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12.
[目的]分析枣汁贮藏过程中HMF含量与颜色参数的相关性,得到表征大枣浓缩汁贮藏期间的颜色变化情况的各个参数之间的关系.[方法]在4、26和37℃条件下对大枣浓缩汁进行了7个月的贮藏研究,对产品中与非酶褐变颜色参数(A420、L’、Chroma值)与大枣浓缩汁中HMF含量变化的相关性进行了研究.[结果]试验表明,4、26和37℃贮藏条件下,大枣浓缩汁中的HMF和A420变化呈线性关系,颜色参教(A420、L*、Chroma值)是HMF的函数,具有相关性,可用一级动力学方程表示.26、37℃贮藏过程中大枣浓缩汁的颜色参数变化显著(P<0.05),明显高于4℃贮藏,低温有利于大枣浓缩汁的贮藏.[结论]试验可为研究大枣浓缩汁的贮藏品质提供一定的理论依据. 相似文献
13.
果汁加工过程中,为延长超滤有效运行时间,以富士苹果、秦冠苹果为材料,研究了酶解工序中使用复合纤维素酶对超滤通量和有效运行时间的影响,并进行了产业化应用。结果表明:添加复合纤维素酶,降低了酶解罐和超滤潴留罐中不溶物的含量,提高了超滤通量,延长了超滤运行时间,且对浓缩苹果汁的可溶性固形物含量、色值、浊度等品质指标没有影响;复合纤维素酶适宜的添加量为30~100mL/t;经过产业化应用发现,采用该技术,加工成熟度较大的苹果,超滤运行时间从13~16h延长到20~24h,超滤每周期有效运行时间提高45%以上,且平均通量比正常工艺提高10%以上。 相似文献
14.
Effect of high inclusion of rendered animal by‐product ingredients on growth,digestibility and economic performances in climbing perch Anabas testudineus 下载免费PDF全文
Md Sakhawat Hossain Md Abdul Kader Tanwi Dey Nadia Mahjabin Sony Mahbuba Bulbul Shunsuke Koshio 《Aquaculture Research》2017,48(3):931-940
A 70‐day growth trail was conducted to investigate the effects of inclusion of high levels of meat and bone meal (MBM) and protein concentrate (PC) on growth, digestibility and economic performances of climbing perch, Anabas testudineus. Four isonitrogenous diets were formulated by lowering the level of dietary fishmeal protein at 0 (D1, control), 70 (D2), 85 (D3) and 100% (D4) with a mixture of MBM and PC protein (1:1). Triplicate groups of 300 fish (mean weight of 0.80 g) stocked in each 40 m2 pond and fed the respective test diets. A digestibility trial was conducted after the growth trial in indoor glass aquarium. The result showed that growth parameters were significantly decreased (P < 0.05) with fishmeal replacement levels. However, significant differences were not found in feed conversion ratio and survival of fish. No difference was also found in protein efficiency ratio among D1, D2 and D3. Similar to growth parameters, total fish production was highest in D1, intermediate in D2 and D3; and lowest in D4. Apparent digestibility coefficients of dry matter, protein and lipid were highest (P < 0.05) in D1 and lowest in D4. The economic analysis revealed that the benefit cost ratio was ranked by D3 (1.81), D2 (1.71), D1 (1.66) and D4 (1.46) respectively. Upon considering the overall performances and unavailability of finite protein sources, it can be concluded that 70–85% fishmeal could be replaced with a mixture of MBM and PC (1:1) in practical diets for climbing perch. 相似文献
15.
The effects of setting time, whey protein concentrate (WPC), and calcium chloride (CaCl2) on textural properties of silver carp surimi were investigated. Response surface methodology was used to evaluate and compare the effects of setting time (30–90 min), WPC (1–9% of protein ratio), and CaCl2 (1–59 mmol/kg) on the gel strength. Models for breaking force, breaking distance, and gel strength of surimi gel were established. The maximum gel strength was achieved at the setting time of 60 min, WPC and CaCl2 at 5% protein ratio, and 15–18 mmol/kg. CaCl2 was the most significant factor affecting the gel strength. 相似文献
16.
