Effects of Different End‐Point Cooking Temperatures on the Efficiency of Encapsulated Phosphates on Lipid Oxidation Inhibition in Ground Meat

Effects of 0.5% encapsulated (e) phosphates (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation during storage (0, 1, and 7 d) of ground meat (chicken, beef) after being cooked to 3 end‐point cooking temperatures (EPCT; 71, 74, and 77 °C) were evaluated. The use of STP or eSTP resulted in lower (P < 0.05) cooking loss (CL) compared to encapsulated or unencapsulated forms of HMP and SPP. Increasing EPCT led to a significant increase in CL (P < 0.05). Both STP and eSTP increased pH, whereas SPP and eSPP decreased pH (P < 0.05). The higher orthophosphate (OP) was obtained with STP or SPP compared to their encapsulated counterparts (P < 0.05). The lowest OP was determined in samples with HMP or eHMP (P < 0.05). A 77 °C EPCT resulted in lower OP in chicken compared to 74 and 71 °C (P < 0.05), dissimilar to beef, where EPCT did not affect OP. In encapsulated or unencapsulated form, using STP and SPP enhanced reduction in TBARS and lipid hydroperoxides (LPO) compared with HMP (P < 0.05). Regardless of the phosphate type, more effective lipid oxidation inhibition was achieved by the use of encapsulated forms (P < 0.05). Increasing EPCT resulted in lower TBARS in beef and higher LPO values in both beef and chicken samples (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by lowering EPCT.     

冻融循环对熟制鲣鱼暗色肉脂质变化的影响

为探究冻融循环对熟制鲣鱼暗色肉脂质变化的影响,对熟制鲣鱼暗色肉进行冻融循环（0、2、4、6、8 次）贮藏,测定冻融过程中样品的过氧化值（peroxide value,POV）、酸价（acid value,AV）、pH值、脂质组成、脂肪酸组成等指标。结果显示,在冻融循环贮藏过程中,脂质组成发生明显变化,甘油三酯（triacylglycerol,TAG）和磷脂（polar lipid,PL）质量分数明显降低,游离脂肪酸（free fatty acid,FFA）质量分数明显升高。在冻融循环过程中暗色肉的pH值显著减小,POV和AV显著增加（P＜0.05）。脂质中总饱和脂肪酸和总多不饱和脂肪酸含量都逐渐下降,TAG和PL中脂肪酸含量明显下降,其中PL中总多不饱和脂肪酸含量下降明显,FFA中总多不饱和脂肪酸含量显著升高（P＜0.05）。主成分分析（principal component analysis,PCA）和偏最小二乘判别分析（partial least squares discriminant analysis,PLS-DA）结果表明,经过不同冻融次数的鱼肉之间存在一定的差异性,且随着冻融次数的增加脂质氧化程度不断加剧。相关性分析结果表明FFA质量分数与POV、AV呈正相关,与PL质量分数、TAG质量分数、pH值呈负相关。实验结果表明冻融循环会影响熟制鲣鱼暗色肉脂质组成,同时引起脂质的氧化分解。这为熟制鲣鱼暗色肉在运输和贮藏过程中脂质控制提供一定的理论指导。     

Packaging Cooked Turkey Meat Patties while Hot Reduces Lipid Oxidation

Elimination of oxygen by “hot packaging” reduced the 2-thiobarbituric acid reactive substances (TBARS) value of meat patties by about 50% in control and myoglobin added, and between 30-40% in ferrous iron added turkey patties, as compared with “cold packaging.” The TBARS values of hot and cold vacuum packaged patties were significantly lower than those of loosely packaged patties after 1 wk refrigerated storage. Most lipid oxidation in meat patties occurred at day 0, and only small changes in TBARS values were observed after 1 wk storage. Although the prooxidants in meat were major factors in promotion of lipid oxidation of cooked meat, hot packaging minimized their effects.     

