脂肪含量对肉糜性质影响

在低脂肉制品制作中脂肪被水所取代 ,通过对不同脂肪含量 (30 %、2 0 %、1 0 % )肉糜乳化稳定性、色泽、质构等性质的测量 ,发现随着脂肪含量的降低 ,产品硬度值下降。各样品产量、成品稳定性与乳化稳定性具有相关性。试验结果表明 ,高温产品各种性质较低温产品差     

剪切条件下制备的肉糜中脂肪微粒的微观结构特点

研究在剪切条件下制备的肉糜中脂肪微粒分布规律及微观结构特点。以猪背最长肌为原料,绞碎斩拌3min后再加入背膘斩拌5min。分别用光学显微镜和电子显微镜对肉糜和凝胶进行电镜观察。结果表明：在剪切过程中,背膘被剪切成大小形状各不相同的液态脂肪滴和固态脂肪颗粒,有的脂肪滴和脂肪颗粒能够聚集形成脂肪微粒簇。其表面都包被着一层蛋白膜,或单独地或相互交联分散在蛋白基质中。     

芦丁对冷藏猪肉糜脂肪和蛋白氧化及品质特性的影响

研究不同浓度(0、0.05、0.1和0.2 g/kg)的多酚物质芦丁对冷藏猪肉糜的抗氧化效果及其对肉糜品质特性的影响,并以0.2 g/kg叔丁基羟基茴香醚(butylhydroxyanisole,BHA)作为对照,测定了硫代巴比妥酸值(TBARS值)、总巯基含量、羰基含量、表面疏水性以及猪肉糜的色泽、蒸煮损失和质构特性。结果表明:芦丁对TBARS生成、总巯基损失、表面疏水性的增加具有一定的抑制作用,但对羰基含量不具有抑制作用,且高浓度芦丁反而促进了羰基氧化产物的生成;芦丁能提高肉糜红度值,减少蒸煮损失,并能提高熟肉糜的硬度和弹性等质构特性。因此,适量的芦丁对抑制猪肉脂肪和蛋白氧化以及改善其品质特性具有较好的作用。     

没食子酸对猪肉糜脂肪和蛋白氧化的抑制作用及对肉糜品质特性的影响

为研究没食子酸对冷藏（4 ℃,9 d）猪肉糜脂肪和蛋白氧化的抑制作用及对肉糜品质的影响,将没食子酸添加到猪肉糜中（0、0.05、0.10、0.20 g/kg）,添加0.20 g/kg叔丁基羟基茴香醚（butylated hydroxyanisole,BHA）作为对照组,对肉糜的硫代巴比妥酸（thiobarbituric acid reactive substances,TBARs）值、总巯基含量、羰基含量、表面疏水性、色泽及蒸煮损失进行分析。结果表明：空白组猪肉糜的TBARs值显著增加,蛋白质总巯基含量降低,羰基含量增加,表面疏水性升高,红度值降低,蒸煮损失增加;没食子酸的添加降低了TBARs值的增加幅度,抑制了羰基化合物的生成和表面疏水性的增加,并且随着贮藏时间的增加,能够减少总疏基含量的损失,降低脂肪氧化和蛋白氧化的程度,没食子酸还有利于猪肉糜红度的保持,但对蒸煮损失无改善作用。因此,没食子酸可作为天然抗氧化剂应用于肉及肉制品中。     

剪切时间对肉糜中微粒分散特性的影响

为形成乳化性良好的肉糜,研究不同剪切时间对肉糜中脂肪微粒粒径的影响。实验以猪背最长肌和背膘为原料肉,在3000r/min剪切速率下分别斩拌1、3、5、7min制成生肉糜,利用激光粒度分析仪测定不同剪切时间下肉糜中脂肪微粒大小和粒度分布特点。结果显示：剪切5min和7min条件下,肉糜中脂肪微粒粒径比较小、粒度分布集中,且无显著性差异。     

脂肪、盐和大豆分离蛋白对肉糜的影响

以脂肪、盐和大豆分离蛋白为原料制备肉糜，并对肉糜的得率和质构特性进行考察，以此为指标，通过响应面分析确定肉糜品质较好的工艺条件。研究表明肉糜品质较好的实验条件为：脂肪含量25％、盐含量2％和大豆分离蛋白含量2％附近。     

