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1.
The aim of the experiment was to investigate the effect of partial or total substitution of wheat flour with oat meal and tapioca starch in extruded salmon feed. A mixture design (simplex centroid mixture design) was used to analyse the effect of starch source on physical quality of extruded feed. Physical quality of the extruded feed was evaluated as cohesiveness, pellet density, axial and radial expansion, durability, hardness, strain at rupture and elastic modulus. Starch sources affected behaviour of the diet formulations during extrusion and caused changes in the physical properties of the extruded products. Significant correlations (P < 0.05) between physical properties and weight fraction of the starch sources allowed the establishment of predictive models. The inclusion of oat meal and tapioca starch in the diet gave extruded feed with a higher porosity and lower oil absorption capacity. The mechanical properties of the extruded feeds were significantly different from each other, most likely due to the complex nature of texture formation with respect to process parameters and properties of ingredients.  相似文献   

2.
ABSTRACT

Extrusion cooking plays an important role in the production of puffed snacks, which enjoy wide acceptance all over the world and are potential vehicles for increasing the consumption of n-3 fatty acids. Response surface methodology (RSM) with central composite design was adopted to investigate the effects of four independent variables (fish powder, fish oil, moisture, and screw speed) at five levels on expansion ratio, breaking strength index, hardness, color, and thiobarbituric acid reactive substances (TBARS). A second order polynomial model was used to study the main, interactive, and quadratic effects of the independent variables and to explain the relationship between the responses and independent variables. Moisture was found to be the most significant factor (p < 0.001) influencing expansion ratio, breaking strength index, and color. Inclusion of fish powder and fish oil were found to be negatively associated with the expansion characteristics, resulting in decreased lipid oxidation due to less exposed surface area of the extrudates to air. Further, the absence of linear effect of fish powder and fish oil on TBARS demonstrated the possibility to incorporate higher levels of these ingredients to produce oxidatively stable extruded snacks rich in fish proteins.  相似文献   

3.
Starch was isolated from lotus stem obtained from three lakes of Jammu and Kashmir, India, and their physicochemical, morphological, and pasting properties were studied. Protein, fat, and amylose content varied significantly (p ≤ 0.05) among the different starches, but no significant difference was found in ash content. Amylose content was highest in lotus stem starch from Manasbal (30.0%), followed by the Dal (28.3%), and the Wular (25.0%). Functional properties like swelling, solubility, and water absorption showed an increasing trend with an increase in temperature from 50–90°C. Scanning electron microscopy of lotus stem starches showed small rounded and typical oval shaped granules with a smooth surface. The starch extracted from Wular and Dal lotus stems had larger granules than Manasbal starch. All the starches obtained from the three sources gave a similar B-type X-ray diffraction pattern. Pasting properties—such as pasting temperature, peak viscosity, breakdown, setback, and final viscosity—significantly differed among starches.  相似文献   

4.
不同淀粉源对水产膨化饲料加工及品质特性影响研究进展   总被引：1，自引：0，他引：1  
杨洁  李军国  许传祥  王昊  马世峰  薛敏 《水产学报》2019,43(10):2102-2108
淀粉在水产膨化饲料加工过程中起着非常重要的作用,不仅能增强物料的粘性,在膨化饲料中起到膨胀和粘合的双重作用。由于不同来源淀粉的颗粒结构不同,其对水产膨化饲料加工和品质等产生的影响也存在差异。本研究综述了不同淀粉源的基本特性与水产膨化饲料加工及品质特性之间关系的研究进展,分析不同淀粉源淀粉的组成、结构、糊化特性、流变特性和热力学特性等方面的差异,比较不同淀粉源对水产膨化饲料品质特性的影响,并对不同淀粉源在研究过程中存在的问题、发展方向进行展望。  相似文献   

