喷雾干燥法和复合凝聚法制备仔稚鱼微胶囊饲料的研究

采用喷雾干燥法和复合凝聚法制备仔稚鱼微胶囊饲料。喷雾干燥法选用的壁材分别为明胶、明胶和麦芽糊精的复合物(1∶1);复合凝聚法选用的壁材是明胶和阿拉伯胶的复合物(1∶1)。结果显示,喷雾干燥法、复合凝聚法制备的微胶囊饲料粒径较小,大部分小于178μm。扫描电镜显示喷雾干燥法有较好的包埋效果,明胶为壁材的微胶囊表面有褶皱,明胶和麦芽糊精为壁材的微胶囊表面有许多小孔;明胶和阿拉伯胶复合凝聚的微胶囊出现粘连,没有明显的包埋效果。壁材明胶、明胶和麦芽糊精复合物、明胶和阿拉伯胶复合物3种微胶囊的脂类包埋率分别为26.59%、18.07%、26.37%,于20℃在3.5%NaC l溶液中放置30 m in氮保留率分别为36.03%、24.93%、27.47%。喷雾干燥过程中包膜维生素C的保留率仅为20.51%。     

高蛋白质饲料制粒工艺参数研究

以高蛋白颗粒饲料为研究对象，从蛋白质的理化特性出发，分析了饲料加工过程影响颗粒质量的因素；并设计2因素旋转组合试验，得出调质器出料口混合料水分与温度、喂料速度二次回归模型。还分别研究了水分、温度对硬度的影响，温度对消化率的影响，以及水分对糊化度的影响。     

流化床制备大黄鱼仔稚幼体微胶囊饲料的应用研究

将基础饲料先制成球丸,用流化床制备乙基纤维素包衣的微胶囊饲料。微胶囊饲料粒径为150～840μm的达70%。微胶囊饲料的包含率和脂类包埋率分别为97.2%±1.7%、63.2%±3.7%,在35.0‰的NaCl溶液中浸泡20、40、60min,氮保留率分别为73.6%±2.6%、65.8%±3.5%、53.7%±4.2%。扫描电镜(SEM)观察微胶囊饲料表面为均匀光滑一致的包衣膜,形状规则且无粘连现象。将微胶囊饲料饲喂15日龄大黄鱼25d作为实验组,对照组饲喂冷藏桡足类。实验结束时,实验组大黄鱼鱼苗的成活率虽显著低于对照组,但体重大于对照组。     

关于饲料制粒工艺中要素的控制

对饲料制粒中颗粒的水分、调质的温度和时间 ,二次制粒技术及机器等因素的控制作了论述     

不同制粒工艺对饲料脂溶性维生素稳定性的影响规律研究

重点监测了不同调质温度下环模制粒和挤压膨化制粒过程中,不同加工环节饲料维生素A、D3、E活性的变化,评估调质温度和制粒工艺对饲料中脂溶性维生素稳定性的影响.试验采集混合后、调质后、制粒后和打包处的饲料样品,检测样品中的水分和维生素A、D3、E的含量.结果表明,调质温度和制粒工艺对饲料中脂溶性维生素活性有较大影响,饲料中维生素A、D3、E活性损失主要集中在调质和制粒阶段,随调质温度升高而增加,且挤压膨化制粒较环模制粒对饲料中维生素A、D3、E的破坏作用更大.     

广东饲料制粒工艺对微生物影响的调查研究

本试验随机抽取广东饲料厂６个制粒工艺,分别检测工艺参数,测定５个不同生产阶段处－调质前、调质后,冷却后和打包处样品的霉菌、细菌和酵母菌的含量。调查结果表明,调质可平均杀死饲料中７７．８９％的微生物,霉菌孢子、细菌孢子和酵母菌孢子的杀死率分别为９５．７０％,６４．９４％和９５．９８％。粉料经调质、制粒、冷却至成品,微生物平均减少９５．３８％,霉菌,细菌和酵母菌分别平均减少９７．９９％、９９．７８％和     

不同制粒工艺对饲料脂溶性维生素稳定性的影响规律研究

重点监测了不同调质温度下环模制粒和挤压膨化制粒过程中,不同加工环节饲料维生素A、D3、E活性的变化,评估调质温度和制粒工艺对饲料中脂溶性维生素稳定性的影响。试验采集混合后、调质后、制粒后和打包处的饲料样品,检测样品中的水分和维生素A、D3、E的含量。结果表明,调质温度和制粒工艺对饲料中脂溶性维生素活性有较大影响,饲料中维生素A、D3、E活性损失主要集中在调质和制粒阶段,随调质温度升高而增加,且挤压膨化制粒较环模制粒对饲料中维生素A、D3、E的破坏作用更大。     

