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101.
Meat freshness has been monitored by various microbiological, chemical and sensorial indices. However, these methods are slow and not suited to automation. Infrared spectroscopy is one of the most convenient analytical tools which could be used to monitor the evolution of food quality. The aim of this work was to investigate the ability of both NIR (Near Infrared) and MIR (Mid Infrared) spectroscopy to follow meat freshness decay. The minced beef was packaged in high-oxygen modified atmosphere (30% CO2 and 70% O2) and stored at three temperatures. Spectra were collected by Fourier-Transformation (FT)-NIR and FT-IR instruments. PCA, applied to the data, was able to discriminate samples on the basis of storage time and temperature. The modelling of PC scores versus time allowed the setting of the time of initial freshness decay for the samples (6–7 days at 4.3 °C, 2–3 days at 8.1 °C and less than 1 day at 15.5 °C). 相似文献
102.
González-Rios H Peña-Ramos A Valenzuela M Zamorano-García L Cumplido-Barbeitia G González-Méndez NF Huerta-Leidenz N 《Journal of food science》2010,75(9):C747-C752
To compare beef from Northwestern Mexico (NMEX) and that imported from the United States in physical-chemical (PC) and sensory traits, samples of ribeye (m. Longissimus dorsi thoracis, LDT) and knuckle (m. Vastus lateralis, VL) of Mexican (64 LDT; 51 VL) and U.S. (28 LDT; 25 VL) origin were purchased randomly from select retail stores located in 3 cities of NMEX. PC evaluation measured contents of moisture, fat and cholesterol, Warner-Bratzler shear force (WBSF), pH, CIE L*, a*, and b*, cooking loss, and normalized fatty acid profile (FAP). Trained panelists evaluated raw and cooked samples for 2 and 6 different organoleptic traits, respectively. Mexican and U.S.-imported LDT steaks did not differ (P>0.05) in PC traits. VL samples differed in L*, b*, hue*, WBSF, and fat content by country of origin (COO). The WBSF for cooked VL samples from the United States was lower (P < 0.05) and fat content was greater (P<0.05) than those for NMEX steaks. The FAP varied between muscles; Mexican LDT had a higher content of C18:0, while VL from the United States had a higher proportion of polyunsaturated fatty acids (PUFA) and a higher PUFA/Saturated ratio (P<0.05). Although sensory traits tended to be rated higher for Mexican LDT and VL steaks, no statistical differences with U.S.-imported samples were detected (P > 0.05). Results indicated that domestic and U.S. retail steaks sold in the NMEX are similar in eating quality and PC, whereas differences observed in FAP deserve further attention from a nutritional standpoint. 相似文献
103.
Y.N. Kim D.W. Giraud M.A. Masrizal F.L. Hamouz K. Watanabe M.I. Schnepf A.S. De Mello Jr G.E. Erickson C.R. Calkins J.A. Driskell 《Journal of food science》2010,75(2):C166-C172
ABSTRACT: Vitamin E, thiamin, riboflavin, niacin, vitamin B6, and vitamin B12 concentrations of flat iron steaks and petite tenders from steers fed finishing rations containing 0% and 40% corn wet distiller's grains and solubles (WDGS) with and without supplemental vitamin E were determined. Feeding treatment groups were: 0% WDGS with basal vitamin E, 0% WDGS with supplemental vitamin E (500 IU daily), 40% WDGS with basal vitamin E, and 40% WDGS and supplemental vitamin E. Cattle can be fed 40% WDGS diets more economically than corn diets. The incorporation of 40% WDGS, with and without vitamin E, was hypothesized to have little effect on the vitamin concentrations of these value meat cuts. Flat iron steaks and petite tenders were broiled and/or grilled to 70 °C internal temperature. Mean cooking yields ranged from 68.7% to 78.2%. The majority of the vitamin concentrations of broiled and of grilled meat were significantly different (P < 0.05) from that of raw meat. Vitamin E concentrations of raw and cooked meat from steers that received supplemental vitamin E were significantly higher (P < 0.05) than those fed basal vitamin E. Significant differences in thiamin, riboflavin, vitamin B6, and vitamin B12 concentrations in raw flat iron steaks and in vitamin B6 in raw petite tenders were observed by WDGS. Thiamin, vitamin B6, and vitamin B12 concentrations of broiled flat iron steaks were significantly different (P < 0.05) than grilled. A few differences in vitamin concentrations of the flat iron steaks and petite tenders were observed by WDGS, vitamin E supplementation, and cooking treatments, but most of the vitamin concentrations were statistically similar. 相似文献
104.
ABSTRACT: We assessed the heat resistance of Salmonella in raw ground beef in both the absence and presence of sodium lactate, oregano oil, and in combinations of these 2 GRAS-listed ingredients, and determined their bactericidal or bacteriostatic activities during postthermal treatment storage at 15 °C. A cocktail of 8 serotypes of Salmonella spp. was inoculated into ground beef supplemented with sodium lactate (NaL) (1.5% and 3%) and/or oregano oil (0.5% and 1%) to obtain approximately 8 log CFU/g. The ground beef samples (3 g) were vacuum-packed and heated at 60, 65, or 71 °C in a circulating water bath for selected times to inactivate approximately 5 to 6 log CFU/g of the pathogen, and then stored at 15 °C for 15 and 30 d. Results show that especially at the lower cooking temperatures, addition of oregano oil increased the inactivation rate of Salmonella spp., whereas addition of NaL alone exhibited a protective effect against lethality and decreased the rate. Addition of combinations of oregano oil and NaL overcame this protective effect. During subsequent posttreatment storage for 15 d, Salmonella populations in the controls and in samples containing 0.5% oregano (60 and 65 °C) or 1% oregano oil (60 °C) increased to 4.5 to 6 log CFU/g. The values for all other samples were at or near undetectable levels. Results from the 30-d storage study were similar. These findings indicate that lactate and oregano oil may be used to render Salmonella spp. more susceptible to the lethal effect of heat and to inhibit growth of Salmonella spp. that survive heat treatments. 相似文献
105.