5.
Two 8‐week feeding trials were conducted to evaluate dietary carbohydrate utilization by omnivorous gibel carp (Carassius auratus gibelio) (2.4 ± 0.1 g) and herbivorous grass carp (Ctenopharyngodon idellus) (6.5 ± 0.1 g). Five isonitrogenous (370 g kg?1) and isolipid (70 g kg?1) diets were formulated with increasing corn starch levels (60, 140, 220, 300 and 380 g kg?1). Results showed that specific growth rate (SGR), feed efficiency (FE) and protein retention efficiency (PRE) of gibel carp significantly increased from dietary starch of 60 to 300 g kg?1 and then decreased from 300 to 380 g kg?1, but those of grass carp showed no significant differences between treatments. Independent of dietary starch levels, grass carp gained significantly higher FE and PRE than gibel carp. Feeding rate (FR) of gibel carp was significantly higher than that of grass carp. In two fish species, high dietary starch (300 and 380 g kg?1) tended to obtain higher hepatosomatic index (HSI), serum triglyceride, hepatic lipid and body lipid contents. Serum glucose concentration of grass carp was not affected, while that of gibel carp fed the starch of 300 g kg?1 diet was significantly lower than those of the fish fed other four diets (60, 140, 220 and 380 g kg?1). Grass carp showed high tolerance to dietary starch while dietary corn starch should be no more than 300 g kg?1 for gibel carp. High starch contents may cause lipid accumulation in the liver and body.  相似文献   

6.
The effect of dietary starch source and level on growth performance, feed utilization, apparent digestibility coefficients and liver enzyme activities involved in intermediary metabolism of gilthead sea bream juveniles was studied. Five isonitrogenous (47% crude protein) and isolipidic (15% crude lipids) diets were formulated to contain 10% native (diet NS10) or waxy (diet WS10) maize starch; 20% native (diet NS20) or waxy (diet WS20) maize starch or no starch (control). Diets were adjusted with α-cellulose. Another diet was formulated without carbohydrates, and contained 70% crude protein and 15% crude lipids (diet HP). Each diet was fed to triplicate groups of 30 fish (initial weight: 20 g) for 12 weeks. The HP group was fed to near satiation and the other 5 groups were fed on a pair-feeding scheme according to the group that ingested less feed (control diet group). The reduction of dietary protein level from 70% to 47% by the incorporation of 20% starch did not significantly affect gilthead sea bream growth performance or feed efficiency. Compared to the control diet, neither the level nor the nature of starch had any measurable effect on growth performance and feed efficiency. Digestibility of starch was unaffected by source or dietary inclusion level. Diet had no effect on plasma glucose levels, but liver glycogen was higher in diet groups NS20, WS20 and HP. Dietary carbohydrates increased GK and G6PD enzyme activities and decreased ALAT and GDH enzyme activities while had only a minor effect on FBPase activity. The nature of dietary starch tested (native or waxy) had little influence on performance criteria.  相似文献   

7.
This study examined the effects of different surimi-to-silver catfish ratios (0/100, 20/80, 40/60, 60/40, 80/20, and 100/0) and potato starch concentrations (3, 5, and 7%) on the properties of fish sausage. The surimi-to-catfish ratio affected the moisture, fat, protein, and ash content of the sausage; as well as cooking loss, greenness, lightness, and hardness. Different concentrations of potato starch affected carbohydrate content, springiness, and yellowness. The most acceptable formulation was the 40/60 surimi-to-catfish ratio with 7% potato starch. Vacuum-packed fish sausages from all formulations had low peroxide and 2-thiobarbituric acid (TBA) values during 12 days of refrigerated storage.  相似文献   

8.
This study examined the influence of different lupin species and cultivars and their inclusion levels on the physical properties of an extruded diet. Lupin kernel meals were included into a fish diet formulation at 0%, 10%, 20% and 30%. Soybean meal was also included in a series of diets on a similar basis as a reference. The diet mashes were extruded using a laboratory-scale APV19:45 twin-screw extruder. The pellets were examined for radial expansion, bulk density, vacuum oil uptakes, sink rate, shear and crush strengths. Inclusion of lupin kernel meal significantly increased bulk density, sink rate, shear and crush strength of the pellets. With the increase in lupin kernel meal inclusion level, a concomitant decline in vacuum oil uptake and radial expansion was also observed. An assessment of the diet mashes using a Rapid Visco Analyser showed that the inclusion of lupin kernel meals increased the rate and degree of gelatinization of the mash starch content compared with that with a similar inclusion level of soybean meal. The inclusion of lupin kernel meals in the diet mash also improved the water-holding capacity of the extrudate, which has important implications for the reduction in extruder wear.  相似文献   

