Study of the functionality of selected hydrocolloids and their blends with κ-carrageenan on storage quality of vanilla ice cream

In the present paper, the functionality of hydrocolloids related to the rheological, physical and sensory characteristics of ice cream mixes and frozen ice cream was studied. Carboxylmethylcellulose, guar gum, sodium alginate and xanthan gum were used as primary stabilizing agents, whereas κ-carrageenan as secondary. The hydrocolloid concentrations were 0.1 and 0.2% and the primary to secondary ratio was 9:1. The ice cream samples were stored under quiescent frozen conditions. Samples were taken after 4, 8 and 16 weeks of storage and examined for the functionality of the stabilizing systems.The addition of hydrocolloids significantly reinforced the shear thinning behavior, particularly in the case of sodium alginate, xanthan gum, and κ-carrageenan which was attributed to gelation phenomena. Sodium alginate attained the better stabilizing effect improving textural quality and acceptance of ice creams even after 16 weeks of storage, whereas the presence of κ-carrageenan found to be a crucial factor for the cryoprotection. Xanthan gum was also evaluated as an effective stabilizing agent, indicating that gelling hydrocolloids may remarkably amend ice cream shelf life.Moreover, principal components and cluster analysis of instrumental and sensory data furnished important information for the correlation of objective and sensory properties and discrimination of stabilizing systems based on quality criteria.     

Microscopic structure,viscoelastic behaviour and 3D printing potential of milk protein concentrate-hydrocolloid complex coacervates

To prepare a milk protein-enriched ink for extrusion-based 3D food printing, this study investigated the effects of a wide range of hydrocolloids on the microstructures, viscoelastic characteristics and 3D printing performance of milk protein concentrate (MPC). The distributions of hydrocolloids and milk protein in mixed coacervates were characterised by fluorescent covalent labelling and confocal laser scanning microscope (CLSM), and the microstructure of the coacervates was observed by scanning electron microscopy (SEM). In addition, the rheological properties of prepared protein coacervates, including steady shear test, dynamic oscillatory test, thixotropy and creep recovery were investigated. Meanwhile, Burger’s model was fitted to the creep behaviour to further study their viscoelastic properties. The results showed that κ-carrageenan, pectin, guar gum and sodium alginate significantly increased the zero-shear viscosity, thixotropy and solid-like behaviour while xanthan showed an opposite phenomenon. Results showed that the presence of hydrocolloids improved the 3D printability of MPC by forming a complex network between protein particles and hydrocolloids, and guar gum, pectin and κ-carrageenan better help maintain the deposited 3D structures of MPC ink than xanthan.     

Evaluation of the time-dependent stability of starch-hydrocolloid binary gels involving NMR relaxation time measurements

A novel, non-destructive method of evaluation of the time-dependent stability of starch gels and binary starch-non-starchy hydrocolloid gels is presented. The low-field NMR technique applied provided the following results. On storage at room temperature, binary potato starch gels with xanthan gum are more stable in time than gels with guar gum and κ-carrageenan. Xanthan and guar gums as well as κ-carrageenan are dispensable as stabilizers of stored potato starch gel and building the cassava gel structure lasted over 96 h. In the binary system with cassava starch, guar gum performed best regardless storage temperature. At room temperature, admixture of hydrocolloids to plain cornstarch gels resulted in remove of water molecules from the gel network. Stabilization of cornstarch gels with hydrocolloids was, practically, dispensable and even non-beneficial regardless storage temperature. None among tested hydrocolloids stabilized the oat starch gel. On cold storage, κ-carrageenan performed best.     

Thermal,microscopic, and quality properties of low-fat frankfurters and emulsions produced by addition of different hydrocolloids

This study involves investigation of the effects of addition of different hydrocolloids on the thermal, microscopic, and quality properties of low-fat meat emulsions and frankfurters. The emulsion stability of the samples containing 0.5% κ-carrageenan, λ-carrageenan or chitosan, and the 1% chitosan containing sample were lower than that of the control group. Thermal analyses showed three denaturation peaks for minced meat at 57.42 °C, 64.21 °C and 78.58 °C. While the denaturation temperature of myosin for the sample produced with 0.5% of κ-carrageenan was significantly lower, samples containing 1% κ-carrageenan and 0.5% λ-carrageenan were not significantly different than that of the control group. The thermal denaturation temperature of myosin for samples containing 1% λ-carrageenan, and for 0.5% and 1% guar gum, xanthan gum and chitosan was significantly higher than that of the control. The denaturation temperature of sarcoplasmic proteins and actin for samples with 1% κ- and λ-carrageenan and 0.5% chitosan, was higher than for the control, while for other samples it was not significantly different. The scanning electron microscopy images of the control group and samples produced with 0.5% and 1% λ-carrageenan, 0.5% and 1% guar gum, and 1% κ-carrageenan showed gel-like structures, whereas other samples did not. Sensory evaluations showed that addition of hydrocolloids and reduced fat content lowered acceptance of frankfurters. Results showed that both κ- and λ-carrageenan, especially at 0.5% were the most suitable hydrocolloids for production of low-fat frankfurters and xanthan gum was the least suitable since it did not form proper structure.     

