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1.
The peach palm (Bactris gasipaes Kunth) is the starchy fruit of a palm tree widely cultivated in Central and South America. The present study aimed at determining its chemical composition and its nutritive value in rats. The average chemical composition of 17 samples was as follows: 410 g kg?1 water and, in g kg?1 of dry matter (DM), 54 g crude protein, 114 g oil, 39 g neutral detergent fibre, 716 g starch, 21 g sugars and 18 g ash. The main variability was observed for the oil (60–180 g kg?1 DM) and starch (590–780 g DM) contents. The proteins contained, on average, in g kg?1 of proteins, 49 g lysine, 13 g methionine, 19 g cysteine, 39 g threonine and 7 g tryptophan. The mineral fraction contained, per kg DM: 1.0 g Ca, 0.8 g P, 0.6 g Mg, 0.3 g Na, 44 mg Fe, 4 mg Cu and 10 mg Zn. The digestibility of four peach palm genotypes was determined in rats fed a diet composed of 350 g kg?1 of peach palm and 650 g of a control diet based on maize and soybean meal. The digestibility of DM, energy, starch and protein of peach palm alone reached, on average 91, 87, 96 and 95%, respectively. No difference was observed between varieties, except for starch (p < 0.05). On average, peach palm contained 51 g of truly digestible protein kg?1 DM and 3.691 kcal digestible energy kg?1 DM. A growth trial was also carried out for 1 month on rats (initial weight: 78 g) fed a diet containing 0, 200, 400, 600 or 800 g peach palm kg?1, at the expense of a diet composed of maize starch and casein. The growth rate of the rats decreased (p < 0.05) as the peach palm concentration increased. The growth decrease was due to a decrease (p < 0.05) in DM intake and to the lower quality of the peach palm protein. It is concluded that peach palm is mainly an energy source for humans and animals. It is poor in protein and minerals but can be consumed in large amounts. Copyright © 2005 Society of Chemical Industry  相似文献   

2.
Four antibiotics, namely procaine penicillin, tylosin, streptomycin and neomycin-oxytetracycline each at 150 mg · kg?1, and four levels of dried yeast, viz. 1.5, 3.0, 4.5 and 6.5 g · kg?1 were incorporated into a basal high fibre diet containing 250 g · kg?1 palm kernel meal. The unsupplemented diet was the control. The nine experimental diets were fed to broilers between 7 and 42 days of age to evaluate performance, carcass characteristics, organ weights and haematology in response to the supplements. The investigation revealed that broilers fed antibiotics or dried yeast supplemented diets attained heavier (P < 0.05) body weights, consumed greater (P < 0.05) quantities of feed except on penicillin and 6.0 g · kg?1 dried yeast, converted the feed better (P < 0.05), and yielded heavier carcass and cut-parts than those fed the unsupplemented diet. Organ weights were similar in broilers on the treatments, except the greater (P < 0.05) hepatic, spleenic and gizzard weights and lengthier intestinal tracts in birds fed dried yeast. Haematological indices were superior (P < 0.05) in broilers fed supplemented diets to the basal group. The data suggest improvement in performance, carcass yield and haematology of broilers as a result of antibiotics or dried yeast supplementation of a high fibre diet.  相似文献   

3.
Twenty-four, 13–14 week pregnant Cheviot ewes were offered either a basal grass cube diet containing 0.3 mg cadmium (Cd) kg?1, or the same diet supplemented with Cd to give dietary Cd contents of 3.4 or 6.4 mg Cd kg?1. Increasing dietary Cd had no effect on numbers of viable offspring or mean birth weight of lambs. After weaning, some of the lambs were maintained on the same diets as their respective dams for approximately 280 days. Increased dietary Cd had no effect on food intake or carcass weight at slaughter. The liver zinc content of lambs consuming the diet with the highest Cd content declined significantly. Increasing the dietary content of Cd decreased the retention of copper by the liver. At slaughter, Cd could not be detected in blood nor in muscle tissues selected to represent prime cuts of edible carcass meat. In contrast, increased dietary Cd resulted in significantly elevated liver and kidney Cd contents.  相似文献   

