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1.
Net protein ratio (NPR), predicted-protein efficiency ratio (P-PER), relative NPR (RNPR), and corrected RNPR (CRNPR) of thermally processed red kidney beans were estimated in rats and compared to in vitro protein digestibility-corrected amino acid score (AASIVDP), and computed-protein efficiency ratio (C-PER). Thermal processing had a significant effect on protein intake, NPR, P-PER and CRNPR values of beans. Changes in protein intake suggest that heat processing had an effect on the palatability of the beans. Home-cooked beans and commercially canned beans had higher NPR values than beans autoclaved at 128°C for 20 min, while beans autoclaved at 121°C for 10–90 min had intermediate values. High correlation coefficients between P-PER and C-PER, CRNPR and C-PER, and CRNPR and AASIVDP (r=0·990, 0·992 and 0·960, respectively, P<0·001) were observed.  相似文献   

2.
Forage chemistry can affect intake, digestion, milk production, and manure excretion. Although information is available on the effects of forage protein-binding polyphenols on small ruminant production and manure excretion, little information is available for dairy cattle. The objective of this study was to compare fecal and urinary N excretion of diets formulated with alfalfa (Medicago sativa L.) silage versus condensed tannin-containing birdsfoot trefoil (Lotus corniculatus) or o-quinone-containing red clover (Trifolium pratense L.) silages. Significantly higher concentrations of N were excreted in urine by lactating Holstein dairy cows fed red clover and low-tannin birdsfoot trefoil (8.2 g/L) than by cows fed high-tannin birdsfoot trefoil or alfalfa (7.1 g/L). Fecal N concentrations were similar (33.6 g/kg) among all diets. Dairy cows fed red clover had lower rates of urinary N excretion (5.0 g/h) compared with other forages (6.6 g/h). Fecal N excretion rates were lowest for red clover (4.1 g/h), intermediate for alfalfa (5.8 g/h), and greatest for cows fed high- and low-tannin birdsfoot trefoil (6.4 g/h). The ratio of fecal N to urinary N was highest for high-tannin trefoil, lowest for alfalfa and red clover, and higher in excreta collected in morning than evening. Concentrations of neutral detergent fiber (NDF) in feces, of N in NDF (NDIN) and acid detergent fiber (ADIN), and relative amounts of NDIN and ADIN excreted in feces were significantly higher from cows fed high-tannin birdsfoot trefoil than the other silage types. Study results imply that collection of excreta for environmental studies needs to consider forage polyphenol and diurnal effects on chemistry of dairy excreta.  相似文献   

3.
Knowledge of the effects of cow diet on manure composition is required to improve nutrient use efficiency and to decrease emissions of N to the environment. Therefore, we performed an experiment with nonlactating cows to determine the consequences of changes in cow rations for the chemical characteristics and the traits of the microbial community in the feces. In this experiment, 16 cows were fed 8 diets, differing in crude protein, neutral detergent fiber, starch, and net energy content. These differences were achieved by changing dietary ingredients or roughage to concentrate ratio. After an adaptation period of 3 wk, fecal material was collected and analyzed. Observed results were compared with simulated values using a mechanistic model that provides insight into the mechanisms involved in the effect of dietary variation on fecal composition. Feces produced on a high-fiber, low-protein diet had a high C:N ratio (>16) and had lower concentrations of both organic and inorganic N than feces on a low-fiber, high-protein diet. Fecal bacterial biomass concentration was highest in high-protein, high-energy diets. The fraction of inorganic N in the feces was not significantly different between the different feces. Microbial biomass in the feces ranged from 1,200 to 8,000 μg of C/g of dry matter (average: 3,700 μg of C/g of dry matter). Bacterial diversity was similar for all fecal materials, but the different protein levels in the feeding regimens induced changes in the community structure present in the different feces. The simulated total N content (Ntotal) in the feces ranged from 1.0 to 1.5 times the observed concentrations, whereas the simulated C:Ntotal of the feces ranged from 0.7 to 0.9 times the observed C:Ntotal. However, bacterial biomass C was not predicted satisfactorily (simulated values being on average 3 times higher than observed), giving rise to further discussion on the definition of microbial C in feces. Based on these observations, it was concluded that diet composition affected fecal chemical composition and microbial biomass. These changes may affect the nutrient use and efficiency of the manure. Because the present experiment used a limited number of dry cows and extreme diet regimens, extrapolation of results to other dairy cow situations should be done with care.  相似文献   