Interactions of κ-carrageenan Plus Other Hydrocolloids in Fish Myosystem Gels

ABSTRACT: Mixtures of κ-carrageenan plus other hydrocolloids (locust bean, guar, xanthan, iota-carrageenan, sodium carboxymethylcellulose, and sodium alginate) were examined for their effects on the mechanical and water holding properties of heat-induced gels made from washed blue whiting mince. Gel structure and thermal behavior were also studied. No synergistic effect was detectable through functional properties except for the mixture of κ-carrageenan with locust bean gum. Light microscopy revealed that κ-carrageenan and xanthan mixed locally with locust bean at its rich domains. κ-carrageenan and xanthan presented interactions with the protein matrix, which were more discernible in the first case. Differential scanning calorimetry (DSC) revealed faint interactions for the mixtures of κ-carrageenan with locust bean and with xanthan, and weakly synergistic gelling effects between the last two hydrocolloids. The blend of κ-carrageenan with sodium alginate exhibited thermally strong synergistic interactions but no particular effects were induced on corresponding functional properties.     

四种常见亲水胶体对面团特性的影响研究

采用粉质仪、快速黏度分析仪和流变仪研究添加黄原胶、κ-卡拉胶、魔芋胶和瓜儿豆胶对小麦粉粉质特性、糊化特性及面团流变特性的影响.研究结果表明,亲水胶体可以提高小麦粉的黏度,改善面团的黏弹特性,不同亲水胶体的作用效果存在差异,添加质量分数1%的黄原胶和魔芋胶后小麦粉吸水率分别增大了4.9%和7.9%,添加质量分数1%黄原胶、κ-卡拉胶和瓜儿豆胶后小麦粉糊的糊化温度分别降低了21.35℃、18℃、14.7 ℃,添加黄原胶和瓜儿豆胶能够显著地提高面团的稳定性,而添加魔芋胶能够延缓淀粉的重结晶特性.     

Development of the structure of an imitation cheese with low protein content

The structure of an imitation cheese with low protein content was developed by replacing 80% of the rennet casein with waxy maize starch and κ-carrageenan in the formula. Starch was partially hydrolyzed by using a fungal α-amylase to provide meltability. Formulation studies were carried out to obtain meltability and textural properties of a hard cheese with high protein content in the developed cheese. Response surface method was used to determine the effects of α-amylase and κ-carrageenan on the physical properties of the cheese. Hardness, cohesiveness and springiness of the cheese were affected positively by κ-carrageenan and negatively by α-amylase. Square of the meltability scores was used to explain the effects of components on meltability of the cheese. Square of the meltability was affected positively by α-amylase and negatively by κ-carrageenan. A formula was determined by using multiple response optimization method that would provide hardness, cohesiveness and meltability in the developed cheese similar to those of the high protein counterpart used as targets. Results obtained from a trial cheese produced according to the determined formula confirmed that the values of physical properties estimated by the optimization can be achieved.     

海藻酸钠对小麦淀粉性质及馒头品质的影响

采用快速黏度计、差示扫描量热仪、动态流变仪、粉质仪等,研究了海藻酸钠(AG)对小麦淀粉(WS)糊化性质及馒头品质的影响。结果表明,AG显著影响WS性质,明显改善馒头品质。AG增加WS糊化难度,表现为起始糊化温度、峰值糊化温度升高,降低溶解度。促进WS溶胀,表现为提高峰值黏度、膨胀力、终止糊化温度和糊化焓升高。提高淀粉糊的稳定性,表现为衰减值、回生值和老化率降低。AG提高糊化后的WS在外力作用下的稳定性,有利于WS黏弹性凝胶的形成,且形成的凝胶更趋向于固体。AG提高小麦粉的加工品质,使面团吸水率、形成时间、稳定时间增加,跌落值降低。一定质量分数的AG可增大馒头比容、高径比,AG在馒头中的建议用量为小麦粉质量的0.05%~0.15%。     

