Marian Naczk

The effect of methanol-ammonia-water treatment on the content of phenolic acids of canola

Abstract The contents of free, esterified and insoluble-bound phenolic acids of meals produced by methanol-ammonia-water/hexane treatment of canola seed were determined and compared with those of hexane-extracted meal. Ground seeds were extracted by the two-phase solvent extraction system consisting of 10% ammonia in methanol or 10% ammonia in methanol containing 5% water, and hexane as the second phase. The two-phase solvent extraction system removed 82% and 50% of the esterified and free phenolic acids originally present in the seed, respectively. However, the concentration of insoluble-bound phenolic acids was not affected.

Chemical composition and nutritional value of processing discards of cod (Gadus morhua)

Cod offal from Atlantic species (Gadus morhua) during the intense summer inshore fisheries, June–August, was analyzed for its chemical composition and energy value. The crude protein content of the samples was 14·3% and this included 2·55% collagen. The total lipid content of the offal was 4·3% and its ash content averaged 3·95%. Thus, the energy value of the offal was calculated as 413 kJ/100 g. The offal had an increased content of glycine, alanine, serine, proline and hydroxyproline as compared to the cod muscle proteins. Based on the content of selected amino acids, the calculated PER value for the offal was 1·88–2·36 as compared to 2·86–3·24 for the cod muscle. The fatty acid composition of the offal was similar to that of the cod-liver oil.

Insensitivity of the amino acids of canola and rapeseed to methanol-ammonia extraction and commercial processing

Abstract Amino acid composition of rapeseed meals treated with ammonia in absolute or 95% methanol was compared to those of their hexane-extracted counterparts as well as a commercially processed meal. Meals of Altex canola, Midas rapeseed, and Hu You 9 Chinese rapeseed were used. Few differences were found in the essential amino acid contents due to these treatments. Partial extraction of non-protein nitrogen compounds may be responsible for the observed differences. Protein efficiency ratio (PER) values of meals, calculated on the basis of the content of selected amino acids, varied from 1.7 to 2.4, depending on the seed variety. The processing conditions did not affect the calculated PER values to any great extent.

Seal Meat – A Potential Source of Muscle Food: Chemical Composition, Essential Amino Acids and Colour Characteristics

Abstract Meat from harp seal ( Phoca groenlandica ) carcasses was separated by manual or mechanical deboning. The yield by manual separation of meat from dressed carcasses was 22–30% and this was increased to 80–88% by mechanical deboning. Crude protein content of the samples varied between 21.58–24.32% and this included a total hemoprotein content ranging from 5.28–9.08%. The content of total lipids, ash and collagen in the mechanically separated seal meat was higher than those in the manually separated samples. The content of essential amino acids in seal meat was generally higher or equal to those in beef and pork. The Hunter colour parameters of raw seal meat samples were L = 14.4–17.2, a = 2.0–5.2 and b = 0.9–2.2, thus reflecting the dark colour of the muscles.

Extraction and Concentration of Omega-3 Fatty Acids of Seal Blubber

Seal blubber lipids consist of approximately 99% neutral triacylglycerols and 1% polar components. Blubber lipids contained 24% long-chain omega-3 fatty acids consisting of approximately 9% eicosapentaenoic acid (EPA), 5% decosapentaenoic acid (DPA), and 10% docosahexaenoic acid (DHA). The content of DPA was higher in seal blubber lipids as compared with other sources of marine oil, except mammalian species. Intramuscular lipids of seal meat were also rich in their content of DPA and other omega-3 fatty acids. Omega-3 concentrated blubber lipids containing 76% long-chain omega-3 fatty acids were prepared by extraction/precipitation of saturated/monounsaturated lipid fatty acids. Stability of seal blubber lipids was better than that of fish oils.