焦糖色配方的工艺优化

为烹饪中的焦糖色标准化和科学化生产提供科学依据,对焦糖色的最优配方和制作工艺进行了研究。以感官评分为标准,通过单因素试验和响应面试验研究了白砂糖添加量、加热时间、沸水添加量的影响。确定焦糖色最佳制作配方和工艺条件为:白砂糖添加量为153.51 g,加热时间为8.91 min,沸水添加量为99.88 g。经此配方工艺制作的焦糖色感官评分高达98.7,具有焦香味浓郁,色泽呈深黑红棕色且富有光泽等特点。最后,以卤肉为载体,比较焦糖色与常用食品增色剂老抽酱油以及焦糖色和老抽酱油混合物(老抽:焦糖=1:1混合,m/m)对食品色泽参数包括亮度L*值、红度a*值、黄度b*值、彩度c*值的影响。结果表明,三种食品增色剂对卤肉的亮度L*值和黄度b*值和彩度c*值没有显著性差异(p>0.05),对卤肉的红度a*值差异显著(p<0.05),说明焦糖色能够提高卤肉的光泽度和红度,与感官评定结果一致。     

A U.S. population dietary exposure assessment for 4-methylimidazole (4-MEI) from foods containing caramel colour and from formation of 4-MEI through the thermal treatment of food

ABSTRACT

4-Methylimidazole (4-MEI) is formed in caramel colours produced using ammonium compounds (Class III and Class IV caramel colours). 4-MEI can also form in food through Maillard reactions between reducing sugars and amino acids during cooking, roasting or dry-heating. The USFDA has analysed over 700 food and beverage samples collected from 2013 to 2015 for the presence of 4-MEI. These samples include foods containing added caramel colour and foods that are not labelled as containing added caramel colour, but which may contain 4-MEI resulting from thermal treatment. The 4-MEI levels in all food samples were quantified using LC-MS/MS. These data were used to develop a comprehensive dietary exposure assessment for 4-MEI for the U.S. population aged 2 years or more and several sub-populations, using two non-consecutive days of food consumption data from the combined 2009–2012 National Health and Nutrition Examination Survey and 10–14-day food consumption survey data for 2009–2012 from the NPD Group, Inc. National Eating Trends–Nutrient Intake Database. Dietary exposure estimates were prepared for each category of foods labelled as containing added caramel colour and of foods not labelled as containing added caramel colour, but which may contain 4-MEI from thermal treatment. Exposure to 4-MEI from consumption of foods containing added caramel colour was higher than that from foods that contain 4-MEI from thermal treatment for all population groups. Cola-type carbonated beverages were the highest contributors for most populations from foods containing added caramel colour. Coffee was the highest contributor for most populations from foods in which 4-MEI could be formed from thermal treatment. An overall combined exposure to 4-MEI was also estimated that included all foods identified as containing added caramel colour and foods in which 4-MEI could be formed by thermal treatment.     

济宁市市售肉制品亚硝酸盐含量的测定

目的深入调查肉制品食用添加剂,特别是市售肉制品添加亚硝酸盐的状况。方法采用随机抽样方法,检测了济宁市肉制品市场熟肉制品的亚硝酸盐含量。结果共检测各类熟肉制品596份,超标208份,超标率为34.8 9%。结论亚硝酸盐在熟肉制品中的添加量不当,过多食用亚硝酸盐超标的熟肉制品对人体造成了一定的危害,应加强对熟肉制品的市场监督。     

Rapid determination of 4‐methylimidazole in caramel colours using 1H NMR spectroscopy

A method utilizing ¹H NMR spectroscopy has been developed to measure the concentration of 4‐methylimidazole in caramel colours used as food additive (E150a‐d). For sample preparation, a very simple dilution with water‐ethanol mixture and addition of internal standard is sufficient. 4‐Methylimidazole produces a distinct peak of the methyl group of the molecule in the δ 2.27–2.25 ppm range, where it can be distinguished from other matrix compounds. The method was shown to be of adequate sensitivity with a limit of detection (LOD) of 5.0 mg/L adequate to control the 4‐methylimidazole regulatory limit. The developed method was applied for the analysis of 7 authentic food colourings. Only two products (E150d) contained detectable concentrations of 4‐methylimidazole (662 mg/kg and 401 mg/kg). The NMR method may be used by governmental or industry laboratories for routine control of food colourings.     