4.
Green pods of French beans CV, pant Anupam were blended with distilled water, filtered and extract pH was adjusted to 5.25, 5.65, 5.85, 6.25 or 6.65 using 20 % citric acid or 1 N NaOH. Thermal inactivation times (TIT) of peroxidase were determined by TIT tube method. The corrected F100 [min] and z [°C] at the above five pH values were 1.77 and 15.8, 1.43 and 14.1, 0.95 and 11.0, 0.29 and 8.7, and 0.17 and 8.1, respectively. The corresponding energy of activation values were 157, 177, 218, 286 and 307 KJ mole?1. The actual blanching times in boiling media calculated from the above data were 4.0, 3.5, 2.5, 1.0 and 0.5 min, respectively, showing that blanching requirements of French beans decreased with increase in the pH of the blanching media.  相似文献   

5.
6.
A new Line Intersection (LI) procedure for determining sterilization value (Fo) and quality or nutrient retention (cook value: Co) was developed using the original Equivalent Point Method (O-EPM). Analysis of 30 conventional and 5 simulated thermal curves showed excellent agreement between Fo values determined by the new LI method and the traditional General Method (GM). The new LI method performed better than the O-EPM in yielding more accurate estimates of Fo and Co values as shown by the relatively low errors. The difference between Fo (GM) and Fo (LI) expressed as percent of Fo (GM) for conventional curves ranged from -0.01% to 0.78% while that between Fo (GM) and Fo (O-EPM) ranged from -0.18% to 38.78%. Similar results were obtained for Co values.  相似文献   

7.
A procedure based on Southgate's fractionation scheme with subsequent colorimetric determination of monomeric constituents in the individual fractions was used for the analysis of feces of rats fed with diets supplemented with cereal bran or its fiber components. Prior to fractionation, dehydrated feces were extracted with chloro-form:methanol (2:1) mixture and hot 80% methanol and then subjected to treatment with both amylolytic (MERCK glucoamylase, 60°C, 2 hr) and proteolytic (CALBIOCHEM pepsin, 40°C, 48 hr) enzymes. Colorimetrically determined values of noncellulosic polysaccharides and cellulose (calculated as sums of hexoses, pentoses, and uronic acids) agreed satisfactorily with those determined by detergent fiber analysis. The sums of neutral sugars determined colorimetrically correlated closely with the values obtained by GLC analysis after Saeman's hydrolysis (2 hr with 72% (w/w) H2SO4 at 20°C and 2 hr with 2N H2SO4 at 100°C) of defatted samples. The GLC data were, however, consistently higher, especially those for hexoses; the difference was more pronounced with feces than with tested bran material. Confidence in the analysis was strengthened by the observation that the results of proximate and fiber analyses closely approached 100%.  相似文献   

8.
The influence of high temperature heat treatments on the head yields of rough rice having moisture in the range 18–30% wet basis was investigated using an experimental rotary conduction heating unit with constant agitation. Based on the time-temperature history of bulk grain, reaction kinetic parameters (Fc and zc values) were determined for specified changes in head rice yields for general application. The estimated isothermal heating times (Fc values) were related to the reference bulk grain temperatures (Tref) and initial moisture of rice samples (IMC). The plots of Fc value and Tref led to the determination of zc value and its dependence on the IMC of rough rice.  相似文献   

