Oil composition,mineral nutrient and fatty acid distribution in the lipid classes of underutilized oils of Trilepisium madagascariense and Antiaris africana from Nigeria

Trilepisium madagascariense (TM) and Antiaris africana (AA) are two underutilized plants from Nigeria. They have been subjected to standard analytical techniques in order to evaluate the proximate composition, physico-chemical properties, mineral nutrient, fatty acid composition and distribution in the lipid classes of the seeds and seed oils. The carbohydrate composition of these seeds are high; TM is 62.73 ± 0.30% and AA is 53.97 ± 0.50%. Iodine value of TM was found to be 46.10 ± 0.70 mg iodine/g while that of AA was 88.24 ± 0.50 mg iodine/g. The mineral composition of the seeds and the oils varied with K having the highest concentration in the seed and Na the highest concentration in the oils. Linoleic acid is the dominant fatty acid in the oil of AA with the highest composition in the neutral lipids while palmitic acid is the dominant fatty acid in oil of TM. Vitamin E, Gamma-Sitosterol, α and β-Amyrin, Lupeol, Stigmast-4-en-3-one, and hydrocarbons were isolated from these oils. The results of the proximate, mineral nutrient compositions, chemical characterization and fatty acid distribution of these seeds and seed oils shows their possibility as potential resources.     

Polar lipids,sphingomyelin and long-chain unsaturated fatty acids from the milk fat globule membrane are increased in milks produced by cows fed fresh pasture based diet during spring

Milk lipids are an interesting source of bioactive molecules with functional and nutritional properties. Although the composition of milk lipids is of utmost importance for food processing and human consumption, it is far from being fully known. The objective of this study was to perform a comparative analysis of the chemical composition of lipids from bovine milks produced in French Brittany during spring (fresh pasture based diet) and winter (corn silage based diet). The polar lipid content and relative proportions of the glycerophospholipids and sphingomyelin were determined using HPLC/ELSD. The fatty acid composition of total lipids and polar lipids was determined using GC. The milks collected in spring contained i) a lower amount of total lipids: 39.7 ± 0.8 g/kg vs 41.7 ± 0.5 g/kg in winter, ii) a higher amount of polar lipids: 138 ± 11 vs 112 ± 8 mg/kg milk; 3.5 ± 0.3 vs 2.7 ± 0.4 mg/g fat, which was related to a smaller size of fat globules, and iii) a higher amount of sphingomyelin, 32 mg/kg milk vs 25 mg/kg milk in winter. Interestingly, the polar lipids from the milk fat globule membrane contained a higher concentration of unsaturated fatty acids in spring (C18:1 n − 9, C18:2 n − 6, C18:3 n − 3 and long-chain n − 3 fatty acids). Milk from cows fed a fresh pasture-based diet during spring is an interesting source of dietary long chain polyunsaturated fatty acids for human consumption.     

Oil content and fatty acid composition of some underutilized legumes from Nigeria

Three underutilized legumes from Nigeria, Brachystegia eurycoma, Tamarindus indica and Mucuna flagellipes, have been subjected to standard analytical techniques in order to evaluate proximate composition, physicochemical properties and contents of nutritional valuable elements and fatty acids of the seeds and oils. The proximate analysis indicated that the oil content was 5.87 ± 0.30, 7.20 ± 0.45 and 3.77 ± 0.21 g/100 g for B. eurycoma, T. indica and M. flagellipes, respectively. The seeds are rich in protein and carbohydrate, the protein content ranging from 11.82 ± 0.25 g/100 g–24.94 ± 0.18 g/100 g dry matter. These compare favourably with high protein animal sources like oyster, beef, pork and marine fishes. The iodine value of two of the oils place them in the non-drying group of oils, while the composition of all the oils compare well with those of rape seed, sesame, sunflower and groundnut seed oils. This suggests their use as edible oils.Analyses of the oils for fatty acids indicate that the oils contain linoleic acid which is one of the three essential fatty acids. The dominant fatty acids however are linoleic, palmitic, oleic and stearic acids with oleic acid having the highest percentage 24.13–31.50%. Eight nutritional valuable minerals were determined in the seed flours. The seeds are rich in potassium 52.1 mg/100 g–131 mg/100 g. They also contain significant concentration of iron 4.55 mg/100 g–8.20 mg/100 g.     

