食品粉末颗粒间的相互作用及结块行为的研究进展

粉体结块现象是食品工业中普遍存在的实际问题。针对食品粉体结块现象进行了综述,阐述了粉末颗粒间的相互作用,介绍了食品粉末结块的测试方法,分析了食品粉末结块动力学行为与结块控制方法,提出食品粉末结块研究中需要跟踪粉末颗粒间桥联的演变过程,并总结传热传质模型对食品粉末结块行为的重要作用,旨在为食品粉末结块的有效控制提供参考。     

邱博合成无定形二氧化硅和硅酸盐作为助流剂和抗结剂广泛应用于粉末食物

精细研磨的合成无定形二氧化硅和硅酸盐有效地用于粉末食物中,以提高产品的流动性和抑制产品结块。根据食物颗粒之间流动性差或结块的情况,可通过颗粒间互相作用的最小化来解决。弄清了颗粒间自然的相互作用后,我们将会针对邱博二氧化硅和硅酸盐如何使食物颗粒间的相互作用达到最     

食品粉体颗粒流动性分形维测试法

食品粉体颗粒粒度分布分形维能很好的表征颗粒群粒度分布。本文通过建立适合于数字显微方法测定粉体颗粒粒度分布分形维数值的数学模型,探讨食品粉体流动参数与颗粒粒度分布分形维数值间的关系。结果表明:食品粉体颗粒粒度分布分形维数值可以用于表征食品粉体流动性,各流动性表征参数与粒度分布分形维数值间具有明显的相关关系。因此,可以采用粒度分布分形维数值作为食品粉体流动性能的评价指标。形成了可靠、简洁的食品粉体流动性能测试新方法。     

食品造粒

1．食品造粒的目的由粉末状的原料制成颗粒状成品的加工过程称之为造粒。通过造粒，可达到以下目的：①速溶性用粉状直接溶解，往往会出现粉体相互粘连，粉体粘着在容器上等缺陷，影响了食品的溶解度。而造粒后的食品，就可避免这些缺陷，并且不会象粉体那样易于飞扬。②外形美观③保存性粉末料因吸湿、揭变、结块等因素而影响食品的保存性，尤以吸湿引起食品变性的情况更为多见。通过造粒，可减少食品的表面积，降低吸湿速度，可有效改善因吸湿而引起的食品变性。④均一性在多成分粉末料混合的食品（如调味料）中，造粒可避免在生产和流通…     

基于DEM离散元建模技术的双轴桨叶式食品混合机运动仿真分析

目的：分析双轴桨叶式混合机内食品粉体颗粒的运动混合特性,优化验证混合机结构。方法：采用EDEM软件对3种不同尺寸的食品粉体颗粒按比例混合进行仿真,以后处理Bin Groups建立混合箱观察混合情况,并通过研究不同类型食品粉体之间的颗粒数量来进行评估。结果：在t=5 s时,3种粉体食品颗粒所对应的方格中颗粒数量还存在一定的差距,但是基本相差不大,3种粉体食品颗粒的混合程度已经很高;3种粉体食品颗粒之间的接触随时间的变化趋势大体上是相同的,随着时间的增加,各种粉体食品之间的接触数量也随之增加,待t=8 s之后,各种粉体食品颗粒之间的接触数量基本达到稳定值。结论：采用离散元法可以有效分析桨叶式混合机中粉体食品的混合情况。     

防止粉末食品结块的方法

本发明是对粉末酱油、粉末黄酱、奶粉、果汁粉以及对水溶解度高的食品添加剂(例如天然的抽提物粉、柠檬酸、苹果酸、酒石酸等)在制造、使用或贮存时改善其吸湿结块的方法。 上述粉末食品中都含有一定的水分,因此会发生起粒或结块,在计量分取必需量时,就     

粉末汤料结块原因分析和对策

粉末汤料结块原因分析和对策岑涛目前在市场上流通的方便面产品中，时常会发现一些厂家的粉末汤料包发生结块（板结）现象，特别是在高温高湿的夏季，这一现象更为突出，现对这一质量问题产生的原因做一简要分析，并提出相应的对策。一、粉末汤料“结块”的概念及对产品质...     