9.
A growth trial was conducted to feed juvenile tilapia (initial weight, 9.1±0.1 g), Oreochromis niloticus×O. aureus, isonitrogenous diets for 8 weeks. Six diets were formulated containing 29% crude protein from casein and gelatin, 10% crude fat from soybean oil and refined soybean lecithin and varying levels of corn starch ranging from 6% to 46% at increments of 8%, with corresponding energy to protein (E/P) ratios of 35.6, 37.9, 40.2, 42.5, 44.8 and 47.1 kJ g?1. Weight gain (WG), specific growth rate, feed efficiency ratio and protein efficiency ratio were significantly higher in fish fed diets with starch ≥22% (or E/P ratio ≥40.2 kJ g?1) than in fish fed diets with 6% or 14% starch (or E/P ratio of 35.6 or 37.9 kJ g?1). No further improvement was measured when dietary starch content increased beyond 22%. Body protein retention showed the same general pattern as WG, and was highest in fish fed the 22% starch diet. Body composition was significantly affected by dietary starch level. Fish fed diets with starch ≥30% had significantly higher lipid content than fish fed diets with 6% or 14% starch. Ash content was negatively correlated with starch inclusion level, but moisture and protein contents did not show discernible trends among treatments. Results indicate that hybrid tilapia can utilize 46% dietary starch without growth retardation, while 22% starch in feed for juvenile tilapia containing 29% protein and 10% lipid, or an E/P ratio of 37.9 kJ g?1 is optimal.  相似文献   

10.
This study determined whether accumulated liver and visceral lipid in yellow perch can be alleviated by feeding an appropriate starch source. We compared the growth performance, nutritional composition and health of yellow perch fed a control diet (no added starch) and three diets with corn, potato or wheat starch (200 g/kg diet) to replace an equal proportion of fishmeal in the control diet. Dietary starch led to increased bulk density, hardness and gelatinization levels of feed pellets compared with the control diet. At the end of an 8‐week feeding, all fish fed the test diets had similar growth rates (p > .05). However, the wheat starch diet resulted in significantly enlarged livers and increased accumulation of lipid in the liver, viscera and whole body (p < .05). This diet also caused significantly higher levels of fasting glucose, aspartate aminotransferase and alkaline phosphatase activities in serum than the control diet. Liver cell diameters were larger, and Kupffer cell numbers were lower in the fish fed the wheat starch than those fed the control diet. Potato or corn starch had less impact on fish health and is considered to be an appropriate carbohydrate sources for yellow perch under the current testing conditions.  相似文献   

11.
The aim of this study was to investigate the impact of two types of fish raw material on fishmeal (FM) physicochemical properties, specific mechanical energy, starch gelatinization and physical feed quality. Eleven feed mixes based on six independent FMs from herring (FMH) and five from sand eel (FMSE) were extruded according to standardized conditions. Type of fish raw material influenced FM physicochemical properties and had significant impact on starch gelatinization and pellet hardness. Multivariate models were established based on partial least squares regression (R2 = 0.637–0.999). Improved degree of starch gelatinization was associated with increased degree of protein hydrolysis (P = 0.011) and by replacement of FMH with FMSE in the feed mix (P = 0.012). A large span in pellet hardness was observed (4.9–94.1 N). Improved hardness was associated with decreased level of non‐soluble protein (P < 0.001) and by replacement of FMSE with FMH (P < 0.001). For FMSE, improved hardness was associated with decreased level of non‐soluble protein (P < 0.001) and increased degree of protein hydrolysis (P = 0.002), compressed bulk density (P = 0.039) and dust fraction (P = 0.001). The underlying physical and chemical mechanisms are discussed. The study documents differences in technical quality of FM produced from herring and sand eel with significant impact on fish feed extrusion and pellet quality.  相似文献   

