Storage and shelf life management of concentrated aquatic feed: key points to avoid nutrient loss

Concentrated aquatic feed, due to its high protein content and numerous added ingredients, is prone to problems such as nutrient loss and mold growth if stored improperly, which directly affects the effectiveness of aquaculture. To effectively manage storage and shelf life, the core is to control "environmental variables" and "operational details". Below are specific methods broken down from four key dimensions.

1、 Choosing the right storage environment: controlling three core conditions

The environment is the primary factor affecting the nutritional stability of concentrated feed, and temperature, humidity, and light should be strictly controlled to avoid the decomposition of nutrients (such as proteins and vitamins) or their destruction by microorganisms.

1. Temperature: not exceeding 25 ℃, keep away from heat sources

Vitamins (such as vitamin A and E) in concentrated feed are sensitive to high temperatures, and excessive temperature can accelerate their oxidative failure; Proteins may also undergo denaturation at high temperatures, leading to a decrease in digestion and absorption rates.

Choose a cool and ventilated storage location (such as a shaded area in a warehouse or basement), and avoid being close to boilers, heating systems, or window sills with direct sunlight;

During high temperatures in summer, cooling fans can be placed in the warehouse or windows can be covered with sunshade cloth to control the temperature between 20-25 ℃.

2. Humidity: below 65%, strictly prevent moisture

A humid environment can easily cause feed to absorb moisture and clump, as well as breed mold (such as aflatoxin), which not only damages nutrition but may also cause poisoning in aquatic animals.

The warehouse floor needs to be elevated (using wooden frames or pallets to support feed) to avoid direct contact with moisture on the ground;

Close the doors and windows of the warehouse on rainy days, and place desiccants (such as silica gel desiccants and quicklime) inside the warehouse. Regularly check if the ground is damp again, and promptly remove clumped feed if found.

3. Lighting: Store away from light and isolate from ultraviolet rays

Ultraviolet radiation can damage vitamins in feed, especially vitamin C and B vitamins, and may also accelerate fat oxidation, producing harmful substances.

Feed should be sealed in opaque packaging bags (such as woven bags with plastic lining), and any remaining feed should be promptly placed in a light shielded sealed bucket after opening;

Avoid using transparent glass windows or applying shading film to windows in the warehouse to reduce the entry of ultraviolet rays.

2、 Standardized operation: 4 details to reduce nutrient loss

Improper operation during storage can directly shorten the shelf life of feed and cause loss of nutrients. The following details should be noted:

1. After opening: seal in a timely manner to avoid contact with air

After opening, concentrated feed is prone to undergo an "oxidation reaction" when in contact with air, leading to protein spoilage and fatty acid decay.

After each use, immediately tie the opening of the packaging bag tightly (using a rope or sealing clip), or pour it into a sealed bucket with a lid;

After opening, try to use up the feed within 7-15 days (adjusted according to the amount of feed) to avoid prolonged exposure.

2. Stacking: Do not exceed the height, do not mix, prevent pressure damage and moisture

Improper stacking can cause the bottom feed to clump under pressure or cross contaminate with other materials.

The height of the feed pile should not exceed 5 layers (bagged) to avoid crushing the bottom layer of feed, which may affect feeding and nutrition;

Do not mix with pesticides, fertilizers, engine oil and other materials to prevent odor adsorption or chemical pollution;

Stay at least 30 centimeters away from walls to prevent moisture from seeping into the feed.

3. Access: "First in, first out", do not flip randomly

Blind use can easily lead to long-term accumulation of some feed, exceeding its shelf life.

Stacking in the warehouse according to the "production date" zone, new feed is placed in the back row, old feed is placed in the front row, and priority is given to using the feed in the front row;

When retrieving, do not flip the entire pile of feed randomly to avoid damaging the sealed state and causing moisture to the unused feed.

4. Cleaning: Regularly clean the warehouse to prevent residual pollution

The residual feed debris in the warehouse is prone to breeding insects and rodents, contaminating new feed.

Clean the warehouse once a month, sweeping away the feed residues on the ground and corners of the walls;

Check if there are any rat holes or insect infestations in the warehouse, and place sticky rat boards or insect repellents (away from feed to avoid contamination).

3、 Shelf life management: 2-step precise control, no waste, no expiration date

The shelf life of concentrated feed is usually 3-6 months (unopened, suitable environment), and it needs to be managed through "labeling+inspection" to avoid using expired feed.

1. Clear labeling: Record key information at a glance

When new feed is put into storage, label the packaging bag or stack with "production date, shelf life, and storage time";

After opening the feed, label the sealed bucket with the "opening date and estimated time of use" to remind timely use.

2. Regular inspection: Check for signs of deterioration in advance

Expired or spoiled feed will show obvious characteristics and should be checked once a week:

Check the appearance for clumping, discoloration (such as yellowing or blackening), and the appearance of mold spots;

Smell: whether there is a sour or moldy smell (normal concentrated feed has a slight aroma of soybean meal or fish meal);

Texture: Grasp the feed with your hands and feel if it is damp or sticky (normally it should be in a dry and loose state).

If the above problems are found, even if the shelf life has not expired, it should be stopped immediately to avoid causing diseases in aquatic animals.

4、 Special case handling: responding to unexpected problems and reducing losses

1. Short term moisture exposure (no clumping, no odor)

The feed can be spread out in a cool and ventilated place, flipped 2-3 times a day, dried and used up as soon as possible (within 3 days), and cannot be stored for a long time.

2. Localized mold growth (small amount of mold spots)

Immediately pick out the moldy parts, thoroughly inspect the remaining feed, confirm that there are no problems, and use it with a mold remover (such as montmorillonite) within one week.

3. Expired without deterioration (just 1-2 days after expiration, with normal appearance)

It can only be used for adult aquatic animals (such as adult fish and shrimp), and the feeding amount needs to be reduced (70% of the normal amount). Observe the animal's feeding and health status, and stop immediately if any abnormalities occur.

5、 Summary: The Core Logic of Storage Management

The key to the storage and shelf life management of concentrated aquatic feed is "oxidation prevention, moisture prevention, pollution prevention, and time control" - reducing nutrient loss by controlling temperature, humidity, and light; By standardizing operations and conducting regular inspections, we can avoid spoilage and waste. As long as we do a good job in "environmental control+detailed operation+shelf life monitoring", we can keep concentrated feed in a high-quality state, achieve the best breeding effect, and avoid losses caused by feed problems.