Sodium Lactate Effect on Sensory Characteristics, Cooked Meat Color and Chemical Composition

Cooked, vacuum packaged beef top rounds injected with 0, 1, 2, 3 or 4% sodium lactate were stored up to 84 days at 0°C. Cooking yields and chemical composition were determined initially, while changes in sensory attributes, Warner-Bratzler shear force and color were evaluated after 0, 14, 28, 42, 56, 70 and 84 days storage. Increasing sodium lactate resulted in higher cooking yields and darker, redder color with less gray surface area. Flavor notes associated with fresh beef were enhanced by addition of sodium lactate, and flavor deterioration during storage was minimized. Palatability was improved by adding 1% sodium lactate, but beyond 1 to 2% it did not further improve. Changes in cooked meat tenderness were verified by Warner-Bratzler shear force measurements.     

不同嫩化方法对鹅肉色泽的影响

本实验比较了几种嫩化处理方法对鹅肉色泽的影响。结果表明,低温处理后,鹅肉的L*、a*、b*值降低,肌红蛋白总量在处理前期也迅速降低,但24～48 h内肌红蛋白总量又增加。低温处理对氧合肌红蛋白的比例影响不大,高铁肌红蛋白和脱氧肌红蛋白的比例成相反变化趋势。木瓜蛋白酶处理的鹅肉其L*值呈现增加趋势,a*、b*值变化较小。木瓜蛋白酶处理对肌红蛋白3 种形式的比例影响较大,添加量为6 U/g、处理时间为70 min时,高铁肌红蛋白的比例最低。磷酸盐处理后鹅肉的L*、b*值降低,a*值变化不明显。但适量的复合磷酸盐处理后,氧合肌红蛋白和脱氧肌红蛋白的比例增加,高铁肌红蛋白的比例极低。综合分析,木瓜蛋白酶处理和复合磷酸盐处理有利于保持鹅肉的色泽,并且在适当应用时可以改善鹅肉的色泽。     

多品种鹅鲜肉成分及品质特性差异分析

选取240 日龄朗德鹅、扬州鹅、浙东白鹅以及皖西白鹅各12 只,取胸肉进行食用品质、营养品质以及挥发性风味物质的测定。结果表明：4 种鹅肉的pH 值均在正常范围值内,肉色较好,皖西白鹅熟肉率最高,食用品质较好,浙东白鹅剪切力最低;4 种鹅肉的蛋白质、脂肪、水分和灰分含量差异均不显著（P＞0.05）;在4 种鹅肉中共检测出30 种脂肪酸,皖西白鹅脂肪酸含量最高,达到51.55 mg/100 g,对鹅肉风味的产生有重要作用,棕榈酸、硬脂酸、山嵛酸、油酸以及二十碳五烯酸是其主要脂肪酸（占比81.83%）,多不饱和脂肪酸占饱和脂肪酸的比值（polyunsaturated fatty acids/saturated fatty acid,PUFA/SFA）为2.52;朗德鹅具有最低的动脉粥样硬化指数（atherogenic index,AI）值（0.23）,其次是皖西白鹅。鹅鲜肉中共检测出17 种氨基酸,其中7 种为必需氨基酸,其中皖西白鹅具有最高的氨基酸含量（41.57 mg/100 g）,鹅肉中必需氨基酸占总氨基酸的比例（essential amino acid/amino acids,EAA/TAA）达到33.12%,鲜味氨基酸含量达到0.96 mg/100 g;共鉴定得到17 种挥发性有机物,醛、酮和酸是鹅生肉的主要风味物质,其中皖西白鹅具有最丰富的挥发性物质类别,3-羟基-2-丁酮、丙酮以及4 种酸是皖西白鹅的风味主体;主成分分析结果表明长链不饱和脂肪酸和部分氨基酸（缬氨酸、亮氨酸、赖氨酸、酪氨酸和精氨酸）分别是皖西白鹅、扬州鹅区别于其他鹅种的主要标志,扬州鹅与浙东白鹅呈现较高的相似度。     