Inactivation of Nisin by Glutathione in Fresh Meat

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to determine the fate of nisin in meat products. Nisin in 0.02N HCl was added to fresh and cooked meat and meat juice and samples were stored at 4 °C overnight. Residual nisin solutions and meat juice and meat extract supernatants were analyzed for antimicrobial activity and for nisin. Nisin was recovered from cooked meat extract and cooked meat juice; however, only nisin bound to a food component was detected in fresh meat extract. Mass spectra for raw meat and juice showed a signal 307 Da greater than the mass of nisin. Results indicated that nisin was likely inactivated in raw meat by an enzymatic reaction with glutathione.     

Simple and Fast Sample Preparation Followed by Gas Chromatography‐Tandem Mass Spectrometry (GC‐MS/MS) for the Analysis of 2‐ and 4‐Methylimidazole in Cola and Dark Beer

We have developed a simple and fast sample preparation technique in combination with a gas chromatography‐tandem mass spectrometry (GC‐MS/MS) for the quantification of 2‐methylimidazole (2‐MeI) and 4‐methylimidazole (4‐MeI) in colas and dark beers. Conventional sample preparation technique for GC‐MS requires laborious and time‐consuming steps consisting of sample concentration, pH adjustment, ion pair extraction, centrifugation, back‐extraction, centrifugation, derivatization, and extraction. Our sample preparation technique consists of only 2 steps (in situ derivation and extraction) which requires less than 3 min. This method provided high linearity, low limit of detection and limit of quantification, high recovery, and high intra‐ and interday repeatability. It was found that internal standard method with diluted stable isotope (4‐MeI‐d₆) and 2‐ethylimidazole (2‐EI) could not correctly compensate the matrix effects. Thus, standard addition technique was used for the quantification of 2‐ and 4‐MeI. The established method was successfully applied to colas and dark beers for the determination of 2‐MeI and 4‐MeI. The 4‐MeI contents in colas and dark beers ranged from 8 to 319 μg/L and from trace to 417 μg/L, respectively. Small quantity (0 to 8 μg/L) of 2‐MeI was found only in dark beers. The contents of 4‐MeI (22 μg/L) in colas obtained from fast food restaurants were significantly lower than those (177 μg/L) in canned or bottled colas.     

兰州市熟肉制品中亚硝酸盐的使用情况及达标检测现状调研

近年来,在食品中添加非食用物质或滥用食品添加剂而导致群体性食物中毒的恶性事件在我国频频发生。作为消费量占肉类产量60%左右的熟肉制品和肉肠类制品[1]其食用是否安全更是各级政府和广大市民关注的焦点。针对兰州市2001～2005年市售熟肉制品中亚硝酸盐合格率较低[2],2008年其检出率高居不下的状况,文章主要讨论了兰州市售熟肉制品的安全现状及可能出现肉制品安全问题的原因,并在此基础上提出了预防肉制品安全问题产生的相关对策。     

A three-prong strategy to develop functional food using protein isolates recovered from chicken processing by-products with isoelectric solubilization/precipitation

BACKGROUND: Skin‐on bone‐in chicken drumsticks were processed with isoelectric solubilization/precipitation to recover muscle proteins. The drumsticks were used as a model for dark chicken meat processing by‐products. The main objective of this study was conversion of dark chicken meat processing by‐products to restructured functional food product. An attempt was made to develop functional food product that would resemble respective product made from boneless skinless chicken breast meat. A three‐prong strategy to address diet‐driven cardiovascular disease (CVD)with a functional food was used in this study. The strategy included addition of three ingredients with well‐documented cardiovascular benefits: (i) ω‐3 polyunsaturated fatty acid‐rich oil (flaxseed‐algae, 9:1); (ii) soluble fiber; and (iii) salt substitute. Titanium dioxide, potato starch, polyphosphate, and transglutaminase were also added. The batters were formulated and cooked resulting in heat‐set gels. RESULTS: Color (L*a*b*), texture (torsion test, Kramer shear test, and texture profile analysis), thermal denaturation (differential scanning calorimetry), and gelation (dynamic rheology) of chicken drumstick gels and chicken breast gels were determined and compared. Chicken drumstick gels generally had comparable color and texture properties to the gels made from chicken breast meat. The endothermic transition (thermal denaturation) of myosin was more pronounced and gelation properties were better for the drumstick gels. CONCLUSION: This study demonstrated a feasibility to develop functional food made of muscle proteins recovered with isoelectric solubilization/precipitation from low‐value dark chicken meat processing by‐products. The functional food developed in this study was enriched with CVD‐beneficial nutrients and had comparable instrumental quality attributes to respective products made of chicken breast meat. Although the results of this study point towards the potential for a novel, marketable functional food product, sensory tests and storage stability study are recommended. Copyright © 2012 Society of Chemical Industry     