9.
Forty lactating Holstein cows were fed 0, 5.9, 11.7, or 17.4% processed poultry excreta in total mixed rations. The effect of treatment was evaluated on feed intake, BW, milk yield, and composition. Processes poultry excreta appeared to be well accepted by cows even when included in rations at 17.4% of total DM. Mean DM intake averaged 19.3, 19.7, 19.5, and 19.7 kg/d for cows fed 0, 5.9, 11.7, and 17.4% processed poultry excreta, respectively. Body weight change averaged 2.0, 1.7, -1.7, and 1.4 kg/wk from 90 to 180 d of lactation for cows fed from 0 to 17.4% processed poultry excreta, respectively. Fat-corrected milk (4%) yield was similar among treatment groups, averaging 24.2, 26.1, 24.6, and 25.1 kg/d for cows fed 0, 5.9, 11.7, and 17.4% processed poultry excreta. No differences were found for milk and fat yields of percentage fat among treatment means. No off flavors in milk could be attributed to processed poultry excreta added to feed. Processed poultry excreta fed up to 17.4% of total mixed rations supported both adequate feed intake and high milk yields of mid-lactation cows.  相似文献   

10.
This work introduces the concept of a controlled agitation thermal process to reduce quality damage in liquid‐particulate products during agitation thermal processing. Reciprocating agitation thermal processing (RA‐TP) was used as the agitation thermal process. In order to reduce the impact of agitation, a new concept of “stopping agitations after sufficient development of cold‐spot temperature” was proposed. Green beans were processed in No. 2 (307×409) cans filled with liquids of various consistency (0% to 2% CMC) at various frequencies (1 to 3 Hz) of RA‐TP using a full‐factorial design and heat penetration results were collected. Corresponding operator's process time to impart a 10‐min process lethality (Fo) and agitation time (AT) were calculated using heat penetration results. Accordingly, products were processed again by stopping agitations as per 3 agitation regimes, namely; full time agitation, equilibration time agitation, and partial time agitation. Processed products were photographed and tested for visual quality, color, texture, breakage of green beans, turbidity, and percentage of insoluble solids in can liquid. Results showed that stopping agitations after sufficient development of cold‐spot temperatures is an effective way of reducing product damages caused by agitation (for example, breakage of beans and its leaching into liquid). Agitations till one‐log temperature difference gave best color, texture and visual product quality for low‐viscosity liquid‐particulate mixture and extended agitations till equilibration time was best for high‐viscosity products. Thus, it was shown that a controlled agitation thermal process is more effective in obtaining high product quality as compared to a regular agitation thermal process.  相似文献   

11.
The dissipation of bifenthrin, lufenuron, and iprodione was studied in green beans, peas, and chilli peppers under Egyptian field conditions. For this purpose, three specific and one multi-analyte liquid chromatography-electrospray ionization-tandem mass spectrometry methods were developed and validated according to SANCO guidelines for the determination of bifenthrin, iprodione, and lufenuron residues in the selected commodities. Sample preparation was carried out by the QuEChERs approach, and determination was performed in positive ionization mode for iprodione and bifenthrin and in negative mode for lufenuron. Optimization of the ionization parameters and the chromatographic conditions was performed for each method developed. All methods showed satisfactory performance criteria. Linear dynamic range, limits of detection (LOD) and quantification (LOQ), precision, recovery, and matrix effects were estimated, and the calculated LODs were in the micrograms-per-kilogram range, namely 0.14, 0.61, and 1.4 μg/kg for bifenthrin, lufenuron, and iprodione, respectively. Field trials were carried out in one of the biggest farms in Egypt (Blue Nile) that exports significant quantities of vegetables to the European Union (EU) countries. All the examined pesticides showed high degradation rates. The t 1/2 values for bifenthrin were 3.3, 2.1, and 9.6 days in green beans, peas, and chili peppers, respectively. For iprodione, they reached 2.4 and 14.4 days in green beans and peppers. Furthermore, the calculated pre-harvest interval (PHI) values, according to the maximum residue limits set by EU, were 0, 4, and 0 days for bifenthrin in green beans, peas, and peppers, respectively, and for iprodione, 2 days in green beans and 0 days in peppers. In case of lufenuron, no t 1/2 and PHI were estimated as no residues were found in all pea samples.  相似文献   