迷迭香提取物对牛肉丸冻藏过程中脂肪氧化和品质特性的影噢

将不同浓度的迷迭香提取物（0、0.02%、0.04%和0.06%）添加到牛肉丸中,并以0.02%丁基羟基茴香醚（BHA）做对照,测定迷迭香处理组和对照组牛肉丸在冻藏过程中的过氧化物值（PV）、硫代巴比妥酸值（TBARS）、色差值（L*值、a*值）、保水性和质构特性,并对牛肉丸进行感官评价,考察迷迭香提取物对牛肉丸脂肪氧化和品质特性的改善作用。结果表明,迷迭香提取物可显著降低冻藏牛肉丸的PV值和TBARS值,抑制牛肉丸的脂肪氧化程度;同时,提高牛肉丸的a*值,使其保持良好的色泽;迷迭香提取物还能降低牛肉丸的蒸煮损失和解冻损失,改善牛肉丸的保水性;硬度、弹性和咀嚼性等质构特性也得到改善;感官评价结果显示,迷迭香处理组牛肉丸的感官评分较高,具有良好的感官品质。因此,迷迭香提取物具有抑制冻藏肉牛丸制品脂肪氧化和改善其食用品质的潜在应用价值。     

Inhibition of Lipid Oxidation in Meats by Inorganic Phosphate and Ascorbate Salts

The sodium salts of tripolyphosphate, tetrapyrophosphate, L-ascorbate monophosphate, and L-ascorbate polyphosphate at 0.3% and L-ascorbic acid and sodium L-ascorbate at 0.1% were added to ground turkey and ground beef. Sensory attributes and hexanal content were evaluated immediately after cooking and after 1 and 3 days storage (4°C). Percentages of moisture and fat and nonheme iron were determined. All samples containing a phosphate salt had more meaty flavor and less stale and rancid flavor and aroma and contained less hexanal after 3 days storage than samples with no additive. The addition of phosphate salts decreased cooking losses but did not affect fat content. Phosphate salts decreased nonheme iron in cooked turkey patties but not in beef patties. The taste panel detected a very slight soapy flavor in patties with the addition of any phosphate salt at 0.3%.     

Rosemary Extracts as Inhibitors of Lipid Oxidation and Color Change in Cooked Turkey Products During Refrigerated Storage

ABSTRACT: Water-soluble rosemary extracts were evaluated for their inhibitory effects on lipid oxidation and color change in cooked turkey products during storage. Changes were measured in thiobarbituric acid-reactive substances, hexanal production and color of the cooked turkey samples containing 0, 100, 250 and 500 ppm water-soluble rosemary extracts, at storage day 0, 1, 2, 3, 5, 7, 10, and 13. The rosemary extracts showed significant protection of lipid oxidation and color change in cooked turkey. Higher levels of water-soluble rosemary extracts were more effective in delaying quality loss in cooked turkey at all tested storage times.     

蒸煮鸡肉的挥发性香气成分

采用同时蒸馏萃取法(即SimultaneousDistillationExtractor,以下简称SDE)提取蒸煮鸡肉中的挥发性香气成分,并采用气相色谱质谱联用法(GC-MS)对香气成分进行了鉴定.结果得到化合物44种,共分成9类,其中羰基化合物最多、芳香族次之.羰基化合物对鸡肉特征香气的形成起重要作用,芳香族和呋喃是蒸煮鸡肉的主要香气成分.     

Lipid Oxidation in Cooked Turkey as Affected by Added Antioxidant Enzymes

Catalase (CAT) and glutathione peroxidase (GSH-Px) were added to turkey which had been cooked (80°C) to provide minimal activity of both enzymes, to determine their effects in development of lipid oxidation. CAT (100–500 U/g muscle) decreased the formation of thiobarbituric acid reactive substances (TBARS) 4–28% during 2 days of storage. GSH-Px (4.0 U/g muscle) decreased TBARS 8–11%. CAT (170 U/g muscle) and GSH-Px (1.3 U/g muscle) in combination decreased TBARS formation 7–14%. Reduced glutathione concentrations in the turkey were unaffected by cooking. These data suggest that heat inactivation of CAT and GSH-Px was not the only factor involved in heat-induced lipid oxidation reactions in turkey thigh muscle.     

