Optical scattering in beef steak to predict tenderness using hyperspectral imaging in the VIS-NIR region

The objective of this research is to develop a non-destructive method for predicting cooked beef tenderness using optical scattering of light on fresh beef muscle tissue. A hyperspectral imaging system (λ = 496–1,036 nm) that consists of a CCD camera and an imaging spectrograph, was used to acquire beef steak images. The hyperspectral image consisted of 120 bands with spectral intervals of 4.54 nm. Sixty-one fresh beef steaks, including 44 strip loin and 17 tenderloin cuts, were collected. After imaging, the steaks were cooked and Warner-Bratzler shear (WBS) force values were collected as tenderness references. The optical scattering profiles were derived from the hyperspectral images and fitted to the modified Lorentzian function. Parameters, such as the peak height, full scattering width at half maximum (FWHM), and the slope around the FWHM were determined at each wavelength. Stepwise regression was used to identify 7 key wavelengths and parameters. The parameters were then used to predict the WBS scores. The model was able to predict WBS scores with an R = 0.67. Optical scattering implemented with hyperspectral imaging shows limited success for predicting current status of tenderness in beef steak.     

A novel technique for the preparation of secondary fatty amides

A technique for the synthesis of monosubstituted fatty amides at low temperature and ambient pressure was developed. This method involved the condensation of an amine with a triacylglycerol. The primary amine (ethyl,n-butyl,n-hexyl andn-octyl were tested) acted as reagent and solvent for the fatty substrates. No additional organic solvent or catalyst was added. Tallow, vegetable oils and fish oil all served well as substrates, as did pure tripalmitin. The rate of amidation was dependent upon temperature and the ratio of fat to amine. In a series of experiments conducted with tallow andn-butylamine at a fat:amine molar ratio of 1:16, amidation could be carried out at 20°C, producingn-butyltallowamide in 83% yield in 24 hr. When the fat:amine molar ratio was reduced to 1:8, and the temperature raised to 45°C, the amide yield was 87.6% in 24 hr. When the reaction was carried out at the boiling point ofn-butylamine (78°C) and at a fat:amine ratio of 1:8, the amide yield was 93.2% in 4 hr. The reaction progressed more rapidly with higher molecular weight amines. The identity and purity of the amides was assessed by thin-layer chromatography and confirmed by elemental analyses and infrared and C¹³ nuclear magnetic resonance spectroscopy.     

Characteristics of Uruguayan mutton tallow

Fourteen samples of Uruguayan mutton tallow available in the local market were analyzed for their composition, melting point and titer. From the results it can be concluded that Uruguayan mutton tallow contains a higher percentage of oleic acid and a lower percentage of palmitic and stearic acids than that of other countries.     

基于RFID技术的肉牛养殖质量安全可追溯系统研究

消费者和国际贸易对食品质量的要求日益提高,而运用监控、预警、追踪、追溯等技术在食品生产的关键环节上进行的质量监控是有效保障食品质量安全的重要手段。研究采用B/S（浏览器/服务器）模式结构体系,基于RFID技术构建了肉牛养殖可追溯系统。系统通过应用RFID技术,实现了对每头肉牛的养殖信息的自动采集,并针对每头肉牛形成可在Internet网络上进行查询的质量追溯档案。解决了牛肉在肉牛养殖环节（牛肉生产源头）上进行以肉牛个体为单位实施质量监控和实现可追溯的问题。     

Environmental life-cycle inventory of detergent-grade surfactant sourcing and production

Life-cycle inventories were compiled to characterize natural resource requirements and environmental emissions associated with the sourcing and production of selected, detergent-grade surfactants and surfactant feedstocks. Petrochemical surfactant types examined were linear alkylbenzene sulfonate, alcohol sulfate (AS), alcohol ethoxylate (AE) and alcohol ethoxylate sulfate (AES). Oleochemical surfactants derived from palm oil, palm kernel oil and inedible tallow were AS, AE, AES and (for palm oil and tallow) methyl ester sulfonate. It was determined that natural resource requirements were primarily related to the source of feedstock and secondarily to surfactant type. Likewise, the composition and mass of atmospheric, aqueous and solid emissions were principally determined by feedstock source. Energy requirements varied as a function of both feedstock and surfactant type. The inventories do not support fundamental shifts in surfactant usage or feedstock sourcing on the basis of environmental concerns, as no single surfactant or feedstock was identified as superior across all resource and emissions criteria examined. The data provide baselines for evaluating opportunities for resource optimization, pollution prevention and waste minimization within each production technology surveyed.     

Three-dimensional measurement of ice crystals in frozen beef with a micro-slicer image processing system

A novel technique has been developed for measuring the three-dimensional (3-D) structure and distribution of ice crystals formed in frozen beef by using a micro-slicer image processing system (MSIPS). The system has functions to reconstruct the 3-D image based on the image data of exposed cross-sections obtained by multi-slicing of a frozen sample with the minimum thickness of 1 μm and to display the internal structure as well as an arbitrary cross-section of the sample choosing observation angles. The size and distribution of ice crystals can be determined from the 2-D quantitative information, such as the periphery and area of the crystals. The effects of freezing conditions on the morphology and distribution of the ice crystals were demonstrated quantitatively from the observations of raw beef stained by fluorescent indicator. For the samples frozen at −15 °C, the network structure of ice crystals were observed mainly at intercellular space, having approximately 100 μm in cross-sectional size, while that prepared at −120 °C showed the spherical crystals of 10–20 μm in diameter within the cells. The 3-D image of the sample demonstrated that the growth of ice columns was restricted by the intrinsic structure of muscle fibers. The proposed method provided a new tool to investigate the effects of freezing conditions on the size, morphology and distribution of ice crystals.     

