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1.
Seventy six Belgian Blue (BB) bulls, with double-muscled conformation, were randomly allocated to six dietary treatments in a 2 × 3 factorial experiment. The treatments included low (N(L)=127 g CP/kg DM), medium (N(M)=153 g CP/kg DM) and high (N(H)=172 g CP/kg DM) levels of dietary protein in combination with low (E(L)=7.38 MJ ME/kg DM) and high (E(H)=8.03 MJ ME/kg DM) levels of dietary energy. Fatty acid composition was determined on total lipid samples of the M. longissimus thoracis of all animals and on the separated triacylglycerol and polar lipid fatty acid fractions of the medium-protein group. Dietary energy and protein levels influenced the carcass characteristics of BB bulls but the effects were small. Carcass fat cover score, carcass fat content and intramuscular fat content were slightly but significantly higher in the animals on the high versus the low energy diets. The overall intramuscular fat content was very low (<1%) and the overall polyunsaturated:saturated fatty acid ratio (0.39) high compared to normal figures for beef. The high versus the low dietary energy level increased the monounsaturated (P<0.001) and decreased the polyunsaturated (P<0.001) fatty acid proportion with no change in the saturated fatty acid proportion. This may have been due in part to the addition of beef tallow to increase the energy level of the diet. Concomitant shifts in the individual fatty acids included increased proportions of C14:0 (P<0.001), C16:0 (P<0.03), C16:1 (P<0.01), C18:1 (P<0.001) and decreased proportions of C18:2 (P<0.001) and C20:4 (P<0.001). Increasing dietary protein levels had inconsistent effects on the fatty acid profiles. The proportion of polar lipid fatty acids in the total fatty acids was 0.34 and 0.25 for the E(L) and E(H) group, respectively, in the Nm treatment group. Changes in fatty acid proportions of the triacylglycerol fatty acid fraction were similar to those seen in the total lipid fatty acids when related to dietary energy level, but no significant changes in the polar lipid fatty acid proportions were observed. Significant linear relationships were found between measures of carcass and muscle fatness and fatty acid proportions. With increasing muscle total fatty acid content, saturated and monounsaturated fatty acid proportions increased (r=0.38 and r=0.55, respectively, P<0.01) and the polyunsaturated fatty acid proportion decreased (r=-0.73, P<0.01). The diet had some effects but the relatively unsaturated intramuscular fatty acid composition was mainly related to the low total fat content of the BB animals.  相似文献   

2.
Palm oil (PO) and sunflower oil (SFO) blends with varying proportions were subjected to enzymatic interesterification (EIE) using a 1,3‐specific immobilised lipase. The interesterified blends were evaluated for their slip melting point (SMP), solid fat content (SFC) at 10–40 °C, p‐anisidine value, peroxide value, free fatty acids (FFA), induction period of oxidation at 110 °C (IP110) and composition of fatty acids by gas chromatography. Under EIE treatment, the blends of PO and SFO in different proportions (20:80, 40:60, 50:50, 60:40 and 80:20) had saturated and unsaturated fatty acid content in the range of 37.6–52.0% and 48.0–62.4%, respectively. The blends showed a considerable reduction in their SFC, SMP, peroxide value and oxidative stability at 110 °C, but presented increase in FFA and p‐anisidine value. The optimum condition for minimising the fatty acid in oil was obtained, at 64 °C, using 8.9% enzyme and 3 h reaction time.  相似文献   

