The Nutritional Value of the Soluble and Solid Fractions of Stickwater Derived from Fishmeal Production Process of Kilka for Use in Aquafeed

Shahmohammadpour Askari, Mohammad Mehdi; Mirzakhani, Mohammad Kazem; Abediankenari, Abdolmohammad

doi:10.48311/jfst.2025.117266.82457

The Nutritional Value of the Soluble and Solid Fractions of Stickwater Derived from Fishmeal Production Process of Kilka for Use in Aquafeed

Document Type : Original Research

Authors

Mohammad Mehdi Shahmohammadpour Askari ^¶

Mohammad Kazem Mirzakhani

Abdolmohammad Abediankenari

Department of Aquaculture, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran, Iran

10.48311/jfst.2025.117266.82457

Abstract

Stickwater, a nutrient-rich byproduct of the fishmeal production process, consists of two phases soluble and solid each with potential applications in livestock and aquafeeds. This study evaluated the chemical composition, including proximate analysis, amino acid profile, and fatty acid composition, of both the soluble and solid phases of stickwater. Samples were collected from a Kilka fishmeal processing factory, and both fractions were analyzed for protein, lipid, ash, moisture, amino acids, and fatty acids. The results showed that the solid phase was richer in protein (70.73%) and lipid (17.61%), and contained higher levels of non-essential amino acids such as glycine. In contrast, the soluble fraction in addition to the relatively high protein content (67.2%), exhibited the highest levels of long-chain polyunsaturated fatty acids (HUFA), including EPA, DHA, and ARA, along with superior concentrations of essential amino acids such as leucine and isoleucine, identifying it as a valuable nutritional source. The findings demonstrate that the soluble and solid phases of stickwater possess complementary yet distinct nutritional potentials. The soluble phase can be utilized as a rich source of HUFA and essential amino acids during critical rearing stages, while the solid phase serves as an effective source of protein and energy in basal aquafeeds.

Keywords

Stickwater

nutritional composition

amino acids

fatty acids

fisheries by-product

Subjects