快速分散颗粒型黄原胶的应用研究

对粉末黄原胶通过造粒技术制备颗粒型黄原胶,该产品具有疏松多孔的颗粒结构,提高了黄原胶的分散性和溶解速度,解决了其在食品中应用时的结团问题。对比了快速分散颗粒型黄原胶与普通粉末黄原胶和速溶型黄原胶的溶解特性。结果表明:颗粒型黄原胶在水、10%蔗糖和2.5%盐溶液中的粘度释放速度显著快于粉末黄原胶,与速溶型产品相当,可以广泛应用于食品中,尤其适用于速溶食品。     

不同蓝莓品种结块特性的研究

蓝莓粉作为一种风味独特、营养丰富的保健型功能性食品,在国内得到快速的发展,而蓝莓粉在加工和贮藏过程中很容易结块而使品质变差,为避免和减轻蓝莓粉在储藏过程中的结块问题,实验探索了不同温度、湿度以及粒径大小等对蓝莓粉结块现象的影响,并对比了不同蓝莓品种中糖、酸的含量,筛选出了不易结块的蓝莓品种,确定了减少蓝莓粉结块的最佳方法。结果表明:蓝莓的结块强度与其糖、酸含量呈现正相关性,糖酸含量越低,蓝莓粉的结块强度越小。储藏温度、湿度、粒径大小也显著影响蓝莓粉的结块程度,当储藏温度小于15℃、湿度小于20%,粉碎粒径较大时,蓝莓不易发生结块现象,有利于蓝莓粉的储藏。     

砂糖结块原因的分析

我厂是砂糖生产厂，砂糖在贮存过程中常有结块现象发生，在其它一些糖厂都不同程度地存在此现象。表面上看，结块只是个物理现象，不能认为是变质，但是一些用户对此现象并不宽容，而且要求十分严格。由于砂糖的结块，给用户生产增加了负担，因而影响了砂糖在市场上的销售。因此可以说砂糖结块直接关系到企业的经济效益。白砂糖结块原因，不少文献都有过广泛的论述。普遍认为主要是砂糖水分高，装袋时温度高，颗粒小且不均匀，仓库环境和叠堆高等因素的影响。据实际观察，干燥的砂糖是难于结块的，而表面潮湿的砂糖，遇到气温急剧下降，产生…     

Caking of lactose: A critical review

BackgroundCaking is a recurrent problem in various industries, whether it occurs during the production, storage or transport of powders. Caked powder results in longer processing times and decreased product quality, leading to significant economic loss. Several caking mechanisms have been described in the literature. However, they are often difficult to take into account in an industrial context, given the many parameters which influence the overall caking phenomenon.Scope and approachThis review describes the three relevant caking mechanisms for food powders in general. Focussing on predominantly crystalline lactose powder, we discuss how each of these mechanisms can explain caking and be prevented in the industrial context. The second part of this paper presents a critical review of the methods used to characterise caking to date.Key findings and conclusionsThe presence of amorphous material and other impurities must be assessed in crystalline lactose powders, as they can trigger amorphous and humidity caking. Particle size distribution is another key parameter requiring control as it can encourage caking through enhancement of particle interactions. In general, preventing caking in food powders can only be achieved by a thorough understanding of the production process and storage conditions. Moreover, the characterisation of caking remains a challenge as most methods published in the literature do not fit the needs of the food industry. The real demand is for a reliable method to predict caking which would be rapid and easy enough to be applied to each batch for quality control.     

