Quality of Reduced-Fat Frankfurter Modified by Konjac–Starch Mixed Gels

ABSTRACT:  Konjac–potato starch mixed gels were incorporated into reduced-fat (18%) frankfurters and compared with reduced-fat (18% fat, C18) and high-fat (28% fat, C28) controls for textural, sensory properties, and storage stability. At the same konjac concentration, increasing starch level resulted in lower G' (storage modulus) and G" (loss modulus) of the konjac–potato starch mixtures leading to more elastic-mixed gels. No differences in textural hardness among gel-added treatments were noticed. C28 had the lowest sensory firmness and highest juiciness scores. C18 and gel-added treatments had similar juiciness and firmness scores, and all treatments did not differ in overall acceptability.     

Influence of pH and added gums on the properties of konjac flour gels

The gel strength and texture of konjac gel and mixed gels of konjac and various gums were measured after gelation at various concentrations of alkali. A selection of different alkaline reagents was used. Regardless of alkali concentration, increasing konjac levels caused a decrease in pH but an increase in hardness and strength of konjac/gellan gum mixed gels. The highest gel strength and hardness were given by mixed konjac/gellan gum gels using sodium carbonate as the gelling medium. Under similar gelling conditions, the addition of gellan gum resulted in the greatest gel hardness. Of the gums examined, a possible synergistic effect on konjac/gellan gum mixed gel texture was observed.     

基于主成分分析构建混合多糖凝胶品质综合评价模型

为了构建混合多糖凝胶的综合评价预测模型,该研究采用全质构分析法（TPA）和感官评价法对5种亲水胶体复配得到的25种混合多糖凝胶进行测定。结果表明,混合凝胶质构硬度与感官硬度、脆性呈极显著正相关;质构内聚性、咀嚼性与感官硬度、脆性、咀嚼性、弹性、总体可接受度呈极显著正相关;质构弹性与感官弹性、咀嚼性呈极显著正相关,而感官气味与质构指标均不相关。利用主成分分析法从混合凝胶的11个评价指标中提取出3个主成分,累计方差贡献率达到82.45%,建立了混合多糖凝胶的综合评价模型。根据综合评分结果知,当混合凝胶配方为k-卡拉胶0.8%、魔芋胶1.2%、低酰结冷胶0.4%、刺槐豆胶0.6%、海藻酸钠0.4%时,混合多糖凝胶的得分最高为1 476.17;而当混合凝胶中不添加k-卡拉胶时,综合评分最低为424.56。基于主成分分析得到的综合评价模型对混合多糖凝胶品质进行评价,可以客观的反映出混合多糖凝胶的品质。     

魔芋胶/瓜尔豆胶对猪肉脯品质的影响

本试验研究了魔芋胶与瓜尔豆胶的复配胶体对猪肉脯品质的影响,测定了感官、色差、质构、水分活度、含水量、pH值这六个指标。结果表明:胶体组感官得分均高于空白组,添加0.24%魔芋胶与0.16%瓜尔豆胶的实验组的感官综合得分最高;单独胶体和复配胶的加入均在一定程度上改善了猪肉脯的色泽与质构特性,添加0.24%魔芋胶与0.16%瓜尔豆胶对猪肉脯质构特性的改善最为显著;胶体组猪肉脯水分活度显著降低,含水量显著增大(p0.05),添加0.24%魔芋胶与0.16%瓜尔豆胶的猪肉脯的水分活度最低,仅添加0.4%魔芋胶的猪肉脯的含水量最高;复配胶的可在一定程度上提高猪肉脯的pH值,且随着魔芋胶在复配胶中所占比例的增大,pH值也随之升高。总之,复配胶的加入可改善猪肉脯的感官品质、质构特性及耐贮藏性,添加含0.24%魔芋胶与0.16%瓜尔豆胶的复配胶较利于猪肉脯综合品质的改善。     