乌珠穆沁羊生长过程中食肉营养成分变化分析

为了解自然放牧乌珠穆沁羊的不同月龄和不同部位骨骼肌的营养成分,选取1、3、6、9、12月龄和18月龄的乌珠穆沁羊,测定其股二头肌、背最长肌、肱三头肌部位的水分、粗蛋白、脂肪和灰分含量.结果表明:随着月龄的增加,水分和灰分含量呈显著性下降趋势(P＜0.05);粗蛋白含量在3月龄时较低,其他月龄间无明显差异;脂肪含量9月龄和18月龄时较高,3月龄和12月龄时较低.可以看出脂肪含量随着月龄及季节环境的改变其含量也随着变化,其他水分、粗蛋白、灰分含量不易跟季节环境因素而变化.不同部位间水分、蛋白、脂肪、灰分含量的显著性差异各月龄间无规律性,但从大体上部位因素对灰分和脂肪的影响较小.     

杀菌方式对红烧老鹅脂肪酸组成和挥发性风味的影响

比较研究电子束（0、3、6、9、12?kGy）、60Co-γ射线（0、3、6、9、12?kGy）、105、121?℃杀菌处理对真空包装红烧老鹅脂肪氧化硫代巴比妥酸反应物（thiobarbituric acid reactive substances,TBARS）值、脂肪酸含量及挥发性风味的影响。结果表明：高剂量的电子束、60Co-γ射线及高温处理可加速红烧老鹅肉脂质的氧化,9?kGy剂量的60Co-γ射线对红烧老鹅TBARS值的影响最为显著（P＜0.05）;饱和脂肪酸和单不饱和脂肪酸的含量随电子束、60Co-γ射线辐照剂量的增加而显著增加（P＜0.05）,105?℃杀菌组饱和脂肪酸含量显著高于121?℃杀菌组（P＜0.05）,而105?℃杀菌组单不饱和脂肪含量显著低于121?℃杀菌组（P＜0.05）;多不饱和脂肪酸的含量则随电子束、60Co-γ射线辐照剂量的增加而显著减少（P＜0.05）,105?℃杀菌组多不饱和脂肪酸含量显著高于121?℃杀菌组（P＜0.05）;电子鼻检测挥发性风味变化,表明3?kGy的电子束和60Co-γ射线、105?℃及空白组的风味差异较小。因此,低剂量电子束或60Co-γ射线辐照（＜6?kGy）和105?℃处理对红烧老鹅肉脂肪酸组成和挥发性风味的影响较小,可为红烧老鹅产品选择不同的杀菌方式提供可行性依据。     

不同犊牛肉加工产品中挥发性风味成分分析

采用气相色谱-质谱联用（gas chromatography-mass spectrometry,GC-MS）结合电子鼻和电子舌技术对犊牛肉、犊牛排、犊牛肉干以及调理犊牛肉饼进行挥发性风味成分的测定,为不同犊牛肉产品的挥发性风味鉴定提供相应数据参考。结果表明：电子鼻/电子舌技术结合主成分分析（principal component analysis,PCA）与雷达图分析可对犊牛肉及其3组产品的主要挥发性风味贡献物质进行直观区分;利用GC-MS技术从犊牛肉及3组产品中共鉴定出36种挥发性风味物质,其中犊牛肉组、犊牛排组、犊牛肉干组和调理犊牛肉饼组分别检测出14、19、26和23种挥发性成分,其中乙酸、己醛、庚醛、壬醛、1-辛烯-3-醇、正己醇、3-羟基-2-丁酮和茴香脑为犊牛肉系列产品中的主要风味成分,戊醛、2,3-丁二醇和萘构成3组犊牛肉加工产品的主要风味成分。     

Texture of Emulsified Cooked Meat Products by Three Different Methods of Measurement

A comparison was made of Warner-Bratzler (W-B) shear with penetration and compression tests of the texture of frankfurters undergoing textural deterioration during storage in vinegar pickle. The various measurements were linearly covariant but the intercepts were finite, indicating the different tests were not measuring the same properties in the same proportions. Covariant plots of W-B shear of whole frankfurters and penetration of the interior gel showed that the skin did not deteriorate to the extent of the interior emulsion did. Covariant plots of work and maximum force values for all three techniques showed that the maximum stress forces decreased more rapidly than did the average work function during storage in pickle.     