3.
The effect of including additional oil, incorporated as whole rapeseeds, in the diet of 64 Holstein–Friesian dairy cows (32 mid‐ and 32 late‐lactation) at pasture on animal performance and milk fat composition and properties was followed over a continuous trial of 20 weeks duration. Within two stages of lactation (mid, 130 ± 16.2 days, or late, 231 ± 58.9 days), cows were allocated to concentrate treatments representing four levels of rapeseed oil inclusion, 0 (control), 200, 400 and 600 g oil day?1. Oil inclusion had little effect on milk yield but decreased milk fat content significantly (P < 0.01), with a mean depression of 0.40% at the highest level of oil inclusion. The content of milk protein also decreased with increasing addition of oil, but the decrease was smaller than the milk fat depression and was not statistically significant. Increasing the level of rapeseed oil in the diet to 600 g oil day?1 resulted in linear changes in milk fat and protein concentrations which were described by regression equations. For each 100 g of rapeseed oil added to the diet, milk fat content decreased by 0.068% in mid‐lactation cows and 0.061% in late‐lactation cows, while protein content decreased by 0.026% in mid‐lactation cows and 0.028% in late‐lactation cows. Total unsaturated fatty acid content of milk fat also increased in a linear fashion with increased level of oil addition, from 345.7 g kg?1 total fatty acids in control milk fat to 459.3 g kg?1 total fatty acids at 600 g oil day?1, while total saturated fatty acids decreased in the same milk fats from 640.7 to 522.2 g kg?1 total fatty acids. These changes were reflected in lower solid fat contents (SFC) in the milk fat at the lower temperatures of measurement, eg 41% SFC at 5 °C at the highest level of oil inclusion compared with 52% in the control milk fat. However, SFC at 20 °C showed little difference with increasing level of dietary oil addition, an important factor in maintaining product integrity at room temperatures. The relatively high content of the monounsaturated fatty acid C18:1 (345.5 g kg?1 total fatty acids at 600 g oil day?1) and low content of polyunsaturated fatty acids (total C18:2 and C18:3 <40 g kg?1 total fatty acids at 600 g oil day?1) ensured that the oxidative stability of the treatment and control milk fats did not differ significantly. Stage of lactation had an unexplained effect of consistent magnitude on milk fat composition throughout the trial period, with late‐lactation animals producing milk fats containing a significantly (P < 0.001) higher proportion of unsaturated fatty acids than the mid‐lactation animals. Changes in the proportions of unsaturated fatty acids in milk fat, as reflected by changes in iodine value, were established within 2 weeks of the trial commencing and persisted over the 20 weeks of the trial duration. No adverse effect on animal health from this type of dietary manipulation was identified. Copyright © 2004 Society of Chemical Industry  相似文献   

4.
Fat blends, formulated by mixing refined, bleached and deodorised (RBD) palm oil (PO) or RBD palm stearin (PS) with RBD rice bran oil (RBO) in various ratios were subjected to chemical interesterification (CIE) at pilot scale using sodium methoxide (NaOMe) as catalyst. The resultant interesterified fat was processed through a margarine crystalliser under optimised conditions. The blends before and after CIE were investigated for triacylglycerol (TAG) composition, solid fat content (SFC) and melting characteristics, polymorphic form, fatty acid composition (FAC), bioactive (tocols, sterols, oryzanol) constituents and trans fatty acids (TFA). CIE was found to be very effective in terms of rearrangement of fatty acids (FAs) among TAGs and consequent changes in the physical characteristics. The SFC of the interesterified PS/RBO blends decreased significantly ( P  ≤ 0.05) when compared with those of PO/RBO blends. The interesterified binary blends with 50–60% PS and 40–50% RBO, and 70–80% PO and 20–30% RBO had SFC curves in the range of all-purpose type shortenings. CIE facilitated the formation of β' polymorphic forms. FAC of shortenings prepared using the optimised blends contained 15–20% C18:2 polyunsaturated fatty acid (PUFA) and no TFA. Total tocol, sterol and oryzanol content of zero trans shortenings were 650–1145, 408–17 583 and 1309–14 430 ppm. CIE using NaOMe did not affect the bioactive constituents significantly ( P  ≤ 0.05).  相似文献   

5.
Biotin (D-biotin) was supplemented to F1 Wagyu/Black Angus steers fed a wheat-based ration to evaluate the effect on meat quality. One hundred and eight steers of known Wagyu sire lines were assigned to three biotin treatments (0, 10 and 20mg/head/day) with each treatment replicated four times using an unfasted liveweight of 410.5kg (±24.42 SD). Biotin supplementation had no effect (P>0.05) on beef marbling standard at either the 5/6th or 10/11th rib quartering site, 10/11th rib intra-muscular fat percentage, intra-muscular fat fatty acid composition or adipose melting points. Wagyu genotype had an effect (P<0.05) on beef marbling standard and intra-muscular fat percentage at the 10/11th rib, inter-muscular and intra-muscular melting point and fatty acid composition of intra-muscular fat. A significant (P<0.001) but poor correlation existed between beef marbling standard and intra-muscular fat percentage (R(2)=0.198). Total conjugated linoleic acid had a highly significantly (P<0.0001) positive correlation to intra-muscular fat percentage (R(2)=0.446).  相似文献   