黄原胶和魔芋胶抑制碱诱导鸭蛋清凝胶的高温液化

本研究分别将黄原胶和魔芋胶添加至鸭蛋清中制备碱诱导凝胶,以探究亲水胶体对凝胶高温液化的抑制作用,结果表明:与对照组相比,添加亲水胶后的蛋清凝胶黏度、储能模量和损耗模量增大明显(p<0.05),褐变强度增加了7.99%和33.21%;当黄原胶和魔芋胶的浓度由0.50%增加至1.50%,凝胶硬度值提高49.60%和119.56%,穿刺强度提高20.59%和78.42%,持水性提高1.02%和9.47%,且添加黄原胶的蛋清凝胶硬度、穿刺强度和持水性均显著大于魔芋胶(p<0.05)。两种胶的浓度均为1.00%时,蛋清凝胶的感官评分最高。两种亲水胶的加入会改变蛋白质的二级结构及凝胶内部的分子间作用力:黄原胶量的增加显著降低了离子相互作用(p<0.05),无规则卷曲减少了41.23%,α-螺旋增加了81.29%;魔芋胶量的增加显著降低了疏水相互作用(p<0.05),β-折叠减少了34.97%,无规则卷曲和α-螺旋分别增加了68.97%和70.37%;氢键和二硫键均随两种胶浓度的增加而增强。综上所述,添加黄原胶和魔芋胶均能抑制碱诱导蛋清凝胶在高温处理过程中的液化现象,且加入黄原胶所形成的凝胶质构特性和持水性优于魔芋胶,而魔芋胶对于凝胶褐变强度的影响大于黄原胶。     

结冷胶对猪肉糜凝胶特性的影响

结冷胶作为脂肪替代物可有效降低猪肉糜中的脂肪含量,对增强低脂肉糜制品品质具有良好作用。本试验将结冷胶与水混合制备结冷胶胶体,研究结冷胶胶体替代猪背膘对猪肉糜凝胶特性及品质的影响。结果表明:添加结冷胶胶体显著影响(p<0.05)猪肉糜的蒸煮得率、色泽、质构、流变性和感官特性。结冷胶胶体添加量为0、0.3%和0.5%(质量分数)时,猪肉糜的蒸煮得率和质构差异不显著(p>0.05),0.7%时,蒸煮得率、L*值、硬度、弹性、内聚性和咀嚼性显著降低(p<0.05)。初始储能模量(G')随着结冷胶胶体添加量的增加而降低;结冷胶胶体添加量为0、0.3%和0.5%猪肉糜80 ℃时的G'差异不显著(p>0.05),结冷胶胶体添加量为0.7%时,G'显著下降(p<0.05)。综上所述,结冷胶胶体添加量为0.3%、0.5%时可降低猪肉糜中猪背膘的添加量。     

甜味料和亲水胶体对酸改性淀粉凝胶粘度及质构的影响

本文研究了各种甜味料(蔗糖、淀粉糖浆、山梨糖醇、麦芽糖醇、异麦芽糖醇)和亲水胶体(魔芋胶、琼脂、结冷胶、海藻酸钠、罗望子胶、果胶、阿拉伯胶、卡拉胶)对酸改性淀粉糊的粘度、凝胶体强度、质构的影响.结果表明:相同浓度甜味料和不同浓度(0.1％～0.5％)的胶体对酸改性淀粉协同增粘作用的大小顺序分别为:山梨糖醇＞异麦芽糖醇＞...     

Physicochemical and textural properties of ultrasound-degraded konjac flour and their influences on the quality of low-fat Chinese-style sausage

Physical and textural properties of varying molecular-weight konjac gels made by ultrasonic degradation were compared and gels were processed into low-fat Chinese-style sausages for the evaluation of textural and sensory characteristics. Results showed that as molecular weights decreased, storage modulus and loss modulus of konjac gels of varying molecular weights declined, indicating more elastic and viscous konjac gels. Shear values and textural springiness and cohesiveness of Chinese sausage were similar among all treatments. All treatments were found to have similar juiciness and overall acceptability scores. Results indicated that konjac gels with varying molecular weights could be used to partially replace pork fat to achieve similar textural properties. Incorporation of konjac gels with varying molecular weights at the current levels showed similar textural and sensory quality characteristics to the high-fat control, and contained less fat than traditional Chinese sausage.     

