Quality characteristics and consumer acceptance of yogurt fortified with date fiber

Yogurt is considered a healthy food and incorporating dietary fiber will make it even healthier. Date fiber (DF), a by-product of date syrup production, is a good source of dietary fiber. The effect of fortification with DF on fresh yogurt quality was investigated. Acidity, pH, color [L* (lightness), a* (redness), and b* (yellowness) values], texture profile, sensory properties, and consumer acceptance were studied. Control yogurt (without fiber), yogurt fortified with 1.5, 3.0, and 4.5% DF, and yogurt with 1.5% wheat bran (WB) were prepared. Fortification with DF did not cause significant changes in yogurt acidity, although pH was increased. Yogurts fortified with DF had firmer texture (higher hardness values) and darker color (lower L* and higher a*) compared with control or WB yogurts. Consumer test results indicated that the appearance, color, and flavor ratings were significantly affected by fiber fortification. Yogurt fortified with up to 3% DF had similar sourness, sweetness, firmness, smoothness, and overall acceptance ratings as the control yogurt. Sensory ratings and acceptability of yogurt decreased significantly when increasing DF to 4.5% or using 1.5% WB. Flavoring yogurt fortified with 4.5% DF with vanilla did not improve flavor or overall acceptance ratings. Thus, fortifying yogurt with 3% DF produced acceptable yogurt with beneficial health effects.     

Fortification of sweetened plain yogurt with insoluble dietary fiber

 Seven types of insoluble dietary fiber from five different sources (soy, rice, oat, corn and sugar beet) were used to fortify sweetened plain yogurt. Fiber addition caused an acceleration in the acidification rate of the experimental group yogurts, and most of the fortified yogurts also showed increases in their apparent viscosity. Soy I and sugar beet fibers caused a significant decrease in viscosity due to partial syneresis. In general, fiber addition led to lower overall flavor and texture scores. A grainy flavor and a gritty texture were intense in all fiber-fortified yogurts, except in those made with oat fiber. Oat II fiber gave the best results; differences with controls in terms of flavor quality scores not being statistically significant. The evolution of organic acids during the fermentation and cold storage of control and oat-II-fiber-fortified yogurts showed a similar pattern; only acetic and propionic acids were found in significantly higher amounts in the fiber- fortified product. Received: 27 June 1996/Revised version: 2 September 1996     

Fortification of sweetened plain yogurt with insoluble dietary fiber

 Seven types of insoluble dietary fiber from five different sources (soy, rice, oat, corn and sugar beet) were used to fortify sweetened plain yogurt. Fiber addition caused an acceleration in the acidification rate of the experimental group yogurts, and most of the fortified yogurts also showed increases in their apparent viscosity. Soy I and sugar beet fibers caused a significant decrease in viscosity due to partial syneresis. In general, fiber addition led to lower overall flavor and texture scores. A grainy flavor and a gritty texture were intense in all fiber-fortified yogurts, except in those made with oat fiber. Oat II fiber gave the best results; differences with controls in terms of flavor quality scores not being statistically significant. The evolution of organic acids during the fermentation and cold storage of control and oat-II-fiber-fortified yogurts showed a similar pattern; only acetic and propionic acids were found in significantly higher amounts in the fiber- fortified product. Received: 27 June 1996/Revised version: 2 September 1996     

不同来源膳食纤维的结构和理化性质分析

以鹰嘴豆膳食纤维(dietary fiber,DF)、葡萄DF、大豆DF和麦麸DF为试验原料,研究了4种不同来源DF的理化特性(持水力、持油力、膨胀力、粒径、溶解度、热特性)之间的差异,并用傅里叶变换红外光谱、扫描电镜表征其结构变化。结果表明:鹰嘴豆DF的持水力、持油力最高,分别为2.45,1.97 g/g;麦麸DF的膨胀力最好,为3.18 mL/g;4种膳食纤维的溶解度与温度呈正比,其中鹰嘴豆DF的溶解度最高;傅里叶变换红外光谱分析发现,4种 DF的红外吸收光谱基本相同,均含有C—H、O—H、C O、C—O—C键;热特性分析结果表明豆类DF有更高的变性温度,而麦麸DF的热稳定性最好。扫描电镜结果显示鹰嘴豆DF颗粒表面带有无规则褶皱,褶皱存在使DF表面积增大,从而表现出更高的持水力和持油力。综上,鹰嘴豆DF可以作为良好的保水保油剂,应用于肉制品、乳制品等食品加工,提升产品品质。     

苹果渣膳食纤维桃酥的研制

桃酥是中国传统的民间糕点食品,但因其高糖、高脂、高热量而与当代人的膳食结构不相适应。添加适量的苹果渣膳食纤维不仅满足生产工艺条件,而且从营养、风味及保健作用上都有很大的改善和提高,研制出一种低糖低脂保健桃酥。     

A new kind of dietetic bread enriched with dietary fiber

A new sort of dietetic bread has been developed with a 4-fold higher content of food cellulose fibers and a 25% lower fuel value. Such effect was achieved due to the use of qualitatively different sources of food fibers--wheat bran and methyl cellulose (MLI-100). The chemical composition of the new sort of bread has been presented and certain categories of patients have been specified who can use this bread in their diet.     

