QUALITY ATTRIBUTES OF GROUND BEEF ON THE RETAIL MARKET

Each of three ground beef products, varying in price (based on lipid content) were purchased from each of three retail stores. Patties of each product were modified broiled at 177°C for 35 min. Products containing 10–20% lipid had less cooking loss than those containing 25–30% lipid, but lower-lipid, higher-priced beef cost more per 100g of cooked meat than higher-lipid, lower-priced beef. Percentage ether extract decreased after broiling raw ground beef containing 20–30% lipid, and increased slightly after broiling raw ground beef containing less than 12% lipid. Over-all acceptability was similar for all three products, but the leanest, highest-priced product rated less juicy, more mealy and lower in flavor than higher-lipid, lower-priced products.     

THE INFLUENCE OF SALT AND HYDROLYZED VEGETABLE PROTEIN ON THE SENSORY ATTRIBUTES OF GROUND COW BEEF PATTIES

Ground cow beef was formulated to contain NaCl (0%, 1% or 2%) and hydrolyzed vegetable protein (0%, 0.25%, 0.50% or 0.75%) and was made into patties. Cow beef and steer beef patties without salt or HVP were utilized as controls. Patties were evaluated for fat and moisture content and sensory attributes. Meat source had no significant effect on fat and moisture content or on sensory attributes. The addition of NaCl resulted in patties that were more juicy, more tender and more desirable in flavor and texture than the control patties. Sensory ratings increased as the level of added salt increased. Patties containing 0.25% hydrolyzed vegetable protein were more tender, more juicy and received higher texture and flavor desirability ratings than patties containing 0%, 0.50% or 0.75% hydrolyzed vegetable protein.     

INFLUENCE OF ODOR SOURCES ON THE ODOR AND FLAVOR OF BEEF

Research was conducted to determine the influence of odor sources present in the vicinity of meat during slaughter, storage, shipping and handling, on the odor and flavor of beef. In most cases, outside samples and ground composites scored higher in off-flavor intensity than did inside samples. Fat sample results were similar but exhibited greater variation. Odor scores followed a similar pattern. Ammonia was found the easiest source of odor and flavor to detect; cigarette smoke, butts and ashes, automobile exhaust, kerosene and paint were also easily detected. Spoiled meat could be detected as imparting an off-odor and off-flavor, but the source was not easily identified. Other variables (e.g., silage, soap, rancid grease) showed little evidence of causing off-flavor or off-odor to the meat. The influence of storage time and exposure pre- or post-rigor seemed negligible in most cases.     

采用质构仪分析氯化钙对牛肉品质的影响

CaCl2对牛肉的嫩化作用多通过感官评定,评定结果存在较多主客观影响因素.采用质构仪测定代替感官评价,测定经CaCl2处理后牛肉的食用物理特性--嫩度、硬度、弹性、胶性和咀嚼性等,可增加评定的合理性.用质构仪穿刺法和质地多面分析(TPA)试验法,对不同部位的牛肉注射不同浓度、不同量CaCl2后的品质进行分析.结果表明,使肉的综合品质较好的较优参数组合为A3、B2、C3,即牛条形腰肉注射5%的浓度为300 mmol/L的氯化钙溶液.其中牛肉的不同部位影响最大,氯化钙溶液的注射量次之,氯化钙溶液的浓度影响较小.     

THE INFLUENCE OF CONDITIONING ON LAGER BEER QUALITY

The relative contributions to lager beer quality of malt, conditioning, and other parts of the brewing process have been assessed by analytical and sensory evaluation. Backed beers, brewed and fermented under various conditions, were stored at temperatures of 12°C, 4°C or 0°C for periods ranging from 2 to 38 days before filtration and bottling. No evidence could be found to justify a need for long periods of beer storage. Although prolonged storage can provide a remedial process, correcting aspects of beer quality such as diacetyl levels, final gravity, and removal of ‘young beer’ flavour, all these features can be more rapidly, effectively and economically controlled by closer attention to materials quality and primary fermentation procedure.     