不同品种兔肉营养成分与质构比较研究

为丰富我国兔肉营养数据库,测定并分析四川、山东两地伊拉兔、伊高乐兔和伊普吕兔肉的水分、粗蛋白、粗脂肪、灰分、矿物质、氨基酸和脂肪酸等营养成分组成及含量以及硬度、弹性、胶着性等质构指标差异。结果表明:不同地区和品种兔肉的水分、蛋白质和脂肪含量存在显著差异(P<0.05),其中山东地区伊高乐兔肉水分含量最低、蛋白质含量最高,四川地区伊拉兔肉脂肪含量最低;不同地区和品种兔肉灰分、矿物质含量以及脂肪酸、氨基酸组成与含量无明显差异;山东地区伊高乐兔肉硬度低、弹性好、咀嚼性高,口感最好,四川地区伊普吕兔肉硬度高、胶着性高,口感最差。兔肉的营养成分与质构特性存在品种和地区差异,山东地区伊高乐兔肉营养成分和质构特性优于其他5种兔肉。     

不同烹饪方式对海参体壁营养成分变化的对比分析

为了探究不同烹饪方式对海参体壁营养成分的影响,将鲜活海参分别使用常压烹饪、高压烹饪、重汤烹饪方式进行烹饪。对比不同烹饪方式下海参外观、体壁组织变化、海参失水率、失重率、收缩率、海参体壁营养成分及海参体壁质构变化。研究结果显示,高压烹饪组海参体壁水分、水溶性蛋白、胶原蛋白、多糖含量分别为84.27%、0.58%、1.73%、0.76%、2.73%,常压烹饪组海参体壁水分、水溶性蛋白、胶原蛋白、多糖含量分别87.58%、0.36%、1.92%、1.92%,重汤烹饪组海参体壁水分、水溶性蛋白、胶原蛋白、多糖含量分别为86.62%、0.46%、1.82%、0.81%。重汤烹饪组在海参体壁水分、水溶性蛋白、胶原蛋白、多糖含量上介于高压烹饪组、常压烹饪组之间,具有统计学差异(p<0.05)。结果表明重汤烹饪下的海参体壁组织较为完整,体壁营养成分保留较多,且对海参体壁的质构影响较小,符合海参烹饪的要求。     

不同烹饪方式处理的鲟鱼肉营养成分和风味比较

为了探究烹饪方式对鲟鱼肉的蛋白质营养价值和风味物质含量的影响,该研究以人工养殖的鲟鱼肉为原料,比较了清蒸和煎炸烹饪方式,对鲟鱼肉的基本营养物质、氨基酸、蛋白质、风味化合物含量,以及氨基酸指数(AAS、EAAI)、蛋白质效价的影响,结果表明,以生鱼肉为对照,清蒸和煎炸使鲟鱼肉的水分含量分别降低了56.41％和43.73％...     

不同黔北麻羊加工产品中挥发性风味物质分析

为研究不同黔北麻羊加工产品风味物质的变化规律,采用顶空固相微萃取和气相色谱-质谱联用技术对挥发性风味成分进行鉴定和分析。结果表明：生羊肉、白切羊肉、清汤羊肉及红汤羊肉中共检测出76 种挥发性风味成分,以醛类、烃类、酮类为主;主成分分析表明,柠檬烯、茴香烯、石竹烯、芳樟醇、2,3-辛二酮、草蒿脑、己醛、壬醛和辛醇为黔北麻羊系列产品的主要风味成分;韦恩图分析表明,己醛、壬醛和辛醇构成黔北麻羊4 种系列产品风味的基本骨架,己醛、壬醛、辛醇、柠檬烯和石竹烯构成黔北麻羊3 种加工产品的主要风味骨架。     