12.
Freshwater prawn in curry was thermally processed to three F0 values of 6, 8, and 9 at 116°C. Total process times for F0 values of 6, 8, and 9 were 53, 57, and 63 min, respectively. The cook value (CV) obtained at F0 values of 6, 8, and 9 was 87.53, 107.93, and 117.55 min, respectively. Instrumental texture profile analysis revealed that except springiness, the values of hardness, gumminess, and chewiness decreased as the F0 values increased. CIELAB values of L*, b*, and a* increased as the F0 values were increased. The organoleptic evaluation scored the highest for the product processed to F0 7 min.  相似文献   

13.
Effects of forage source, concentration of metabolizable protein (MP), and type of carbohydrate on manure excretion by dairy cows and production of ammonia from that manure were evaluated using a central composite experimental design. All diets (dry basis) contained 50% forage that ranged from 25:75 to 75:25 alfalfa silage:corn silage. Diets contained 10.7% rumendegradable protein with variable concentrations of undegradable protein so that dietary MP ranged from 8.8 to 12%. Starch concentration ranged from 22 to 30% with a concomitant decrease in neutral detergent fiber. A total of 15 diets were fed to 36 Holstein cows grouped in 6 blocks. Each block was a replicated 3 × 3 Latin square resulting in 108 observations. Manure output (urine and feces) was measured using total collection, and fresh feces and urine were combined into slurries and incubated for 48 h to measure NH3-N production. Feces, urine, and manure output averaged 50.5, 29.5, and 80.1 kg/d, respectively. Manure output increased with increasing dry matter intake (∼3.5 kg of manure/kg of dry matter intake), increased concentrations of alfalfa (mostly via changes in urine output), and decreased concentrations of starch (mostly via changes in fecal output). The amount of NH3-N produced per gram of manure decreased with increasing alfalfa because excreted N shifted from urine to feces. Increasing MP increased NH3-N produced per gram of manure mainly because of increased urinary N, but increased fecal N also contributed to the manure NH3. Manure NH3-N production per cow (accounts for effects on manure production and NH3-N produced per unit of manure) was least and milk protein yields were maximal for diets with high alfalfa (75% of the forage), moderate MP (11% of diet dry matter), and high starch (30% of diet dry matter).  相似文献   

14.
The objective of this study was to determine the effect of replacing on isonitrogenous and isoenergetic basis soybean meal (SBM) and corn grain with ground or rolled faba bean (FB; Vicia faba major var. Baie-Saint-Paul) in dairy cow diets (17% of diet dry matter) on nutrient digestion, rumen fermentation, N utilization, methane production, and milk performance. For this purpose, 9 lactating cows were used in a replicated 3 × 3 Latin square design (35-d period) and fed (ad libitum) a total mixed ration (forage:concentrate ratio = 59:41 on a dry matter basis). In the concentrate portion, SBM and corn grain (control diet) were completely and partially replaced, respectively, with either ground or rolled FB. Ruminal degradability (in sacco) of crude protein was higher for ground FB (79.4%) compared with SBM (53.3%) and rolled FB (53.2%). Including FB in the diet did not affect dry matter intake, milk production, and milk composition. Experimental treatment had no effect on total volatile fatty acid concentration, acetate-to-propionate ratio, and protozoa numbers. Compared with cows fed the control diet, ruminal NH3 concentration increased and tended to increase for cows fed ground FB and rolled FB, respectively; however, we found no difference in ruminal NH3 concentration between the 2 processed FB. Apparent total-tract digestibility of crude protein was similar between cows fed the control diet and cows fed rolled FB and tended to increase for cows fed ground FB compared with cows fed the control diet. Feeding rolled FB decreased CP digestibility compared with feeding ground FB. Urinary and manure (feces + urine) N excretion (g/d or as a proportion of N intake) were not affected by the inclusion of FB in the diet. Enteric CH4 production was similar among the experimental diets. Results from this study show that including FB (17% of dietary dry matter) at the expense of SBM and corn grain in the diet had no effect on milk production, N excretion, and enteric CH4 production of dairy cows.  相似文献   

