几种天然香辛料提取物延长冷却肉货架期的研究

以冷却肉为试验材料,研究肉桂、丁香、迷迭香3种天然香辛料的保鲜效果.分别采用不同浓度的3种香辛料提取物对冷却肉进行单因素试验,测定第0,7,14,21天的细菌总数、metMb百分含量、pH值等指标.结果表明:肉桂、丁香、迷迭香的醇提液浓度分别为2.0,2.0,1.5 g/L时,对冷却肉具有良好的保鲜效果,在第21天时,冷却内的细菌总数、metMb百分含量、pH值各指标均处于鲜肉水平.     

天然物质对广式腊肉贮存期间酸价的影响

为了研究植物多酚提取物、植物皂甙、VC、VE和肌肽等几种天然物质对广式腊肉储藏中酸价的影响,结果显示肌肽能够最为显著地抑制腊肉中酸价升高。通过研究各种物质对腊肉中储藏过程中性脂肪酶、酸性脂肪酶、磷脂酶的抑制作用,初步阐明天然物质对广式腊肉酸价抑制的机理。结果表明,在检测的多种物质中,多酚提取物对磷脂酶活力抑制效果不明显,在储藏前3周对中性脂肪酶显示出较强的抑制效果,在储藏前5周对酸性脂肪酶有显著的抑制效果。三种皂苷提取物对不同脂肪酶抑制效果有显著差异,其中绞股蓝提取物对三种脂肪酶都有一定的抑制效果,而人参和西洋参提取物对磷脂酶和中性脂肪酶抑制效果不显著。肌肽能够显著抑制腊肉中三种酯质水解酶的活性,因此能够较好地控制腊肉的酸价。     

Effect of ground poppy seed as a fat replacer on meat burgers

Poppy seed paste was used in koefte production as an animal fat replacer and efficacy of using poppy seed was investigated. The use of ground poppy seed in formulation of meat burgers had no effect on the moisture content of uncooked meat burgers; however, it did have a significant effect (p<0.05) on the fat content of meat burgers. Ground poppy seed addition significantly affected (p<0.05) cooking yield, moisture retention, and fat retention of meat burgers. Ground poppy seed addition significantly decreased (p<0.05) saturated fatty acid contents as the amount of ground poppy seed increased in meat burgers. A strong significant decrease (p<0.05) on the cholesterol content of meat burgers with ground poppy seed addition was observed. Samples having 20% ground poppy seed had significantly better texture and juiciness score (p<0.05) than any other sample which could be explained by increased moisture retention. Replacing animal fat with ground poppy seed paste is effective and may pave the way for an innovative meat product.     

天然调味香料高良姜挥发油的研究进展

高良姜是一种常见的食用香料,在食品、医药以及保鲜贮藏上有广泛的应用。文章综述了高良姜挥发油的化学成分、提取方法、生物活性,并对其应用前景进行了展望。     

Effect of inulin on the textural and sensory properties of mortadella, a Spanish cooked meat product

Inulin is a fructooligosaccharide with demonstrable beneficial effects on health. Its effect on the textural and sensory properties of mortadella, a Spanish cooked meat product, was studied. Conventional (23% fat) and reduced‐fat sausages (10% fat) were prepared. Fat reduction yields an energy value reduction close to 33%. In both cases, inulin was incorporated, in powder and as gel form, in sufficient amounts to constitute the 2.5%, 5% and 7.5% of the final product. To evaluate the effect of inulin, instrumental measures of texture and sensory analysis (hedonic test) were performed. Textural analysis indicated that powdered inulin increases hardness and this fact was more evident in reduced‐fat sausages which showed that this changes even at concentrations of 2.5%. However, when inulin was incorporated as a gel, textural parameter changed only when the high levels were assayed (7.5%) showing softer sausages independent of the fat content. Sensory analysis was highly favourable and the overall acceptability was good in all batches in spite of the changes observed in texture. It can be established that this product can be enriched with inulin to a maximum level of 7.5% and preferably as gel with a good sensory quality.     