苹果渣SDF酸奶的研制

针对酸奶中缺乏膳食纤维的情况,阐述了在酸奶中添加苹果渣膳食纤维的必要性,研究了苹果渣中的可溶性膳食纤维(SDF)的含量情况,讨论了在酸奶中添加苹果渣SDF的量为4g/100g时,可以取得良好的效果。     

Production of soy yogurt enriched with glyceollins

Soy milk was prepared from regular soybean (M1), soybean germinated for 3 days at 25°C (M2), and soybean germinated under fungal infection (M3). Rhizopus microsporus var. oligosporus ATCC 22959 was used as the elicitor for glyceollin production. Each soy milk was fermented with Streptococcus infantarius 12 and Weissella sp. 4 (1:5, v/v) for 12 h at 37°C. Significant induction of glyceollins was confirmed only in M3 soy milk and glyceollins maintained stably during 12 h fermentation period. The concentration of glyceollins in M3 yogurt was 2,400.4±83 and 2,525.2±158 μg/g dry matter (d.m.) at 0 and 12 h, respectively. The amount of daidzein was significantly higher in M3 yogurt (635.1±21) than that of M1 (417±11) and M2 (545±17 μg/g d.m.) yogurt in 12 h (p<0.05). M2 yogurt had the highest amount of genistein (695.3±17) followed by M3 (634.5±26) and M1 (612.5±14 μg/g d.m.) yogurt. M3 soy yogurt also showed the highest content of total phenolic compounds (5.37 mg/g) and antioxidant activity. The results indicated that functional soy yogurt can be prepared from soybean enriched with glyceollins.     

麦麸膳食纤维火腿肠的研制与营养价值评价

根据食物有机搭配可改善制品的营养、感官和质构品质的基本原理,综合肉类食品及麦麸膳食纤维原料的特点,开展麦麸膳食纤维在火腿肠中的应用研究,试制出了新型麦麸膳食纤维复合火腿肠,其主配方中猪瘦肉占62.7%,麦麸粉占7.5%,淀粉占4.4%.麦麸膳食纤维的添加改善了火腿肠的功能特性,由于同时使用了低钠食盐,与普通型火腿肠相比,麦麸膳食纤维火腿肠的脂肪含量降低了50%、热量降低了20%,氯化钠含量也有所降低,符合清淡(light)食品的第一定义.试制出的复合火腿肠在外观、组织结构、色泽和风味上均可接受,具有良好的质构.为开发利用小麦加工副产品、研制健康功能型肉制品开辟了新途径.     

蓝靛果酒渣抗氧化膳食纤维酸奶的研制及性质分析

本研究以蓝靛果酒渣为原料,制备抗氧化性膳食纤维酸奶,并对其品质及抗氧化能力进行评价。实验结果表明:蓝靛果酒渣膳食纤维含量为63.32%,多酚含量27.01 mg/g,总黄酮含量42.82 mg/g,每克蓝靛果酒渣对DPPH自由基清除能力相当于1.89 g V_E,符合抗氧化膳食纤维标准。蓝靛果酒渣抗氧化膳食纤维酸奶的适宜工艺条件为蓝靛果酒渣1.0 g/100 g、白砂糖8 g/100 g、果胶0.1 g/100 g、脱脂奶粉1.0 g/100 g、发酵时间7 h。酒渣酸奶中多酚和黄酮的保留率分别为80.21%,84.34%。与对照酸奶相比酒渣酸奶的滴定酸度、持水率、乳清析出率、质构无显著变化(p>0.05),而酒渣酸奶对DPPH自由基清除能力、·OH自由基清除能力和总还原能力均显著高于对照酸奶(p<0.05)。蓝靛果酒渣适合作为抗氧化膳食纤维在乳品中应用。      

富含共轭亚油酸酸奶的特性分析

通过在脱脂乳中分别添加不同浓度的亚油酸进行发酵培养,测定发酵后酸奶的酸度、黏度、保水性、活菌数和共轭亚油酸含量,根据这些特征指标来确定亚油酸的最适添加量。结果表明,亚油酸添加量对酸奶的酸度和保水性影响较小,而酸奶的黏度、活菌数和共轭亚油酸的产量均与亚油酸添加量密切相关。当亚油酸添加量小于0.075%时,酸奶的黏度和活菌数随亚油酸添加量的增加而增加,而当亚油酸添加量大于0.075%时,酸奶的黏度和活菌数均逐渐降低。酸奶中共轭亚油酸的含量随亚油酸添加量的增加而增加,随发酵时间的延长呈现先增加后减少的趋势。综合所有结果后发现,当脱脂乳中亚油酸添加量为0.1%,发酵36 h时,酸奶的黏度为2 700 m Pa·s,酸度为80°T,保水性为45%,活菌数为4.0×108CFU/m L,共轭亚油酸含量达到0.9 mg/m L,可获得品质优良且富含共轭亚油酸的酸奶。     