Does It Look Cooked? A Review of Factors That Influence Cooked Meat Color

ABSTRACT:  Adequate cooking of meat is necessary to inactivate microbial pathogens. This is particularly important for ground meat products and some variety meats where pathogens can be present internally. Consumers are being advised on appropriate temperatures to which meat products should be cooked, and to use a meat thermometer to ensure these temperatures are reached. However, consumers are more likely to assess cooking status by the color of the meat or juice. This article reviews the factors that can influence the final color of cooked meat. In most instances, these factors influence color by modifying the meat pigment myoglobin prior to and during cooking. Many factors can prolong the pink "uncooked" color in meat, including high pH, modified atmosphere packaging, rapid thawing, low fat content, nitrite, and irradiation. Such factors may lead to overcooking and loss of food quality, and consumer rejection. Alternatively, factors that cause "premature browning" of meat, where the interior of the product looks cooked but a microbiologically safe temperature has not been reached, are food safety issues. Pale, soft exudative meats can prematurely brown, as can meats packaged under oxygenated conditions, frozen in bulk or thawed over long periods, or those that have had salts or lean finely textured beef added. Meats cooked from a frozen state or irradiated in aerobic conditions might also be at risk, but this might depend on meat species. In summary, the color of cooked meat is not a good indicator of adequate cooking, and the use of a food thermometer is recommended.     

Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel

Amino acid, vitamin (A, E, B₁, B₂, B₃ and B₆), and proximate composition were determined in raw and cooked horse mackerel. The changes in amino acid, vitamin, and proximate content were found to be significant for all cooking methods (frying, grilling, and steaming). Cooking did in general significantly increase the contents of essential, semi-essential, and other amino acids compared to raw fish species. Amino acid contents of grilled mackerel were significantly higher (p < 0.05) than those found in fried and steamed mackerel. The A, E, B₂, and B₆ vitamin content of fried horse mackerel was found to be significantly (p < 0.05) higher than the grilled and steamed samples. The B₁ content of steamed and B₃ content of grilled were found higher than the other cooked samples. Moisture, protein, fat, ash, and carbohydrate contents of cooked fish ranged between 56.52% to 61.34%, 20.79% and 23.93%, 13.44% and 19.61%, 1.70% and 2.47%, and 1.02% and 4.36 %, respectively. Fried fish had intermediate fat values, while grilled and steamed fishes had a comparatively low value.     

不同日龄鹅肉卤制后的理化性质

卤鹅因其独特的风味特点和口感而备受消费者欢迎,为了解其品质随日龄的变化,测定70、80、90 日 龄卤鹅胸肌和腿肌肉的理化指标。结果表明：日龄对卤鹅肉的粗蛋白质、粗灰分和非必需氨基酸含量有显著影响 （P＜0.05）;部位对卤鹅肉的pH值、亮度值、红度值、粗脂肪、饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸 和非必需氨基酸含量有显著影响（P＜0.05）;各理化指标在不同日龄和部位之间的变化具有一定波动性,无一致 的规律性;不同日龄鹅肉卤制后的理化性质在聚类关系上趋同性强,而不同部位鹅肉卤制后理化性质的聚类关系较 远。综上所述,日龄和部位对卤鹅肉物理性状的影响较小,对营养成分的影响较大,并且部位是影响卤鹅肉品质的 主要因素。综合来看,80 日龄卤鹅肉的营养价值较高,且腿肌肉比胸肌更有营养。     

