烤牛肉加工工艺

主要介绍了烤牛肉工艺流程、配方和加工要点.     

烧烤牛肉加工工艺

主要介绍了烧烤牛肉工艺流程、配方及操作要点。     

Quantification of character-impact odour compounds of roasted beef

Beef was roasted for 7 min in frying pans made of glass (A) or of stainless steel (B). The lower temperature in A yielded a more roasty-sweet flavour and the higher temperature in B a roasty-harsh, more caramellike flavour. Using stable isotope dilution assays the concentration levels of the odour compounds 4-hydroxy-2,5-dimethyl-3(2H)-furanone (I), 2-acetyl-2-thiazoline (II), 2-ethyl-3,5-dimethylpyrazine (III), 2,3-diethyl-5-methylpyrazine (IV), guaiacol (V) and methional (VI) were determined in samples A and B. The data obtained were divided by the corresponding odour thresholds which were evaluated nasally and retronasally. The results indicated that the flavour differences of A and B were preferentially caused by differences in the concentration levels of odorantsI, II, IV, andVI.

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Quantitative Analyse charakteristischer Geruchsstoffe von gebratenem Rindfleisch

Zusammenfassung Rindfleisch wurde 7 min in Pfannen aus Glas (A) und rostfreiem Stahl (B) gebraten. Die niedrigere Temperatur in A führte zu einem stärker röstig-süßen Aroma und die höhere Temperatur in B zu einem röstig-herben, stärker caramelartigen Aroma. Die Konzentrationen der Geruchsstoffe 4-Hydroxy-2,5-dimethyl-3(2H)-furanon (I), 2-Acetyl-2-thiazolin (II), 2-Ethyl-3,5-dimethyl-pyrazin (III), 2,3-Diethyl-5-methylpyrazin (IV), Guajacol (V) und Methional (VI) wurden in den Proben A und B mit Hilfe von Isotopenverdünnungsanalysen bestimmt. Die erhaltenen Werte wurden dividiert durch die entsprechenden nasal und retronasal ermittelten Geruchsschwellen. Die Ergebnisse zeigten, daß die Aromaunterschiede von A und B in erster Linie auf Unterschiede in den Konzentrationen der GeruchsstoffeI,II, IV undVI beruhen.

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Presented in part at the symposium Flavour Precursors, University of Würzburg, Sept. 30th to Oct. 2nd, 1992     

Evaluation of potent odorants in roasted beef by aroma extract dilution analysis

Summary Aroma extract dilution analysis of the volatile fraction isolated from roasted beef resulted in 25 odour compounds of which 22 were identified. 2-Acetyl-2-thiazoline, furaneol, guaiacol, 2-ethyl-3,5-dimethylpyrazine and 2,3-diethyl-5-methylpyrazine were detected as the character impact compounds for the roasty, caramel-like, burnt and earthy odour notes. (E)-2-Nonenal, (E,E)-2,4-decadienal and -octalactone originated, at least in part, from the fat used for the roasting the meat.

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Ermittlung intensiver Geruchsstoffe in gebratenem Rindfleisch durch Aromaextrakt-Verdünnungsanalyse

Zusammenfassung Die Aromaextrakt-Verdünnungsanalyse von gekochtem Rindfleisch ergab 25 Geruchsstoffe, von denen 22 identifiziert wurden. Die röstigen, caramelartigen, brenzlig und erdigen Geruchsnoten im Aroma wurden vom 2-Acetyl-2-thiazolin, Furaneol, Guajacol, 2-Ethyl-3,5-dimethylpyrazin und 2,3-Diethyl-5-methylpyrazin verursacht. (E)-2-Nonenal, (E,E)-2,4-Decadienal und -Octalacton stammten zumindest zum Teil vom zum Braten verwendeten Fett.

     

Studies in pyrazines formed in roasted spices: Coriandrum sativum,Cuminum cyminum and Trigonella foenum-graecum

Roasted spices are extensively used as flavour enhancers in various curries, sausages and soups. Pyrazines, which are potential flavour enhancers make a substantial contribution. Various pyrazines have been detected in roasted spices viz. coriander, cumin and fenugreek seeds. By employing TLC and DRAGENDORFFS reagent pyrazines could be detected and estimated down to 2.5 and 5 μg respectively. They can be conveniently characterized by their distinct U.V. and I.R. spectra.     

Investigations into flavouring compounds formed in roasted brown mustard (Brassica juncea LINN.)