Soy protein concentrate as a substitute for fish meal in diets for juvenile Acanthopagrus schlegelii: effects on growth,phosphorus discharge and digestive enzyme activity 下载免费PDF全文
Hameeda Kalhoro Jing Zhou Ying Hua Wing‐Keong Ng Lian Ye Jinzhi Zhang Qingjun Shao 《Aquaculture Research》2018,49(5):1896-1906
The current high demand and cost of fish meal (FM) necessities the evaluation of alternative plant protein ingredients in diets of farmed marine fish. A 56‐day feeding trial was performed to study the effects of replacement of FM with soy protein concentrate (SPC) in diets of Acanthopagrus schlegelii. Diets were prepared at levels of 0%, 30%, 47.5%, 65%, 82.5% and 100% SPC, respectively, replacing FM. The results indicated no significant differences (p > .05) in % weight gain (WG) and specific growth rate of fish fed S30% to S82.5% diets compared with the control diet while, further inclusion at 100% significantly depressed growth performance. SPC inclusion and phytase supplementation significantly affected the phosphorous discharge (P‐load) showing lowest value (3.83 ± 0.53 g/kg WG) in S100% compared to control (14.79 ± 0.37 g/kg WG) and in fish fed S30% diet (13.24 ± 0.89 g/kg WG) (p < .05). The results of this study showed that FM could be substituted up to 82.5% by SPC in the diet of Acanthopagrus schlegelii fingerlings (5.53 ± 0.12 g) without any adverse effects. Phytase supplementation SPC based diets could be effective in reducing the phosphorus load in the aquatic culture environment. 相似文献
17.
《Communications in Soil Science and Plant Analysis》2012,43(1):73-85
Separation of livestock slurries followed by reverse osmosis yields mineral concentrates (MCs) in which almost all nitrogen (N) is ammonium (NH4)-N. The ability of MCs to substitute calcium ammonium nitrate (CAN), a common conventional mineral N fertilizer, was tested in two trials on a silty loam soil (ware potatoes, 2009 and 2010) and four trials on sandy soils (starch potatoes, 2009 and 2010; silage maize in 2010 and 2011). The N fertilizer replacement value (NFRV) of spring-injected MCs ranged from 72 to 84%, slightly less than their share of ammonium-N (90–100%). The fate of N that was apparently unavailable to crops was not fully disclosed, but there were indications that ammonia loss may have played a role. 相似文献
18.
王伟 《青海畜牧兽医杂志》2012,42(6):12-13
两个月的试验结果表明,补饲精料对减少牦牛冷季掉膘有明显作用。8月龄牦牛补饲精料试验组比对照组少减重2.81kg,两者之间存在极显著差异(P<0.01)。20月龄补饲精料牦牛试验组比对照组少重2.19kg,两者之间存在极显著差异(P<0.01)。通过计算投产比得出,补饲精料是增加三江源区牦牛冷季营养供给,减少掉膘,提高生产效率的有效途径。 相似文献
19.
亚硝酸盐中毒(Nitrite poisonig)是畜禽常发生的一种中毒病。用白菜等含硝酸盐较多的菜类作猪的饲料,因调制加工不合理,会产生大量的亚硝酸盐,喂后引起猪急性中毒,常来不急抢救而死亡,对养猪业危害较大。用食用醋精加入调制白菜的浸泡液中,使其pH值为4时,完全可抑制反硝化细菌的活动,基本上不会产生亚硝酸盐。这是因为醋酸是含有2个碳原子的有机酸,对反硝化细菌毒性大,使菌体内DNA和ATP受到破坏,细菌失去脱氮作用所致。用醋精作调制白菜的抑制剂,会起到预防畜禽亚硝盐中毒的作用。 相似文献
20.
The effect of rolled canola seeds (RCS, 0% or 20% of the dry matter (DM) of the concentrate) combined with percentage of concentrate (45% (L) vs. 65% (H) of the diet DM) on rumen fermentation characteristics, production parameters and fatty acid (FA) profile of milk fat was studied in 20 entire goats and 12 goats fitted with ruminal and duodenal cannula. Goats were fed TMR ad libitum for 15 weeks with the final 12 weeks as the test period. Individual milk samples were taken in weeks 5 and 11 to determine the FA profile of milk fat. Feeding the H diets increased NEL intake, raw milk yield and yield of fat, protein and lactose. Feeding RCS increased fat corrected milk, milk fat content and fat yield. Combination of RCS and high percentage of concentrate increased fat corrected milk and fat yield. Milk protein content was not affected by dietary factors. Feeding the H diets increased the proportion of short-chain FA (C4:0–C8:0), each isomer of trans-C18:1 and c9,t11-C18:2 in milk at the expense of medium-chain FA with 11 to 17 C units. Feeding RCS decreased the proportion of medium-chain FA with 10 to 17 C units in milk and it increased that of C18:0, all isomers of trans-C18:1, c9-C18:1 and c9,t11-C18:2. Goats fed the H diets, and those fed the RCS had lower c9-C18:1/C18:0 and c9,t11-C18:2/t11-C18:1 ratios. Combination of RCS and high percentage of concentrate produced the highest proportion of all isomers of trans-C18:1 and c9,t11-C18:2 in milk, with the highest variability among the four diets for these FA. This was possibly related to between-goats differences in ruminal fermentation and to individual difference in desaturase activity in the mammary gland. It is concluded that feeding a high-concentrate diet combined with rolled canola seeds had a synergistic effect on the milk production and fat yield without alteration in milk protein content in dairy goats. This combination also resulted in changes in FA profile that may differently affect the nutritional value of goat milk for human health. 相似文献