Incorporation of several additives into gluten free breads: Effect on dough properties and bread quality

The objective of this work was to assess the effect of emulsifiers, hydrocolloids and enzymes on gluten-free dough rheology and thermal properties and bread quality, while relating dough properties parameters to bread technological quality. Breads were based on rice flour, cassava starch and full-fat active soy flour, with 65% or 75% (flour-starch basis) of water incorporation. Additives used were emulsifiers (diacetyl tartaric acid ester of monoglycerides – DATEM and sodium stearoyl lactylate – SSL), enzymes (glucose oxidase and α-amylase) and hydrocolloids (xanthan gum, carboxymethylcellulose, alginate and carrageenan). Results showed that additive incorporation modified dough behavior, evidenced by different calorimetric and rheological properties. Besides, the electrophoretic pattern of dough extracted proteins changed with glucose oxidase addition. These modifications resulted in breads with different characteristics, such as specific volume, firmness and firming rate, and crumb structure. Nonetheless, they did not necessarily show better quality parameters than the control bread. The control dough displayed good performance for obtaining gluten-free breads of acceptable volume, crumb structure and, principally, with lower hardening rate during storage. Contrary to widespread opinion, this work shows that the presence of additives is not essential for gluten-free bread production. This fact provides new perspectives to the gluten free market at the moment of selecting raw materials and technological parameters, reducing production costs and facilitating gluten free products development.     

温敏型胶体对玉米淀粉3D打印固化性能的影响

目的:利用温敏型胶体的相转变特性,辅助实现淀粉在打印过程中的成型固化,并揭示不同种类胶体-淀粉体系的固化性能变化规律。方法:将不同比例的温敏型胶体(低酰基结冷胶、明胶、κ-卡拉胶)与玉米淀粉进行复配并测定其流变性能,通过打印圆柱及空心球模型、测试产品力-位移曲线、温度扫描流变、全质构分析及微观结构观测评估体系可打印及固化性能。结果:结冷胶和卡拉胶在2%～4%添加量,明胶在0%～2%添加量时,体系具有适宜的流变性能及良好的可打印性能。添加4%结冷胶及4%卡拉胶的产品表现出显著的塑性,固化效果较好;添加明胶的打印产品无显著塑性,打印产品不固化。结冷胶-淀粉混合体系的固化温度在35～43℃之间;卡拉胶-淀粉混合体系的固化温度在30～40℃之间,随着胶体含量增加,固化温度上升,固化速度加快。而随着明胶含量增加,固化温度从25℃下降至20℃以下且固化速度减慢。4%低酰基结冷胶产品具有更致密的凝胶网络,硬度高于4%κ-卡拉胶产品。明胶对硬度、弹性都有削弱作用,但使粘附力大幅提高。结论:适宜含量的低酰基结冷胶和κ-卡拉胶能够实现淀粉的成型固化,且卡拉胶固化性能优于结冷胶,而明胶则无辅助固化能力。     

低糖南瓜馅料的配方优化研究

以南瓜、澄粉、木糖醇、花生油、糯米粉为原料,以黄原胶、海藻酸钠为辅料,制作低糖南瓜月饼馅料。通过单因素试验探讨木糖醇添加量、花生油添加量、澄粉添加量、熟糯米粉添加量对馅料感官评价的影响,利用响应面中心法则试验预测南瓜馅料的最佳配方。优化后的最佳配方为:木糖醇8.80%、花生油7.21%、澄粉8.95%、熟糯米粉2.15%、黄原胶0.4%、海藻酸钠0.2%。在此条件下馅料的总糖含量为17.4%,水分含量为35.17%,且口感具有弹性,黏牙感低,硬度适中。     

食盐及pH对亲水胶体-马铃薯原淀粉糊化特性的影响

为探讨食品成分等对亲水胶体-马铃薯淀粉糊化、凝胶及膨润性质的影响,利用快速黏度分析法、质构分析法、离心法等方法测定了食盐、酸、碱对不同种类的亲水胶体-马铃薯原淀粉复合体系糊化温度、峰值黏度、末值黏度、衰减值、凝胶硬度、溶解度、膨胀势及持水力等的影响。结果表明：亲水胶体的种类、食盐、酸碱等均显著影响亲水胶体-马铃薯淀粉复合体系的糊化、凝胶及膨润性质。与马铃薯淀粉相比,添加海藻酸钠、卡拉胶、黄原胶的马铃薯淀粉复合体系的热稳定性增强,但凝胶性减弱;除亚麻多糖外,添加其它亲水胶体均不同程度的导致马铃薯淀粉的膨胀势、持水力降低,但对溶解度无显著影响。与不添加食盐的对照样品相比,添加食盐后,复合体系的热稳定性增强,但凝胶硬度、膨胀势和持水力均显著降低。相同种类的亲水胶体,在碱性条件下比在酸性条件的热稳定性高。     

