Types of fishmeal domestic
1. Skimmed steam fishmeal: Skimmed fishmeal production process is the raw fish after steaming, pressing, solid-liquid separation, oil-water separation, drying, cooling, screening, crushing and a series of processes. The fishmeal it produces has a protein between 62%-70%, a VBN usually ≤ 120, an acid value usually between 2-7, a pepsin digestibility of 90%-97%, and a salt content between 1-3.
2. Semi-skimmed fishmeal: Semi-skimmed fishmeal production process and the production process of skimmed fishmeal is generally the same steps, are after cooking, pressing, oil and water separation, primary drying, secondary drying, etc., the difference is that the semi-skimmed fishmeal in the oil and water separation, the separation of the water (containing salts, impurities, fats, and fine particles of fishmeal) back to the primary drying canisters, and the fishmeal mixed together The drying increases the flour yield and reduces the loss of muscle tissue due to the small size of the fish and the decay of the muscles of the unfresh fish. The color of fishmeal is due to the prolongation of drying time, the spraying back is not timely and the spraying back with part of the pressed fish and water, so it leads to high VBN (generally between 150-250), high acidity of histamine and slightly reddish-brown fishmeal, with fine character, protein generally between 60%-66%, acidity relatively high compared with defatted fishmeal, pepsin digestibility between 80-90, and salinity between 4.5-5.5%. The salt content is between 4.5 -5.5. The odor of semi-skimmed fishmeal and skimmed fishmeal is quite different, with a slightly rancid odor. Semi-skimmed costs much less than skimmed.
3. Full-fat fishmeal: The production process of full-fat fishmeal is that the fish is cooked by the cooking machine and then the fish and water together go directly into the dryer for drying, without pressing, the water and the cooked fish go directly into the drying tank. Since semi-skimmed fishmeal and full-fat fishmeal do not require high freshness of raw fish, the oil content of fish will be very little, and the fat content is relatively high compared with that of skimmed fishmeal, the fishmeal produced is very fine in shape, the protein content is between 55%-62%, VBN is generally between 200-500, the acidity is relatively high, the digestibility of pepsin is between 80-90, and the salt content is relatively high, and the quality is relatively high compared with that of skimmed fishmeal, therefore the quality is relatively high. In terms of odor, it is very different from skimmed fishmeal, so the quality is worse than semi-skimmed fishmeal.