ABSTRACT: Ground high (HCS), intermediate (ICS), and low color stability (LCS) cow muscles were used to investigate effects of blending muscles of different color stabilities on ground beef display color. Six formulations at 90% and 80% lean points combining HCS, ICS, and LCS muscles were: 50% HCS + 50% ICS; 50% HCS + 50% LCS; 50% ICS + 50% LCS; 33.3% HCS + 33.3% ICS + 33.3% LCS; 75% HCS + 25% LCS; and 25% HCS + 75% LCS. Patties were packaged in a high oxygen (80% O2 , 20% CO2 ) modified atmosphere, held in dark storage for 5 d, then displayed for 4 d. The 80% lean patties containing ≥ 50% HCS had the brightest red initial visual color. During display 75% HCS + 25% LCS at both lean points had the most cherry-red display color. Patties containing a greater proportion of HCS had greater metmyoglobin reducing ability throughout display. HCS, ICS, and LCS muscle can be mixed without adverse color affects, provided LCS muscle is ≤ 25%, and HCS muscle is ≥ 50% of the blend. 相似文献
106.
Beef patties formulated to contain beef fat, plant oil, and a rosemary extract to increase unsaturated fatty acid content and maintain desirable sensory attributes were compared to control beef patties formulated without plant oils. Treatment patties were formulated to a fat content of 10% or 20% by combining beef trimmings (6% fat) with 4% or 14% addition of a lipid blend. Blends contained 57% beef tallow, 0.3% rosemary extract, and 43% of high oleic safflower oil (SO), olive oil (OO), or corn oil (CO). Lipid oxidation, as measured by TBA values, of treatment patties were similar to control patties after 0 and 3 d of refrigerated (2 °C) storage and up to 56 d of frozen (-10 °C) storage. Cooked lipid blend patties having a fat content of 10% or 20% were similar to or higher than control patties for juiciness and were no different for other sensory attributes evaluated. At fat levels of 10% or 20%, oleic acid (18: 1) in cooked SO patties (46.1% and 50.3%, respectively) and OO patties (43.8% and 48.1%, respectively) was higher than the control (37.3% and 37.6%, respectively). Unsaturated to saturated fatty acid ratios at the 10% or 20% fat levels were higher in SO (1.37 and 1.60, respectively) and CO (1.40 and 1.48, respectively) patties than the control (0.97 and 0.94, respectively). Beef patties manufactured with varying lipid blends increased unsaturated fatty acid content and were similar in physical characteristics and sensory attributes of all beef patties formulated without lipid blends. PRACTICAL APPLICATION: The development of healthier beef products that will be more appealing to consumers has long been an industry goal. The authors believe that lipid blends such as the one used in this study could be used to create such products, not only in the form of beef patties, but any number of processed meat products. Because the materials and equipment used to create the lipid blends in this study are widely available, their incorporation into meat products would represent a small capital investment. This is an important factor in bringing a reasonably priced, healthier product to consumers. 相似文献
107.
Michele Espinosa da Cunha Laiza Canielas Krause Maria Silvana Aranda Moraes Candice Schmitt Faccini Rosângela Assis Jacques Suelen Rodrigues Almeida Maria Regina Alves Rodrigues Elina Bastos Caramão 《Fuel Processing Technology》2009
In the present work, the process of biodiesel production in a pilot plant has been studied using beef tallow as raw materials with methanol and potassium hydroxide as catalyst. The biodiesel quality is regulated by Brazilian specifications (Resolution 42) by the National Agency of Petroleum (ANP). The alkaline transesterification of animal fat with methanol produces a biodiesel with high quality and also with a good conversion rate. The process is possible but the economical viability must be improved by recovering methanol and glycerin. The obtained results have been used for industrial scale up of the process. 相似文献
108.
以干酪乳杆菌和肉糖葡萄球菌为发酵剂生产牛肉发酵香肠,并对该工艺进行了研究.结果表明,最佳工艺为:接种量为1.5·107,葡萄糖酸-δ-内酯(GDL)的添加量为0.6%,葡萄糖(GLC)的添加量为0.25%. 相似文献
109.
110.
茶多酚与维生素C联合抑制牛肉干沙门氏菌研究 总被引:2,自引:0,他引:2
将鼠伤寒沙门氏菌添加于模拟牛肉干肉汤中,将茶多酚与Vc以不同比例混合,测试二者对沙门氏菌抑制效果是否有协同效应。结果表明,一定比例混合的茶多酚与Vc对抑制沙门氏菌具有增效作用,当混合物中茶多酚为1.0mg/mL、Vc为0.1mg/mL时,协同抑制率最高,达98.06%。 相似文献