Milt refers to the reproductive fluid of male fish and certain other aquatic animals. It is primarily composed of spermatozoa and is sometimes called soft roe, serving as the male counterpart to the more widely recognized fish eggs, or hard roe. This substance holds an intriguing position, being both a fundamental component of aquatic reproduction and a delicacy in various global cuisines.
Biological Function and Composition
Milt plays a fundamental role in the reproductive cycle of many aquatic species. It is the seminal fluid produced by male fish, containing the spermatozoa necessary for fertilization. This fluid is released into the water during spawning, where it disperses to fertilize the eggs (roe) laid by female fish in a process known as external fertilization. The milky white appearance of milt is characteristic of its composition.
Beyond its primary reproductive function, the physical and chemical makeup of milt varies by species. Its composition varies by species, but it is generally high in water and protein. It comprises various essential biological molecules, including DNA, amino acids, and proteins, which are important for spermatozoa viability and function. In aquaculture, milt is manually collected from male fish, such as Pacific salmon, and used to fertilize harvested eggs in controlled environments, aiding in captive breeding programs.
Milt’s Culinary Applications
Globally, milt is recognized as a culinary ingredient, often considered a delicacy in numerous cuisines. In Japan, it is known as “shirako,” meaning “white children,” and is prized, especially in winter. Its texture is often described as creamy, delicate, or custard-like, with a subtly sweet or mild oceanic flavor. Shirako can be prepared in various ways, including being served raw with ponzu sauce, lightly fried as tempura, grilled, or incorporated into hotpots and steamed egg custards (chawanmushi).
Beyond Japan, milt finds its place in other culinary traditions. In Romanian cuisine, carp milt is called “lapți” and is typically fried. Russian cuisine features pickled herring milt, known as “moloka,” which is sometimes eaten separately or combined with pickled herring roe. In Sicily, tuna milt, referred to as “lattume,” is used as a topping for pasta dishes. Traditional British cooking also includes cod soft roes, often fried in butter and served on toast.
Nutritional Aspects and Consumption Notes
Milt offers a distinctive nutritional profile, contributing various beneficial compounds. It is a source of protein, important for tissue maintenance and repair. Milt also contains healthy fats, including Omega-3 fatty acids, recognized for their contributions to heart health.
Milt provides a range of vitamins and minerals. These include B vitamins, such as B12, which supports brain function and DNA synthesis, as well as phosphorus, magnesium, and zinc. Some varieties, like herring milt, are notable for their arginine content, an amino acid, and marine DNA. When considering consumption, particularly for raw preparations, proper handling and preparation are important to ensure safety and maintain quality. The unique texture and flavor of milt can be an acquired taste for some.