Viscoelastic properties of orange fiber enriched yogurt as a function of fiber dose, size and thermal treatment

The effect of orange fiber addition on yogurt viscoelastic properties was studied, the following factors were evaluated: (i) fiber doses (0, 0.2, 0.4, 0.6, 0.8 and 1 g/100 ml) (ii) fiber particle size (0.417-0.7 and 0.701-0.991 mm) (iii) fiber addition prior or after pasteurization. (i) In yogurts with pasteurized fiber G′, G″ and complex viscosity increased with fiber dose, whereas in non-pasteurized fiber yogurts smaller fiber particles (<0.4 g/100 ml) rheological parameters decreased due to the disruptive effect of the fiber, and over 0.6 g/100 ml rheological parameters increased. The presence of particles alters yogurt structure but when the fiber dose is high enough the water absorption compensates the weakening effect of the fiber. (ii) G′, G″ and viscosity were higher in yogurts with large particles than in yogurts with fiber of smaller size. The higher the number of fiber particles, the higher the disrupting effect. (iii) Fiber pasteurization in the mix enhances its integration in the gel matrix.     

低脂菊苣膳食纤维凝固型酸奶的生产工艺

以菊苣膳食纤维和脱脂乳粉为原料,通过乳酸菌发酵生产一种低脂凝固型酸奶。通过单因素试验和均匀设计试验,初步确定最佳发酵工艺条件为:菊苣膳食纤维2.08%,脱脂乳粉12.7%,蔗糖7.06%,发酵剂接种量为0.8 g/L,发酵温度为42.8℃,发酵时间为7.5 h。     

浓缩鲜荔枝果汁乳酸菌饮料的研制

介绍了用鲜牛奶为原料经乳酸菌发酵后,加入浓缩鲜荔枝果汁配制而成的荔枝乳酸饮料的研制工艺。它具有较高营养价值和特殊的典型性风味,比牛奶更易为人体吸收,并具有良好的保健作用,很受消费者青睐。     

强化膳食纤维挤压膨化食品加工工艺的研究

以玉米和荞麦为主要原料,强化膳食纤维开发研制挤压膨化休闲食品,并对挤压工艺参数进行了优化。实验首先采用单因素法考察了不同含量的膳食纤维对产品口感的影响;然后采用Box-Behnken实验设计方法进行实验设计,依据所得的实验数据建立了膨化度(Y1)与物料湿度(X1)、机筒温度(X2)和螺杆转速(X3)的相关数学统计模型:Y1=0.119179 0.016455X1-0.018315X3 0.028592X12 0.027734X32;通过对实验数据进行响应面分析,确定了挤压工艺的最佳参数:物料湿度为12.7%,机筒温度为120℃,螺杆转速为274r/min。分析表明,不溶性膳食纤维经挤压蒸煮后降低了17.9%。     

不同类型亲水胶体对豆乳酸奶质构、流变学特性的影响

研究了5种不同类型亲水胶体包括中性多糖瓜尔豆胶(0. 01%～0. 1%)和刺槐豆胶(0. 01%～0. 1%)、蛋白类多糖明胶(0. 1%～1%)以及离子型多糖卡拉胶(0. 01%～0. 1%)和黄原胶(0. 001%～0. 01%)对豆乳酸奶的持水力、质构特性和流变特性的影响。结果显示,在持水力方面,明胶(≥0. 5%)的添加可显著增强豆乳酸奶的持水力达100%,中性多糖瓜尔豆胶的添加会降低豆乳酸奶的持水力,离子型多糖对持水力没有显著影响;在质构方面,添加明胶(1%)、卡拉胶(≥0. 05%)可显著提高豆乳酸奶的硬度黏度,低浓度的卡拉胶和高浓度的黄原胶显著降低了豆乳酸奶的弹性,1%明胶也显著提高了豆乳酸奶的内聚性,中性多糖对豆乳酸奶质构特性影响不大;流变学结果表明,1%明胶可以提高豆乳酸奶的黏弹性、屈服应力、稠度系数、假塑性,卡拉胶在高浓度下也可以显著提高豆乳酸奶的黏弹性,所有的亲水胶体都可以显著提高的豆乳酸奶的表观黏度。     

Evaluation of the technological and sensory properties of durum wheat spaghetti enriched with different dietary fibres

The incorporation of fibres, whether insoluble or soluble, in durum wheat pasta negatively impacts desirable end‐use properties, especially if incorporated in significant amounts. Fibres can disrupt the starch–protein matrix of the dough during pasta preparation and can also often swell more readily with water than starch, competing with the starch for water during dough development. Similar degrees of substitution with different fibres gave markedly different impacts on firmness, stickiness, cooking loss and sensory attributes, suggesting that results obtained for one fibre cannot readily be generalized to other fibres. The in vitro starch digestibility of the pastas was significantly reduced when resistant starch, β‐glucan‐enriched flour, carboxymethyl cellulose or guar gum was incorporated but increased when pollard or inulin was added. In many instances, different sources of the same fibre gave dramatically different impacts on the properties of cooked durum wheat pasta. © 2014 Society of Chemical Industry