Fatty acid and amino acid composition of raw and hot smoked sturgeon (Huso huso,L. 1758)

Changes in fatty acid and amino acid composition in hot smoked sturgeon (Huso huso, L. 1758) were studied. The sturgeon was smoked for 20 min at 30°C, followed by 90 min at 50°C and 40 min at 80°C. The palmitic acid (C16:0) and stearic acid (C18:0) increased (P<0.05) from 17.70% to 27.52% and from 7.49% to 13.63% after smoking, respectively. The oleic acid content in smoked sturgeon decreased from 28.29% to 25.93%, but no change (P>0.05) was observed in the total monounsaturated fatty acid composition of fish after smoking. Total polyunsaturated fatty acid, eicosapentaenoic acid and docosahexaenoic acid contents decreased from 21.03% to 4.93%, from 4.65% to 0.49% and from 12.41% to 0.51% in sturgeon after smoking, respectively. The total n-3 and n-6 contents and the n-3/n-6 ratio of raw and smoked sturgeon were 17.48–1.35, 3.54–3.58 and 4.94–0.38, respectively. The atherogenic index and index of thrombogenicity values of raw and smoked sturgeon were determined as 1.01–0.31 and 1.93–1.24, respectively. The smoking process caused an increase (P<0.05) in aspartic acid>isoleucine>methionine>hidoksil-l-proline>valine, and a decrease (P<0.05) in glutamic acid>serine>threonine>leucine>tyrosine>histidine>lysine>proline. However, the changes in alanine, glycine and phenylalanine were insignificant (P>0.05).     

Comparison of fatty acid,mineral and proximate composition of body and legs of edible frog (Rana esculenta)

The fatty acid profile and mineral composition (calcium, magnesium, sodium, phosphorus, potassium, iron, zinc, manganese, silicon, boron, cadmium, chromium, nickel, aluminium, copper, and lead) by Inductively Coupled Plasma-Atomic Emission Spectometry (ICP-AES) and the proximate composition of the body and legs of edible frog (Rana esculenta) were investigated. The fatty acids occurring in the highest proportions in both the body and leg of frogs were mystiric acid (C14:0, 1.13–2.30%), palmitic acid (C16:0, 19.76–23.23%), stearic acid (C18:0, 3.61–6.29%), palmitoleic acid (C16:1, 7.06–13.08%), oleic acid (C18:1n-9 cis, 10.83–16.71%), linoleic acid (C18:2n-6, 6.44–6.71%), γ-linolenic (C18:3n-6, 0.13–0.27%), linolenic (C18:3n-3, 2.32–3.37%), cis-11,14,17-eicosatrienoic acid (C20:3n-3, 4.71–7.72%), cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n-3, 3.96–6.05%) and cis-4,7,10,13,16,19-docosahexaenoic acid (C22:6n-, 2.77–6.67%). Among the minerals determined, potassium was found to be highest, followed by phosphorus. Calcium, aluminium, cadmium, copper, lead, chromium, nickel, boron, silicon and zinc are found to be lower than the potential toxicity levels.     

Effect of processing on proximate composition,anti-nutrient status and amino acid content in three accessions of African locust bean (Parkia biglobosa (jacq.) benth

Proximate composition, amino acid levels and anti-nutrient factors (polyphenols, phytic acid and oxalate) in the seeds of Parkia biglobosa were determined at three stages: raw, boiled and fermented. The highest anti-nutrient factor present in the raw state was oxalate, while phytic acid was the least. The amino acid of the raw seeds matched favourably to the World Health Organization reference standard. After processing, boiling increased fat, crude fibre and protein, while it reduced moisture, ash and the anti-nutrient content in 64% of the cases examined. Fermentation reduced ash, crude fibre and carbohydrate in all the accessions. It increased the moisture, fat and protein, while reducing the anti-nutrient factors in 78% of the cases. The high levels of protein, fat and amino acids coupled with the low levels of the anti-nutrients in the boiled and fermented seeds make Parkia a good source of nutrients for humans and livestock.     

The effect of using different probiotic cultures on conjugated linoleic acid (CLA) concentration and fatty acid composition of white pickle cheese

Pickle white cheeses were produced from whole milk with five different probiotic cultures (Enterococcus faecium, Lactobacillus paracasei, Bifidobacterium longum, Bifidobacterium bifidum and Lactobacillus acidophilus). Conjugated linoleic acid (CLA) content of cheeses ranged from 3.52 to 3.92 mg/g. Probiotic differences and storage process have not affected the CLA contents of the samples statistically. There was no correlation between the CLA content of all probiotic cheeses and saturated fatty acids. A positive correlation between the CLA and linoleic acid contents of L. paracasei and L. acidophilus cheeses was observed.     