Roasted brown mustard seeds (Brassica juncea LINN.) form an important condiment. Whereas the flavour of unroasted mustard seed powder is mainly due to isothiocyanates, their roasting brings about changes in its flavour. Twenty four compounds have been identified in roasted mustard which are responsible for its flavour, these include nine carbonyls, six pyrazines, two thiophenes, two amines, one nitrile, two isothiocyanates, one thiocyanate and one alkyl sulphide. The carbonyls were resolved as 2,4-DNP-hydrazones by TLC. The quantity of total carbonyls per 5 kg in roasted mustard was 105 mg as compared to 26 mg in unroasted mustard. Non-carbonyls were separated both by GLC and TLC. By GLC these were characterised by their specific retention times on different columns and on TLC by their R and specific colour reactions. They were further confirmed by their IR spectra. Their quantitative estimation and mechanism of formation is discussed.     

Influence of extra virgin olive oil on the formation of heterocyclic amines in roasted beef steak

In this study, heterocyclic anime (HCA) contents were monitored in commonly consumed pan-fried beefsteak based on the highest level of human exposure. Effect of addition of extra virgin olive oil (EVOO) on HCAs formation in fried beef steaks was evaluated. After EVOO was spread on the meat surface, the raw beef was cooked at 200°C for 5 min on each side. The HCAs were extracted from the meat samples and purified using a solid-phase extraction method and then analyzed by liquid chromatography-mass spectrometry (LC-MS). Among the 15 HCAs, 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido [4,3-b]indole (Trp-P-2), 9H-pyrido [3,4-b]indole (Norharman), 1-methyl-9H-pyrido [3, 4-b]indole (Harman), 2-amino-9H-pyrido [2,3-b]indole (AαC), 2-amino-3-methyl-9H-pyrido [2,3-b]indole (MeAαC), 2-amino-3,8-dimethylimidazo [4,5-f]-quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo [4,5-b]-pyridine (PhIP) were detected in all of the cooked beefsteaks. HCAs formation was significantly reduced (p<0.05) when the EVOO was added to the beef prior to cooking. The addition of 2 and 4 g of EVOO considerably inhibited HCAs formation in the fried beefsteak. However, adding excess amounts of EVOO promoted some HCAs formation.     

Heterocyclic flavour volatiles formed in the basic fraction of roasted phaseolus aureus (Mung dal)

Summary Phaseolus aureus (Mung dal, split and dehusked) after roasting is used as such or in the powder form in both sweet and savoury preparations. Various heterocyclic compounds that constitute the flavour of roasted pulse with and without alkali treatment are reported. Roasting after alkali treatment of the pulse enhances its flavour. The alkali-treated roasted pulse contains 2-methyl-pyridine and nine pyrazines, whereas the untreated roasted has 4-methyl-5-(-hydroxyethyl)-thiazole and six pyrazines.

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Heterocyclische flüchtige Aromastoffe in der Hauptfraktion von gerösteten Phaseolus aureus (Mung dal)

Zusammenfassung Phaseolus aureus (Mung dal, gespalten und enthülst) wird nach dem Rösten entweder als solche verwendet oder in Pulverform, in süßer und pikanter Zubereitung. Verschiedene heterocyclische Verbindungen machen das Aroma der gerösteten Hülsenfrüchte mit oder ohne Alkalibehandlung aus. Das Rösten nach der Alkalibehandlung der Hülsenfrüchte steigert deren Aroma: Die alkalisch behandelte geröstete Hülsenfrucht enthält 2-Methylpyridin und 9 Pyrazine, während die unbehandelten gerösteten 4-Methyl-5(-Hydroxyethyl) und 6 Pyrazine aufweisen.

     

Identification and Maillard reaction activities of dilauryl mannose isomers formed during lipase-catalyzed condensation

Lauryl mannoses were synthesized by lipase-catalyzed condensation using d-mannose and lauric acid in acetone in the presence of molecular sieves at 50 °C. 6-O-Lauryl mannose, 1,6-di-O-lauryl mannose, 3,6-di-O-lauryl mannose, and 4,6-di-O-lauryl mannose were isolated and identified by FT-IR, MS, and NMR.     

New vitamin E isomers (gamma-tocomonoenol and alpha-tocomonoenol) in seeds,roasted seeds and roasted seed oil from the Slovenian pumpkin variety ‘Slovenska golica’

The Štajerska region in north-eastern Slovenia and the Styria region in southern Austria have a long tradition of growing pumpkins (Cucurbita pepo L.) as an oil crop. GC-MS determination of the free and esterified minor compounds in oil of roasted pumpkin seeds from the Slovenian C. pepo L. variety ‘Slovenska golica’ revealed the presence of two previously unreported compounds: alpha-tocomonoenol and gamma-tocomonoenol. Using the GC-MS data, reference samples (Crude Palm Oil) and tocopherol and tocotrienol standards it was possible to assign and quantify alpha-tocomonoenol (17.6 ± 0.6 μg/g) and gamma-tocomonoenol (118.7 ± 1.0 μg/g) compounds in roasted ‘S. golica’ seed oil using HPLC. The concentrations of alpha-tocopherol and gamma-tocopherol were 77.9 ± 1.9 μg/g and 586.0 ± 4.6 μg/g, respectively. Surprisingly the gamma-tocotrienol concentration found was only 6.9 ± 0.2 μg/g. Analysis of the seeds from which the oil was pressed showed the initial gamma-tocotrienol amount was even lower (1.6 ± 0.1 and 2.2 ± 0.1 μg/g in the ground and roasted seeds, respectively) than in the roasted seed oil.     