亲水胶体取代肉糜脂肪的研究

本实验按现在通行的肉糜加工方法加工样品,并在样品中添加不同水平的大豆分离蛋白、魔芋精粉、黄原胶、卡拉胶取代部分脂肪,研究了各水平含量对肉糜凝胶强度、持水性、加热稳定性、乳化稳定性的影响.通过正交试验筛选出最佳配方水平为大豆分离蛋白 2.0%,魔芋精粉2.0%,黄原胶0.4%和卡拉胶0.3%.对最佳配方亲水胶体作成的肉糜制品在不同温度、不同加热时间下进行感官评定,确定在含水量35%,100℃加热1.5h条件下肉糜品质最好.     

淀粉种类对兔肉肉糜凝胶品质的影响

以兔肉为原料制备兔肉肉糜凝胶,测定兔肉肉糜凝胶的持水性、凝胶强度、冻融损失、乳化稳定性等,研究不同种类的淀粉对兔肉肉糜凝胶品质特性的影响。结果表明:添加的4种淀粉均可以显著改善产品的持水性、凝胶强度、冻融损失,使产品有良好的乳化稳定性,显微结构图显示添加淀粉后凝胶的结构得到明显改善,网状结构更加致密有序。同时,淀粉的添加还能改善产品的感官品质。变性淀粉对肉糜凝胶品质的影响要优于天然淀粉。4种淀粉中玉米变性淀粉的效果最好。     

乳酸菌发酵对鳙鱼肉糜菌相与品质的影响

以不同乳酸菌菌株发酵鳙鱼肉糜,对其发酵过程中菌相和品质变化进行分析。结果表明：乳酸菌发酵可显著降低鳙鱼肉糜的pH值,抑制腐败菌的生长,降低挥发性盐基氮的生成量,同时还可增强鳙鱼肉糜的凝胶强度和白度。SDS-PAGE分析表明,乳酸菌发酵可促进鳙鱼肉糜蛋白质的降解。     

脂肪蛋白比对肉糜特性的影响

为研究脂肪蛋白比对肉糜特性的影响,分别测定肉糜的乳化稳定性、颜色、pH 值、质构特性、流变特性和微观结构等指标。结果表明：脂肪蛋白比较大(29:13)的肉糜加热后游离出的液体质量百分比和脂肪质量百分比均显著大于脂肪蛋白比小(9:12)和中间水平(18:12)处理组(P ＜ 0.05);随着脂肪蛋白比增大,肉糜凝胶亮度值(L*)值显著增加(P ＜ 0.05),而红度值(a*)和黄度值(b*)均显著降低(P ＜ 0.05);脂肪蛋白比大的肉糜的凝胶硬度显著大于脂肪蛋白比小和中间水平处理组(P ＜ 0.05),但弹性值却显著小于后两种处理组(P ＜ 0.05);脂肪蛋白比中间水平的凝胶胶黏性和咀嚼性最大,脂肪蛋白比小的次之,脂肪蛋白比大的最差;脂肪蛋白比小,肉糜体系储能模量(G')值小,脂肪蛋白比大,G' 值大;脂肪蛋白比小和中间水平的凝胶结构致密、完整,网孔小而均匀,而脂肪蛋白比大的凝胶结构疏松、不完整,出现不少残留蛋白膜。因而,中等脂肪蛋白比(18:12)能够形成乳化性能好的肉糜。     

糊的组成成分对挂糊油炸肉制品品质影响的研究进展

挂糊油炸肉制品作为一类重要的传统食品,具有色泽金黄、外壳酥脆等特点,深受消费者的喜爱。随着人们消费水平的提高和健康意识的增强,具有低吸油率和高食用品质(外脆里嫩)的油炸制品引起了科研人员的广泛关注。糊的组成、油炸工艺条件、油炸用油等均会影响挂糊油炸肉制品的品质。其中,糊的组成成分是重要的影响因素。通过查阅国内外大量文献,详述了淀粉、蛋白质、食用胶等糊的组成成分对挂糊油炸肉制品品质影响的研究进展,可为油炸食品的原料选择提供一定的科学依据,从而利于挂糊油炸肉制品的工业化生产。      