4.
Pigmeat products have been associated with an unhealthy image due to the relative proportions of polyunsaturated and saturated fatty acids. The aim of this experiment was to improve the fatty acid profile of the carcass fat by feeding various dietary sources of fat. Groups of 10 female Large While × Landrace pigs were fed one of four experimental diets. Five in each group were slaughtered at 70 kg live weight and the remaining five at 100 kg live weight. The diets were offered ad libitum and daily intake was recorded. The diets were based on barley, soya bean meal and fishmeal. Diet 1 contained 50 g tallow kg?1, a relatively saturated fat, and diets 2, 3 and 4 contained 50 g soya oil kg?1, an unsaturated fat. Diet 3 also contained 7.5 g GLA oil kg?1, which is rich in gamma linolenic acid, with the aim of increasing the production of arachidonic acid in the body fat. Diet 4 was supplemented with 9.5 g EPAnoil kg?1, which is rich in eicosapentaenoic acid and docosahexaenoic acid. There were no significant differences between dietary treatments in performance (daily liveweight gain or the efficiency of food conversion to liveweight gain) of the pigs slaughtered at 70 kg live weight, but small differences were observed at 100 kg live weight, where pigs on treatments 2, 3 and 4 performed slightly better than those on treatment 1. At both slaughter weights the lipid content of the m semitendinosus was higher than that of the m longissimus dorsi (approximately 24 and 13 g kg?1, respectively). The pattern of fatty acids in the dietary fat was reflected to varying degrees in the carcass fat. Diet 1 resulted in the highest levels of palmitic, palmitoleic, stearic and oleic acids whereas diets 2, 3 and 4 gave high levels of linoleic and linolenic acids. The extra gamma linolenic acid in diet 3 did not result in a consistently significant increase in the production of arachidonic acid. The supplement of EPAnoil gave significant increases in the levels of eicosapentaenoic and docosahexaenoic acids in the body lipids. The polyunsaturated to saturated fatty acid ratio of the body lipid was increased with diets 2, 3 and 4 to about 1.0. In spite of high levels of linoleic acid, there were no adverse effects during the processing of the carcasses and the taste panel evaluation did not reveal any treatment differences.  相似文献   

5.
Seven duplicate floor pens with 20 day-old commercial broiler chicks each were fed a practical type broiler diet formulated with guineacorn/palm kernel meal and supplemented with graded levels of biotin (0.00, 0.04, 0.08, 0.12, 0.16, 0.20 and 0.24 mg kg?1 feed) for a period of 6 weeks. Significantly poorer feed utilisation and carcass characteristics, higher blood lipid, lower blood glucose, lower pyruvate carboxylase activity in the liver, higher liver and kidney weights (% live weight), more lipid deposition in these organs coupled with more frequent incidences of foot dermatitis, higher mortality due to fatty liver and kidney syndrome (FLKS) and abnormal development of leg bone in broilers maintained on the diet without biotin supplementation indicated that they suffered vitamin deficiency. However, the responses of experimental birds indicated that a dietary supplement of 0.20 mg biotin kg?1 feed was adequate for the promotion of good performance and prevention of dermal lesions, FLKS mortality and leg deformities.  相似文献   

6.
Twenty‐four Large White × Landrace pigs were individually fed, from 50 to 90 kg live weight, either a control (CONT) diet containing palm oil or one of three diets based on full‐fat rapeseed (250 g kg−1) (diets RD). The RD diets were supplemented with 0, 200 or 500 mg DL ‐α‐tocopherol acetate (ATA) kg−1 diet (diets RD0, RD200 and RD500 respectively). Diets were formulated to be isonitrogenous and isocaloric. Daily live weight gain was significantly increased (p < 0.01) in pigs fed diet RD500. Plasma AT concentration was significantly increased by dietary supplementation with 200 mg ATA kg−1 but showed no further significant increase by supplementation with 500 mg ATA kg−1. At slaughter, after 45 days, carcass weights were increased for the RD500 group but dressing percentage was unaffected. ATA supplementation significantly reduced drip loss on days 4 and 5–7 in fresh muscle and on days 1 and 4 in frozen muscle. The concentrations of calcium, sodium and potassium in drip loss fluid collected on days 1 and 4 from fresh muscle were not significantly affected by treatment or by time of collection and did not suggest any change in the relative contribution of intra‐ and extracellular fluid to total drip loss. Plasma enzyme activities related to tissue damage (creatine kinase, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase) were not influenced by dietary treatments. © 2000 Society of Chemical Industry  相似文献   