12.
葡萄糖和玉米淀粉对草鱼生长和肠系膜脂肪沉积的影响   总被引：2，自引：0，他引：2  
田丽霞 《水产学报》2000,24(5):438-441
采用30%葡萄糖或玉米淀粉作为糖源的配制两种纯化饲料,饲养初始体重为(35.94±1.86)g的两组草鱼,经过为期9周的生长试验,观察葡萄糖和玉米淀粉对草鱼生长和肠系膜脂肪沉积的影响.实验结果显示摄食葡萄糖饲料的草鱼其相对生长率、饲料效率和蛋白质效率均显著高于玉米淀粉组,而肠系膜脂肪占鱼体的百分比在葡萄糖饲料组和淀粉饲料组之间存在显著性差异,分别为1.85%±0.46%和3.56%±0.45%.由此可见,葡萄糖比玉米淀粉对草鱼的生长具有更好的作用,而玉米淀粉比葡萄糖更容易引起草鱼肠系膜脂肪沉积的增加.  相似文献   

13.
田丽霞 《水产学报》2002,26(3):247-251
将试验草鱼随机分配在 12个水族箱中 ,每箱放鱼 30尾 ,分别以玉米淀粉、小麦淀粉、水稻淀粉为糖源配制 3种试验饲料 ,饲养初始体重为 (8.49± 0 .0 4)g的草鱼 80d ,观察不同种类淀粉饲料对草鱼生长、肠系膜脂肪沉积和鱼体组成的影响。每种饲料设 3个平行组 ,日投喂率按鱼体重的 3%计算。试验结果显示 :尽管草鱼对糖的表观消化率以小麦淀粉组最高 ,但摄食小麦淀粉饲料的草鱼与摄食玉米淀粉和水稻淀粉饲料的草鱼在生长上并无显著性差异。然而小麦淀粉组和玉米淀粉组的内脏比、肝胰脏脂肪含量、血浆甘油三酯水平以及肠系膜脂肪占鱼体的百分比显著高于水稻淀粉组 (P <0 .0 5 )。鱼体营养成份组成除了水稻淀粉组全鱼脂肪含量相对低于玉米淀粉组和小麦淀粉组之外 ,其它成份没有太大的差异。  相似文献   

14.
Four extruded diets, differing in grain supplementation, were fed to triplicate groups of Atlantic salmon ( Salmo salar , L.) with a mean weight of 0.5 kg in a digestibility trial. The diets contained 100 or 150 g kg−1 of precooked rye or wheat, replacing fish meal. There were no significant differences in apparent digestibility coefficients (ADC) of protein, fat or starch which could be related to dietary carbohydrate source or inclusion level. The ADC of dry matter and energy were higher for the diets with wheat than for those with rye, and higher for the diets with wheat than for those with rye, and higher for the diets with 100 g precooked grain kg−1 than for those with 150 g kg−1. The mean ADC of starch was 52% for rye, and 53% for wheat.  相似文献   

15.
Carbohydrate utilization by fish varies with feeding habits and feed processing. Extruded aquafeeds have increased digestibility of carbohydrate sources resulting from the cooking and gelatinization of this nutrient, making it readily available for all aquatic species. This study aimed at determining the effects of extrusion cooking of feeds in the digestibility of different dietary carbohydrate sources for dourado. Isonitrogenous and isoenergetic diets (530 g kg?1 crude protein and 20.80 MJ kg?1 gross energy) containing either corn, toasted cassava flour, wheat flour, broken rice, cassava starch, or corn starch, in extruded or pelletized form and added of chromic oxide as inert marker, were fed to groups of juvenile dourado (73.97 ± 12.0 g; n = 40) stocked in 500‐L polyethylene tanks. Extrusion cooking improved the digestibility of energy and/or starch of corn, cassava starch, wheat flour, rice and corn starch (P < 0.05), but did not affect digestibility of toasted cassava flour (P > 0.05). It is thus fair to infer that dourado, despite being a carnivorous species, is properly fit to digest wheat flour, rice and corn starch in natural form.  相似文献   