Effects of Ascorbic Acid and Antioxidants on the Lipid Oxidation and Volatiles of Irradiated Ground Beef

Beef loins, aged for different lengths of time post slaughter, were treated with ionizing radiation. Irradiated ground beef produced volatile sulfur compounds (S‐volatiles) responsible for the unique irradiation odor and accelerated lipid oxidation. The quality changes by irradiation became greater as aging and storage time increased. During aerobic storage, the S‐volatiles disappeared whereas volatile aldehydes drastically increased in irradiated beef. Addition of ascorbic acid at 0.1% (wt/wt) or sesamol +α‐tocopherol at each 0.01% level to ground beef before irradiation effectively reduced lipid oxidation and S‐volatiles. As storage time increased, however, the antioxidant effect of sesamol + tocopherol in irradiated ground beef was superior to that of ascorbic acid.     

Display, Packaging, and Meat Block Location Effects on Color and Lipid Oxidation of Frozen Lean Ground Beef

Ground beef chuck (15% fat) was packaged (500g) in vacuum bags, Saran Wrap^TM overwrapped with aluminum foil or polyvinyl chloride (PVC), exposed to retail display light (4°C) for 24 hr and then held frozen (?18°C) for 52 wk. Instrumental and visual color of PVC-packaged beef was affected most by display and by frozen storage. During frozen storage, as oxygen permeability of packaging material increased, TBA, visual brownness, and metmyoglobin increased while visual redness, acceptability, a* value, red color contributed by oxyrnyoglobin, and deoxymyoglobin decreased. Location on the meat block (exterior vs interior) affected (p<0.05) visual red and brown color, lightness, and acceptability, L*, a*, and b*, and TBA values.     

辐照处理对泠却肉脂肪氧化影响的研究

研究了辐照剂量、贮藏时间和抗氧化剂对冷却肉脂肪氧化的影响。结果表明：辐照处理会加速冷却肉脂肪氧化，辐照剂量越高，脂肪氧化程度越大；在贮藏前期，随着贮藏时间的延长，辐照冷却肉脂肪氧化速度明显加快；在贮藏后期，冷却肉脂肪氧化的程度不能单纯根据过氧化值来判断；抗氧化剂茶多酚可以明显抑制辐照处理和贮藏时间对冷却肉脂肪氧化的影响。     

Effect of α-Tocopherol, β-Carotene, and Sodium Tripolyphosphate on Lipid Oxidation of Refrigerated, Cooked Ground Turkey and Ground Pork

ABSTRACT α-Tocopherol and β-carotene at 0.03% levels and sodium tripolyphosphate (STP) at 0.2% and 0.3% levels, alone and in combination, were added to ground turkey and ground pork. Hexanal was measured after cooking and storage at 4 °C for 2, 4, or 6 d. α-Tocopherol alone significantly reduced hexanal of stored, cooked, turkey but had no effect in pork. STP was more effective than α-tocopherol and a combination of α-tocopherol with STP resulted in enhanced antioxidant activity. Hexanal of pork with 0.03%α-tocopherol plus 0.3% STP did not increase significantly during storage, and that of turkey increased only slightly. β-Carotene and salt (1% NaCl) had no effect on hexanal.     

Effect of Water Activity on Lipid Oxidation and Protein Solubility in Freeze-dried Beef during Storage

ABSTRACT: Ground beef patties (15% fat) were freeze-dried to different a_w endpoints and stored at 25°C or 49°C. Water activity, total moisture (%), lipid oxidation (TBARS@450nm), and protein solubility were evaluated. TBARS @450nm was favored at 49°C, but not at 25°C except at high a_w range (p < 0.05), whereas protein solubility was greater at 25°C than 49°C (p < 0.05). TBARS@450nm values at 49°C were generally greatest at low a_w range (p > 0.05). Protein solubility was lowest at medium a_w at 49°C (p < 0.05), while at 25°C low a_w protected protein solubility better than other low or high a_w values.     

冻藏肉及其制品中蛋白氧化的研究进展

冻藏是肉及其制品最重要的贮藏方式,可有效抑制微生物生长繁殖及酶促反应,从而延长其货架期.然而,肉及其制品在长期冻藏过程中不可避免地发生品质下降.除冰晶、嗜冷微生物、干耗、脂肪氧化等因素外,蛋白氧化在品质劣化中所发挥的作用受到关注.本文综述肉及其制品中蛋白氧化的发生机制、氧化结果以及检测方法;冻藏过程中影响蛋白氧化的因素...     