Seasonal Variations in Fatty Acid Composition and the N-6/N-3 Fatty Acid Ratio of Pikeperch (Sander LUCIOPERCA) Muscle Lipids

Total lipid, fatty acid composition and the N-6/N-3 fatty acid ratios of muscle of pikeperch (Sander lucioperca) was determined once every two months. The ratio of unsaturated fatty acids (UFA) was higher than half of the total fatty acid content, and the monounsaturated fatty acid (MUFA) was higher than the polyunsaturated fatty acid (PUFA) ratio. The n-3 fatty acids were present in excess of the n-6 fatty acids. Eicosapentaenoic (EPA), docosahexaenoic (DHA), and arachidonic (AA) acids were the most abundant PUFA. The fatty acid composition and n-6/n-3 fatty acids ratio in the muscle of pikeperch are significantly influenced by spawning and the season. Relative proportions of PUFA (especially n-3 fatty acids) diminished significantly with the maturation of gonads. The ratio of n-6/n-3 fatty acids was less than one except during the reproduction period. This result suggests that meat quality of pikeperch is very good except during the spawning period with respect to the n-6/n-3 fatty acids ratio.     

Characterization of cod (Gadus morhua) frame composition and its valorization by enzymatic hydrolysis

This study aimed at evaluating proximate composition, phosphorous content, amino acid (AA) and fatty acid (FA) profiles of cod (Gadus morhua) frame at five different sampling times (March 2017 to March 2018). Furthermore, the valorization possibility of cod frame by application of enzymatic hydrolysis was investigated using the samples from September 2017. In terms of protein content, this sample showed a significantly (P < 0.05) higher level (16.5 %) compared to the other samples, whereas lipid and phosphorous contents varied in a narrow range of 0.9–1.1 % and 2.9–4.4 %, respectively, (P < 0.05). Furthermore, the total amino acids (AAs) content varied from about 98–155 mg/g in minced cod frame. Enzymatic hydrolysis of minced cod frame (MCF) and heated cod meat (HCM) was carried out by application of Alcalase and Neutrase, either individually or sequentially to obtain fish protein hydrolysate (FPH) and bone powder rich in phosphorus and calcium. The protein content of FPH varied from 76 % to 84 % and soluble-nitrogen in trichloroacetic acid (SN-TCA) index varied from 30.6 to 40.3%, resulting in similar trends for yield and nitrogen recovery. Considerable amounts of phosphorus and calcium (330 and 583 g/kg, respectively) were recovered from the cod frame bones after enzymatic hydrolysis. This study showed that it is possible to produce bone powder rich in phosphorous and calcium as well as peptides from the cod frame. Thus, the cod frame side-stream can be converted from its current use as mink feed ingredient into higher value products for human consumption, without generating new waste products.     

Comparison of the nutrient composition,biogenic amines and selected functional parameters of meat from different parts of Nile crocodile (Crocodylus niloticus)

The aim of the study was to compare nutritional parameters (contents of fat, protein and the individual amino acids), biogenic amines (histamine, tyramine, phenylethylamine, tryptamine, putrescine, cadaverine, spermidine and spermine) content, selected functional properties (colour and textural properties) and pH values of six parts of crocodile carcass (tail dorsal – TD, tail ventral – TV, neck – N, shoulder – S, leg – L and cheek – C). The individual parts of the crocodile carcass showed different values of nutritional parameters. TD and C had the highest values of Essential Amino Acid Index (104–126). Valine, threonine and leucine were determined as limiting amino acids in individual parts of the crocodile carcass. The content of biogenic amines was very low. These results will provide crocodile meat producers as well as consumers with new and useful information about the nutritional value of this meat and its relevance for nutrition.     

Variation and inheritance of oil content and fatty acid composition in niger (Guizotia abyssinica)

Niger (Guizotia abyssinica) is an economically important edible oilseed crop with a wide variation in seed oil content and fatty acid composition between populations. This study sought to determine the extent of this variation among the Ethiopian niger populations and to analyze the inheritance of high oil and oleic acid (C18:1) contents. The analysis of 153 niger populations revealed a twofold variation in seed oil content (27–56%) with 7% of the populations having more than 50% oil. These high oil content populations came from different regions and a wide altitudinal range (1400–2590 m asl). There was also a high variation in oleic acid content between populations (3.3–31.1%). Interestingly, the populations with more than 13% oleic acid were entirely collected from elevations of less than 2000 m asl. Breeding of selected genotypes for two generations revealed a highly significant positive correlation between the parents and their progenies both in oil and oleic acid contents. The study also suggests a significant contribution of environmental factors to the variation in both traits suggesting a moderate heritability. We conclude that there is a highly significant variation both in oil content and fatty acid composition in the niger populations that can be used for its improvement.     

Proximate composition and fatty acid profile of edible tissues of Capoeta damascina (Valenciennes, 1842) reared in freshwater and brackish water

This study aimed to determine the proximate composition and fatty acid profile of edible tissues of Capoeta damascina reared in freshwater and brackish water. The Juveniles of freshwater originating C. damascina were acclimated to brackish water of different salinities (6, 12, and 24 g/l); and grown in same conditions as their counterparts in freshwater. Increase in salinity led to higher moisture and lower lipid content (P < 0.05) in muscle, but had no marked impact (P > 0.05) on proximate composition of liver. In both tissues, the contents of total polyunsaturated fatty acids (PUFAs) and n-3 PUFAs were significantly (P < 0.05) increased, while the content of total monounsaturated fatty acids (MUFAs) was significantly decreased (P < 0.05) by increase in salinity. The contents of eicosapentanoic acid (EPA, 20:5 n-3), docosahexanenoic acid (DHA, 22:6 n-3), and arachidonic acid (20:4 n-6) were significantly increased (P < 0.05), while linoleic acid (18:2 n-6) and α-linolenic acid (18:3 n-3) were significantly decreased (P < 0.05) by salinity. Considering the contents of fatty acids in 100 g of edible portions, fillets of C. damascina reared in 6 and 12 g/l salinities as well as freshwater group were good sources of n-3 PUFAs particularly EPA and DHA.     