魔芋胶-黄原胶复配体系流变学特性及其凝胶形成动力学分析

为探究魔芋胶与黄原胶2 种食品胶复配使用后的协同作用,以魔芋胶和黄原胶为原料,控制总凝胶质量分 数为1%,以魔芋胶与黄原胶质量比分别为2∶8、4∶6、5∶5、6∶4、8∶2进行复配后,考察复配体系的流变学特性并对 其凝胶形成进行动力学分析。结果表明：魔芋胶-黄原胶复配体系具有假塑性,当魔芋胶的添加比例逐渐增大时, 复配体系黏度系数K增大,流体系数n减小,且复配体系的动态黏弹性质也随着魔芋胶与黄原胶的质量比不同而改 变,当魔芋胶与黄原胶质量比为6∶4时,复配体系的K值达到最大、n值最小,具有最强的假塑性及黏弹性。同时, 魔芋胶与黄原胶的不同质量比对凝胶形成速率有较大影响,当质量比小于6∶4时,凝胶形成显示出较慢的速率,且 形成的凝胶强度较弱;当质量比为6∶4时凝胶形成速率加快,SDRa曲线和G’曲线上升明显,形成的凝胶强度增大, 当质量比继续增加时,凝胶形成速率反而降低。采用阿伦尼乌斯方程对凝胶形成过程中的动力学参数进行拟合,决 定系数均在0.98以上,表现出较高的拟合精度;凝胶形成过程中的活化能在魔芋胶与黄原胶质量比为6∶4时有显著 增加（P＜0.05）,高温段与低温段间的活化能也表现出明显差异。     

亲水胶体对小麦玉米混合粉及馒头品质的影响

以玉米粉和小麦粉为原料,研究了黄原胶、瓜尔豆胶、羧甲基纤维素钠、魔芋胶4种亲水胶体不同的添加量(0.5%、1%、1.5%、2%)对混合粉粉质特性(吸水率、面团形成时间、稳定时间、弱化度)和小麦玉米混合粉馒头品质(比容、硬度、弹性、感官评分)的影响。用粉质仪测定混合粉的粉质特性,用体积测定仪测定小麦玉米混合粉馒头的比容,用质构仪测定小麦玉米混合粉馒头的硬度和弹性。结果表明:四种胶体均能增大混合粉的吸水率、面团形成时间、稳定时间,降低弱化度,但有一定的差异。黄原胶对粉质特性的影响最显著,然而添加了黄原胶的小麦玉米混合粉馒头品质较差。添加适量的瓜尔豆胶、羧甲基纤维素钠、魔芋胶可改善小麦玉米混合粉馒头的品质。其中,2%魔芋胶的比容最大,0.5%魔芋胶的硬度最小,2%羧甲基纤维素钠的弹性最大,感官评分最高。     

Compressive textural attributes, opacity and syneresis of gels prepared from gellan, agar and their mixtures

Gellan, agar and their mixed gels at an equal proportion of both were subjected to uniaxial compression to determine the textural attributes including fracture characteristics, opacity and syneresis. An increase in concentration of hydrocolloids increased opacity but decreased syneresis. Highly transparent gellan gels with opacity less than 8% were obtained; opacity of agar gels was highest, and was between 5% and 30% for their mixed gels. Syneresis as low as 1.5% was observed with the mixed gel containing 2% each of agar and gellan. The maximum stress and energy for compression increased with the level of gelling agents while instantaneous relaxation in height decreased. Binary combinations or mixed gels containing agar and gellan can provide unique textural and physical characteristics like syneresis and opacity.     

低酰基结冷胶酸性凝胶的凝胶特性

以葡萄糖酸-δ-内酯(glucono-δ-lactone,GDL)作为酸诱导剂,制备低酰基结冷胶(low acyl gellan gum,LA)酸性凝胶,考察基体质量浓度、GDL/LA复配比例以及酸液浸泡对酸性凝胶凝胶特性的影响。研究结果表明,GDL酸化为缓慢酸化,GDL/LA复配比例越高、体系的pH值越低,酸化速率越快。基体质量浓度和GDL/LA复配比例对酸性凝胶结构影响显著,断裂应力和保水性随着GDL/LA复配比例的增大先升高后降低。基体质量浓度越高,断裂应力和不透明性越大。GDL/LA复配比例增大,断裂应变减小,不透明性增大。当酸液pH值为1时,酸液浸泡对GDL/LA复配比例为2∶1和4∶1的酸性凝胶强度无影响,但GDL/LA复配比例为1∶4、1∶2和1∶1时,凝胶强度随浸泡时间的增加而增强,酸液浸泡可以促使酸性凝胶进行结构重建。     