7.
A study was conducted to determine the effects of graded levels of dietary inclusion of a cysteamine (Cs) preparation on growth performance, carcass quality, plasma hormone levels, gastric pH and occurrence of gastric ulcer in finishing pigs. A total of 384 Landrace × Large White finishing pigs, (192 gilts and 192 barrows) with an average initial body weight of 66.05 ± 0.623 kg (mean ± SEM) were randomly divided into 24 floor pens, with eight gilts and eight barrows in each pen (9.2 m2) as one experimental unit. The 24 pens of pigs were randomly allocated to one of three diets: (1) a maize/soybean meal basal diet; (2) the basal diet plus 30 mg Cs kg?1 diet; and (3) the basal diet plus 50 mg Cs kg?1 diet. Dietary supplementation of Cs had quadratic effects (P < 0.01) on final body weight and average daily gain, with optimal responses occurring at 30 mg kg?1. Dietary supplementation of Cs quadratically improved (P < 0.01) average daily feed intake and feed/gain ratio, with optimal responses occurring at 30 mg kg?1. Dietary supplementation of Cs had a quadratic effect (P < 0.01) on muscle RNA/DNA ratio. Furthermore, dietary supplementation of Cs reduced (P < 0.05) back‐fat thickness. Dietary supplementation of Cs had quadratic effects (P < 0.05) on plasma glucagon and T3 hormone levels, with optimal responses occurring at 30 mg kg?1, but had no effect (P > 0.05) on plasma growth hormone, insulin and T4 levels. There were no apparent pathological changes seen in the stomach mucosa of pigs fed at 30 mg Cs kg?1 compared with the control diet. It is concluded that a low dose of dietary inclusion of Cs at 30 mg kg?1 can improve growth performance and carcass quality without adverse effects on the stomach in finishing pigs. Copyright © 2005 Society of Chemical Industry  相似文献   

8.
BACKGROUND: Bioactive compounds are capable of providing health benefits, reducing disease incidence or favoring body functioning. There is a growing search for vegetable oils containing such compounds. This study aimed to characterize the pulp and kernel oils of the Brazilian palm species guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana) and macaúba (Acrocomia aculeata), aiming at possible uses in several industries. RESULTS: Fatty acid composition, phenolic and carotenoid contents, tocopherol composition were evaluated. The majority of the fatty acids in pulps were oleic and linoleic; macaúba pulp contained 526 g kg?1 of oleic acid. Lauric acid was detected in the kernels of all three species as the major saturated fatty acid, in amounts ranging from 325.8 to 424.3 g kg?1. The jerivá pulp contained carotenoids and tocopherols on average of 1219 µg g?1 and 323.50 mg kg?1, respectively. CONCLUSION: The pulps contained more unsaturated fatty acids than the kernels, mainly oleic and linoleic. Moreover, the pulps showed higher carotenoid and tocopherol contents. The kernels showed a predominance of saturated fatty acids, especially lauric acid. The fatty acid profiles of the kernels suggest that these oils may be better suited for the cosmetic and pharmaceutical industries than for use in foods. Copyright © 2011 Society of Chemical Industry  相似文献   