Docosahexaenoic acid (DHA) at the sn-2 position of triacylglycerols increases DHA incorporation in brown,but not in white adipose tissue,of hamsters

We hypothesised that the incorporation of docosahexaenoic acid (DHA) across adipose tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position. Ten-week old male hamsters were allocated to 4 dietary treatments (n?=?10): linseed oil (LSO-control group), fish oil (FO), fish oil ethyl esters (FO-EE) and structured DHA at the sn-2 position of TAG (DHA-SL) during 12?weeks. In opposition to the large variations found for fatty acid composition in retroperitoneal white adipose tissue (WAT), brown adipose tissue (BAT) was less responsive to diets. DHA was not found in subcutaneous and retroperitoneal WAT depots but it was successfully incorporated in BAT reaching the highest percentage in DHA-SL. The PCA on plasma hormones (insulin, leptin, adiponectin) and fatty acids discriminated BAT from WATs pointing towards an individual signature on fatty acid deposition, but did not allow for full discrimination of dietary treatments within each adipose tissue.     

Proximate, unsaponifiable lipid and fatty acid composition of bogue (Boops boops) and horse mackerel (Trachurus trachurus) from the Italian trawl fishery

This study was aimed at evaluating the nutritional properties of bogue (Boops boops) and horse mackerel (Trachurus trachurus), fish species present throughout the Mediterranean and highly represented in the catch of the Italian trawl fishery. In Italy such fish species are scarcely known by consumers and are not sought-after on the market, especially when the fish are small. Proximates, unsaponifiables and fatty acid profile of bogue and horse mackerel caught by trawlers in different seasons of the year along the southern Adriatic coast of Italy were evaluated. Results showed that both species were characterised by good protein contents (18–20 g/100 g) and low lipid (1–2 g/100 g) and cholesterol (50–70 mg/100 g) levels at any season considered. Along with α-tocopherol (0.45–0.70 mg/100 g), δ-tocopherol was found at a lower level (0.04–0.09 mg/100 g) while no detectable amounts of the γ-isomer were observed in either species. The fatty acid profiles of horse mackerel and bogue exhibited a seasonal fluctuation. They were characterised by high proportions of polyunsaturated fatty acids (PUFA), ranging from about 30% of total fatty acids in summer to more than 40% of total fatty acids in spring and winter, and by high n-3/n-6 PUFA ratio values (4.4–6.8 for bogue, 7.4–8.2 for horse mackerel). On a quantitative basis, in bogue total n-3 PUFA amounted to 0.29–0.43 g out of 0.33–0.54 g of total PUFA per 100 g wet fillet. In horse mackerel total n-3 PUFA ranged between 0.37 g and 0.43 g/100 g and total PUFA between 0.41 and 0.49 g/100 g wet fillet. The atherogenic (0.46–0.63) and thrombogenic (0.22–0.38) indexes calculated on bogue and horse mackerel were comparable to those of fish species of higher commercial value. The nutritional properties of these underutilised species may be considered comparable to those of other low-fat fish species from the wild and also from aquaculture present on the Italian market and meeting consumers’ preferences.     

Analysis of protein amino acids,non-protein amino acids and metabolites,dietary protein,glucose, fructose,sucrose, phenolic,and flavonoid content and antioxidative properties of potato tubers,peels, and cortexes (pulps)

The composition and antioxidative activity of whole potato tubers from five Korean cultivars, three peels from one cultivar, and eight pulps (cortexes) after peeling from six different cultivars were evaluated. Whole tubers were sectioned into three parts followed by analysis of the peels and pulps of each part. The following characteristics were determined: the dimensions and water content of whole tubers; nutritional protein content consisting of protein and free amino acids by an automated Kjeldahl nitrogen assay; free non-protein amino acids, metabolites, and fructose, glucose, and sucrose content by HPLC; phenolic compounds by HPLC and LC/MS; total phenolics and flavonoids by colorimetry; and antioxidative properties by ABTS, DPPH, and FRAP assays. The results demonstrate differences and similarities in the content of nutritional and bioactive compounds and in their bioactivities from whole potatoes, peels, and pulps. The present study reports for the first time the analysis of multiple potato nutrients and bioactive components as well the antioxidative properties of whole potatoes, peels, and pulps derived from the same tubers. The described methods are expected to facilitate the analysis of commercial and newly-developed potato cultivars, peels, and pulps and relate their composition and antioxidative activities to their reported nutritional, health-promoting, and industrial properties.