16.
This study was performed to determine compensatory growth of juvenile olive flounder fed the extruded pellet (EP) with different feeding regimes. Seven treatments with triplicates of different feeding regimes were prepared; α fish was daily fed for 6 d a week throughout 8 wk (8WF); α fish was starved for 1 wk and then fed for 3 wk twice [(1WS + 3WF) × 2]; β fish was starved for 2 wk and then fed for 6 wk (2WS + 6WF); χ fish was starved for 5 d and then fed for 9 d four times [(5DS + 9DF) × 4]; δ fish was starved for 10 d and then fed for 18 d twice [(10DS + 18DF) × 2]; δ fish was starved for 2 d, fed for 5 d, starved for 3 d, and then fed for 4 d four times [(2DS + 5DF + 3DS + 4DF) × 4]; and φ fish was starved for 4 d, fed for 10 d, starved for 6 d, and then fed for 8 d twice [(4DS + 10DF + 6DS + 8DF) × 2], respectively. Total feeding day was all same, 36 d except for control group (48 d). Weight gain of flounder in the 8WF treatment was higher than that of fish in other treatments. And weight gain of flounder in the 2WS + 6WF treatment was higher than that of fish in the (5DS + 9DF) × 4 and (4DS + 10DF + 6DS + 8DF) × 2 treatments. Feed consumption of flounder in the 8WF treatment was higher than that of fish experienced feed deprivation. Feed efficiency ratio (FER), protein efficiency ratio (PER), and protein retention (PR) were not significantly different among treatments. Chemical composition of the whole body of fish with and without liver, except for moisture content of liver, was not different among treatments. T3 level of fish in the 8WF and 2WS + 6WF treatments was higher than that of fish in the (5DS + 9DF) × 4 treatment. It can be concluded that juvenile olive flounder achieved better compensatory growth at 6‐wk refeeding after 2‐wk feed deprivation compared with that of fish with different feeding regimes. And T3 level of fish seemed to partially play an important role in achieving compensatory growth.  相似文献   

17.
Raw corn starch (RCS), raw tapioca starch (RTS), raw potato starch (RPS), pre‐gelatinized corn starch (PCS), pre‐gelatinized tapioca starch (PTS) and pre‐gelatinized potato starch (PPS) were evaluated as starch sources in diets for yellowfin seabream Sparus latus in a 56‐day growth trial. Seven isonitrogenous semi‐purified diets comprising a non‐starch cellulose control diet and the six different starch sources holding 200 g kg−1 starch each were prepared and fed to triplicate groups of juvenile yellowfin seabream S. latus. Fish were fed for 8 weeks. Weight gain (WG) and specific growth rate (SGR) for fish fed RCS, RTS and RPS diets were equal, as well as for fish fed PCS, PTS and PPS diets, but values in groups fed the raw starch sources were significantly higher compared with fish fed the pre‐gelatinized starches. Feed efficiency and protein efficiency ratio in fish fed different starch source diets showed no significant differences but were significantly higher than those fed a non‐starch control diet. Protein productive value was improved by starch incorporation to diets. PCS, PTS or PPS groups showed lower feed intake compared with RCS, RTS or RPS groups, and the differences were significant between PCS, PPS and RCS, RPS groups. Whole‐body protein and ash contents and muscle compositions were not affected by different starch sources. Whole‐body and liver lipid contents, liver moisture and glycogen contents were significantly affected by starch source. Values of hepatosomatic index, intraperitoneal fat ratio, viscerosomatic index and condition factor did not vary between experimental treatments. Plasma total protein concentration for RCS, RTS or RPS fed fish was significantly higher than that for PCS, PTS or PPS fed fish, but significantly lower than that for non‐starch fed fish. Plasma cholesterol and triacylglycerol concentrations were unaffected by starch source, but were significantly higher in fish fed the non‐starch control diets. Plasma glucose concentrations in all dietary groups were relatively stable. In conclusion, raw corn, tapioca and potato starches at a 200 g kg−1 inclusion level were well utilized as energy sources by yellowfin seabream, which was evidenced by better WG and SGR. Pre‐gelatinization of the starches had no positive effect on starch utilization.  相似文献   