Probiotication of cooked sausages employing agroindustrial coproducts as prebiotic co-encapsulant in ionotropic alginate–pectin gels

Cooked sausages were formulated inoculating alginate–pectin microcapsules containing agroindustrial coproducts, cactus pear peel flour or apple marc flour, seeking to enhance the nutritional value of cooked meat products. The microcapsules increased total moisture (from 66 to 75% in average), but water was not being physically retained since higher expressible moisture values in inoculated samples were observed (20% as compared to 15% in control). Inoculated samples presented higher lactic acid bacteria populations, since in addition to the thermotolerant capacity of the bacteria, encapsulation added a protective barrier for the bacteria to survive. Higher lactic acid bacteria counts were reflected in fewer coliforms in inoculated samples (<0.001 log CFU after 15 days of storage), with no detrimental effect on texture. Natural antioxidants present in agroindustrial coproducts decreased the oxidative rancidity of lipids for storage. The results imply that agroindustrial coproducts are a good alternative to formulate symbiotic functional ingredients that can be employed to improve the nutritional properties of nondairy thermal processed food products, like cooked emulsified meat products.     

多维灰聚类法与定性分析在熟肉制品安全风险 评估中的应用

目的 对2015年某省内生产销售的熟肉制品进行检验,并对检验结果进行安全风险评估。方法 对熟肉制品生产过程中容易出现的风险点进行定性分析, 从而确定熟肉制品的风险因素, 利用多维灰色聚类法对影响食品安全的主要风险因素进行定量评估, 探讨影响熟肉制品有害因素的主次关系。结果 评估结果显示抽检中不合格样品大多属于低风险类, 可以得出熟肉制品的食品安全状况属于安全可控状态。结论 该法明确了食品安全风险的等级, 为食品安全控制做出前瞻性、有效性的技术支撑, 对今后风险评估工作的开展具有切实可行的实践意义。     

基于COI序列的DNA微条形码技术鉴别熟肉制品中11种肉掺假的研究

建立并优化了基于COI序列的DNA微条形码技术(mini-barcoding)检测熟肉制品中11种常见肉类掺假的方法.样品经超声与真空冷冻干燥处理,提取DNA模板和PCR扩增后,目标扩增物经切胶纯化后进行克隆测序,并将测序结果提交GenBank数据库Blast比对.筛选出适合猪、牛、羊、鸡、鸭、鸽子、马、驴、鹅、兔、鼠...     

多维灰聚类分析在熟肉制品安全风险评估中的应用

以某省2011年餐饮服务食品安全抽检数据为基础,采用灰理论对当年餐饮服务环节熟肉制品的食品安全风险程度做出多维灰聚类评估。评估结果显示抽检中不合格样品大多属于低风险类,可以得出当年熟肉制品的食品安全状况属于安全可控状态。该法更加明确了食品安全风险的等级,加强了监管餐饮环节食品安全的有效性,也为今后评估食品安全风险等级提供了一种新的研究方法。     

Assessment of different dietary fibers (tomato fiber, beet root fiber, and inulin) for the manufacture of chopped cooked chicken products