Long-term storage stability of selected potato starch – Non-starchy hydrocolloid binary gels

All 3, 4 and 5% potato starch gels containing either κ-carrageenan, guar gum or xanthan gum were prepared and their stability in terms of rheological and textural properties was checked on 30 day storage. It was shown that rheology of these binary potato starch – non-starchy hydrocolloid mixtures could be controlled by anionic character of the admixed hydrocolloid. Depending on the hydrocolloid added, gels made of the tuber starch can either retain their pattern typical for tuber starches or turn into that typical for gels of cereal starches. Hydrocolloids added plasticity to the binary gels but it was lost to a significant extent within the first day of storage. Resulting gels with dominating elastic character are rheologically and texturally fairly stable for subsequent 30 days of storage. Generally, hydrocolloids stabilized potato starch gel on long-time storage to the extent dependent on the gel concentration.     

亲水胶体对石蒜淀粉糊特性的影响

为改善石蒜淀粉的加工品质特性,系统研究亲水胶体对石蒜淀粉溶胀能力、糊化特性、冻融稳定性及流变特性的影响。添加亲水胶体后,石蒜淀粉膨胀力均有所下降,除魔芋胶外,混合体系的溶解度均有所提高;亲水胶体有效抑制了淀粉的回生,使冻融稳定性增强,其中黄原胶效果较明显。糊化性质表明亲水胶体的加入使峰值时间和成糊温度升高,峰值黏度、崩解值和回生值降低,提高了石蒜淀粉的热稳定性和冷稳定性。静态流变实验结果表明：Herschel-Bulkley方程能很好拟合稳态流变曲线,加入亲水性胶体后体系仍为典型的假塑性流体,除阿拉伯胶外,其他胶体的添加均不同程度地降低了淀粉凝胶的触变性。动态流变实验结果表明所有样品体系G’均大于G”,且呈现出频率依赖性,说明具有典型的弱凝胶特性。加入亲水胶体能保持淀粉体系内部结构稳定,增强其抗剪切性。因此,亲水胶体可以一定程度改善石蒜淀粉糊的性质,且与亲水胶体的种类、结构有关。     

黄原胶和瓜尔豆胶对小麦淀粉冻融稳定性的影响

将小麦淀粉分别与黄原胶和瓜尔豆胶以一定的比例复配,利用析水率实验、DSC方法和SEM微观结构观察等方法,研究亲水胶体黄原胶和瓜尔豆胶在5次冻融循环过程中对小麦淀粉稳定性的影响。研究结果表明:小麦淀粉的析水率随着循环次数的增加而增加,黄原胶和瓜尔豆胶能够明显降低冻融过程中小麦淀粉的析水率,从而抑制小麦淀粉冻融过程中的老化,且随着亲水胶体浓度的增加,对冻融稳定性的改善作用越强;小麦淀粉经过5次冻融循环后,淀粉胶基形成了大量的孔洞,并产生不连续丝状的,类似纤维的结构,且基质较薄,添加亲水胶体后显著改变了小麦淀粉的表观形态,孔洞明显减少,且淀粉基质增厚,形成了类似片状的网络结构。因此,黄原胶和瓜尔豆胶均能在一定程度上改善小麦淀粉的冻融稳定性,且与添加浓度有关。     

Formation of Maize Starch Gels Selectively Regulated by the Addition of Hydrocolloids

Native maize starches containing amylose are used for manufacturing gels in food technology at concentrations of about 7%. Depending on the pasting conditions chosen, several hours may be required for the final consistency to be attained. For this reason the influence of hydrocolloids was investigated with economic factors dictating an effective concentration of approximately 5% in terms of the pure starch. The gelation process was monitored quantitatively by means of rheomechanical oscillation measurements in the linear viscoelastic range. The substances investigated were polysaccharides with chemically similar structures and classified as safe under foodstuff regulations: guar gum, locust bean gum, x-carrageenan, t-carrageenan, xanthan and carboxymethylcellulose (CMC). The gelation process can be significantly accelerated by a range of hydrocolloids, with the effect decreasing as follows: CMC > locust bean gum > guar gum > x-carrageenan > xanthan. The mixtures achieved between 45% and 80% of the final gelation stability of pure starch of 100Pa. The gelation process is clearly retarded by the hydrocolloid t-carrageenan. With the aid of the rheological data it is possible to correlate the influence of the hydrocolloids on the process of self-aggregation and also on the resulting viscoelastic properties of the mixed gels with one another. In terms of a molecular interpretation it is possible to distinguish between exclusion effects and specific interactions in the functioning of the hydrocolloids.     