脂肪剪切乳化和蛋白基质对肉糜乳化稳定性的重要作用

完全粉碎肉制品由肌肉蛋白质、脂肪颗粒、水、盐和碳水化合物等物质组成。在肉糜生产过程中,脂肪被剪切成形状和大小不同的固态脂肪颗粒或液态脂肪滴,如何防止脂肪和水分从产品中分离成为挑战。在过去几十年里,涌现出两种学说用于解释肉糊乳化稳定性：水包油型乳化学说和蛋白基质物理镶嵌固定学说,前者强调脂肪球周围形成界面蛋白膜作用,后者强调蛋白基质对脂肪的固定作用。本文讨论了支持这两个研究方向的成果,并在此基础上提出几点建议。     

The influence of batter formulation and predrying time on interparticle space fractions of a coated meat analog

The purpose of the study was to understand the mechanism of microstructural changes in vegetable‐based meat analogs coated with different batter formulations. A meat analog (substrate) was developed by using vegetable proteins, coated with batters formulated from different combinations of wheat and rice flours, predried at various durations, and subsequently fried. The effect of batter formulation, predrying time, and frying time on spaces occupied by air (porosity, SOA), moisture (SOM), and fat (SOF) in the core region (the meat analog) was studied. The SOA, SOM, and SOF ranged between 8.28–32.72%, 16.73–58.31%, and 16.73–58.31%, respectively. All three fractions of pores in the meat analog were significantly influenced by predrying and frying times; however, batter formulation did not show any significant influence. Batter formulation did not show any significant influence on moisture and fat content within the meat analog. Fat content was not influenced by frying time; and only 90 min predrying made a difference.     

宰后成熟时间与温度对牦牛肉品质影响

牦牛肉热剔骨真空包装后分别于2、10℃成熟,在成熟1、2、3、4、6、12、18d分别测定pH、剪切力、蒸煮损失及肉色值,研究时间及温度对牦牛肉成熟过程中品质变化的影响。结果表明:1~12d贮藏过程中,2℃成熟的牦牛肉pH持续上升,10℃成熟的牦牛肉pH变化不明显,12~18d中两者pH均有不同程度降低;2、10℃成熟对牦牛肉嫩度均有明显改善作用,但是10℃成熟牦牛肉剪切力极显著低于2℃成熟;牦牛肉成熟过程中肉色L*、a*、b*、C*、h呈现整体上升趋势。总体认为热剔骨牦牛肉真空包装于2℃成熟18d可以基本完成成熟;而达到相同成熟品质,10℃成熟较2℃成熟需要时间更短。      

Effect of batter freezing conditions and resting time on cake quality

The aim of the present study was to investigate the effects of batter freezing and conditions and resting time before baking on quality of two kinds of cakes (layer and sponge cakes), including freezing temperature (−18 °C, −26 °C), storage time at sub-zero temperatures (30 and 100 days), and resting time (60 and 120 min). Characteristics of the batter (pH, density, viscosity, and microstructure) and cakes (density, texture, and colour) were analysed. Freezing process increases batter density and viscosity, and consequently decreases cake volume and height, but increases hardness. Cakes from frozen batters have a darker and more yellow crumb and lighter-coloured crust than cakes from non-frozen batters. Freezing process has a greater effect on batter and cake quality characteristics than storage/freezing conditions or resting time. In layer cakes, freezing mainly affected volume and colour, whilst in sponge cakes, there was a more marked effect on texture. Differences between the two kinds of cake could be related to a distinct internal structure. Resting time mainly affected batter characteristics, although there were no apparent differences in the quality of the cakes obtained.     