A novel approach to monitor the oxidation process of different types of heated oils by using chemometric tools

The oxidative stability of seven oils with different fatty acid profiles was assessed. Oxidation at 0, 2 and 4 h at 180 °C was monitored by measuring the absorbance of thiobarbituric acid reactive substances (TBARS) along the absorption spectrum (300–600 nm), the volatile aldehydes (HS-SPME–GC–MS) and the fatty acid profile (FID-GC).TBARS absorption spectrum behavior depended on the lipid composition of heated oils. Higher absorbance increments during heating were noticed at 390 nm compared to 532 nm (from 2 to 21 fold higher depending on the oil), pointing to its better sensitivity to detect oxidation. Furthermore, a close relationship between ABS₃₉₀, the loss of polyunsaturated fatty acids and their corresponding oxidation compounds (volatile aldehydes) was revealed by Principal Component Analysis.Multiparametric equations allowed predicting the formation of volatile aldehydes of heated oils by measuring only two parameters: TBARS₃₉₀ during their heating, and the lipid profile in unheated oils (MUFA, ω-3 and ω-6). Results pointed out the interest of choosing ABS₃₉₀ when the oxidative evolution of vegetable oils under heating is assessed by the TBARS test.     

Conjugated linoleic acid (CLA) concentration,fatty acid composition and cholesterol content of some Turkish dairy products

Conjugated linoleic acid (CLA) concentrations, fatty acid composition and cholesterol content of some Turkish dairy products (butter, processed cheese, Kaymak and cream) were determined by capillary gas chromatography. The CLA and cholesterol content of some Turkish dairy products ranged from 1.50–5.60 mg/g fat and 148.30–369.04 mg/g fat, respectively. The most abundant saturated fatty acids in the dairy products investigated were palmitic acid (C16:0), stearic acid (C18:0) and myristic acid (C14:0). In all dairy products, C18:1 cis-9, 12 unsaturated fatty acid content (23.12–32.78 g/100 g) was considerably higher than others. In all samples studied, there was no correlation between CLA content of products and the linoleic acid content, or any other unsaturated fatty acid. A positive correlation between cholesterol and fat content of dairy products was observed.     

Fatty acid composition of lamb meat from the autochthonous Jezersko–Solčava breed reared in different production systems

Thirty two autochthonous Jezersko–Solčava lambs were used to investigate the effect of production (pasture vs. stable) and weaning system (suckling vs. weaned) on fatty acid composition of Longissimus dorsi intramuscular fat in a 2 × 2 factorial design. Pasture lambs had lower intramuscular fat concentration (P < 0.0001) more PUFA and trans C18:1, more ALA (P = 0.0322), ARA (< 0.0001) and EPA (0.0149) but less SFA (P < 0.0001) than stable lambs. Weaning system affected PUFA (P = 0.0040) and MUFA (P = 0.0070) but not SFA and trans C18:1 fatty acids. The interaction of production system and weaning system was significant mainly for trans C18:1 and trans C18:2 fatty acids. Finally, lamb meat from all four treatments which are traditionally used in rearing of Jezersko–Solčava lambs are favourable from the nutritive point of view, due to their low n − 6/n − 3 ratio.     

Lipid and protein oxidation of α-linolenic acid-enriched pork during refrigerated storage as influenced by diet supplementation with olive leaves (Olea europea L.) or α-tocopheryl acetate

The objective of this study was to evaluate the effect of diet supplementation with olive leaves or α-tocopheryl acetate on lipid and protein oxidation of raw and cooked n− 3 enriched-pork during refrigerated storage. Enrichment of pork with α-linolenic acid through diet supplementation with linseed oil enhanced (p ≤ 0.05) lipid oxidation in both raw and cooked chops but had no effect (p > 0.05) on protein oxidation during refrigerated storage while decreasing (p ≤ 0.05) the sensory attributes of cooked pork. Diet supplementation with olive leaves or α-tocopheryl acetate had no effect (p > 0.05) on the fatty acid composition of pork but decreased (p ≤ 0.05) lipid oxidation while exerting no effect (p > 0.05) on protein oxidation in both raw and cooked α-linolenic acid-enriched chops stored and chilled for 9 days. Moreover, olive leaves and α-tocopheryl acetate supplemented at 10 g/kg and 200 mg/kg diet, respectively, exerted (p ≤ 0.05) a beneficial effect on the sensory attributes of cooked α-linolenic acid-enriched pork chops.     

