. Then the way it is packed, whether the shrimp is treated with chemical (STTP) or not etc...  With these very particular characteristics, the product is considered as a separate product category, the nobashi product. Needless to say that the product is used mainly for the Japanese breaded shrimp (a three times coated with premix, battermix and breadcrumb shrimp which is very attractive look and tasty when use.)

Shrimp products can also be further grouped into two categories: the raw products and the cooked products. Combining with the above types of processing, we have raw HLSO, PTO, PD.. products or cooked HLSO, PTO, PD... products.

Finally these products can be referred to by their freezing types, whether it's block frozen, IQF, Semi IQF etc..

Please read on next part to have further information on products.

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