Development of a controlling method for Escherichia coli O157:H7 and Salmonella spp. in fresh market beef by using polylysine and modified atmosphere packaging

Escherichia coli O157:H7 and Salmonella spp. often contaminate fresh beef. In Japan, an E coli outbreak caused by raw beef made 181 people ill and 5 individuals dead in 2011. Responding to this outbreak, an effective sterilization method for fresh beef is expected to be developed. In this study, ε-polylysine combined with CO₂-packaging method was examined for controlling these pathogens in fresh beef. At an incubation temperature of 4 °C, approximately 4.3 log and 2.4 log reduction in bacterial numbers were observed after 7-day incubation for E. coli O157:H7 and Salmonella, respectively, in ε-polylysine-added beef. When effectiveness of CO₂-packaging combined with ε-polylysine was investigated, CO₂ did not have additional inhibiting effect on bacterial growth compared to only-ε-polylysine-treated samples when incubated at 4 °C. However, effectiveness of CO₂ was observed when incubated at 10 °C where approximately 2.9 log and 4.4 log reduction in E. coli cell numbers were observed in only-ε-polylysine-treated samples and polylysine- and CO₂-treated group, respectively, and approximately 1.7 log and 3.5 log reduction in Salmonella cell numbers were observed in only-ε-polylysine-treated samples and polylysine and CO₂-treated group, respectively. This study confirmed that ε-polylysine or ε-polylysine combined with CO₂ packaging are effective in preventing foodborne diseases caused by raw beef.     

The relationship between numbers of bacteria on surfaces and in deep tissues of mechanically tenderized beef

The objective of the study was to identify factors affecting the fractions of the bacteria naturally present on surfaces of beef cuts that are carried into deep tissues when the meat is mechanical tenderized by piercing with banks of thin blades. The surfaces and ten strips of meat from the deep tissues of beef primal cuts tenderized first and last on each of five days at a retail store meat fabrication facility were sampled for enumeration of total aerobic counts. Each strip was excised from the whole thickness of a cut after surfaces were sterilized. The mean log numbers of total aerobes recovered from the surfaces of cuts tenderized first or last each day were 2.18 and 1.57 log cfu cm⁻², respectively. The mean log numbers recovered per strip from individual cuts tenderized first or last each day ranged from 0.30 to 1.45 and from 0.03 to 1.04 log cfu, respectively. These findings indicate that bacteria from the tenderizing equipment augmented the numbers of aerobes on the surfaces of cuts tenderized first each day, with some of the additional aerobes being carried into deep tissues. Subsequently, pieces of cuts stored in air at 2 °C were tenderized at a laboratory using commercial equipment. Each cut was divided into three pieces with one piece being not treated, one being sprayed with water and one being sprayed with 5% lactic acid. The mean log numbers of total aerobes recovered from the surfaces of not treated pieces of cut stored for 0, 2, 4, 6, 10 or 14 days were 0.6, 0.8, 2.6, 4.2, 8.5 and 8.9 log cfu cm⁻², respectively. No aerobes were recovered from the deep tissues of any of the pieces of cuts tenderized on day 0. Mean log numbers recovered from the deep tissues of not treated tenderized pieces of cuts stored for 2, 4, 6, 10 or 14 days were 0.3, 0.3, 2.2, 7.8 and 8.1 log cfu per strip, respectively. Spraying with 5% lactic acid reduced the mean log numbers of aerobes on pieces of cuts stored for 2, 4, or 6 days by 1, 2 or 2 log units, respectively, but did not reduce the numbers on pieces of cuts stored for 10 or 14 days. Mean log numbers recovered from the deep tissues of tenderized pieces of cuts sprayed with 5% lactic acid were not significantly different (P > 0.05) from the mean log numbers recovered from the corresponding, tenderized not treated pieces of cuts. These findings showed that the fraction of the total aerobes on cut surfaces that are carried into deep tissues during mechanical tenderizing can vary with the stage of growth of the spoilage flora; and that reduction of numbers of aerobes on the surface by treatment with lactic acid before tenderizing does not necessarily reduce the numbers carried into deep tissues during tenderizing.     

Intensive sheep and beef production from pasture — A New Zealand perspective of concerns,opportunities and challenges

This paper details current production trends for sheep and beef cattle production in New Zealand and gives some insight into the opportunities for improvement based on New Zealand research at Massey University. Further it outlines some of the challenges the industries face in the near future. The New Zealand climate favours pasture growth and this is the key to sheep and beef cattle production with over 95% of the diet being grazed pasture or crop. Exports are the focus of the industry with 95% of sheep meat and wool, and 80% of beef exported. There have been considerable gains in production over the last 20 years but there still remains a huge opportunity for further intensification through breeding sheep at an earlier age, increasing the weight of lambs weaned per ewe per year and improving beef production systems. These improvements need to occur within a framework of minimal environmental footprint and produce products that are in demand in the high end international markets.     

An overview of the nutritional value of beef and lamb meat from South America

The southern region of South America, a subtropical and temperate zone, is an important region for the production of beef and lamb meat, which is mainly produced in extensive pasture-based systems. Because of its content in highly valuable nutrients such as iron, zinc, selenium, fatty acids, and vitamins, meat is a unique and necessary food for the human diet in order to secure a long and healthy life, without nutritional deficiencies. Beef and lamb production systems based on temperate or tropical grasslands show interesting and, in some cases, a differential content in minerals, fatty acids and vitamins. This review deals with the distinctive aspects of the nutritional quality of beef and lamb meat produced in this region in terms of nutritional composition and the bioavailability of key nutrients related to its contribution for a healthy diet for all ages.