Three dietary fibers (tomato fiber [TF], beet root fiber [BRF], and inulin) at 3 levels of addition (1%, 2%, and 3%) were assessed for the manufacture of chopped, cooked chicken products and compared with a control product without fiber added. The effect of fiber incorporation on (i) batters, (ii) cooked (30 min at 70 °C), and (iii) cooked and stored (for 10 d at 4 °C) chicken products were studied. The addition of the fiber to chicken meat products reduced the pH of chicken batters in proportional to the level of fiber addition. Fiber incorporation increased water-holding capacity but only the addition of TF reduced cook losses. The color of batters and cooked products was significantly modified by the type and level of fiber added. These changes were more noticeable when TF was added. Texture parameters were affected by the incorporation of TF and BRF; they increased the hardness in proportional to the level of addition. The addition of tomato and BRF to chicken meat products reduced lipid oxidation processes. These changes were dependent on the level of fiber added. The reduction of lipid oxidation processes was more marked in TF meat products than in products with other types of fibers. In contrast, the addition level of inulin increased TBA-RS numbers in chicken meat products. Although the addition of TF increased the redness of the meat products, the use of this fiber was more suitable as it reduced the extent of lipid oxidation processes. INDUSTRIAL APPLICATION: Nowadays, the reduction of fat and the increase of fiber content in meat products is one of the main goals of meat industry. Numerous sources of fiber can be added to the meat products; however, before that it is necessary to study their technological effect on raw and cooked meat products in order to evaluate their suitability for meat products manufacture. In addition, some of them could have beneficial effect on meat products conservation that could also increase their shelf life.     

False Positive Detection of Peanut Residue in Liquid Caramel Coloring Using Commercial ELISA Kits

Initial food industry testing in our laboratory using enzyme‐linked immunosorbent assay (ELISA) methods indicated that the darkest caramel color (class IV) unexpectedly contained traces of peanut protein, a potential undeclared allergen issue. Caramel production centers on the heating of sugars, often glucose, under controlled heat and chemical processing conditions with other ingredients including ammonia, sulfite, and/or alkali salts. These ingredients should not contain any traces of peanut residue. We sought to determine the reliability of commercially available peanut allergen ELISA methods for detection of apparent peanut residue in caramel coloring. Caramel color samples of classes I, II, III, and IV were obtained from 2 commercial suppliers and tested using 6 commercially available quantitative and qualitative peanut ELISA kits. Five lots of class IV caramel color were spiked with a known concentration of peanut protein from light roasted peanut flour to assess recovery of peanut residue using a spike and recovery protocol with either 15 ppm or 100 ppm peanut protein on a kit‐specific basis. A false positive detection of peanut protein was found in class IV caramel colors with a range of 1.2 to 17.6 parts per million recovered in both spiked and unspiked liquid caramel color samples. ELISA kit spike/recovery results indicate that false negative results might also be obtained if peanut contamination were ever to actually exist in class IV caramel color. Manufacturers of peanut‐free products often test all ingredients for peanut allergen residues using commercial ELISA kits. ELISA methods are not reliable for the detection of peanut in class IV caramel ingredients and their use is not recommended with this matrix.     

雪茄烟末复合焦甜香料的制备及机制雪茄的应用研究

  目的  为解决机制雪茄香气不足、口感发苦、余味不适的问题,开发一种具有雪茄香韵风格特征、适用于机制雪茄加香的复合焦甜香料。  方法  优化提取溶剂并制备雪茄烟末提取物,将提取物添加于葡萄糖焦糖化反应体系中制备复合焦甜香料,利用GC-MS测试和感官评价阐明反应规律和加香作用特点,并进行制备工艺优化。  结果  （1）雪茄烟末以石油醚提取为优,石油醚提取物的总香味成分含量显著高于无水乙醇和50%乙醇提取物,石油醚有助于雪茄烟末萜烯类和油脂类成分的提取。（2）复合焦甜香料的优选制备工艺为:葡萄糖反应液温度达到180℃时加入石油醚提取物,物料质量比为石油醚提取物: 葡萄糖= 2:10,持续反应3 min。（3）GC-MS分析和感官评价表明,复合焦甜香料主要含有5-羟甲基糠醛（5-HMF）、糠醛、2, 3-二氢-3, 5二羟基-6-甲基-4（H）-吡喃-4-酮（DDMP）等焦甜香韵成分以及烟碱、二氢猕猴桃内酯、新植二烯等烟草本香成分,以焦甜香韵成分为主,其加香效果优于单一的葡萄糖焦甜香料和雪茄烟末石油醚提取物。（4）香气和余味轮廓分析表明,复合焦甜香料能显著增强机制雪茄的焦甜香韵,略微增加清甜、蜜甜和烘烤香,并能明显改善甜润度和刺激感等余味指标。  结论  复合焦甜香料能增加机制雪茄香气量,且能改善余味,适用于机制雪茄加香,优选的添加量为0.4%。      