9.
The present study was conducted to evaluate the effect of feed‐grade enzyme supplementation in diets with varying levels of energy on the performance of growing and laying Japanese quails. Day‐old Japanese quails, 504 in number, were subjected to six dietary treatments with six replicates at each treatment. Each replicate had 14 chicks. The dietary treatments consisted of three energy levels ie 12.15 MJ (2900 kcal), 11.30 MJ (2700 kcal) and 10.48 MJ (2500 kcal) ME kg?1 diet and two enzyme levels (0 and 0.5 g kg?1 diet). A metabolism trial was conducted at the fourth week of age. At the end of week 5, 10 quails (five of each sex) per treatment were sacrificed for carcass characteristics and 20 female quails from each of the six dietary groups were housed in individual laying cages and fed respective layer diet to study the laying performance and egg quality up to 20 weeks of age. Body weight gains of quails fed 12.15 MJ or 11.30 MJ ME kg?1 diets were significantly higher (p < 0.01) than those fed diets with 10.46 MJ ME kg?1 diet. Feed intake was significantly lower (p < 0.01) in birds that received diet with 12.15 MJ ME kg?1 than in birds that diets containing either 11.30 or 10.46 MJ ME kg?1 diet. Feed conversion ratio (p < 0.01) was best at 12.15, followed by 11.30 and 10.46 MJ ME kg?1 diet. Enzyme supplementation did not improve the growth performance, feed intake or feed conversion efficiency of quails. Enzyme addition also did not influence nitrogen retention or energy or dry matter metabolizability. The carcass characteristics did not differ because of energy or enzyme supplementation. Feed intake increased significantly (p < 0.01) as the dietary energy level decreased. The egg production and quality characteristics remained almost similar in all the dietary treatments. It was concluded that the optimum dietary energy level for quail was 12.15 MJ (2900 kcal) ME kg?1 during the growing phase and 11.30 MJ (2700 kcal) ME kg?1 during the laying phase. Addition of feed enzymes to conventional diets containing varying levels of maize, soyabean meal, fish meal and deoiled rice bran was not beneficial to improve growth, carcass traits, egg production performance or nutrient utilization. Copyright © 2004 Society of Chemical Industry  相似文献   

10.
An efficient pilot‐scale process was developed to produce nutraceutical products from fresh sea buckthorn (Hippophae rhamnoides) berries. Fresh berries were subjected to high‐pressure dewatering using a continuous screw press. The separated liquid phase containing 80–90% of pulp oil was clarified at 80 °C and centrifuged to obtain pulp oil, clear juice and sludge. The pulp oil yield was 2.7–2.8% of fresh berry weight with 66–70% extraction efficiency. The pulp oil was remarkably rich in carotenoids (2450–2810 mg kg?1), tocopherols (1409–1599 mg kg?1) and sterols (4096–4403 mg kg?1), with a characteristic fresh berry flavour and 16:1 as the major fatty acid (45.6–49.1%). The clear juice obtained was free from oil and contained high amounts of vitamin C (1683–1840 mg kg?1) and phytochemicals such as polyphenols (2392–2821 mg kg?1) and flavonoids (340–401 mg kg?1). Isorhamnetin (251–310 mg kg?1) was the major flavonoid in the juice, along with quercetin (77–81 mg kg?1) and kaempherol (12–16 mg kg?1). The juice was very acidic (pH 3), with high concentrations of organic acids (30.8–36.0 g kg?1). High‐performance liquid chromatography profiling of organic acids revealed quinic acid (18.1–19.9 g kg?1) as the major acid in the juice. The seeds in the pressed cake were separated and extracted for oil using supercritical CO2. Copyright © 2006 Society of Chemical Industry  相似文献   

11.
New Zealand White rabbits, aged between 5 and 8 weeks, were offered diets based on oatmeal together with up to 500 g kg?1 of ground oat husk, or 500 g kg?1 of ground barley straw or 400 g of a purified cellulose. The rabbits gained about 40 g liveweight per day when fed a well-balanced control diet (in which oatmeal, grassmeal, corn oil and fishmeal were the main constituents) and, apart from one occasion, there was no significant reduction in this rate of gain even when the diets offered contained up to 500 g kg?1 of these fibre sources. Food consumption increased from 80 g day?1 to 115 g day?1 as the acid detergent fibre concentration in the diet increased from 39 to 270 g kg?1. Digestible and metabolisable energy contents of the diets fell as the fibre concentration rose but the rabbits were able to adjust their intakes and maintain their daily metabolisable energy intakes constant at about 1100 kJ. The proportion of fat in the body dry matter fell as the fibre concentration in the diet was raised. A minimum dietary fibre content of 100 g kg?1 as measured by the acid detergent fibre or crude fibre techniques is suggested for optimum healthy growth.  相似文献   