Flow Properties of Commonly Used Food Powders and Their Mixtures

The aim of this study was to get an insight on flow properties of five different food powders and their mixtures frequently used in industrial production of foodstuffs and in households. The studied food powders were flour, maize semolina, sugar, cocoa, and skim milk powder together with their mixtures. Based on cohesion index, samples were categorized as follows: easy flowing—sugar powder, skim milk powder, maize semolina, and mixture 3 (wheat flour and sugar powder); cohesive—flour and mixture 1 (wheat flour and maize semolina); very cohesive—mixture 4 (wheat flour, cocoa, and sugar powder), and extremely cohesive—cocoa powder and mixture 2 (cocoa, sugar, and skim milk powder). Based on powder flow speed dependency test, positive multiple correlations were found between four powder mixtures and their basic components at all speeds. Flour, maize semolina, and mixtures 1 and 3 did not show any susceptibility to caking, while sugar, skim milk powder, cocoa powder, and mixtures 2 and 4 showed an increasing cake height ratio indicating their susceptibility to caking.     

Glass transition and flowability/caking behaviour of maltodextrin DE 21

Maltodextrin DE 21 is a spray dried amorphous powder that is commonly used as an ingredient in the food industry. The powder or an ingredient mix containing the powder can form very strong cakes if exposed to certain consolidating pressures and climatic conditions. In particular, it was believed that the glass transition can influence its caking behaviour. Consequently, the focus of this study was to investigate the influence of exposing maltodextrin DE 21 powder to temperatures around its glass transition and to measure its flowability or cake strength using a ring shear tester. To enable this work, the influence of water content on the onset glass transition temperature was measured along with the sorption isotherm of the powder. The ring shear testing showed that the maltodextrin powder readily formed a very strong cake over time when it was exposed to temperatures that were at or above its onset glass transition temperature. Maintaining the powder temperature at 4 °C below its glass transition should prevent the powder from caking.     

Optimization of Maltodextrin and Tricalcium Phosphate for Producing Vacuum Dried Mango Powder

Drying of mango pulp into powder is a challenging operation, mainly due to the sticky issue of mango powder in the dryer and caking during handling and storage. To overcome the above problem, maltodextrin, MD (drying aid) and Tricalcium Phosphate, TCP (anti caking agent) were added to the mango pulp at three levels and vacuum dried. The dried powder was analysed for properties such as hygroscopicity, degree of caking, flowability and sticky point temperature. Factorial design of experiment was used to investigate the effect of MD and TCP on the mango powder properties. The amount of MD and TCP required to reduce powder stickiness and caking were optimized based on the powder properties. At the optimum amount of MD (0.527 kg per kg dry mango solid) and TCP (0.0167 kg per kg dry mango solid), the values of mango powder properties were: hygroscopicity = 6.4 %; degree of caking = 7.8%; flowability = 18.6 s; sticky point temperature = 47.4°C.     

Effects of anticaking agents and storage conditions on the moisture sorption,caking, and flowability of deliquescent ingredients

Deliquescent highly soluble crystalline ingredients are prone to caking and dissolution when they are stored above a certain relative humidity (RH) but exhibit minimal moisture adsorption below this RH. Anticaking agents are added to improve the flowability of powders and to prevent or reduce caking. The objective of this study was to determine the effects of anticaking agents on the moisture sorption behavior, flowability, and caking characteristics of deliquescent ingredients and blends thereof. Single deliquescent food ingredients (sodium chloride, sucrose, fructose, and citric acid) and binary systems (sodium chloride blended with sucrose, fructose, or citric acid) were used as the host powders, and silicon dioxide, calcium silicate, and calcium stearate were the three anticaking agents studied. Moisture sorption isotherms were generated to investigate the water–solid interactions of the anticaking and host powders. Following controlled RH storage treatments, caking was assessed by the sieve test and flowability by avalanche power and avalanche angle measurements. Formulation had variable effects on deliquescence behavior and moisture sorption, while formulation, storage RH, length of storage, and RH cycling all significantly affected the physical stability of the powder blends. Calcium stearate was the most effective anticaking agent at reducing moisture sorption and delaying the onset of deliquescence, as well as maintaining the flowability properties of all powders tested. In particular, calcium stearate was able to substantially alter the moisture sorption behavior of blends of deliquescent ingredients, which are inherently more susceptible to the deleterious effects of moisture due to deliquescence lowering. The results are of great significance because they show that the effectiveness of an anticaking agent in preventing moisture-induced caking depends on the complexity of the host powders as well as on the interaction with environmental moisture. Thus, the type of anticaking agent added to a deliquescent ingredient must be tailored to the host powder to enhance product quality and stability.     