Effect of antimicrobial spice and herb extract combinations on Listeria monocytogenes, Staphylococcus aureus, and spoilage microflora growth on cooked ready-to-eat vacuum-packaged shrimp

Two spice and herb extract combinations from galangal (Alpinia galanga), rosemary (Rosmarinus officinalis), and lemon iron bark (Eucalyptus staigerana) were evaluated for their ability to inhibit the growth of inoculated Listeria monocytogenes and Staphylococcus aureus and naturally present spoilage microflora on cooked ready-to-eat shrimp stored for 16 days at 4 or 8 °C. A combination of galangal, rosemary, and lemon iron bark significantly reduced (P < 0.05) levels of aerobic bacteria and lactic acid bacteria at 4 °C on day 12 by 1.6 and 1.59 log CFU/g, respectively. By day 16, levels of these bacteria were equivalent to those of controls. The shrimp treated with this spice and herb extract combination had significantly lower (P < 0.05) lipid oxidation from day 4 to day 16. Similarly, a combination of galangal and rosemary extract significantly reduced (P < 0.05) levels of aerobic bacteria and lactic acid bacteria at 8 °C on day 8 by 2.82 and 2.61 log CFU/g, respectively. By days 12 and 16, levels of these bacteria were equivalent to those of controls. The shrimp treated with this spice and herb combination had significantly lower (P < 0.05) lipid oxidation on days 4 and 16. None of the spice and herb extract combinations had an effect on levels of L. monocytogenes or S. aureus or changed the color or pH of the shrimp during storage. The results of this study indicate that combinations of galangal, rosemary, and lemon iron bark extracts can be used to control the growth of spoilage microflora on ready-to-eat shrimp.     

Effect of carnosine preblending on the quality of ground buffalo meat

A study was conducted on carnosine preblending at 0%, 0.5%, 1.0% and 1.5% levels with ground buffalo meat obtained from spent, adult, male Murrah buffalo carcasses, to identify the level of carnosine required for improving the quality of the meat during refrigerated storage at 4 ± 1 °C. It was observed that meat samples containing 1.0% and 1.5% carnosine significantly inhibited metmyoglobin formation and brown colour development. Carnosine also improved meat pH, and water-holding capacity and lowered cooking loss and 2-thiobarbituric acid-reacting substances (TBARS) values as compared to control sample. Carnosine also improved desired visual colour and odour, and gave higher LTCU ‘R’ and chroma of meat samples. Visual colour was inversely correlated with metmyoglobin, aerobic mesophiles and psychrotrophs plate count, and odour was inversely correlated with TBARS values. Use of 1.0% carnosine for preblending extended the shelf life of ground buffalo meat up to 8 days under refrigerated storage.     

天然调味香料月桂精油化学成分的研究

采用水蒸气蒸馏法提取了调味香料月桂的精油,并利用气相色谱/质谱(GC/MS)联用技术和保留指数比较法分析了该精油的化学成分.从月桂的精油中鉴定了44种化合物,占精油总量的99.97％.主要成分为α-乙酸松油酯(19.52％)、肉桂醛(8.00％)、β-按叶油醇(6.18％)、β-石竹烯(5.72％)和丁香酚甲醚(5.25％).     

几种因素对肉制品质构测定结果的影响

采用物性仪对肉制品的质构进行分析(TPA),探讨测定条件对测定结果的影响。通过数据分析得出如下结论:测前速度和两次压缩之间的间隔时间对测定结果的影响不显著;测试速度对硬度、咀嚼性和回弹性都有非常显著的影响,而对弹性和内聚性无显著影响。在测试条件下,硬度和咀嚼性和回弹性均随测试速度的增加呈上升趋势;压缩比例对测定结果都有非常显著的影响,其中硬度和咀嚼性随压缩比例的增加而增加,而弹性、内聚性,回弹性随压缩比例的增加而减少。     

Development of a long‐life vacuum‐packaged ready‐to‐eat meat product based on a traditional Portuguese seasoned meat