近红外分析技术在流化床一步制粒工艺中水分控制的应用

目的 研究了近红外(near-infrared, NIR)光谱技术在监控流化床一步制粒过程中颗粒水分应用的可行性。方法 运用非接触式探头对制粒全过程扫描采集光谱。选取光谱采用4种不同的方法建立了4个水分预测模型; 分别使用4个模型对干燥终点的物料水分进行预测, 优选出最佳建模方法。结果 4个模型的决定系数(r2)全部大于95%, 均方根误差(RMSECV)全部小于0.25。水分平均误差小于0.13%, 水分最大误差0.19%, 工艺要求水分误差≤±0.5%。3种方式中, 同时满足“水分+温度”两者区间范围的终点物料水分与目标值的偏差最小。结论 本研究提出了一种新的“温度+水分”控制方法, 中间产品的水分和温度都满足工艺要求时判定为一步制粒工艺的干燥终点。将温度、水分、温度+水分, 3种方式作为干燥终点的判定条件, 该方法满足工艺要求。近红外分析技术能够准确预测流化床一步制粒过程中间产品的水分, 其与温度控制相结合作为干燥终点判定的方式, 优于单一干燥终点判定条件。本文提出了一种多变量控制流化床干燥终点的新思路。     

粉碎、制粒工艺对饲料营养成分和单胃动物生产性能的影响

配合饲料加工工艺流程主要包括原料的接收、初清、粉碎、配料、混合、制粒、膨化、成品称重打包等主要工段,各工段对配合饲料质量和动物的生产性能都有较大的影响。综述了工艺流程中粉碎、制粒2个关键环节对饲料营养价值的影响及对部分动物生产性能的影响。     

制粒工艺对饲料中β-葡聚糖酶及纤维素酶活性影响的研究

试验随机抽取饲料厂不同制粒工艺生产的饲料样品,检测5个不同生产阶段——调质前、调质后、制粒后、冷却后和打包处样品的β-葡聚糖酶、纤维素酶活性。通过对β-葡聚糖酶和纤维素酶的热稳定性进行研究的结果表明：随着调质温度的升高酶活性显著下降,在60℃调质温度下,耐高温型β-葡聚糖酶活和纤维素酶活保存率分别为91.30%和90.40%;在85℃调质温度下,β-葡聚糖酶活酶活和纤维素酶活保存率分别为36.70%和58.20%。      

明胶包衣对薄荷香精释放特性的影响

研究了以明胶及其乳状液作为包衣剂的性质对薄荷粉末香精释放特性的影响。以明胶及其乳状液为包衣剂对薄荷香精进行流化床包衣操作制备包衣颗粒,再利用气相色谱法测定包埋效率和释放特性作为衡量包衣质量的指标。结果显示,以明胶浓度10%,含油量占明胶质量20%的乳状液为包衣剂,制备的包衣颗粒质量较高,包埋效率为90.44%,释放率在11min达到60%。上述结果表明,明胶乳状液作为包衣剂对薄荷香精进行包衣操作能够提高薄荷香精的缓释性能。      

Effects of inlet air temperature and spray rate of coating solution on quality attributes of turmeric extract coated rice using top-spray fluidized bed coating technique

The addition of natural antioxidants onto white rice kernel can improve its functionality. Curcuminoids that present in turmeric rhizomes possess high antioxidant activity and heat stability. The objective of this study was to investigate the effects of inlet air temperatures and spray rates of turmeric extract solution on quality attributes of the turmeric extract coated rice (TCR) using the top-spray fluidized bed coating technique. The experimental results have shown that inlet air temperature and spray rate of coating solution strongly affected the final moisture content and percentage of fissured kernel of TCR. Almost all of TCR kernels in the bed cracked when their final moisture content was lower than 11.8% wet basis. However, the head coated rice yield of fissured TCR slightly decreased from that of white rice. The color of TCR was uniform over the entire surface. Texture of cooked TCR insignificantly changed from that of uncoated sample. Increasing spray rate provided higher both total phenolic content (TPC) and total antioxidant capacity (TAC) whilst increasing inlet temperature yielded lower TPC but it did not affect TAC. Retentions of TPC and TAC of TCR after cooking remained higher than 90%.     