15.
本实验采用高效液相色谱仪(high performance liquid chromatography,HPLC)、色差仪、电子鼻分别检测未发酵、发酵和焙烤海南可可豆的总酚含量、总黄酮含量、色度和可可豆风味差异。结果表明:未经焙烤的未发酵豆总酚(464.03 mg/10 g)和总黄酮(126.86 mg/10 g)含量明显高于发酵豆总酚(211.86 mg/10 g)和总黄酮(61.98 mg/10 g)含量。105~145 ℃焙烤30 min,未发酵豆总酚和总黄酮含量分别为419.5~129.8 mg/10 g和77.8~16.8 mg/10 g;发酵豆总酚和总黄酮含量分别为182.53~86.25 mg/10 g和34.7~7.0 mg/10 g。其中,125 ℃焙烤20~40 min,未发酵豆总酚和黄酮含量分别为353.74~289.45 mg/10 g和42.86~32.20 mg/10 g;发酵豆总酚和黄酮含量分别为152.08~123.55 mg/10 g和25.12~21.14 mg/10 g。在105~145 ℃的温度焙烤下没食子酸含量变化显著。可可豆色度值的范围:L*值集中在40.0~47.0之间,a*值集中在5.0~6.8之间,b*值集中在4.0~8.5之间。未发酵和发酵可可豆之间,以及不同温度焙烤可可豆之间的电子感官风味分析结果差异较大。  相似文献   

16.
Faba beans (Vicia faba L.) of four cultivars, one of which was harvested in batches during the 2 months prior to normal harvesting time, and for comparison, a sample of kidney beans (Phaseolus vulgaris L.) had similar amino acid compositions with sulphur amino acids limiting in all samples. Chemical scores ranged from 45–52 and all the faba beans, when fed to rats, gave biological values in close agreement with the chemical score. Diets containing two of the cultivars were supplemented with 0.1% methionine and in both instances an increase in biological value of 22 units was obtained. Kidney beans fed to rats at the same level of crude protein resulted in the death of animals in 7–9 days. The haemaggfulinin content of the faba bean samples was 8–16 times lower than in kidney beans. Early harvesting did not affect the nutritive value of the faba beans and no differences were observed between the different cultivars, none of which showed any evidence of toxicity.  相似文献   

17.
Starch samples from ten mung bean cultivars grown in china were isolated, and their morphology, physicochemical, thermal, and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different mung bean varieties, and to establish the basic foundation of improving the functionality of mung beans and their starch grown in the region. The mung bean starches showed the kidney-shaped, elliptical, small spherical and dome-shaped granules, and the starches granule size varied between 5 and 40 μm. Total starch content, amylose content, solubility, and swelling power ranged from 54.73% to 57.99%, 40.44% to 41.82%, 13.72% to 17.67%, and 17.27% to 20.55%, respectively. The pasting properties were determined using a rapid visco analyzer, and various mung bean starches exhibited different pasting profiles. Different starches differed in transition temperatures (T o, T p, and T c), gelatinization temperature range (ΔT r), and enthalpy of gelatinization (ΔH) according to differential scanning calorimeter analysis. Hydration coefficient, degree of gelatinization, and hardness of mung bean varieties ranged from 51.97% to 84.46%, 62.99% to 95.11%, and 26.07 N to 112.11 N, respectively. This study indicated that starches separated from different mung bean cultivars possess different physicochemical characteristics, and various mung beans cultivars showed diverse processing properties.  相似文献   