6.
SUMMARY– Analysis was made of the fatty acid composition of liver, adipose fat, thigh and breast muscles of broilers fed corn-soy commercial-type of diets containing one of two levels of fish oil (2.5 or 5.0%). The oil was subsequently continued, withdrawn or replaced with yellow grease 2, 3 or 4 weeks before termination of the experiment at the 8th week. The tissue contents of four w-3-type fatty acids (20:4, 20:5, 22:5 and 22:6) were increased in relation to the number of weeks menhaden fish oil was included in the diet. (The first number indicates the chain length of carbons, the second indicates the number of double bonds. The number following w (omega) indicates the carbon position of the first double bond as counted from the terminal methyl group.)
Of the four tissues studied, the liver had the highest total content of the w 3 fatty acids; the adipose fat, the least. The muscles had intermediate values; the breast containing more than the thigh. Withdrawal of fish oil at the 4th week resulted in favorable organoleptic evaluation. A more favorable evaluation was obtained if yellow grease was substituted in place of fish oil for the last 4 weeks. The organoleptic scores were highly significantly correlated with the content of 20:5 03, 22:5 w 3 and 22:6 w 3 but it was less significantly correlated with the content of 20:4 w 3. An inverse relation existed between the content of the w 3 with that of the w 6 fatty acids.  相似文献   

7.
Today’s consumers look for foods which provide nutrition and pleasure, while safeguarding their health, the result of which is that they increasingly avoid foods containing cholesterol and saturated and trans fatty acids. Chemically modified vegetable oils can help tailor meat products to meet this growing need and at the same time fulfil the technological needs of the meat processing industry. In this study, 16 backfat samples were characterised for their solid fat content (SFC) and melting point and these characteristics were used to design a mixture of chemically modified vegetable oils for use as a pork fat substitute for elaborating sausages. The mixtures were prepared with different vegetable oils bearing in mind with stearic acid content due to its close correlation with the SFC. The backfat was characterised as a function of its SFC and some modified vegetable oil mixtures were proposed, which led to a 10–20% diminution in saturated fatty acids and with a melting point similar to those observed in the backfat. The fatty acid profile pointed to a polyunsaturated/saturated fatty acids ratio higher than 0.4, and an n − 6/n − 3 fatty acid ratio of less than 4 in both modified vegetable oil mixtures proposed.  相似文献   

8.
通过对蒙古斑点马不同部位脂肪和肌肉组织中脂肪酸组成进行分析比较,旨在明确蒙古斑点马体脂脂肪酸组成特点。选择3 匹成年蒙古斑点马,屠宰后采集肾周、肠周和皮下脂肪以及肩肌、背最长肌和臀肌样品,利用气相色谱法测定脂肪酸组成及含量。结果表明:蒙古斑点马不同脂肪组织中均检出19 种脂肪酸,其中饱和脂肪酸(saturated fatty acid,SFA)含量34.77%~37.38%,不饱和脂肪酸(unsaturated fatty acid,UFA)含量达60%以上,UFA中单不饱和脂肪酸(monounsaturated fatty acid,MUFA)含量33.04%~36.39%,多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)含量26.47%~27.51%,其中皮下脂肪C10:0、C18:0、C20:0含量显著低于肾周和肠周脂肪(P<0.05);MUFA在皮下脂肪的沉积程度较其他2 个部位高,但均无统计学差异;PUFA中C18:3 n-3含量最高,其在各脂肪组织间无显著差异。3 个不同部位肌肉中均检出15 种脂肪酸,其中SFA含量占总脂肪酸含量的38.32%~40.04%,MUFA含量占35.70%~40.19%,PUFA含量占15.25%~20.33%;SFA中背最长肌和臀肌C12:0含量显著高于肩肌(P<0.05),其余SFA在不同部位肌肉间无显著差异;MUFA中背最长肌C16:1含量显著高于肩肌和臀肌(P<0.05);肩肌n-6/n-3 PUFA比值显著高于背最长肌和臀肌(P<0.05);皮下脂肪的C18:3 n-3和总PUFA含量显著高于背最长肌(P<0.05)。综上所述,蒙古斑点马不同部位脂肪和肌肉组织脂肪酸组成各具特点,但UFA含量均较高。  相似文献   