THE INFLUENCE OF HIGH INTENSITY ULTRASOUND BATHS ON ASPECTS OF BEEF TENDERNESS

Beef Longissimus thoracis et lumborum ( LTL ), Semimembranosus (SM) and Biceps femoris (BF) steaks were sonicated using three commercially available ultrasonic baths of different intensities. The effect of ultrasound on the tenderness of these steaks was examined using peak load bite force tenderometry. Collagen solubility and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) analysis were also conducted on samples of BF and LTL exposed to the most intensive of the ultrasound treatments. Peak force values were not affected by ultrasound treatment (P≤ 0.05). Collagen solubility of LTL or BF did not differ (P ≤ 0.05) between ultrasonicated meat and controls. Similarly, SDS PAGE of myofibrillar proteins showed no differences between control and treated samples in the rates of appearance/disappearance of characteristic aging bands or in the numbers of bands observed on the gels suggesting no obvious effect on myofibrillar proteolysis. It is concluded that under the conditions of treatment employed high intensity ultrasound applied to intact beef steaks had no beneficial effect on meat tenderness. This is in contrast to tenderizing effects reported by other workers with more intensive treatments.     

THE INFLUENCE OF COOKING METHOD ON THE QUALITY OF PORK PATTIES

Pork patties were subjected to traditional frying, cooking in a microwave oven (microwaves  +  grill), hot air cooking in a cyclojet (Electrim JI-9101 RP, Taiwan) and cooking in a steam-convection (combi) oven (hot air  +  30% steam) (BECK FCV 4 EDS, BECK GmbH, Jagsthausen, Germany). Products cooked in the combi oven (BECK FCV 4 EDS) were characterized by the smallest cooking loss, the highest retention of water and the lowest content of fat compared to other samples. The content of hydroxymethylfurfural in fried and cyclojet-cooked patties was almost twofold higher than in microwave and combi oven-cooked samples. The intensity of lipid oxidation was also higher in fried and cyclojet-cooked meat than in the other two products. The intensity of meat flavor was the strongest in the combi oven-cooked patties. All products were characterized by a low intensity of fatty flavor. The highest scores for overall acceptability were given to the combi oven-cooked patties, whereas the lowest scores were given by the panelists to the microwave-cooked patties.

PRACTICAL APPLICATIONS

Pork patties are an important meat product both in catering production for direct consumption and in convenience food industry when intended for refrigerated or frozen storage. As cooking is a main stage in preparation of patties for consumption, it is essential to use a method of cooking that ensures the high nutritional and sensory quality of products. Most often, pork patties are subjected to deep frying or traditional frying; however, several other cooking methods can be used. The present work shows that the combi oven cooking enables production of patties of desirable nutritional and sensory characteristics and low content of unfavorable compounds.     

THE INFLUENCE OF BIOPRESERVATIVES ON THE BACTERIAL LEVEL OF REFRIGERATED VACUUM PACKAGED BEEF1

Pediocin AcH (1,400 AU/g), nisin (1,400 AU/g), Nisaplin (500 IU/g). Microgard^TM (2%) or Na-lactate (2%) were added to refrigerated vacuum-packaged beef to determine their antibacterial properties. The influence of carbon monoxide treatment on meat color prior to biopreservative treatment was also studied. Pediocin AcH, Nisaplin and nisin had an immediate bactericidal effect on Leuconostoc inoculates. All biopreservatives kept bacterial populations in vacuum-packaged beef within log₁₀ 6/g for up to 8 weeks at 3C. Lactate was the most and Micrograd^TM the least effective in maintaining low bacterial concentrations during an 8 week storage period. The color of fresh beef treated with 10% CO + 90% N₂ for 60 min was stable for up to 4 weeks at 3C; however, beef treated with 100% CO retained its bright red color during 8 week of storage in the vacuum package.     

THE INFLUENCE OF AGING BEEF IN VACUUM

U.S. Choice grade beef loins and ribs were aged to determine the effect of vacuum packaging for 7 and 15 days at 32° and 40° F on sensory characteristics, microbial counts and weight loss. Vacuum packaging had no significant influence on tenderness, flavor and juiciness but produced a highly significant reduction in weight loss during aging. Surface bacterial counts were significantly less on the vacuum packaged portions than the portions not packaged.     

有色涤纶的细度对织物质量的影响

本文主要讨论了在毛精纺生产过程中，使用原液染色涤纶条与羊毛混纺时，原液涤纶条的细度对产品质量的影响。实践证明：只有采用细度分布适中的涤纶条，才能保证产品的最终质量。