18.
Thermal processing as the most prevalent food preservation technique has been extensively studied and used for years. Different modes of agitation that can be employed in the canning process are characterized by relatively different, heat impacts and their associated quality changes. Hence, the main objective of this study was to evaluate the impact of different retort conditions on lethality (Fo), color and textural changes in potato cubes. Process variables employed were: retort temperature: 115, 120, 125 ºC; agitation orientations: vertical (end-over-end) and horizontal (fixed and bi-axial); agitation speed: 0 (static), 10, 20 rpm. A water immersion single basket rotary retort was retrofitted to simultaneously accommodate agitating modes of rotation. Accumulated process lethality values were calculated for each experimental run. Color quality in terms of parameters such as, yellowness (b-value), total color difference (ΔE values) and textural quality in terms of hardness values were compared for the particles processed under each condition. All process variables had a significant (p < 0.05) influence on Fo, color and texture parameters of potato particles. The quality changes were found to correlate well with the accumulated Fo values achieved during processing. As can be expected, the quality loss increased with an increase in Fo and vice versa.  相似文献   

19.
This study was carried out to investigate the hypolipidemic and hypoglycemic potential of raw, boiled, and sprouted mung beans in rats. Oven dried mung bean powders; raw, sprouted, and boiled were included at 30% level in the diet of seven weeks old male Wistar rats maintained for 5 weeks on high (0.5%) cholesterol diet in comparison with control diet. Low serum glucose and triglyceride concentrations (p < .05) in raw and processed mung bean diets fed rats were supported by low serum insulin level in both raw mung bean diet and boiled mung bean diet fed rats. Hypoglycemic effect in sprouted mung bean fed rats was supported by higher α‐amylase inhibitory activity and α‐glucosidase inhibitory activity of sprouted mung beans. Increase in serum non‐HDL cholesterol concentration and decrease in HDL cholesterol concentration caused by high cholesterol diet were modulated (p < .05) by both boiled and sprouted mung bean diets.

Practical applications

Mung bean is a green legume rich in protein, fiber, antioxidants, and phytonutrients. Hypocholesterolemic and hypoglycemic potential of raw mung beans have been shown previously. It is well known that cooking and processing modulate nutritional and biochemical parameters of foods. However, very limited information is available on the effect of processing on functional properties of legumes. Results of this study showed that boiling and sprouting improved the soluble fiber content and hypocholesterolemic potential of mung beans. Thus, the processed mung beans may be more suitable for developing food supplements for patients with hypercholesterolemia.  相似文献   

20.
African locust beans (Parkia filicoidea Welw.) were processed and fermented to the traditional West African condiment dawadawa. The beans were transformed to ‘processed substrate’ by boiling and dehulling, and then fermented at 37°C in static fermenter units. The overall mass balance and the mass balances of several bean components (moisture, fat, protein, ash and carbohydrate) were studied. It was found that 1.0 kg of raw beans (6.4% moisture) yielded 1.3 kg of processed substrate (63% moisture) which in turn was converted to 1.2 kg of dawadawa (65% moisture). The loss of bean solids during processing was due to the removal of adhering pulp and testa as well as to solids extraction during boiling and washing. Overall, 57% of the bean dry weight, 85% of the carbohydrate, 48% of the ash, 40% of the protein and 1% of the fat were lost in the conversion of raw beans to dawadawa. The dawadawa had considerably higher fat and protein contents than the raw beans and was a pleasant tasting food whereas the raw beans were inedible. Some microbiological aspects of the fermentation were also investigated. Normally prepared fermentation substrate was compared with both sterilised and radappertised beans in terms of conversion to dawadawa, number of colony forming units present, and the development of pH and titratable acidity. The presence of microorganisms was found to be obligatory for the conversion to proceed. Simultaneous increases in both pH and titratable acidity were observed during the fermentation.  相似文献   

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