Effect of the addition of fatty acids on rice starch properties

The effect of the addition of the two fatty acids (stearic and linoleic acid) on starch pasting, thermal properties and the leaching of amylose during the gelatinization process are presented. The addition of stearic acid (C18:0) at 1.0% level (w/w, on the basis of starch) significantly changed starch pasting characteristics in peak viscosity (P < 0.05), breakdown (P < 0.001) and time to peak viscosity (P < 0.001) as measured by RVA. In contrast, the addition of linoleic acid (C18:2) showed less impact on the three RVA parameters. Thermal studies with DSC suggested that the addition of both fatty acids did not significantly influence the starch gelatinization behaviour as reflected in peak width and enthalpy but there was a decrease in peak temperature. However, the addition of the saturated fatty acid produced a significant decrease in the retrogradation endotherm (P < 0.01) compared to that of native starch. It is suggested that the saturated fatty acid complexes with amylose and is preferentially introduced into the starch granule. The double bond in the linoleic acid apparently hinders complexation. After complexation, hydrophobicity was further enhanced with the content of amylose in the hot-water soluble fraction being significantly reduced (P < 0.01) as determined by HPLC.     

Enrichment of the conjugated linoleic acid content of bovine milk fat by dry fractionation

This study investigated the effect of fat fractionation on the conjugated linoleic acid (cis-9, trans-11-C_18 : 2) content of bovine milk fat. Anhydrous milk fat was fractionated into hard and soft fractions using controlled cooling and agitation. Fractionation of milk fat pre-melted at 60°C using a temperature programme of 33–10°C and a cooling rate of 0.58°C h⁻¹ yielded a soft fraction containing 63.2% more conjugated linoleic acid (2.22 g 100 g⁻¹ FAME), which was also enriched in polyunsaturated fatty acids and vaccenic acid (trans-11-C_18 : 1) compared with the parent fat. Agitation following fractionation was found to have a negative effect on the conjugated linoleic acid content of the soft fraction. Refractionation of the soft fraction did not increase the yield of conjugated linoleic acid. The conjugated linoleic acid and trans fatty acid content of 26 selected food products ranging in milk fat content from 0 to 100% is reported. Conjugated linoleic acid concentrations ranged from 0 to 16.2 mg g⁻¹ fat and were generally lower than the trans fatty acid content which ranged from 0 to 155.7 mg g⁻¹ fat. Spreads containing vegetable oils contained higher trans fatty acid and lower conjugated linoleic acid contents than milk fat-containing products. This study highlights that a milk fat fraction enriched in conjugated linoleic acid may be achieved by dry fractionation.     

A comparison of the proximate compositions and fatty acid profiles of zander (Sander lucioperca) from two different regions and climatic conditions

The proximate compositions and fatty acid profiles of the flesh of the fresh water fish zander (Sander lucioperca) obtained from Eğirdir Lake and from Seyhan Dam Lake were compared. The crude protein (18.8–18.1%), ash (1.37–0.75), and dry matter (20.67–20.09) contents of fish in Seyhan Dam Lake were observed to be higher than those in the other lake. Zander in Seyhan Dam Lake had a significantly (p < 0.05) higher lipid content than its Eğirdir counterpart. Differences were also observed in the fatty acid profiles. The percentages of total saturated fatty acids (SFA) and total monounsaturated fatty acids (MUFA) were higher in the zander in Seyhan Dam Lake than in Eğirdir Lake, whereas the corresponding total polyunsaturated fatty acids (PUFA) content was lower. Moreover, the fatty acid composition of these fish showed a relatively high ratio of PUFA/SFA (1.00). Both zanders showed palmitic acid, C16:0, to be predominant, (19.6–20.8%), followed by oleic acid, C 18:1 n − 9, (19.2–13.4%).The data obtained indicate that the % composition of n − 3 PUFAs is greater in the flesh of zander in Eğirdir Lake. This finding is in compliance with the fact that n − 3 fatty acids in fish living in cold climatic conditions have a higher % composition. It was concluded that the consumption of zander, widely found in Eğirdir Lake and having higher % composition of n − 3 PUFAs than those caught from Seyhan Dam Lake, is more beneficial for human health.     