The influence of α-amylase supplementation, γ-irradiation (60Co) as well as long time of storage of wheat grain on flour technological properties

The varieties of winter wheat, Aria and Beta, were studied. The Aria variety was stored for the period of four years. The part of wheat grain from Beta variety was irradiated with γ rays (⁶⁰Co). In extracts from wheat kernels and flour protein content, total α- and β-amylolytic activity as well as α-amylolytic activity were determined. α-amylases of native and fungal origin were added to the flour obtained from samples of stored wheat kernels (Aria), irradiated and non-irradiated (Beta). Consequently native α-amylase activity of flour increased by 25 % and 50% respectively. Extensive technological estimation of grain and flour with amylase supplements was carried out. The study included: sedimentation analysis, falling number test, milling experiment, farinogram and extensogram analyses, measurement of the degree of damaged starch and flour colour, as well as baking experiment. The obtained experimental loaves of bread were tested for their ability to remain fresh. It was found out that the stored grain flour was characterized by the highest α -amylolytic activity and the lowest falling number value, whereas the irradiated grain flour showed the highest degree of starch damage and water absorption. When α-amylase supplementation to doughs wasn't accompanied either by irradiation or storage of grain, it definitely changed their physical properties for the worse. The negative influence of native α-amylases appeared to be less significant than that of fungal α-amylases. The positive influence of α-amylase supplementations, especially of those increasing by 25 % the native α-amylolytic activity of flour on volume, and freshness of loaves of bread was observed.     

Characterisation of flour, starch and fibre obtained from sweet potato (kumara) tubers, and their utilisation in biscuit production

Sweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico-chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven-fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.     

Influence of pH and hydrocolloids addition on yam (Dioscorea alata) starch pastes stability

Yam tubers (Dioscorea alata) are a non-traditional starch source that could be used as food ingredient. The stability of yam starch pastes (6/100 g suspension) submitted to different pH conditions during gelatinization and the effect of hydrocolloids addition (guar and xanthan gums) on starch syneresis under refrigeration were analyzed. Changes in pH (3, 5, 6) or the addition of gums (0.1–0.5/100 g suspension) did not affect the starch gelatinization temperature nor the gelatinization enthalpy as determined by differential scanning calorimetry. Rheological behavior was characterized by amylograph profiles and oscillatory rheometry. Amylograms showed that yam starch pastes maintained a high viscosity under heat treatment and mechanical stirring in neutral to slightly acidic conditions. Brabender viscosity increased when gums were added; the effect of guar gum on viscosity was more marked than that of xanthan gum. During refrigerated storage exudate production was observed of pastes without gums. Xanthan gum, at a concentration of 0.5/100 g suspension, showed higher effectiveness than guar gum to reduce exudate production during refrigerated storage. The addition of hydrocolloids could allow yam starch to be used in foods requiring low temperatures.     

Controlling rheology and structure of sweet potato starch noodles with high broccoli powder content by hydrocolloids

Incorporating high volume fractions of broccoli powder in starch noodle dough has a major effect on its shear modulus, as a result of significant swelling of the broccoli particles. Several hydrocolloids with distinct water binding capacity (locust bean gum (LBG), guar gum, konjac glucomannan (KG), hydroxypropyl methylcellulose (HPMC) and xanthan gum), were added to systems with 4 and 20% (v/v dry based) broccoli particles, and the effect of this addition on dough rheology, mechanical properties and structure of cooked noodles was investigated. Hydrocolloids with low (LBG and guar gum) and intermediate (KG) water binding capacity had no significant effect on shear rheology of the dough. Adding hydrocolloids with high water binding capacity (HPMC and xanthan gum) decreased the shear modulus of dough with 20% broccoli particles significantly. CLSM analysis of cooked noodles showed that in samples containing xanthan gum there was also an inhibition of swelling of starch granules. Strength and stiffness of cooked noodles with 20% broccoli particles were higher for samples containing xanthan gum, than samples without xanthan gum. The cooking loss and swelling index of samples with added hydrocolloids were slightly lower than samples without hydrocolloids. Our results showed that hydrocolloids with high water binding capacity can be used to control the degree of swelling of vegetable particles and starch granules in starch noodle products, and thereby control both dough rheology and textural properties of the cooked noodles.