Effect of maltodextrin and emulsifiers on the viscosity of cake batter and on the quality of cakes

The effect of fat replacement by maltodextrin on cake batter viscosity and the quality of the resultant cakes was studied. The viscosity of batter was reduced significantly when fat was replaced with equal quantities of maltodextrin. Cakes prepared from this batter had low volume and firmer texture. Relatively better cakes were obtained when lower quantities of maltodextrin were used in the formulation. Viscosity of the above cake batter was relatively higher. A relationship between batter viscosity and cake volume was observed. Further improvement in cake volume could be achieved using emulsifiers. In the presence of glycerol monostearate little improvement in cake batter was observed, but the resultant cake volume was improved. However, sodium steroyl lactylate, which improved the batter viscosity, did not improve the cake volume or texture. Copyright © 2005 Society of Chemical Industry     

不同季节和运输时间对肉鸡应激及肌肉品质的影响

126只白羽肉鸡随机分配到6个处理组,处理因素分别为季节(夏季、冬季)、运输时间(0.5、3、5h),工厂条件宰杀取样,分别测定血液和肌肉指标,研究不同季节和运输时间对肉鸡应激及肌肉品质的影响。数据表明,夏季运输时,随着运输时间的延长,ACTH、CORT、CK、LDH水平呈上升趋势,运输5h肉鸡应激水平达到最大值,此时的GLU含量最低;0.5h运输肉鸡L*值最大,pH最低,保水性最差。冬季运输时,肉鸡3h运输后,ACTH、CORT、CK、LDH水平达到最高,继续运输则其水平下降,其余指标的变化趋势则和夏季运输类似。和冬季运输相比,夏季运输肉鸡血液中的应激指标含量更高,宰后肌肉亮度L*值、滴水损失和蒸煮损失更高,pH较低。结果表明,季节和运输时间可以影响肉鸡的应激水平和肌肉品质,不同的季节应该选择合适的运输时间,从而降低运输应激,提高宰后肌肉品质。      

Texture,colour and sensory evaluation of a conventionally and ohmically cooked meat emulsion batter

Samples of meat emulsion batter were steam or ohmically cooked (at voltage densities ranging from 3 to 7 V cm^?1) to standardized cook values (C_s) or to target end point temperatures (EPT). Higher ohmic voltage densities produced faster heating rates. Texture profile analysis (TPA) of ohmic and steam‐cooked frankfurters showed no significant difference (p ≥ 0.05) in any of the attributes assessed with the exception of springiness, which was significantly lower (p < 0.05) in ohmically cooked samples heated to similar C_s values, although this trend was less pronounced in samples cooked to similar EPT. Instrumental colour evaluations revealed that ohmically cooked samples (cooked both to similar C_s and EPT) differed from steam‐cooked in both a* and hue angle values (especially at 5–7 V cm^?1 (p < 0.05)). Although instrumental measurements revealed differences in selected texture and colour attributes, panellists were not able to distinguish between steam and similar EPT ohmically cooked samples (p < 0.05). Thus while subtle differences may exist in the eating quality of ohmic and steam‐cooked emulsions, these differences are unlikely to be of an order of magnitude to affect consumer acceptance of ohmically cooked meat emulsion products. Copyright © 2004 Society of Chemical Industry     

Effects of pre‐emulsifying fat/oil on meat batter stability,texture and microstructure

The effects of pre‐emulsified beef fat and canola oil (CO) (25%) with Tween 80 (T‐80) or sodium caseinate (SC) were studied in beef meat batters prepared at three protein levels (9%, 12% and 15%). Raising meat protein level to 15% resulted in low emulsion stability of products prepared with CO. Using pre‐emulsified beef fat with Tween 80 (BF‐T80) showed significantly higher fat and water losses at all protein levels. There were no differences in fat and water losses between pre‐emulsified beef fat and CO when SC was used at the 9% and 12% protein levels compared to the controls (non pre‐emulsification). Light microscopy revealed fat globule coalescence in the CO meat batters prepared with 15% protein and BF‐T8 treatments, as well as formation of fat channels and more protein aggregation; both resulted in lower emulsion stability. Using SC to emulsify fat/oil produced a finer dispersion of fat globules compared to all the other treatments.     

脂肪替代品在低脂肉制品中的研究进展

由于低脂肉制品可有效降低脂肪的摄入,且能预防高脂膳食所引起的各种慢性疾病,相关研究领域逐渐成为近年来的研究热点。本文基于国内外低脂肉制品的发展现状,从脂肪替代物、脂肪模拟物和复合型脂肪替代物三个方面综述了各自对低脂肉制品组成成分、组织结构、抗氧化性及感官评价等指标影响的最新研究进展,并就肉制品中脂肪替代物的发展方向进行了展望。