Biochemical, Mineral, and Vitamin Composition of Belarusian Linseed Cultivars

Linseeds are a promising source of biologically valuable substances, essential amino acids, dietary fiber, vitamins, antioxidants, and essential polyunsaturated fatty acids. The article describes the biochemical, mineral, and vitamin composition of Belarusian flax varieties. The research objective was to select cultivars for functional food production. The study featured ten linseed cultivars, i.e., Ilim, Opus, Brestskiy, Salut, Fokus, Allyans, Dar, Vizir, Slavyanin, and Bonus. In 2020–2021, the authors planted plots of 1 m2 in triplicate for each cultivar. The experimental field belonged to the Institute of Flax, Ustye, Republic of Belarus. The study followed standar d methods to determine the content of micronutrients. All flax varieties proved to be a reliable source of vegetable fat (≤44.8%), protein (≤25.1%), and fiber (≤26.0%). The maximal content of α-linolenic acid belonged to Salut (63.0%), Vizir (61.4%), and Bonus (61.8%). The average mineral content was as follows: 7,500.0–10,625.0 mg/kg potassium, 5,700.0–7,522.5 mg/kg phosphorus, 2,300.0–2,605.0 mg/kg magnesium, 1,200.0–1,922.5 mg/kg calcium, 45.0–56.0 mg/kg iron, and 124.5–190.0 mg/kg sodium. The maximal content of vitamin B1 was registered in the samples of Salut (0.91 mg/100 g) and Brestskiy (1.08 mg/100 g); the maximal content of vitamin B2 belonged to the samples of Dar (0.058 mg/100 g), Ilim (0.057 mg/100 g), and Brestskiy (0.056 mg/100 g); the maximal content of vitamin E (tocopherol) was found in the samples of Salut (12.6 mg/100 g), Dar (12.07 mg/100 g), and Opus (12.35 mg/100 g). The linseeds were not suitable for high-quality food flour production after room temperature storage because the acid number increased by 64–73%. The excellent biological value of Belarusian flax cultivars demonstrated good prospects as highly active functional ingredients in new functional foods.