In commercial shrimp farming, size is only part of the product’s value. The color of the shrimp shell and flesh is the factor that has the greatest impact on the selling price at harvest. Shrimp with bright color, translucent bodies, and glossy shells are usually preferred by traders, while dull-colored, deep red, or cloudy-bodied shrimp are often priced lower, even if they meet the standard weight.
Shrimp with beautiful coloration are usually healthy, feed well, molt evenly, and grow in a stable environment. Conversely, poor coloration is a sign that the shrimp stock is under stress or that the pond environment is out of balance.
WHAT DOES SHRIMP COLOR REFLECT?
Shrimp color is the combined result of many factors, the most important of which are the ability to absorb pigments from feed and the way the shrimp’s body distributes pigments in its tissues.
In the living state, pigments in shrimp are usually bound to proteins, giving the body a bluish-gray or slightly translucent appearance. When cooked, these bonds break down, astaxanthin is released, and the characteristic orange-red color appears — the color favored by the market.
Shrimp with good coloration indicate strong feeding, nutrient absorption, and molting performance, while also reflecting a stable pond environment. In contrast, shrimp that are unusually pale or dark are often signs of stress, environmental imbalance, or poor nutrient absorption. Therefore, observing shrimp color can help quickly assess the condition of the stock and the quality of the pond.
ENVIRONMENTAL FACTORS THAT DIRECTLY AFFECT SHRIMP COLOR
Pond water color is a factor that clearly affects shrimp coloration. Ponds with a light greenish-brown or tea-brown color often create a stable environmental background, helping shrimp develop natural coloration. When the water is too clear or too dark, shrimp are more likely to become stressed, leading to pale or dark bodies.
Light and pond bottom color also affect how shrimp distribute pigments in their bodies. Research on black tiger shrimp shows that shrimp raised in dark environments or in ponds with dark bottoms tend to express pigmentation more clearly than shrimp living in bright environments. This does not change the total amount of pigment, but it affects pigment dispersion on the surface, thereby determining the color at harvest and during processing.
In addition, water quality parameters such as pH, dissolved oxygen, alkalinity, and temperature, if they fluctuate sharply, will cause shrimp stress, reduce feeding, and impair nutrient absorption. The result is poor shrimp color, dull shells, and flesh that is not firm.
The pond bottom is also an important factor but is often overlooked. A dirty pond bottom with accumulated toxic gases weakens shrimp, slows growth, and causes darker coloration. Conversely, a pond with a clean bottom and little sludge helps shrimp develop more evenly and maintain brighter color.
ADJUSTING THE ENVIRONMENT TO HELP SHRIMP DEVELOP BEAUTIFUL COLOR BEFORE HARVEST
To achieve good shrimp coloration, farmers need to actively manage the environment from the beginning of the crop. First, maintain stable water color and avoid water that is too clear or sudden fluctuations. Biological products can be used to balance the microbial community and naturally color the water.
Environmental parameters should be kept stable, including:
- pH from 7.5 to 8.5
- Dissolved oxygen above 5 mg/l
- Minimize day-night pH fluctuations
- Periodic mineral supplementation helps shrimp shells become hard and glossy and supports molting.
In terms of nutrition, the feed ration should provide adequate minerals, vitamins, and components that support pigment absorption. Combining digestive enzymes helps shrimp make better use of nutrients in the feed, thereby improving color and flesh firmness.
The pond bottom should be siphoned regularly, excess feed should be minimized, and microbial sludge treatment should be used to reduce toxic gases. A clean bottom environment helps shrimp stay healthy and develop more natural coloration.
THE PRE-HARVEST STAGE – THE DECISIVE TIME FOR SHRIMP COLOR
The 7–10 days before harvest are especially important. This is the time when farmers need to:
- Stabilize the pond environment
- Limit major water exchanges
- Provide light mineral supplementation
- Maintain the pond water color in the best possible condition
Proper technical care during this stage helps shrimp achieve beautiful, uniform coloration, contributing to higher commercial value when sold.
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Source: tepbac.com