9.
Lambs were fed ad libitum on a diet containing the β-adrenergic agonist salbutamol (2 ppm) for 38 days to investigate its effects on organ weights, muscle composition and fatty acid profiles. The influence of a 5-day withdrawal period was also assessed. The oral administration of salbutamol did not increase muscle weights and no differences were found in liver, heart and lung proportions. However, kidney weight was higher in the salbutamol-not-withdrawn animals. In treated animals fat and collagen levels decreased (P < 0.05), while protein increased (P < 0.05) in the semitendinosus (ST) muscle when compared to controls. However, no effects of the β-agonist treatment were found in the longissimus dorsi (LD) muscle. Intramuscular LD polyunsaturated fatty acids were higher (P < 0.05). Subcutaneous adipose tissue samples were higher (P < 0.05) in total unsaturated fatty acids and lower (P < 0.05) in total saturated fatty acids. All these changes in the fatty acid profiles of both intramuscular and adipose tissues were more marked after the 5-day salbutamol withdrawal period.  相似文献   

10.
Thirty-six castrated male growing pigs were used to study the effect of dietary beef tallow (BT) versus sunflower oil (SO) on meat quality and fatty acid composition of various tissues. The diets used contained either 5% (w/w) of the variable fat source. The fat type had no significant effect on carcass traits (carcass weight, back-fat thickness, fat-lean ratio) and meat quality (colour, pH(1), pH(U), drip losses, cooking losses, shear force, sacromere length, loin moisture, loin marbling). The diet with SO instead of BT significantly increased the incorporation of polyunsaturated fatty acids in adipose tissues, loin and liver at the expense of the sum of saturated and monounsaturated fatty acids. In erythrocytes, the diet containing SO raised the contents of saturated and polyunsaturated fatty acids and lowered that of monounsaturated fatty acids. In particular, the SO diet produced an increase in the content of linoleic acid (C18:2n-6) in the various tissues. It is concluded that feeding a diet with SO instead of BT altered the fatty acid composition of tissues without simultaneously affecting various characteristics of meat quality.  相似文献   

11.
Fatty acids in samples (n=74) of pork adipose tissue were measured with a Fourier transform mid-infrared (FT-MIR) spectrometer and by gas chromatography. The measured absorption spectra provided information to estimate partial least squares regression models for fatty acid groups, the iodine value and several fatty acids. The iodine values were predicted with correlation coefficient R=0.996 and root mean square error of cross-validation RMSECV=0.658. The sum of the two marine fatty acids of main interest, C22:5n3+C22:6n3, were predicted with R=0.982 and RMSECV=0.062. The K nearest neighbours procedure successfully classified the samples in three classes, depending on their proportions of marine fatty acids. Application of fat and absorption measurements were rapid, requiring less than 5 min of labour per sample. The results reported in this paper demonstrate that FT-MIR measurements can serve as a rapid method to determine marine fatty acids in pork fat.  相似文献   

12.
Eighty eight lambs were used in a 2 × 2 factorial arrangement 1) to investigate the effect of maternal dietary linseed supplementation and/or lamb linseed supplemented concentrate on growth performance, carcass fat quality and fatty acid (FA) composition of muscle and dorsal adipose tissue of indoor lambs 2) to study the relationships between subcutaneous fat quality and FA composition. Feeding linseed to ewes increased C18:3 n-3 (ALA) proportion in milk and therefore the ALA supply to suckling lambs. However, ALA and n-3 polyunsaturated FA (n-3 PUFA) proportions in lamb tissues were not affected. Feeding linseed to lambs during the post-weaning period significantly increased the proportions of ALA and n-3 PUFA in tissues. Softer and more colored fat was associated with a decrease in even medium-chain saturated FA and increases in odd and methyl FA proportions but not with ALA proportion in subcutaneous adipose tissue.  相似文献   