辅料黏合剂的添加对调理猪排品质的影响

以猪颈背肉为主要原料,研究转谷氨酰胺酶(TG)、酪蛋白酸钠(SC)、复配胶(卡拉胶和魔芋胶1:1)对调理猪排品质的影响。通过单因素实验,研究转谷氨酰胺酶、酪蛋白酸钠、复配胶的添加对调理猪排剪切力、离心损失、蒸煮损失、水分含量、色差、出品率、感官评分的影响。在单因素实验的基础上,进行响应面试验,确定粘合剂的最优添加量。单因素结果表明,TG添加量为0.60%时,保水性及感官评分最高,酪蛋白酸钠添加量为0.10%,或复配胶(卡拉胶和魔芋胶1:1)添加量为0.20%时,既能保证适宜的嫩度与保水性,感官评分也最高。响应面试验结果表明,在转谷氨酰胺酶添加量为0.70%、酪蛋白酸钠添加量为0.07%、复配胶添加量为0.21%时,所加工的调理猪排的感官评分最高,总分60分时,得分为55.54。     

食用胶联合超声对鸡血豆腐凝胶物化性质、流变特性和体外消化率的影响

为研究复配食用胶联合超声处理对鸡血豆腐凝胶物化性质、流变特性及体外消化率的影响,结合前期实验结果,本实验选择瓜尔豆胶-阿拉伯胶(复配质量比3∶7)和瓜尔豆胶-魔芋胶(复配质量比5∶5)两种复配胶联合超声处理鸡血豆腐凝胶,并以产品出品率、粒径、Zeta电位、二级结构、凝胶流变性和体外消化率等为指标评价其品质.结果表明,添...     

Gellan gum/cassava starch mixtures in water systems and in milk systems

Cassava starch is an important ingredient in various foods. However, when processed, it develops some properties that are unsuitable for many industrial applications, such as unstable viscosity and excessive cohesiveness. To reduce those disadvantages, one alternative is a mixture of starch with hydrocolloids. The aim of this study was to evaluate the effect of 0:05, 0.1, 0.2, or 0.3% w/v gellan gum on the physical properties of pastes and gels of cassava starch in water and in milk systems. Differential scanning calorimetry (DSC), pasting properties, the texture profile, and the microstructure of gels were studied. The addition of gellan gum dispersions to the water system (WS) and the milk system (MS) gave rise to pastes with higher viscosity and, in the case of MS, with lower thermal and shear stability (higher breakdown). The addition of gellan gum had a greater textural effect on the MS, in which the addition of gellan at concentrations of 0.1 and 0.3% increased adhesiveness and decreased springiness of gels. Microscopy revealed a more uniform gel structure in the MS compared with the WS. Starch gelatinization temperatures were higher in MS than in WS.     

EFFECT OF ADDED SALT ON TEXTURAL PROPERTIES OF HEAT-INDUCED GELS MADE FROM GUM–PROTEIN MIXTURES

Large deformation rheological tests were employed to determine the textural differences in heat‐induced gel systems. Three different large deformation rheological methods (viscosity index and apparent elasticity, texture profile analysis (TPA) and torsional fracture) were employed to study the dependence of the ion type on the textural properties of heat‐induced mixed protein–gum gels. Protein–gum mixed solutions were prepared with bovine serum albumin (BSA) or egg white albumin (EWA) (20% w/v) with κ‐carrageenan (KCG), gellan (GLN) or xanthan gums (XNT) (0.5% w/v) at 0.1 M sodium chloride (NaCl), potassium chloride (KCl) or no added salt. Despite inherent differences in protein type, the main effect on the textural properties evaluated was for the kind of salt added, since potassium ions, with a strong influence on KCG and GLN gelation, affected the parameters related to the structure or hardness of the samples. There was no significant effect on parameters associated with sample ductility or elasticity. GLN formed stronger gels than KCG, whereas XNT did not perform as well in gel formation since it does not contribute to protein matrix formation. The results indicated that potassium may be substituted for sodium ions at low ionic strengths in foods where the incorporation of KCG or GLN helps to improve texture and related features.     