Rosemary Extract and Precooking Effects on Lipid Oxidation in Heat-Sterilized Meat

The influence of precooking and addition of refined rosemary extract on lipid oxidation during storage of heat-sterilized meat in trays was investigated. Short precooking resulted in increased lipid oxidation, while more extended precooking using peanut oil gave products with higher stability during storage. The addition of a gravy-type sauce (instead of water) to the meat when filling it into trays also resulted in higher storage stability. However, only the application of rosemary extract, especially after precooking, resulted in products with stability similar to those packed with nitrogen flushing.     

热处理对肉品脂质氧化的影响研究进展

加热是常见的肉及肉制品加工方式,适当的加热可改善色泽和风味、杀灭有害的微生物与寄生虫、延长贮藏期、提高消化吸收性,但是,过度加热会导致肉品中的不饱和脂肪酸氧化并促进有害脂质氧化产物的形成,从而降低肉品的营养价值并影响其食品安全.本文综述近年来脂质氧化对肉品风味影响的研究成果,介绍主要的脂质氧化机理,总结加热温度、时间、...     

Conjugated Linoleic Acid Reduces Lipid Oxidation in Aerobically Stored, Cooked Ground Beef Patties

ABSTRACT: The effect of direct addition of conjugated linoleic acid (CLA) on lipid oxidation was studied. CLA and/or fat trim (4% by weight) were added to the lean trim (96%). Thiobarbituric acid reactive substances (TBARS) were determined on days 0, 3, and 7 for cooked or raw patties stored aerobically at 4 °C. Addition of CLA during the grinding process increased CLA isomers in both raw and cooked ground beef and decreased TBARS production ( P < 0.01). CLA caused a greater reduction in TBARS over storage time in cooked patties than in raw patties ( P= 0.006). The concentrations of 18:2n–6 and CLA isomers decreased with storage time. CLA increased 18:2n-6, whereas most fatty acids were decreased by the addition of CLA. CLA did not affect percentages of fat and moisture, cooking loss, or meat color (L*, a *, b *) ( P > 0.60).     

辐照处理肉及其制品的脂肪氧化效应研究

辐照处理肉及肉制品能有效的提高肉品的卫生安全质量、延长保质期。但是，辐照处理会加速肉与肉制品中脂肪的氧化。本文阐述了辐照诱导肉及肉制品脂肪氧化的机理，并对影响脂肪氧化的因素如辐照剂量、环境温度、包装形式以及抗氧化剂筛选及添加量等进行了综述。     

苹果多酚对鲜肉色泽稳定性及脂肪氧化的影响

本文研究了苹果多酚对透氧保鲜膜包装的鲜猪肉的色泽稳定性及脂肪氧化的影响。结果表明,苹果多酚能明显抑制肉中脂肪的氧化,并能提高鲜肉红色的稳定性。单独使用0.05%的苹果多酚,有较好的护色效果。苹果多酚与抗坏血酸或烟酰胺配合使用,抗氧化与护色效果明显增强。0.05%苹果多酚与0.05%烟酰胺配合使用可以使鲜肉在5±1℃条件下贮藏7d后,仍保持稳定的鲜红色,TBA值为0.3mg/kg,TVB-N值为14.7mg/100g。     

不同复热方式对猪耳朵制品挥发性风味和脂肪氧化的影响

利用吹扫捕集-热脱附-气相色谱-质谱联用结合嗅闻技术和硫代巴比妥酸反应活性物质（thiobarbituric acid reaction substances,TBARS）值对不同复热方式（巴氏、水蒸、微波、高温）处理的猪耳朵制品挥发性风味物质含量和脂肪氧化程度进行分析。结果表明,不同复热处理样品共鉴定出58?种风味物质,醛类和烃类物质含量较高;基于风味活性值分析,己醛、辛醛、壬醛、癸醛、（E）-2-癸烯醛、（E,E）-2,4-癸二烯醛、1-辛烯-3-醇、苯酚和丁香酚对复热风味贡献较大;基于主成分分析,水蒸复热样品风味变化不明显;复热猪耳朵制品过熟味（warmed-off flavor,WOF）以亚麻籽油味为主,带有轻微的金属味和酸败味;巴氏复热显著增加WOF关键风味因子含量和TBARS值;微波复热能够较好避免复热WOF的形成。