13.
Our objective was to examine effects of exogenous bovine somatotropin (bST), pregnancy, and dietary fatty acids on fatty acid distribution in various tissues of lactating dairy cows. Two diets were fed, starting about 17 d in milk (DIM), in which oil of whole cottonseed (control diet) was compared with a calcium salt of fish oil-enriched lipid (FO; 1.9% of dietary DM). Starting at 44 ± 5 DIM, ovulation was synchronized with a presynchronization plus Ovsynch protocol (d 0 = time of synchronized ovulation). Some cows were inseminated (77 ± 12 DIM) to create a pregnant group. On d 0 and 11, cows received bST (500 mg) or no bST, and were killed on d 17 (94 ± 12 DIM). Number of cows in control group was 5 bST-treated cyclic (bST-C), 5 non-bST-treated cyclic (no bST-C), 4 bST-treated pregnant (bST-P), and 5 non-bST-treated pregnant (no bST-P) cows; and for the FO diet: 4 bST-treated (bST-FO-C) and 5 non-bST-treated cyclic (no bST-FO-C) cows. At slaughter, samples of endometrium, liver, muscle, s.c. adipose, internal adipose, and mammary gland were collected. Milk was collected at 75 ± 5 DIM. Gas chromatography was used to determine fatty acid percentages in tissues and milk fat. Endometrium from the cows fed FO had increased proportions of C20:5 and C22:6, whereas C20:4 was decreased. Injections of bST reduced both C18:2 and the n-6:n-3 ratio, but increased C22:6 in endometrium of cyclic control-fed, but not pregnant cows. In addition, FO decreased the n-6:n-3 ratio in all tissues and milk fat except for s.c. and internal adipose tissue. Cows fed FO also had increased C18:3, C20:5, and C22:6 in the liver and mammary tissue, and C18:3 and C22:6 were increased in the milk fat. The FO diet decreased the Δ9-desaturase index [(product of Δ9-desaturase]/(product of Δ9-desaturase + substrate of Δ9-desaturase]; DIX) in muscle and s.c. tissues, accompanied by an increase in saturated fatty acid (SFA) percentage. In addition, FO diet decreased DIX in the endometrium. In mammary and internal adipose tissues, bST increased DIX in cyclic control-fed cows, whereas bST decreased DIX in FO-fed cows, with no difference in the concentration of SFA and UNSFA. Cis-9, trans-11 conjugated linoleic acid was increased in milk fat, but decreased in the muscle and s.c. adipose tissue of FO-fed cows. The FO-enriched lipid, bST treatment, and early pregnancy can alter fatty acid percentages and distributions that may alter tissue functionality and functional nutrients of consumer products.  相似文献   

14.
Over the past few decades, consumption of butter has declined due to its high content of saturated fatty acids and cholesterol. Opposingly, phytosterol esters (PE) have been used as a food ingredient for their effectiveness in lowering plasma cholesterol levels. The objective of this work was to evaluate the effects of the addition of PE on the physical and chemical properties of milkfat (MF). The fatty acid and sterol compositions were determined by gas chromatography (GC). A constant speed texture analyser was used to evaluate consistency. Solid fat content (SFC) was determined by nuclear magnetic resonance (NMR) and crystal structure was observed with polarized light microscopy. Results showed that β-sitosterol (33.5%), campesterol (23.6%), and stigmasterol (14.9%) were the most abundant sterols in the PE blend. Blends containing MF and PE presented a softer consistency than pure MF at low temperatures. Despite the higher SFC, PE caused a decrease in the SFC of MF. The images of MF, PE, and their blends obtained by polarized light microscopy showed the influence of temperature on crystal size and number. This method revealed the particular crystalline structure of PE, formed by a solid, dense crystal network, with amorphous crystals of varied sizes, different from crystal structures generally observed in fats. The high SFC and low consistency of PE may indicate a weak crystal network, probably due to the presence of different molecular structures.  相似文献   