Determination of 5-hydroxymethyl-2-furfural and 2-furfural in oils as indicators of heat pre-treatment

This study describes a method for the determination of 5-hydroxymethyl-2-furfural (HMF) and 2-furfural (F) in oils. The method entails liquid–liquid extraction and reversed-phase liquid chromatography. Spiked hazelnut oil was used to test the accuracy and reliability of the method. Furan compounds were extracted from oil using 70% methanol. Mean recoveries were 97 ± 2% and 99 ± 1% for HMF and F, respectively. To investigate the presence of HMF and F in oils, seven oily nuts and seeds were roasted at 180 °C for 30 min. Different oils were found to contain HMF and F ranging from 0.8 to 13.8 and 1.4 to 8.7 mg/kg, respectively. Increasing solvent polarity also increased the rate of HMF transferred to the oil. Spectral analyses of the 70% methanol extracts indicated that absorbance at 285 nm may be used to monitor the accumulation of furan compounds in oil phase during the roasting process of nuts.     

The influences of carcass weight and depot on the fatty acid composition of fats of suckling Manchego lambs

The effects of carcass weight (<5.5 kg, 5.5–6.5 kg, ⩾6.5 kg) of Manchego suckling lambs, type of fat depot of the leg (subcutaneous, intermuscular and intramuscular) and muscle (m. longissimus dorsi (LD) or m. quadriceps femoris (QF)) on the fatty acid composition were studied. Carcass fatness increased with increasing carcass weight. However, few differences in fatty acid proportion were observed between the three carcass weight groups. The lightest carcasses had lower proportions of myristic (C14:0) and palmitoleic (C16:1) acid and higher proportions of stearic (C18:0) acid, desirable fatty acids (DFA) (C18:0 + total unsaturated fatty acid (TUFA)) and a greater nutritive value ((C18:0 + C18:1)/C16:0). The fatty acid composition of subcutaneous and intermuscular fat depots of the leg were similar, whereas the intramuscular fat depot was different from both of these, since it had a lower proportion of saturated fatty acids (SFA), a greater proportion of TUFA, higher PUFA/SFA and n − 6/n − 3 ratios, and greater DFA and nutritive values. The intramuscular fat of the LD was more saturated than QF, higher SFA, and had lower value of PUFA/SFA ratio and DFA. These results indicated that the intramuscular fat quality of the leg was better than subcutaneous and intermuscular fat depots and also that intramuscular fat displayed better attributes of quality (lower SFA, higher TUFA, and greater PUFA/SFA ratio and DFA as well) than intramuscular fat of the LD from the consumer health standpoint. Despite carcass weight affected carcass fatness, it did not seem to influence the proportions of saturated or polyunsaturated fatty acids. For this reason, carcass weight probably had little effect on the organoleptic characteristics of the meat.     

Polyphenolic and antioxidant content of white and blue corn (Zea mays L.) products

The polyphenolic and antioxidant content of white, Mexican blue, and American blue corns processed into nixtamal (cooked kernels), tortillas, and chips was investigated. A post-nixtamalization acidification treatment was assessed as a means to reduce polyphenolic and antioxidant losses. Similar anthocyanin composition (cyanidin 3-monoglycosides) and concentration (314 mg/kg) was observed for both blue corn genotypes as was their non-anthocyanin polyphenolic composition ((+)-catechin, free and esterified ferulic acid, and p-coumaric acid derivatives). Six derivatives of ferulic acid (88.8–816 mg/kg) along with the free form (2480 mg/kg), p-coumaric acid (6.6 mg/kg), two protocatechuic acid derivatives (4.2 and 14.2 mg/kg), and gallic acid (3.9 mg/kg) were identified in the white genotype. Both blue genotypes contained higher antioxidant capacity (>8.3 μmol Trolox equivalents/g) yet lower polyphenolic levels (3.6–4.4 g/kg) than the white genotype. Comparable anthocyanin losses were observed when the blue genotypes were processed into nixtamals (37%), tortillas (54%), and chips (78%) that correlated to polyphenolic (r = 0.91) and antioxidant capacity (r = 0.94) losses. Acidification was mainly effective in reducing anthocyanin (9–17%), polyphenolic (10%), and antioxidant capacity (6–14%) losses for the blue genotypes. This study compared polyphenolic and antioxidant content among corn genotypes and confirmed that acidification post-nixtamalization could reduce polyphenolic and antioxidant losses.     