Detection of ground roasted coffee adulteration with roasted soybean and wheat

Coffee as high-price commodity is quite vulnerable to adulteration by cheaper roasted grains. Frauds are conventionally detected by microscopy; however, this technique is limited semi-quantitative assays that require training and skilled analysts. In this regard, carbohydrates as major macronutrients of grains can be used as chemical markers to qualitatively and quantitatively assess coffee authenticity. Although, some tamper's studies have already been reported, this paper approaches on new analytical resources for detection of ground roasted coffee adulteration, applying roasted soybean and wheat as sources of fraud. The characterization of the pure roasted coffee beans and of adulterations profiles was taken by total carbohydrates validated method based on high-performance anion-exchange chromatography with pulsed amperometric detection. The influence of each matrix was evaluated employing the simplex-centroid design for experiments with mixtures thus relating the mixing ratio with each monosaccharide by response surface. The proposed models were effective in recognition and prediction of different mixture proportions, thereby allowing the distinction of genuine coffee by principal component analysis and linear discriminant analysis. Predominantly, pure roasted coffee presented higher levels of galactose and mannose. Glucose can be considered as a marker for wheat adulteration and fructose for soybean, respectively. These results correspond to polysaccharides of pure raw grains, confirming this approach as a feasible analytical tool for detection of adulterants in ground roasted coffee.     

Effects of incorporating roasted lupin (Lupinus angustifolius) flour on the physicochemical and sensory attributes of beef sausage

The effects of incorporating lupin flour on the physicochemical and sensory characteristics of beef sausages were explored. Lupin (Lupinus angustifolius) flour was roasted, then hydrated to match the moisture content of beef meat. The beef sausage samples were manufactured for six treatments by replacing beef with hydrated lupin flour from 0% to 36% (w/w). Proximate analysis revealed that carbohydrate (dietary fibre) level was increased from 9.62% to 19.31%, whereas fat content was decreased from 11.62% to 7.91%. Inclusion of lupin flour increased the meat emulsion stability (fluid released decreased from 9.35% to 1.53%) and decreased cooking loss from 22.70% to 14.30%. Softer texture and greater adhesiveness were observed in lupin-incorporated formulations. Sensory evaluation indicated no significant difference between control and 12% lupin-enriched beef sausage formulation in appearance, aroma, flavour and overall liking, suggesting lupin flour can be added to beef sausage at this level without compromising consumer acceptance.     

Influence of growth promoting implants on fatty acid composition including conjugated linoleic acid isomers in beef fat

The influence of the growth promoting implants Synovex (SYN), Ralgro (RAL), and Revalor (REV) on the fatty acid profiles of subcutaneous fat, intramuscular fat, and phospholipids of 32 beef steers (eight steers per treatment, and eight controls) was studied. Fatty acid compositions and profiles of conjugated linoleic acid (CLA) isomers were determined by a combination of GC and triple-column Ag⁺-HPLC. Only small differences could be observed between the different treatment groups. The amount of saturated fatty acids relative to monounsaturated fatty acids was increased by all growth promoting implants in subcutaneous fat (P<0.1) and also by SYN in intramuscular fat. RAL led to slightly higher amounts of trans fatty acids in subcutaneous and intramuscular fat (P<0.1). REV-implanted steers showed some significant differences in their profiles of polyunsaturated fatty acids compared to control steers. CLA content and isomeric distribution in subcutaneous fat were affected bySYN, which reduced amounts of total CLA (0.42 mg/g fat vs. 0.53 mg/g in control steers, P<0.001) and decreased the proportions of the primary 18:2 c9t11 isomer (73% of total CLA for SYN vs. 77-78% for all other treatment groups). Slight increases of c9t11 CLA in intramuscular fat were observed in RAL- and REV-implanted steers (P<0.1). Most differences in fatty acid composition observed in this study were probably due to shifts in the storage lipid/membrane lipid ratio.     