日龄对鹅肉营养和风味品质的影响

对比分析不同日龄的嫩鹅(70日)和老鹅(300日)鹅肉营养组成和风味品质间的差异,对鹅肉的基本成分组成、脂肪酸组成、游离氨基酸组成、挥发性香气成分和质构特性进行检测。结果表明:嫩鹅肌肉中水分和脂肪含量显著高于老鹅(P0.05);在嫩鹅与老鹅肉样中确定出14种脂肪酸成分且在种类上无差异,两者饱和脂肪酸相对含量相近,嫩鹅中单不饱和脂肪酸含量低于老鹅,但多不饱和脂肪酸和必需脂肪酸相对含量较高,2种鹅肉中多不饱和脂肪酸与饱和脂肪酸比值均高于一般膳食要求,且嫩鹅要高于老鹅;嫩鹅和老鹅鹅肉中均检出15种游离氨基酸,老鹅鹅肉中的必需氨基酸含量要高于嫩鹅。在氨基酸风味对比上嫩鹅相比于老鹅具有更高比例的甜味氨基酸和更低比例的苦味氨基酸;嫩鹅与老鹅鹅肉中挥发性成分种类差别较小,但各种风味物质相对含量相差很大,其中老鹅鹅肉中醇类、萜烯类化合物相对含量相对于嫩鹅有所下降,酯类化合物相对含量有所上升;在质构特性上,嫩鹅与老鹅鹅肉间的硬度、弹性、内聚性和咀嚼性均存在显著性差异(P0.05),且老鹅鹅肉的硬度、内聚性、咀嚼性高于嫩鹅,弹性要低于嫩鹅,而嫩鹅与老鹅间黏附性无显著性差异(P0.05)。     

不同部位牦牛肉氨基酸、脂肪酸含量分析与营养价值评价

为明确不同部位牦牛肉氨基酸、脂肪酸等营养物质含量,采集西藏那曲牦牛的上脑、里脊、外脊、米龙、臀肉、腱子肉、腹肉、肩肉及胸肉9 个部位分割肉,测定其蛋白质、脂肪、灰分、氨基酸和脂肪酸组成。结果表明：不同部位牦牛肉的蛋白质含量为19.30%～24.20%,其中腹肉中蛋白质含量最低,外脊中最高;脂肪含量为1.03%～22.47%,腹肉中脂肪含量显著高于其他各部位,米龙、外脊、臀肉和肩肉中脂肪含量较低,不足1.5%。在测定的18 种氨基酸中,谷氨酸含量最高,其次是赖氨酸、天冬氨酸、亮氨酸和精氨酸;腹肉中氨基酸含量显著低于其他部位（P＜0.05）,9 个不同部位牦牛肉中必需氨基酸占总氨基酸的比例为39.03%～40.00%,与联合国粮农组织/世界卫生组织的推荐值接近;里脊和外脊能够满足所有膳食氨基酸需要,上脑、米龙、臀肉、腱子肉、腹肉、肩肉及胸肉中,缬氨酸是限制性氨基酸。脂肪酸总量由大到小为腹肉＞上脑＞里脊＞臀肉＞外脊＞胸肉＞肩肉＞腱子肉＞米龙,油酸、棕榈酸和硬脂酸是牦牛肉中主要的脂肪酸,二十二碳六烯酸、二十碳五烯酸等n-3脂肪酸含量较少,n-6/n-3比值高于膳食推荐值。以常规营养组分、氨基酸组成和脂肪酸组成分别进行聚类分析,总体可分为腹肉、上脑与其他部位肉三大类。综上所述,不同部位牦牛肉中蛋白质、脂肪、氨基酸及脂肪酸等营养物质含量存在差异。     

Cholesterol Content of Raw and Cooked Beef Longissimus Muscles with Different Degrees of Marbling

The relationships of marbling level (eight levels from “Moderately Abundant” to “Practically Devoid”) and cooking to cholesterol content of beef longissimus muscle steaks were studied. Only raw steaks with “Practically Devoid” marbling contained significantly less cholesterol (wet basis) than did raw steaks with any of the other seven marbling scores. However, steaks cooked to an internal temperature of 60° or 75°C showed no significant differences in cholesterol content among any of the eight marbling groups. The cholesterol content of cooked steaks was 22–48% higher than that of raw steaks when cooked to 60°C and 38–65% higher when cooked to 75°C; cooking reduced the weight of each steak, thereby increasing the cholesterol content of the steak expressed as a percentage of the cooked weight.