Evolution of lipolysis during the ripening of traditional Feta cheese

Lipolysis was studied during ripening of traditional Feta cheese produced in two small dairies, A and B. The cheeses were made from a thermized mixture of ewes’/goats’ milk by using yoghurt as starter and artisanal rennet from lambs’ and kids’ abomasa (cheese A) or mixed artisanal rennet with calf rennet (cheese B).The acid degree value and the free fatty acids (FFA) contents in both cheeses increased sharply up to 18 d (pre-ripening period at 15 °C) and continued to increase throughout ripening. In both mature cheeses, acetic acid was found at high levels (13–18% of the total FFAs). However, except for this, all FFA contents differed significantly (P < 0.05) between the two cheeses throughout ripening. The levels of individual and total C2:0–C8:0, C10:0–C14:0 and C16:0–C18:2 fatty acids were significantly higher (P < 0.05) in cheese A than in cheese B. Presumably the difference, especially in the C2:0–C8:0 content, was due mainly to the type of the rennet used. Butyric acid was the dominant FFA in cheese A (20% of the total FFAs at 120 d), while the most abundant FFAs in cheese B were capric (18%) and lauric acid (18%). In general, the lipolysis degree of the two cheeses was higher than those reported for the industrially-made Feta cheese.In organoleptic evaluation, cheese A had a piquant taste that was attributed to its high content of butyric acid and showed a significantly (P < 0.05) higher total score than cheese B.     

Enriched n − 3 PUFA/konjac gel low-fat pork liver pâté: Lipid oxidation,microbiological properties and biogenic amine formation during chilling storage

Low-fat pork liver pâtés enriched with n − 3 PUFA/konjac gel were formulated by replacing (totally or partially) pork backfat by a combination of healthier oils (olive, linseed and fish oils) and konjac gel. Lipid oxidation, microbiological changes and biogenic amine (BA) formation were studied in healthier-lipid pâtés during chill storage (85 days, 2 °C). Increasing unsaturated fatty acid levels favoured lipid oxidation, although the levels reached were low throughout the storage period, ranging from 0.113 to 0.343 mg malonaldehyde/kg sample. Neither the formulation nor the time in storage affected the microbial load. Biogenic amine contents of products (the sum of initial concentrations and amines formed during storage) varied according to the type of BA but were far below levels that could constitute a consumer health hazard.     

Performance,carcass traits,muscle fatty acid composition and meat sensory properties of male Mahabadi goat kids fed palm oil,soybean oil or fish oil

This study examined the effect of palm, soybean or fish oils on the performance, muscle fatty acid composition and meat quality of goat kids. Twenty-four male Mahabadi kids (BW = 19.4 ± 1.2 kg) were divided into three groups according to liveweight and randomly allocated to one of three diets. Animals were fed ad libitum for 84 days. Different dietary fat sources had no effect on performance and/or carcass quality attributes. The soybean oil diet decreased 16:0 and 18:0 concentrations and increased 18:2 and 18:3 and the ratio of PUFA/SFA in the muscle compared with other treatments. Fish oil feeding increased 20:5 n-3 and 22:6 n-3 concentrations and decreased the ratio of n-6/n-3 in the muscle. The results demonstrate that the use of fish oil is a nutritional strategy to improve the health claimable long-chain omega-3 fatty acid content and n-6/n-3 ratio in goat meat without changing the sensory properties or colour of meat.     

Chemical composition,antioxidant activity and sensory evaluation of five different species of brown edible seaweeds

The chemical and volatile composition as well as sensory profile of five brown edible seaweeds collected in the United Kingdom, was evaluated. The ash content was 190–280 mg/g, NaCl 35.1–115.1 mg/g, protein 2.9–6.0 g/g, and fat 0.6–5.8 g/g (dry basis). Fucus vesiculosus, Fucus spiralis and Ascophyllum nodosum showed higher antioxidant activities (DPPH and FRAP). Nucleotide concentrations were of the same order of magnitude as reported in other foods such as tomatoes or potatoes, except for F. vesiculosus where levels of nucleotides were 10 times higher. The fatty acids profile was dominated by oleic acid (21.9–41.45%), followed by myristic (6.63–26.75%) and palmitic (9.23–16.91%). Glutamic and aspartic acids (0.15–1.8 mg/g and 0.05–3.1 mg/g) were the most abundant amino acids. Finally, sensory and volatile analyses illustrated that Laminaria sp. had the strongest seaweed and seafood-like aroma and taste.     