Carne do alguidar is a Portuguese traditional pork fried meat, usually manufactured for self‐consumption purposes. This study developed a ready‐to‐eat (RTE) meat product, to meet today's consumers’ convenience, manufactured at the industrial scale evaluating its quality and shelf life, assessing the effect of vacuum packaging and the use of an antioxidant (50 ppm BHT) to enhance oxidative stability. Physicochemical and microbiological parameters were assessed, and a sensory analysis was performed. Interestingly, no significant differences were recorded between control (non‐BHT) and antioxidant (BHT) samples. Microbiological counts remained at low levels throughout the storage period, ensuring the product's required microbiological quality. At later storage stages, higher values of thiobarbituric acid‐reactive substances arose and off flavours and aromas were perceived. Still, overall appreciation was not affected until 12 months of storage and a significant depreciation was perceived only after 15 months. Fibrousness and rising of off flavours were negatively correlated with overall appreciation.     

Influence of nitrite addition and gas permeability of packaging film on the microflora in a sliced vacuum-packed whole meat product under refrigerated storage

Three batches of cured, smoked and cooked pork loins were prepared without nitrite and with 100 or 200 ppm nitrite. The product was sliced, vacuum packed and stored at 2°C, 5°C and 10°C. Part of the product was packed in a conventional film, a polyamide/polyethylene film, and part of it in two films with lower gas permeabilities. Nitrite inhibited the growth of Brocothrix thermosphacta and Enterobacteriaceae at all temperatures. This resulted in a lower growth rate and/or lower maximum counts. Reducing the gas permeability of the film in the absence of nitrite did not influence the growth of B. thermosphacta. An effect of increasing anaerobic conditions was, however, seen in conjunction with 100 pprn added nitrite at both 5°C and 10°C. The Gram-positive cocci were not affected by the addition of nitrite but were soon overgrown by the competing flora. The insensitivity of the lactic-acid bacteria to nitrite and microaerophilic conditions resulted in these bacteria constituting a larger proportion of the total flora in batches with nitrite and/or packaging films with reduced oxygen permeabilities.     

可食天然复合保鲜膜对低温肉制品的保质研究

利用可食性胶原蛋白和壳聚糖与乳酸链球菌素(Nisin)等制成的天然复合保鲜膜对低温肉制品进行浸渍、杀菌、真空包装等处理后,分别置于微温(30~40℃)、常温(20~25℃)、冷藏(0~4℃)3种不同温度条件下贮藏,测定不同贮藏期菌落总数、TVB-N、H2S等指标及感官评定。结果表明,Ⅰ组(2%胶原蛋白 0.05%Nisin 0.03%VE 0.25%茶多酚)和Ⅱ组(2%胶原蛋白 2%壳聚糖 1%醋酸 0.05%Vc 0.03%烟酰胺)的复合保鲜膜处理,其保质期均优于对照组。在微温条件下,Ⅰ、Ⅱ组的保质期分别达30、40d,比对照分别延长10、20d;常温下Ⅰ、Ⅱ组的保质期分别达120、150d,分别比对照延长60、90d;经冷藏的Ⅰ、Ⅱ组保质期均为240d,比对照组延长90d。综合评价以Ⅱ组略好。     

Effect of radio frequency cooking on the texture, colour and sensory properties of a large diameter comminuted meat product

Radio frequency (RF) cooking is a form of dielectric heating similar to microwave heating. In this study an optimised cooking protocol was developed for pasteurising 1 kg cased meat emulsion samples, which were immersed in 80 °C circulating water during cooking. Subsequently, selected quality attributes of RF pasteurised samples were compared to steam pasteurised samples, by instrumental and sensory methods. Instrumental assessments show that RF heated meat batters had a greater ability to hold water, were significantly harder, chewier and gummier (P<0.001), while having less cook colour development than their steam cooked counterparts. Differences were also detected by sensory methods. In conclusion, while differences were detected, it is possible that these could be eliminated by adjusting the cooking protocol to produce similar cook values in RF samples to those in products cooked by steam.     

