Unternehmensnachrichten über Comparing Dry-Type and Wet-Type Fish Feed Extruders: Key Differences

The most obvious difference lies in physical properties, primarily reflected in three indicators: hardness, expansion rate, and water resistance. Regarding hardness, feed produced by dry extruders, due to its lower moisture content and denser structure, generally has a hardness 50%-80% higher than that produced by wet extruders. For example, pet chew sticks can reach a hardness of 50-60N, suitable for dogs to chew and clean their teeth. Feed produced by wet extruders has a moderate hardness (20-30N), suitable for young pets and fish. In terms of expansion rate, wet extruders, through the synergistic effect of moisture and heat, can achieve an expansion rate of 30%-50%, forming a uniform honeycomb structure inside the feed, resulting in higher buoyancy and digestibility. Dry extruders have an expansion rate of only 10%-20%, with a relatively dense structure, suitable for sinking feeds. Regarding water resistance, fish feed produced by wet extruders generally withstands water for 30-60 minutes, while similar feed produced by dry extruders only withstands water for 10-15 minutes, easily disintegrating in water and leading to nutrient loss.

There are also significant differences in nutrient retention and digestibility indicators. Dry extruders are prone to localized overheating (reaching over 150℃), resulting in significant loss of heat-sensitive components, such as vitamin E, with a retention rate of only 60%-70%. Wet extruders offer more stable temperature control (100-130℃), and the moisture buffers the heat's impact on nutrients, allowing for a vitamin E retention rate of over 85%. In terms of digestibility, feed produced by wet extruders has a higher starch gelatinization rate (90%-95%) than that produced by dry extruders (75%-80%), increasing protein digestibility for fish by 15%-20%. A sea bass farming trial showed that sea bass fed wet extruder feed gained 18% more per day than those fed dry extruder feed.

The finished product appearance and palatability also differ: feed produced by dry extruders has a rougher surface and a darker color (due to a more complete Maillard reaction), making it suitable for the flavor preferences of pet treats; feed produced by wet extruders has a smooth surface and uniform color, better suited to the feeding preferences of fish and young pets.

Customer visit

Certificate of Honor