12.
BACKGROUND: Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti‐nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio‐diesel and glycerol). RESULTS: The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg?1) than in expeller oil (2.1 g kg?1). Liquid chromatography‐mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg?1) than in cake after being expelled (0.8 g kg?1). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg?1 and 8347 TIU g?1 of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L?1 of crude concentrate obtained from cake. CONCLUSION: Higher amounts of phorbol esters are present in oil than cake but bio‐diesel and glycerol are free of phorbol esters. The other anti‐nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed. Copyright © 2011 Society of Chemical Industry  相似文献   

13.
The main phenolic compounds in six pear cultivars were identified and quantified using high‐performance liquid chromatography/diode array detection (HPLC/DAD) and HPLC/electrospray ionisation mass spectrometry (HPLC/ESIMS). Major quantitative differences were found in the phenolic profiles. The peel contained higher concentrations of chlorogenic acid, flavonols and arbutin than the flesh, where only chlorogenic acid was detected. Total phenolics ranged from 1235 to 2005 mg kg?1 in the peel and from 28 to 81 mg k g?1 in the flesh. Ascorbic acid and dehydroascorbic acid were detected in the peel, whereas only dehydroascorbic acid was present in the flesh. The ranges of vitamin C content were from 116 to 228 mg kg?1 in the peel and from 28 to 53 mg kg?1 in the flesh. The antioxidant capacity was correlated with the content of chlorogenic acid (r = 0.46), while ascorbic acid made only a small contribution to the total antioxidant capacity of the fruit. Copyright © 2003 Society of Chemical Industry  相似文献   

14.
A total of 256 individual food samples were collected in Hong Kong for aluminium testing. Most of food samples were analysed in ready-to-eat form. High aluminium levels were found in steamed bread/bun/cake (mean: 100–320 mg kg?1), some bakery products such as muffin, pancake/waffle, coconut tart and cake (mean: 250, 160, 120 and 91 mg kg?1, respectively), and jellyfish (ready-to-eat form) (mean: 1200 mg kg?1). The results demonstrated that aluminium-containing food additives have been widely used in these food products. The average dietary exposure to aluminium for a 60 kg adult was estimated to be 0.60 mg kg?1 bw week?1, which amounted to 60% of the new PTWI established by JECFA. The main dietary source was “steamed bread/bun/cake”, which contributed to 60% of the total exposure, followed by “bakery products” and “jellyfish”, which contributed to 23 and 10% of the total exposure, respectively. However, the estimation did not include the intake of aluminium from natural food sources, food contact materials or other sources (e.g. drinking water). Although the results indicated that aluminium it is unlikely to cause adverse health effect for the general population, the risk to some populations who regularly consume foods with aluminium-containing food additives cannot be ruled out.  相似文献   