18.
Six diets were formulated to contain corn starch, tapioca starch, or dextrin at 10% and 20% inclusion levels and fed to humpback grouper fingerlings to apparent satiation for 10 weeks. Growth and feed utilization efficiency of humpback grouper were not affected by dietary carbohydrate source and level. Only slightly higher growth was observed in fish fed 20% dietary carbohydrate compared to the fish fed 10% carbohydrate irrespective of carbohydrate source. Body indices and whole body proximate composition of fish in the present study were generally independent of diet, except that muscle lipid of fish fed diets with 7.6% lipid and 20% carbohydrate was significantly lower than the other groups. In view of the lower price and local availability of tapioca starch compared to corn starch and dextrin, tapioca starch is the preferred source of starch in practical diets for humpback grouper.  相似文献   

19.
The present study evaluated how different photoperiods, carbohydrate sources and inclusion levels influenced growth, plasma, organ and body compositions in Atlantic salmon (Salmo salar). Four different diets were used, containing 10 or 20% starch on a dry matter basis, using gelatinized corn (C10 and C20) or wheat (W10 and W20). Two different photoperiods were used, Continuous (Con) light throughout the study, Winter (Wi) two initial weeks of continuous light, thereafter 6 weeks of short day, ending with 6 weeks of continuous light. The winter regime resulted in reduced growth rate compared with continuous light. All Wi groups were smaller than Con groups when the experiment was terminated, except for fish given diet C10. Diet W10 resulted in better growth compared with all other groups when exposed to Con. regime. Atlantic salmon fed with diets containing 20% starch had lower growth rates than fish fed diets containing 10% starch, when the same starch source and light regime were compared. All fish belonging to the Con group exhibited similar and higher condition factors compared with fish from groups Wi. Condition factor was not influenced by dietary starch source. Higher whole body lipid concentrations were found when fish were given the corn compared with the wheat diets, without any responses to starch level or light regime. Whole body protein showed increased values in fish exposed to regime Wi compared with Con, without any influence from dietary manipulation. Liver glycogen values and hepatosomatic index reflected dietary starch levels and were significantly influenced by light regime, whilst muscle glycogen levels varied only as a response to light regime with lower values in fish from the Wi compared with the Con groups. Light regime influenced plasma glucose levels, except in groups fed with diet W10. All measured plasma nutrient concentrations were within normal ranges. At the end of the feeding period, all fish were evaluated for glucose and salt water tolerance to ascertain whether diet and/or light regime influenced glucose regulation capacity and/or smolt quality. Fish fed with 20% starch had reduced osmoregulatory ability measured as plasma chloride after a seawater challenge test. Fish from the Wi regime, but not from the Con regime developed characteristics associated with smoltification. Glucose tolerance in Atlantic salmon was substantially influenced by both photoperiod regime and diet. Fish reared under the Wi photoperiod showed reduced glucose regulation capacity compared with fish held under continuous light. Glucose regulation capacity was also reduced in fish adapted to the highest starch levels.  相似文献   

20.
Two extruded diets designed to have fat levels of 220 g kg−1 (F22) and 300 g kg−1 (F30) were fed to Atlantic salmon Salmo salar L. in two different experiments during the sea rearing period (from 0.2–0.3 kg to 3–4 kg). Each diet was fed restricted and isoenergetically at two feeding rates to fish in triplicate groups. In one of the experiments, a supplementary group of fish was fed to satiation with the F30 diet. All fish were slaughtered and evaluated for quality according to a commercial standard.
No difference in growth was observed between fish fed the two diets at similar feeding rates and the growth was proportional to the amount of dietary energy offered. Feed conversion ratios decreased according to higher energy content in the F30 diet, and the nitrogen and phosphorus retention increased significantly. Fish fed the F30 diet revealed a higher incidence of sexual maturity. Fat content in cutlets and dressed carcasses were significantly affected by feeding rate but not by dietary fat level. Fish fed the F30 diet had more visceral fat and, consequently, lower dress-out percentage. Mortality, liver size and liver colour were not significantly affected by dietary fat level.
These experiments showed that even large differences in dietary fat level employed for the entire sea rearing period of Atlantic salmon, did not, or only marginally affected the cutlet and dressed carcass fat content. The high fat diet improved the feed utilization, thus decreasing the discharge to the environments. Furthermore, it resulted in greater growth at ad libitum feeding.  相似文献   

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