沙棘果渣对沙棘果粉的抗结块性能分析

沙棘果渣是由沙棘果汁生产加工过程中产生的副产品,具有较高的营养及利用价值。为了提高沙棘加工副产物的利用率,用沙棘榨汁后剩余的去籽果渣为原料,与纯沙棘果粉进行比较,研究沙棘果渣、抗结剂、果渣-抗结剂混合对沙棘果粉抗结的影响,以沙棘果粉结块率和流动性为指标,通过双指标加权法对沙棘果粉抗结条件进行综合评分。结果表明,沙棘果渣-抗结剂混合的抗结效果好,由单因素的试验结果,采用响应面软件分析,其最优条件以果渣粒度100目、果渣用量为14.50%、二氧化硅添加量为1.30%时,在此条件下沙棘果粉的休止角为47.55°、结块率为25.80%,其综合评分值为69.92分。说明,沙棘果渣-抗结剂混合能够较好的抑制沙棘果粉结块现象。本研究为进一步解决沙棘果粉结块的问题提供了思路。     

The contribution of milk fat towards the caking of dairy powders

Milk fat has a role in the caking of dairy powders during storage. The cohesiveness of six powders was studied by exposing the powders to temperature fluctuations whilst keeping the amorphous lactose component stable. It was found that caking was related to the amount of crystallised surface fat present on the powder. There was no measurable increase in the cohesiveness of the powders when only liquid fat bridging was present. An increase in cohesiveness was only found when the fatty liquid bridges were able to partially solidify due to a decrease in powder temperature. It is important to avoid elevated temperatures in bulk packed powders if the surface fat levels are above 13% (w/w), corresponding to a total fat content of 41% (w/w). Heating and subsequent cooling of such powders results in significant caking problems.     

预糊化时间对即食冲调米粉品质的影响

以碎米为主要原料,采用湿热方法对原料进行预糊化,再应用滚筒干燥制备成即食冲调米粉,通过分析即食冲调米粉的吸水性指数、水溶性指数、流变特性、微观结构、消化特性,研究预糊化时间对样品的影响.结果表明:预糊化处理后的米粉冲调特性和消化性质得到显著改善,相对于未进行预糊化处理组样品,经过30min预糊化后,吸水性指数和水溶性指...     

Influence of particle size on the physicochemical properties and stickiness of dairy powders

The compositional and physicochemical properties of different whey permeate (WPP), demineralised whey (DWP) and skim milk powder (SMP) size fractions were investigated. Bulk composition of WPP and DWP was significantly (P < 0.05) influenced by powder particle size; smaller particles had higher protein and lower lactose contents. Microscopic observations showed that WPP and DWP contained both larger lactose crystals and smaller amorphous particles. Bulk composition of SMP did not vary with particle size. Surface composition of the smallest SMP fraction (<75 μm) showed significantly lower protein (−9%) and higher fat (+5%) coverage compared with non-fractionated powders. For all powders, smaller particles were more susceptible to sticking. Hygroscopicity of SMP was not affected by particle size; hygroscopicity of semi-crystalline powders was inversely related to particle size. This study provides insights into differences between size fractions of dairy powders, which can potentially impact the sticking/caking behaviour of fine particles during processing.     

Glass transition and caking of spray-dried lactose

Simple test methods to determine the onset temperatures of viscous flow and caking of spray-dried amorphous lactose are described. The extent of viscous flow was measured as an increase in the density of lactose plugs within a cylindrical aluminium compaction apparatus after incubation for 3h at a specified temperature. Caking was characterized by an increase in the hardness of the lactose plugs formed. The onset temperature of viscous flow decreased with increasing water activity, A_w, and corresponded to the onset temperature of glass transition, T_g1. Glass transition temperatures were determined using both differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR) spin relaxation. The results suggest that elevation of the powder temperature above T_g1 promotes viscous flow and increases the potential for caking of amorphous food powders.