Corn Masa and Tortillas from Extruded Instant Corn Flour Containing Hydrocolloids and Lime

Extruded instant corn flour (EICF) samples with hydrocolloids (gums), such as gum arabic, carboxymethylcellulose (CMC), guar and xanthan and with different concentrations of lime (0.1, 0.2 and 0.3% w/w) were prepared by extrusion. The gums were added before or after thermal processing. The dehydration process followed through the weight loss (WL) in masa, the physicochemical (water absorption capacity (WAC) and WL during cooking) characteristics of masa were optimized to give longer dehydration times and tortillas with good textural (rollability, tensile strength and cutting force) properties. The lowest effective moisture diffusion coefficient (D*) was found in masa samples containing 0.2% (w/w) of lime and 0.5% (w/w) of the xanthan gum added before extrusion. These masas produce tortillas with optimum textural characteristics and highest yields.     

亲水性胶体对广式腊肠水分迁移及质构的影响

本文研究了卡拉胶、魔芋胶、瓜尔豆胶及其复配对广式腊肠烘烤过程中水分迁移、产品质构、感官等质量品质的影响。结果表明,广式腊肠添加亲水性胶体后,可略有提高产品的水分含量,尤其是瓜尔豆胶组(19.94%),比对照提高4.02%;在烘烤中期,亲水性胶体可降低广式腊肠的干燥速率,整体而言,亲水性胶体对烘烤过程中水分散失影响较小。胶体添加组感官得分除D3组,均高于对照组,其中添加复配卡拉胶与魔芋胶的感官综合得分最高,达到87.5;除瓜尔豆胶外,单独胶体和复配胶均能一定程度上改善广式腊肠的质构特性,尤其是复配胶体组。广式腊肠添加亲水性胶体后,复水率显著提高(p0.05),尤其是瓜尔豆胶及其复配组,达到3.79%。复配胶的加入可改善广式腊肠的感官品质、质构特性及复水性,不同亲水性胶体有不同的作用特点。     

食用胶对虾蛄中磷酸化肌原纤维蛋白凝胶特性的影响

将魔芋胶、卡拉胶、黄原胶分别添加到虾蛄磷酸化肌原纤维蛋白中,在不同食用胶、三聚磷酸钠添加量及不同温度下形成凝胶,研究食用胶对磷酸化蛋白凝胶特性的影响。结果表明：随着三聚磷酸钠添加量的增加,3 种食用胶形成的蛋白凝胶强度和保水性均提高;随着食用胶添加量的增加,卡拉胶与黄原胶形成的蛋白凝胶强度和保水性提高,魔芋胶添加量为0.1%时,其蛋白凝胶强度最高;随着温度的升高,魔芋胶与卡拉胶均对蛋白凝胶强度和保水性有显著性影响（P＜0.05）,但黄原胶对凝胶强度和保水性无显著影响（P＞0.05）。     

不同多糖对发酵空心挂面品质的影响

酵母发酵空心挂面是一种新型的工业化挂面产品,具有营养丰富、风味独特等特点,但尚存在干挂面韧性差和易断条、熟面条弹性不足等问题亟待解决。该文研究了瓜尔豆胶、黄原胶、海藻酸钠、羧甲基纤维素钠、魔芋粉5种常用多糖对发酵空心挂面微观结构、力学性质、蒸煮特性、质构品质和感官品质的影响。结果表明：与对照相比,单独添加0.1%瓜尔胶、海藻酸钠、羧甲基纤维素钠和魔芋粉时,挂面的蒸煮损失率从6.5%分别降低到5.8%、5.7%、5.3%和5.9%;添加0.5%黄原胶时,干挂面的面体更加致密,面条的最佳蒸煮时间增长了1.25 min,蒸煮损失减少了0.41%,干挂面的抗断裂强度和柔韧性、熟挂面的弹性、咀嚼性和拉断力分别提高了31.06%、49.79%、24.87%、61.62%和77.73%,此添加量下的面条的食用品质最佳,感官评价得分89分。5种多糖均显著改善了发酵空心挂面的柔韧性,及煮后挂面的弹性、咀嚼性和拉伸特性,其中黄原胶对发酵空心挂面的微观结构、力学性质、蒸煮特性、质构品质和感官品质改良效果较好。