Radio frequency identification (RFID) is an alternative technology with a potential to replace traditional universal product code (UPC) barcodes. RFID enables identification of an object from a distance without requiring a line of sight. RFID tags can also incorporate additional data such as details of product and manufacturer and can transmit measured environmental factors such as temperature and relative humidity. This article presents key concepts and terminology related to RFID technology and its applications in the food industry. Components and working principles of an RFID system are described. Numerous applications of RFID technology in the food industry (supply chain management, temperature monitoring of foods, and ensuring food safety) are discussed. Challenges in implementation of RFID technology are also discussed in terms of read range, read accuracy, nonuniform standards, cost, recycling issues, privacy, and security concerns.

Shelf-stable milk could benefit from sensory quality improvement. Current methods of heating cause flavor and nutrient degradation through exposure to overheated thermal exchange surfaces. Rapid heating with microwaves followed by sudden cooling could reduce or eliminate this problem. The objectives for this study were focused on designing and implementing continuous microwave thermal processing of skim fluid milks (white and chocolate) to compare sensory, microbiological, and biochemical parameters with conventionally prepared, indirect UHT milks. All test products were aseptically packaged and stored at ambient temperature for 12 mo. Every 3 mo, samples were taken for microbiological testing, reactive sulfhydryl determinations, active enzyme analysis, instrumental viscosity readings, color measurements, and descriptive sensory evaluation. Microbiological plate counts were negative on all milks at each time point. Enzymatic assays showed that plasmin was inactivated by both heat treatments. 5,5'-dithio-bis(2-nitrobenzoic acid) analysis, a measure of reactive sulfhydryl (-SH-) groups, showed that the initial thiol content was not significantly different between the microwave-processed and UHT-treated milks. However, both heating methods resulted in an increased thiol level compared with conventionally pasteurized milk samples due to the higher temperatures attained. Sulfhydryl oxidase, a milk enzyme that catalyzes disulfide bond formation using a variety of protein substrates, retained activity following microwave processing, and decreased during storage. Viscosity values were essentially equivalent in microwave- and UHT-heated white skim milks. Sensory analyses established that UHT-treated milks were visibly darker, and exhibited higher caramelized and stale/fatty flavors with increased astringency compared with the microwave samples. Sweet aromatic flavor and sweet taste decreased during storage in both UHT and microwave milk products, whereas stale/fatty flavors increased over time. Sensory effects were more apparent in white milks than in chocolate varieties. These studies suggest that microwave technology may provide a useful alternative processing method for delivery of aseptic milk products that retain a long shelf life.

Milk with different fat contents (0, 1, 2, 4%, and chocolate milk) were heated in a specially designed continuous-flow microwave applicator operating at 915 MHz. The nominal power was 5 kW and the flow rates were 2.0 and 3.0 L/min to attain laminar flow. Temperature profiles at the exit of the applicator were measured. The results showed that the average increases in temperature were similar to one another, being 42°C at 2.0 L/ min and 29°C at 3.0 L/min. Differences between the lowest and highest temperatures were 3.7 and 3.0°C, respectively. The temperature profiles illustrated that slightly higher temperatures were achieved within segments flowing close to the center of the tube.

and viscosity did not change significantly compared with the untreated *) and viscosity did not change significantly compared with the untreated *) and viscosity did not change significantly compared with the untreated *) and viscosity did not change significantly compared with the untreated control. Pilot-scale tests were then conducted in a 60-kW microwave unit where the product was heated to 135 °C control. Pilot-scale tests were then conducted in a 60-kW microwave unit where the product was heated to 135 °C control. Pilot-scale tests were then conducted in a 60-kW microwave unit where the product was heated to 135 °C control. Pilot-scale tests were then conducted in a 60-kW microwave unit where the product was heated to 135 °C control. Pilot-scale tests were then conducted in a 60-kW microwave unit where the product was heated to 135 °C and held at that temperature for 30 s. The pilot-scale test produced a shelf-stable product with no detectable and held at that temperature for 30 s. The pilot-scale test produced a shelf-stable product with no detectable and held at that temperature for 30 s. The pilot-scale test produced a shelf-stable product with no detectable and held at that temperature for 30 s. The pilot-scale test produced a shelf-stable product with no detectable and held at that temperature for 30 s. The pilot-scale test produced a shelf-stable product with no detectable microbial count during a 90-d storage period at room temperature. This is the 1st report of aseptically packaged microbial count during a 90-d storage period at room temperature. This is the 1st report of aseptically packaged microbial count during a 90-d storage period at room temperature. This is the 1st report of aseptically packaged microbial count during a 90-d storage period at room temperature. This is the 1st report of aseptically packaged microbial count during a 90-d storage period at room temperature. This is the 1st report of aseptically packaged vegetable puree processed by a continuous flow microwave heating system. vegetable puree processed by a continuous flow microwave heating system. vegetable puree processed by a continuous flow microwave heating system. vegetable puree processed by a continuous flow microwave heating system. vegetable puree processed by a continuous flow microwave heating system.

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