Sunflower meal is the by-product of the extraction of oil from sunflower seeds. In terms of production, A wide variety of products are available on the market, from low-quality straw-like meals to high-quality flours. Sunflower meals can be made from whole or decorticated seeds, and can be mechanically and/or solvent-extracted.
Sunflower meal is one of the major protein meals used for livestock feeding, particularly for ruminants. It is generally a valuable and safe product, whose protein, fiber and oil contents are highly variable and driven by variations of the oil extraction process. Its protein content ranges from 23% DM for some non-dehulled, mechanically-extracted meals, to more than 40% for highly decorticated, solvent-extracted meals. However, usual ranges for protein are 29-33% DM for non-dehulled meals and 35-39% DM for dehulled and partially dehulled meals. The fiber content is directly linked to the presence of hulls: crude fibber ranges from 27 to 31% DM for non-dehulled meals and from 20 to 26% for dehulled and partially dehulled sunflower meals. The lignin content is important, in the 9-12% range, even for dehulled meals. Solvent-extracted sunflower meals contain about 2-3% DM of residual oil, but mechanically-extracted meals may contain up to 30% oil depending on the amount of pressing.
One particularly interesting trait of sunflower meal is the absence of intrinsic antinutritional factors: unlike other oil meals, including those of soybean, rapeseed or cotton, it does not require heating or special attention before being fed. Its amino acid profile is richer in sulfur-containing amino acids, particularly methionine, than other protein sources, but its lysine content is much lower than that of soybean meal
The high fiber and lignin content of sunflower meal tends to reduce nutrient digestibility, and its energy values are lower than those of soybean meal. It is suitable for ruminants and rabbits, but only for pigs and poultry with low energy requirements (animals at maintenance, laying hens) or specific fiber requirements (sows). In other monogastric, such as broilers or growing pigs, the cost-effectiveness of including sunflower meal depends on the quality of the meal and on the availability and price of better sources of protein and lysine. It must be reiterated that sunflower meal is a highly variable ingredient where protein, fiber and fat cover a much larger range than in many common feeds.