鱼、虾饵料的加工技术(下)

详细介绍了鱼虾在不同生长期的生活习性和生理特性,阐述了各成长阶段鱼虾饵料的加工工艺与设备选择的要点,分析了影响鱼虾饵料质量的因素.     

Marine and farmed fish in the Polish market: Comparison of the nutritional value

The proximate composition and fatty acids profiles of the muscle tissues of nine fish species that are popular on the Polish market were examined. The nine studied fish species were: Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), oceanic fish imported from China (walleye pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The lowest lipid content (below 0.1%) was noted in the muscle tissues of Baltic cod and walleye pollock caught in the Pacific. The muscle tissue of walleye pollock also had the lowest protein content (12.2 ± 2.0%). The highest lipid content was noted in the muscle tissues of Baltic salmon (13.1 ± 2.4%). The highest percentage content of eicosapentaenoic (C20:5 n − 3 – EPA) and docosahexaenoic (C22:6 n − 3 – DHA) acids (over 40%) was noted in the fat extracted from the oceanic fish and Baltic cod. However, due to the low fat content, the concentrations of EPA + DHA in these fish species and in imported farmed fish expressed in mg/100 g of muscle tissues are the lowest and range on average from 24.8 ± 5.7 mg/100 g (sutchi catfish) to 207.4 ± 125.4 mg/100 g (sole). This is why the consumption of these fish species has no significant meaning for coronary heart disease prevention. Consumers with symptoms of cardiovascular diseases should include the following fish species, which have high concentrations of EPA + DHA: Baltic salmon (3807.2 ± 666.3 mg/100 g); Polish farmed trout (1804.0 ± 279.2 mg/100 g); and Baltic herring (940.9 ± 306.6 mg/100 g) in their diets. However, the consumption of Baltic salmon must be limited on account of the levels of persistent organic pollutants found in it.     

流化床气流超微粉碎协同超高压法提取赶黄草黄酮工艺优化及其保肝作用研究

目的 优化赶黄草黄酮的提取工艺,并对其保肝作用进行研究。方法 采用流化床气流超微粉碎协同超高压法提取赶黄草黄酮,通过单因素和响应面试验优化提取工艺参数。同时采用随机法把小鼠分为正常对照组、CCl4模型组、联苯双酯组和赶黄草黄酮低、中、高剂量组。除正常对照组外,其余5组注射0.1%的CCl4构建肝损伤小鼠模型。采用全自动生化仪测定小鼠血清中AST、ALT、LDH值和MDA含量,肝组织中GSH-Px和SOD活性。结果 最佳提取工艺条件为：溶剂倍数28、压力400 MPa、保压时间13 min,在此条件下,赶黄草黄酮得率为3.92%,此法的提取效果优于其他3种单一的提取方式。体外保肝试验结果表明：赶黄草黄酮能显著降低CCl4所致肝损伤小鼠血清中AST、ALT、LDH的值和MDA含量,提高小鼠肝组织中GSH-Px和SOD活性,表明赶黄草黄酮对CCl4所致肝损伤具有较好的保护作用。结论 该研究获得了赶黄草黄酮的最佳提取工艺,得到的食叶草黄酮具有较好的保肝作用。     

Restoration of EPA and DHA in rainbow trout (Oncorhynchus mykiss) using a finishing fish oil diet at two different water temperatures

Feeding fish a fish oil finishing diet (FOFD) after grow-out on vegetable oil diet is one strategy to restore eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels. We investigated restoration of EPA and DHA in rainbow trout fed a FOFD preceded by a grow-out period on 50% or 75% palm fatty acid distillate (PFAD) diets at optimal (15 °C) or elevated (20 °C) water temperatures. Using the FOFD restored EPA and DHA in fillet and whole carcass of fish previously fed either 50% PFAD diet from 85% to 98% or 75% PFAD from 66% to 93% of values obtained for fish fed FO diet throughout. Water temperature did not influence EPA and DHA restoration. Growing rainbow trout with diets where FO was replaced by either 50% or 75% PFAD followed by a FOFD reduced FO usage by around 30% and 44% at 15 °C, respectively, and 32% and 48% at 20 °C, respectively.