Chemical composition of beach pea (Lathyrus maritimus L.) plant parts

Samples of beach pea (Lathyrus maritimus L.) seeds and plant parts were analyzed for their chemical composition, total and free amino acids as well as minerals. The crude protein content of plant parts was from 10.7–28.0%, soluble proteins from 190–709 mg/100 g, lipid from 1.3–6.0%, ash 2.2–6.8%, crude fibre 10.7–35.5%, soluble sugars 0.1–12.2%, starch 0.8–26.5%, carbohydrate 55.8–81.5% and phenolic compounds from 0.5–3.0%. The amino acid profile of proteins of seeds and other plant parts of beach pea showed that they were deficient in sulphur-containing amino acids. Tryptophan was another limiting amino acid in plant parts, except in leaves (1.35 g/16 g N). The content of free amino acids was highest in branches plus stems (3148 mg/100 g) and lowest in pod shells (151 mg/100 g). Beach pea plant parts were a good source of minerals such as K, P, Ca, Mg, Na, Fe, Al and Zn.     

Drying kinetics of grape seeds

Drying of grape seeds representing waste products from white wine processing (Riesling), red wine processing (Cab Franc), and juice processing (Concord) was studied at 40, 50, and 60 °C and constant air velocity of 1.5 m/s. Equilibrium moisture content had a significant effect on the normalized drying curve and was determined for each grape seed at each drying temperature. Effective moisture diffusivity ranged between 1.57 and 3.96 × 10⁻¹⁰ m²/s for Riesling seeds, 2.93–5.91 × 10⁻¹⁰ m²/s for Concord seeds, and 3.89–8.03 × 10⁻¹⁰ m²/s for Cab Franc seeds. The temperature dependence of the effective diffusivity followed an Arrhenius relationship, and the activation energies were 40.14 kJ/mol for Riesling seeds, 30.45 kJ/mol for Concord seeds, and 31.47 kJ/mol for Cab Franc seeds. Three thin-layer models were used to predict the drying curves: Page model, Lewis model, and the Henderson–Pabis model. All three models were found to produce accurate predictions compared to the mass average moisture loss for each grape seed variety (percent error less than 10%), and the Lewis model was shown to be an excellent model for predicting all three grape seed varieties (percent error less than 5%).     

Amino acid composition,mineral contents and protein solubility of some lima bean (Phaseolus lunatus l. Walp) seeds coat

Seeds coat of four lima beans (Phaseolus lunatus) varieties were subjected to standard analytical techniques in order to evaluate proximate, amino acid, mineral composition and protein solubility. The proximate analysis indicates moisture content in the range of (3.17–4.96%), crude protein (14.53–15.93%), fat (0.62–0.74%), crude fibre (32.59–33.59%), ash (2.43–3.88%), and carbohydrate (47.11–48.62%) on dry weight basis. The most abundant mineral element in the studied seeds coat was potassium 361.20–459.51 mg/100 g followed by sodium 71.27–102.51 mg/100 g and magnesium 83.20–95.23 mg/100 g. Calcium, phosphorus, iron and zinc were also present in significant amount while lead, cobalt and nickel were not detected. The amino acid profile demonstrates nutritionally acceptable results for the samples due to the high levels of essential amino acids in g/100 g protein such as lysine 6.42–7.41, leucine 7.51–8.37, arginine 4.42–7.02 and phenylalanine 5.01–5.49; when compared with FAO/WHO standard; with essential amino acids (TEAA) 49.47–51.07 g/100 g protein. Glutamic and aspartic acid were the most abundant amino acid in all the samples. The protein solubility profiles showed minimum values at pH 4 and more than 70% soluble at pH 10. The study has shown the potentials of lima bean seeds coat, an agro by-products in the development of new functional ingredients for food enrichment to provide an economic alternative raw material for food industries.