2010~2016年云南省熟肉制品和餐饮食品中单增李斯特菌污染情况调查分析

目的 了解2010～2016年云南省市售熟肉制品和餐饮食品中单增李斯特菌污染情况调查分析。方法 在全省16个州市县中选取超市、农贸市场、零售及餐饮环节等为采样点, 随机采取熟肉制品1465份和餐饮食品3674份, 按照GB 4789.30-2010《食品安全国家标准 食品微生物学检验 单核细胞增生李斯特氏菌检验》及《全国食源性致病菌监测工作手册》进行检测和鉴定。结果 1465份熟肉制品中单增李斯特菌检出率为2.18%(32/1465), 3674份餐饮食品中单增李斯特菌阳性率为1.44%(53/3674)。在不同流通环节中, 熟肉制品和餐饮制品中检出率最高的分别为便利店和超市, 分别为9.09%(5/55)和1.67%(3/180)。在不同的监测地区, 熟肉制品和餐饮制品检出率最高均为昭通地区, 分别为7.8%(11/141)和7.17%(18/251)。结论 单增李斯特菌在熟肉制品及餐饮食品中均有检出, 说明云南省的食品中存在一定的单增李斯特菌污染, 对消费者的安全有潜在风险, 相关监管部门应持续加强监管, 预防食源性疾病的发生。     

ISO22000食品安全管理体系在熟肉制品中的应用

熟肉制品安全与其在消费环节(由消费者摄入)食源性危害的存在有关。由于在食品链的任何阶段都有可能引入食品安全危害,因此,必需对整个食品链进行充分的控制,熟肉制品安全是要通过食品链中所有参与方的共同努力来保证。熟肉制品安全一直是食品供应链中的一个重要问题,ISO22000:2005《食品安全管理体系—对食品链中任何组织的要求》,为熟肉制品安全管理提供了标准。     

NUMERICAL ANALYSIS OF THE GROWTH OF CLOSTRIDIUM PERFRINGENS IN COOKED BEEF UNDER ISOTHERMAL AND DYNAMIC CONDITIONS1

The main objective of this study was to develop a numerical technique to solve a set of biologically‐based differential equations used to describe the growth behaviors of bacteria under isothermal conditions in food systems. A 4th‐order Runge‐Kutta method was incorporated to a computer program to solve these equations covering the entire range of bacterial growth, including lag, exponential, and stationary phases. The differential growth models were tested using the spores of Clostridium perfringens inoculated to ground beef and incubated under various isothermal conditions between 17–50C. Results of numerical analysis showed that the differential equations could accurately describe the growth of C. perfringens in cooked ground beef under isothermal conditions. The differential equations were also used to estimate the growth of C. perfringens in cooked ground beef under four different dynamic temperature profiles: 2‐square waves, exponential and linear cooling. In combination with a secondary kinetic model, the growth of C. perfringens in cooked ground beef under dynamic conditions was accurately estimated. Results showed the differences between the estimated and experimentally observed growth curves under dynamic conditions were generally less than 0.5 log (CFU/g). The methodology developed in this study can be a new approach for the food industry, food retailers and consumers, and regulatory agencies to predict and estimate the bacterial growth in cooked meat products under dynamic temperature abuse and deviation conditions.     

重庆市即食食品中单核细胞增生李斯特菌污染监测及初步风险评估

目的 了解重庆市市售即食食品中单核细胞增生李斯特菌(以下简称单增李斯特菌)的污染情况,进行初步风险评估,为预防食源性疾病提供科学依据.方法 2016-2019年对全市39个区县的市售即食食品中的单增李斯特菌进行监测,并用半定量微生物风险评估方法,初步评估重庆市即食食品中单增李斯特菌的风险.结果 重庆市2 680份即食食...     

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.