Predictive models for growth of Salmonella typhimurium DT104 from low and high initial density on ground chicken with a natural microflora

A single strain (ATCC 700408) of Salmonella typhimurium DT104 was used to investigate and model growth from a low (1.12 log10 mpn g(-1)) and high (3.7 log10 cfu g(-1)) initial density on ground chicken with a natural microflora. Kinetic data for growth of the pathogen on ground chicken were fit to a primary model to determine lag time (lambda), maximum specific growth rate (mu) and maximum population density (Nmax). Secondary models for lambda, mu and Nmax, as a function of temperature (10-40 degrees C), were developed and compared among initial densities. Variation of pathogen growth among replicates (n=4 or 5) was higher at 10-18 degrees C than at 22-40 degrees C and was higher for Nmax than lambda and mu. Prediction problems were observed when secondary models developed with one initial density were used to predict lambda, mu and Nmax from the other initial density, especially at 10-18 degrees C and for Nmax. These results indicated that variation of growth among replicate challenge studies and initial density are important factors to consider when developing predictive models for growth of S. typhimurium DT104 on ground chicken with a natural microflora.     

调味香料马玉兰挥发油化学成分的研究

采用水蒸气蒸馏法提取了调味香料马玉兰的挥发油,并利用气相色谱/质谱(GC/MS)联用技术和保留指数比较法分析了该挥发油的化学成分。从马玉兰挥发油中鉴定了40种化合物,占挥发油总量的95.06%。我国马玉兰挥发油的主要成分为4-萜品醇(33.00%)、氧化石竹烯(11.91%)、对伞花烃(6.84%)、α-松油醇(6.66%)和斯巴醇(6.00%)。     

Effect of storage temperatures and time on shelf‐life of sliced and modified atmosphere packaged Pastırma,a dried meat product,produced from beef

The effects of modified atmosphere on some physical, chemical and microbiological properties of sliced past?rma made from beef Longissimus dorsi muscle were investigated. Sliced‐past?rma samples (moisture 43.65 ± 0.15%, pH 5.71 ± 0.02) were stored in modified atmosphere packages (50% N₂ + 50% CO₂) at 4 and 10 °C for 150 days. The storage period had a significant effect (p < 0.01) on moisture, pH, thiobarbituric acid reactive substances, free fatty acid, non‐protein nitrogen, water‐soluble nitrogen, colour values and total aerobic bacteria, lactic acid bacteria and Micrococcus/Staphylococcus counts. The storage temperatures (4 and 10 °C) also had a significant effect (p < 0.01) on moisture, pH, thiobarbituric acid reactive subctances, free fatty acid, water soluble nitrogen, a* values, total aerobic bacteria lactic acid bacteria, and Micrococcus/Staphylococcus counts. It was determined that the storage period × the storage temperature interactions had a significant (p < 0.01) effect on the values of pH, a* and the counts of total aerobic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus. It was also observed that the yeast and mold count was the highest in the first storage period and decreased throughout storage. Enterobacteriaceae count was also below the detectable level (<2.00 cfu g^?1) throughout the storage period. Copyright © 2005 Society of Chemical Industry     

Proteolytic and lipolytic modifications during the manufacture of dry-cured lacón,a Spanish traditional meat product: Effect of some additives

The extractability of sarcoplasmic and myofibrillar proteins, the myofibrillar proteins and their degradation products, classical nitrogen fractions, free amino acids, acidity of the fat, and free fatty acids were determined throughout the manufacturing process of dry-cured lacón, a traditional dry-salted and ripened meat product made in the northwest of Spain from the foreleg of the pig, following a similar technological process to that of dry-cured ham. The effect of the use of additives (glucose, sodium nitrite, sodium nitrate, sodium ascorbate and sodium citrate) on the proteolytic and lipolytic changes was also studied.     

Effect of various chemical decontamination treatments on natural microflora and sensory characteristics of poultry