15.
Fractionation of milk fat by short-path distillation   总被引:5,自引:0,他引:5  
Fractionation of milk fat by short-path distillation changes the chemical composition and physical properties of the resulting fractions. Increases in distillation temperature from 125 to 250 degrees C increased distillate yield from 0.3 to 42.7% (wt/wt). The distillate was enriched in short- and medium-chain fatty acids and low molecular weight acylglycerols, while the retentate was enriched in long-chain saturated and unsaturated fatty acids as well as high molecular weight acylglyerols. As distillation temperature increased, dropping points of the distillate increased. Relative to native milk fat, the solid fat content (SFC) vs. temperature melting profile of the distillate was depressed and that of the retentate was augmented, which correlated with the saturated long-chain fatty acid content in the fractions. Retentate crystallization parameters obtained by fitting the Avrami model to SFC-time data, did not change as a function of distillation temperature, but varied as a function of the degree of undercooling. Changes in microstructure observed by polarized light microscopy also appeared to be solely a function of the degree of undercooling, with no observable differences between retentates obtained at the different distillation temperatures. In addition, no changes in the retentate's free energy of nucleation (deltaGc) as a function of distillation temperature were found. The compressive storage modulus of the crystallized retentate increased as a function of increasing distillation temperature.  相似文献   

16.
Sixteen steers (441±31.7kg initial body weight) consumed two high concentrate diets with either 0 or 3% fish oil to determine the impact of fish oil, an omega-3 fatty acid source, on the fatty acid composition of beef carcasses. Collected tissue samples included the Longissimus thoracis from the 6th to 7th rib section, ground 10th to 12th rib, liver, subcutaneous adipose tissue adjacent to the 12th rib, intramuscular adipose tissue in the 6th to 7th rib sections, perirenal adipose tissue, and brisket adipose tissue. Including fish oil in the diet increased most of the saturated fatty acids (P<0.01) and proportions of polyunsaturated fatty acids (P<0.06), and decreased (P<0.01) proportions of monounsaturated fatty acids. Dietary fish oil increased (P<0.01) levels of omega-3 fatty acids in sampled tissues, resulting in lower (P<0.01) omega-6:omega-3 ratios. The weight percentages of C20:5 and C22:6 in tissue may provide the recommended daily allowance for humans. Fish oil may have a role in beef niche marketing if there are no deleterious effects on consumer satisfaction.  相似文献   

17.
Tang L  Hu JN  Zhu XM  Luo LP  Lei L  Deng ZY  Lee KT 《Journal of food science》2012,77(4):C454-C460
It is known that Cinnamomum camphora seed oil (CCSO) is rich in medium-chain fatty acids (MCFAs) or medium-chain triacylglycerols (MCTs). The purpose of the present study was to produce zero-trans MCTs-enriched plastic fat from a lipid mixture (500 g) of palm stearin (PS) and CCSO at 3 weight ratios (PS:CCSO 60:40, 70:30, 80:20, wt/wt) by using lipase (Lipozyme TL IM, 10% of total substrate) as a catalyst at 65 °C for 8 h. The major fatty acids of the products were palmitic acid (C16:0, 42.68% to 53.42%), oleic acid (C18:1, 22.41% to 23.46%), and MCFAs (8.67% to 18.73%). Alpha-tocopherol (0.48 to 2.51 mg/100 g), γ-tocopherol (1.70 to 3.88 mg/100 g), and δ-tocopherol (2.08 to 3.95 mg/100 g) were detected in the interesterified products. The physical properties including solid fat content (SFC), slip melting point (SMP), and crystal polymorphism of the products were evaluated for possible application in shortening or margarine. Results showed that the SFCs of interesterified products at 25 °C were 9% (60:40, PS:CCSO), 18.50% (70:30, PS:CCSO), and 29.2% (80:20, PS:CCSO), respectively. The β' crystal form was found in most of the interesterified products. Furthermore, no trans fatty acids were detected in the products. Such zero-trans MCT-enriched fats may have a potential functionality for shortenings and margarines which may become a new type of nutritional plastic fat for daily diet.  相似文献   