15.
The nutritional value of Telfairia occidentalis seed and seed oil available in local market was studied in rats. The average values of the proximate analysis on dry matter basis were 203 g kg?1 crude protein, 536.3 g kg?1 fat, 39 g kg?1 ash, 95 g kg?1 crude fibre and 43.7 g kg?1 carbohydrate, while the moisture content was 75 g kg?1. The mineral analyses showed that T occidentalis seeds contain potassium (3280 mg kg?1), sodium (1230 mg kg?1), magnesium (60.8 mg kg?1), calcium (60.8 mg kg?1) and iron (13.0 mg kg?1). The oil extracted from the seed sample showed physicochemical properties that suggest its suitability for edible and industrial uses. The oil contained high levels of unsaturated fatty acids, oleic and linoleic, which accounted for 63.22% of total fatty acids recovered, while palmitic acid (27.4% of the oil by weight) was the most prevalent saturated fatty acid in the oil. No trace of eleostearic acid was detected in the oil. The effect on physical appearance, weight gain, organ weight, tissue and plasma cholesterol and triacylglycerol levels was determined in rats fed a diet containing 5% T occidentalis oil. These were compared with those of rats fed a control diet (0% T occidentalis oil) over an 8 week study period. Weekly monitoring of the rats showed good physical appearance and steady weight increase. The test rats were not anaemic and no mortality was recorded. While there was a significantly higher (p < 0.05) level of cholesterol in the heart of test rats compared with the control, there was a significantly lower (p < 0.05) plasma cholesterol level, suggesting that T occidentalis seed oil can be used to lower plasma levels of cholesterol. Histological examination of the sections of the heart, liver, kidney and spleen of the test rats revealed varying degrees of pathology. These include artherosclerotic changes in the walls of vasa vasori and lymphatics in the heart and hyaline degeneration of myofibrils, fatty infiltration of hepatocytes, and glomerular and tubular degeneration in the kidneys. These lesions may have been due to the effect of fatty acids, especially erucic acid, in the seed oil, which at 1.24% (less that the 5% conventional allowable limit for edible oils) may be intolerable for rats and may be unsuitable for human consumption. The seed oil may be used for industrial purposes such as soap making, lubrication and cosmetics for which it is well suited. Copyright © 2004 Society of Chemical Industry  相似文献   

16.
Seventy‐two entire male pigs (40.4 ± 1.0 kg) were used to study the effects of increasing crude fibre (CF) level in the diet and maintaining the digestible energy (DE) content of the diet by increasing dietary fat inclusion on pig performance and nutrient digestibility in a 3 × 2 factorial experiment. Productive performance and nutrient digestibility were determined in individually fed pigs offered expander‐processed pelleted diets ad libitum containing three levels of CF (50, 60 and 70 g kg?1) and two levels of fat supplementation (25 and 50 g kg?1) until slaughter at 100 kg. All diets were expander processed at 105 °C for 5 s at 35 bar pressure having been previously conditioned at 85 °C for 5 s. All diets were formulated to have similar concentrations of digestible energy (13.5 MJ kg?1) and lysine (10 g kg?1) and the fat source was a 60:40 blend of tallow and palm oil. The increase in dietary CF level decreased (P < 0.05) the apparent digestibility of crude protein, organic matter (OM) and energy, while the inclusion of 50 g kg?1 fat decreased (P < 0.01) OM and energy digestibility. The inclusion of 50 g kg?1 fat in the diet increased (P < 0.01) ether extract digestibility at the 50 and 60 g kg?1 CF levels; however, fat inclusion had no effect at the 70 g kg?1 CF level. There was no CF × fat interaction in any growth criteria. The inclusion of 50 g kg?1 fat in the diet significantly reduced (P < 0.05) feed intake (2.28 versus 2.43 kg day?1, SEM 0.039), average daily gain (ADG; 0.877 versus 0.927 kg day?1, SEM 0.017) and DE conversion ratio (36.1 versus 35.0 MJ kg?1, SEM 0.40). The increase in dietary CF level decreased (linear, P < 0.05) feed intake (2.45 versus 2.32 versus 2.29 kg day?1, SEM 0.040), ADG (0.940 versus 0.896 versus 0.872 kg day?1, SEM 0.021) and kill‐out proportion (740 versus 741 versus 730 g kg?1, SEM 3.6). In conclusion, increasing both the CF level and supplementary fat inclusion rate had a negative effect on pig growth performance and nutrient digestibility. © 2002 Society of Chemical Industry  相似文献   

17.
This research gives an insight into the possibility of exploiting the one of the food industry's by‐products – pressed hemp cake. The complete recovery of oil from pressed hemp cake was achieved. Residual oil that remained in cake after pressing was extracted with supercritical CO2 by applying different process parameters. Optimal extraction conditions were determined using response surface methodology. Total pigment contents of the oils obtained were determined. Extraction pressure had the most significant influence on yield and pigment content of extracted hemp cake oil. Depending on the pressure, the chlorophyll a content ranged from 101.11 to 378.28 mg kg?1 and chlorophyll b from 65.14 to 189.78 mg kg?1, while total carotene content was in the range from 33.58 to 132.67 mg kg?1. The remaining oil in pressed hemp cake after supercritical CO2 extraction was determined to be 0.56 ± 0.08% and the defatted cake was rich in proteins and fibre.  相似文献   

