Cold pressing of flaxseed produces high-quality oil along with a nutritionally rich by-product—flaxseed cake. While the cold-pressing process is valued for its minimal processing and preservation of oil quality, it is also characterized by low resource utilization efficiency and significant by-product generation. Specifically, the production of 1 kg of flaxseed oil results in approximately 2 kg of residual cake. Given its high protein content (approximately 35–40%), flaxseed cake holds considerable potential as a source of bioactive peptides and other value-added compounds
In this study, flaxseed cake obtained from cold pressing was milled and sieved to a particle size below 0.6 mm. Its chemical composition (protein, oil, fiber) was analyzed. Controlled enzymatic hydrolysis was performed with Trypsin for 2 h. An E/S ratio was 5 %, and the temperature used for hydrolysis was 37 °C. The antioxidant capacity of the non-hydrolyzed sample and hydrolysate was determined.
Protein content was 37 %, oil was about 21 %, and fiber was approximately 28 %. The results showed a degree of hydrolysis of about 5 % and a significant increase in antioxidant activity. By determining the concentration of flaxseed powder required to inhibit 50 % of the DPPH free radicals, it was observed that this concentration was significantly (p < 0.05) higher in the non-hydrolyzed sample (11.0 mg/mL) compared to the hydrolysate (9.1 mg/mL).
Conceptualization, T.K.; Investigation, T.K.; Writing – original draft, T.K. All authors have read and agreed to the published version of the manuscript.
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Citation
Funding Statement
This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (Contract No. 451-03-136/2025-03/200287) and UNDP in Serbia through the Circular voucher (Contract No.00131890/1138320/2024/01-03). Sincere thanks to Linum d.o.o. for their trust and for providing the raw materials used in this work.
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