Regulation (EC) No. 853/2004 of the European Parliament and of the Council provides a legal basis permitting the use of antimicrobial treatments to remove surface contamination from poultry. This paper reports the results of research into the effects on natural microflora, pH, and sensorial characteristics achieved by dipping chicken legs (15 min, 18+/-1 degrees C) into solutions (wt/vol) of 12% trisodium phosphate (TSP), 1200 ppm acidified sodium chlorite (ASC), 2% citric acid (CA), 220 ppm peroxyacids (Inspexx 100; PA), and water. Samples were collected immediately after evisceration, subjected to the treatments listed or left untreated (control) and tested after 0, 1, 3 and 5 days of storage (3 degrees C+/-1 degrees C). For most microbial groups similar counts were observed on water-dipped and on untreated legs. All the chemical compounds were effective in reducing microbial populations throughout storage, with TSP, ASC and CA showing the strongest antimicrobial activity. The average reductions (mean+/-standard deviation) relative to untreated samples caused by chemical treatments when considering simultaneously all storage days ranged (log(10) cfu/g skin) from 0.53+/-0.83 (PA) to 1.98+/-0.62 (TSP) for mesophilic aerobic counts, from 0.11+/-0.89 (PA) to 1.27+/-1.02 (CA) (psychrotrophs), from 1.34+/-1.40 (PA) to 2.15+/-1.20 (CA) (Enterobacteriaceae), from 1.18+/-1.24 (PA) to 1.98+/-1.16 (CA) (coliforms), from 0.66+/-0.99 (PA) to 1.86+/-1.80 (TSP) (Micrococcaceae), from 0.54+/-0.74 (TSP) to 2.17+/-1.37 (CA) (enterococci), from 0.72+/-0.66 (TSP) to 2.08+/-1.60 (CA) (Brochothrix thermosphacta), from 0.78+/-1.02 (PA) to 1.99+/-0.96 (TSP) (pseudomonads), from 0.21+/-0.61 (PA) to 1.23+/-0.60 (TSP) (lactic acid bacteria), and from 1.14+/-0.89 (PA) to 1.45+/-0.61 (ASC) (moulds and yeasts). The microbial reductions throughout storage increased, decreased, or did not vary, in accordance with microbial group and chemical involved. Similar pH values were observed for untreated samples and for those dipped in PA and water on all sampling days. ASC-treated samples showed a lower pH than controls to day 1. TSP-treated legs exhibited the highest pH values and CA-treated ones the lowest, throughout storage. Hedonic evaluation (nine-point structured scale, untrained panellists) showed similar colour, smell and overall acceptability scores for dipped and untreated samples on day 0 and day 1. From day 3 sensorial attributes scored lower for untreated, PA- and water-dipped legs, as compared to legs treated with TSP, ASC and CA. Only for these three groups of samples were average scores higher than 6 (shelf-life limit value) observed by the end of storage. Results from the present study suggest that the treatments tested improve the microbial quality of chicken without adverse sensorial effects.     

天然香料锡兰香茅挥发油抗氧化活性研究

天然调味香料锡兰香茅利用水蒸气提取挥发油过程中,挥发油在前10 min呈无色透明状,10~120 min呈黄色。GC/MS分析显示其成分有较大差异。本实验从总体抗氧化能力、清除羟基自由基能力、清除超氧阴离子自由基能力等三个方面测定所得挥发油抗氧化能力,并与合成抗氧化剂没食子酸丙酯(PG)作比较。实验结果表明,一定浓度范围内,精油总抗氧化和清除羟基自由基能力略低于PG;但清除超氧阴离子方面,锡兰香茅挥发油强于PG,表明锡兰香茅挥发油具有良好抗氧化效果。     

On-line, proximate analysis of ground beef directly at a meat grinder outlet

The fat, moisture and protein contents of ground beef were determined on-line by a diffuse reflectance near infrared (NIR) spectroscopy instrument at the outlet of a meat grinder. Beef samples in the range of 6.2–21.7% fat, 59.6–72.9% moisture and 18.1–20.7% protein were studied. Calibrations from samples ground with hole diameters of 4, 8, 13 or 19 mm in the grinder plate were validated. In addition, calibrations of combinations of these samples from the different hole diameters were validated. Prediction errors, expressed as root mean square error of cross validation of the beef samples, were 0.73–1.50% for fat, 0.75–1.33% for moisture and 0.23–0.32% for protein, depending on the hole diameter of the grinder plate. Calibrations from samples ground with the smallest hole diameters gave lowest prediction errors. The present prediction error results are only slightly higher compared to reported prediction error results using conventional at- and off-line NIR instruments.

It is concluded that the on-line NIR prediction results were acceptable for samples ground with grinder plates of 4, 8 or 13 mm hole diameter.