The species-specific ratios of 2,3-butanediol and acetoin isomers as a tool to evaluate wine yeast performance

The isomers of 2,3-butanediol [R,R; S,S; R,S (meso-form)] and of acetoin (R,S) were determined in laboratory wine fermentations carried out by 50 yeast strains, 10 for each of the following species, Saccharomyces cerevisiae, Kloeckera apiculata, Candida stellata, Metschnikowia pulcherrima and Brettanomyces bruxellensis, in order to evaluate if such parameters might be used to differentiate wines obtained with different yeast species. According to analysis of variance (ANOVA), the strains of the same species behaved similarly, whereas the five yeast species behaved differently so that species-specific profiles were recognized. Moreover, the discriminant analysis grouped the wines into five groups, each including the 10 wines obtained by the 10 yeast strains of the same species. Trials were also included where musts partially fermented by non-Saccharomyces species were inoculated with a selected strain of S. cerevisiae to complete fermentation, and the content in 2,3-butanediol and acetoin isomers was again determined and statistical analysis was performed. Although the final values of these parameters resembled those obtained in pure fermentation with S. cerevisiae, statistical analysis discriminated wines according to the yeast species performing the first fermentation phase.     

Characterization of the key aroma compounds in roasted duck liver by means of aroma extract dilution analysis: comparison with beef and pork livers

By application of the aroma extract dilution analysis (AEDA) on the volatile fraction isolated by solvent extraction and solvent-assisted flavour evaporation from roasted duck liver, thirty odour-active areas could be detected in the flavour dilution factor (FD) range of 16–2,048. The highest FD factors were found for 2-acetyl-1-pyrroline (roasty, popcorn-like), 2-acetyltetrahydropyridine (roasty), and 2-acetyl-2-thiazoline (roasty), followed by 2-furfurylthiol (roasty, coffee-like) and 3-methylthio(propanal) (cooked potato) with slightly lower FD factors of 1,024. Application of the AEDA on the volatiles isolated from roasted pork and beef livers revealed basically the same set of odorants in about the same range of FD factors in both livers. A main difference, however, was the comparatively low FD factor of 2-acetyltetrahydropyridine in beef and pork livers indicating that this roasty smelling odorant might be responsible for the difference detectable in the overall aroma of duck liver. In total, 15 odorants were identified for the first time in liver.     

5-降冰片烯-2,3-二羧酸单甲酯的合成与表征

以5-降冰片烯-2,3-二酸酐(NA)和甲醇为原料,正交试验法合成了5-降冰片烯-2,3-二羧酸单甲酯(NE),并对产物结构进行了表征.实验确定的最佳工艺条件为:V(甲苯)=55 mL,n(NA):n(甲醇)=1,回流反应4 h.在此条件下,NE的产率可达86.2%.表征结果表明,产品结构与目的产物的结构完全一致.     

Ochratoxin A in Brazilian roasted and instant coffees

Thirty-four samples of roast and ground coffee, 14 samples of instant coffee and two samples of decaffeinated instant coffee were collected in markets and supermarkets in the city of Campinas, Brazil, and analysed for ochratoxin A using immunoaffinity columns for clean-up and HPLC with fluorescence detection for quantification. The limit of detection was 0.2 ng/g ochratoxin A. Twenty-three samples of ground and roast coffee were found to be contaminated with the toxin at levels ranging between 0.3 and 6.5 ng/g. The average concentration in all 34 samples was 0.9 ng/g. All samples of instant coffee contained ochratoxin A at levels ranging from 0.5 to 5.1 ng/g, with an average figure of 2.2 ng/g. Roast and ground coffee is the type of coffee most used by Brazilians for the preparation of the beverage. Considering that an average Brazilian adult takes five cups of coffee per day, which corresponds to 30 g of roast and ground coffee, the probable daily intake of ochratoxin A by a 70 kg adult would be 0.4 ng/kg bw, which is far below the current Provisional Tolerable Daily Intake of 14 ng/kg bw for ochratoxin A as set by the Codex Alimentarius. To study the transfer of ochratoxin A into coffee brew, the beverage was prepared by two methods: (a) the drip method and (b) the Brazilian country style method. No significant difference was observed between the two methods in terms of extraction of the toxin using five contaminated samples containing between 0.8 and 6.5 ng/g ochratoxin A. The drip method extracted 86 +/- 15% and the Brazilian country style 74 +/- 20% of the ochratoxin A initially present in the roast and ground coffee.     

Effect of the roasting method on the content of 5-hydroxytryptamides of carboxylic acids in roasted coffee beans

Coffee beans of Coffea liberica (robusta) variety were roasted using convection and microwave heating. For roasting we used green coffee beans of 7.5% moisture content, and beans wetted to 10% moisture content and dried to 5% moisture content. The content of 5-hydroxytryptamides of carboxylic acids C-5-HT (determined by TLC) as the index of substances irritating alimentary canal was investigated in the roasted beans, depending on the bean treatment before roasting and applied roasting method. Analytical results show that predrying of the coffee beans caused 15-30% loss of C-5-HT, depending on the applied drying conditions. The content of C-5-HT in the roasted beans depended on the roasting method and preliminary treatment of the beans prior to roasting. A higher C-5-HT loss occurred in the case of beans subjected to two-stage processing, predrying and roasting. Convection roasting caused higher degradation of C-5-HT than microwave roasting.