18.
Two different chemical methods, sequential extraction with alkali and sodium chlorite and treatment with 4-methylmorpholine N-oxide (MMNO), were applied to the extraction of non-starch polysaccharides (NSP) from the enzymically deproteinated, water-insoluble cell wall materials of sunflower (Helianthus annuus L) meal and palm kernel (Elaeis guineensis Jacq) meal. The NSP content accounted for 550 g kg?1 (sunflower meal) and 750 g kg?1 (palm kernel meal) of the cell wall materials. Neither of the treatments alone was capable of solubilising more than about half of the original NSP. Combined treatment using alkali/chlorite followed by MMNO completely dissolved cell wall material from palm kernel meal, whereas a small residue (40 g kg?1 of original NSP) was left in sunflower meal. Loss of NSP occurred with both methods (total NSP recovery ranging from 88% for alkali/chlorite extraction of sunflower to 64% for MMNO extraction of palm kernel). Due to differences in solubility revealed upon acidification and/or dialysis, extracts became subdivided into precipitates and soulble fractions. The sugar composition of the resulting fractions enabled a tentative identification of teh major non-starch polysaccharides; sunflower meal was found to contain cellulose, (acidic) xylans, polyuronide-containing fractions and xyloglucan; palm kernel meal was found to contain mannans, cellulose and xylans, with the major part of the mannans originating from the endosperm and the xylans being almost exclusively located in the endocarp.  相似文献   

19.
The phenolics in 20 apple cultivars comprising 19 English cider apple varieties and one dessert apple variety were analysed by high‐performance liquid chromatography/tandem mass spectrometry. The cider varieties contained higher levels than the dessert apple and the peel was richer in phenolics than the flesh. The phenolic concentrations ranged between 230 and 4920 mg kg?1 fresh weight in the flesh and between 546 and 6306 mg kg?1 fresh weight in the peel. Fifteen compounds from five different phenolic groups, flavan‐3‐ols, flavonols, anthocyanins, hydroxycinnamates and dihydrochalcones, were detected. The major components in the flesh were 5‐O‐caffeoylquinic acid, procyanidin B2 and (?)‐epicatechin, while (?)‐epicatechin and quercetin glycosides predominated in the peel. Copyright © 2007 Society of Chemical Industry  相似文献   

20.
Nixtamalisation is a widely used food processing method in which whole kernel corn is cooked and steeped in alkaline water. It reduces the amount of fumonisin B1 (FB1) that can be detected after cooking. However, the fate of FB1 during nixtamalisation is not fully understood and potentially toxic reaction products, including matrix-associated “masked” FB1 forms that are not detected by routine analytical methods might remain in nixtamalised corn. To assess how nixtamalisation of whole kernel corn affects fumonisin toxicity, male rats were fed diets containing low, mid or high levels of uncooked (LU, MU, HU) or alkaline cooked (LC, MC, HC) FB1-contaminated corn for 3 weeks. The control diet contained uncontaminated corn only. Apoptotic kidney lesions of the type caused by FB1 were not found in the LC or MC groups. Lesions in the group fed HC were minimal and less severe than those found in the rats fed LU, MU or HU. Furthermore, significantly increased sphinganine and sphingosine concentrations indicative of FB1 exposure were found in the kidneys of the rats given LU, MU or HU. Concentrations were also elevated, but to a lesser extent, in rats fed HC, whereas sphinganine and sphingosine concentrations in rats given LC or MC did not differ from the control group. FB1 concentrations in the LC (0.08?mg?kg?1), MC (0.13?mg?kg?1) and HC (0.37?mg?kg?1) diets were markedly reduced compared with their LU (1.8?mg?kg?1), MU (3.5?mg?kg?1) and HU (4.2?mg?kg?1) counterparts as determined by HPLC (n?= 1 analysis/diet). Taken together, the findings show that nixtamalisation is an effective cooking method for reducing the potential toxicity of FB1 contaminated corn.  相似文献   

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