18.
Bambangan (Mangifera pajang) is one of the underutilised tropical fruits found in the Borneo islands (Malaysia, Indonesia and Brunei). The physicochemical and thermal properties of bambangan kernel fat (BKF) were investigated in an effort to identify an innovative fat that could be exploited in confectionery applications. The fatty acids and triglyceride (TG) contents, melting behaviour and solid fat content (SFC) of the BKF were determined by various chromatographic and thermal techniques. BKF had three main TGs, namely 1‐palmitoyl‐2‐oleoyl‐3‐stearoyl‐glycerol (POS) (11.6%), 1,3‐distearoyl‐2‐oleoyl‐glycerol (SOS) (28.7%) and 1‐stearoyl‐2,3‐dioleoyl‐glycerol (SOO) (11.2%), with SOS being the major component. Stearic, oleic and palmitic acids were the dominant fatty acids with the area percentage of 36.4%, 44.5% and 8.4%, respectively. The melting behaviour indicated a single curve with only one maximum shoulder. With respect to the physicochemical and thermal properties, BKF is ideal for use in formulations (blending components) as an alternative to CB in food products, especially confectionary products.  相似文献   

19.
Abstract: Omega‐3 fatty acids (n‐3 FAs) have been positively associated with prevention and treatment of chronic diseases. Intake of high amounts of trans fatty acids (TFAs) is correlated with increased risk of coronary heart disease, inflammation, and cancer. Structured lipid (SL) was synthesized using stearidonic acid (SDA) soybean oil and high‐stearate soybean oil catalyzed by Lipozyme® TLIM lipase. The SL was compared to extracted fat (EF) from a commercial brand for FA profile, sn‐2 positional FAs, triacylglycerol (TAG) profile, polymorphism, thermal behavior, oxidative stability, and solid fat content (SFC). Both SL and EF had similar saturated FA (about 31 mol%) and unsaturated FA (about 68 mol%), but SL had a much lower n‐6/n‐3 ratio (1.1) than EF (5.8). SL had 10.5 mol% SDA. After short‐path distillation, a loss of 53.9% was observed in the total tocopherol content of SL. The tocopherols were lost as free tocopherols. SL and EF had similar melting profile, β’ polymorph, and oxidative stability. Margarine was formulated using SL (SLM) and EF (RCM, reformulated commercial margarine). No sensory difference was observed between the 2 margarines. The SL synthesized in this study contained no TFA and possessed desirable polymorphism, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL was trans‐free and SDA‐enriched. Practical Application: The current research increases the food applications of stearidonic acid (SDA) soybean oil. trans‐Free SDA containing SL was synthesized with desirable polymorph, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL had no trans fat and had a low n‐6/n‐3 ratio. This may help in reducing trans fat intake in our diet while increasing n‐3 FA intake.  相似文献   

20.
NIRS potential to estimate the proportion of PUFA and their biohydrogenation products in adipose tissues from cattle fed sunflower or flaxseed was tested. Immediately after skinning, perirenal and subcutaneous fat samples from 63 steers were collected, scanned intact at 37 °C and 33 °C, respectively, over a NIR spectral range from 400 to 2498 nm using benchtop equipment and then analyzed for fatty acid composition. NIRS calibrations in perirenal fat showed high predictability for total and major omega − 6 and omega − 3, conjugated linolenic acids, t,t-conjugated linoleic acids (CLA), non-CLA dienes and trans-monounsaturated fatty acids, with R2 (RMSECV, %) of 0.88–0.89 (0.16–0.20), 0.89–0.91 (0.07–0.08), 0.86–0.89 (0.01–0.09), 0.82 (0.07), 0.89 (0.46) and 0.86–0.88 (0.87–1.29), respectively. NIRS predictions in subcutaneous fat were less reliable, probably due to lower fatty acid variability. The results show NIRS to be a useful technique for the early, fast and relatively inexpensive estimation of proportions of fatty acids with potential human health effects in cattle perirenal fat.  相似文献   

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