Using microwave metrology to count calories

Microwave sensor technologies for food evaluation and analysis: Methods, challenges and solutions

“…The degradationof food finally reflects in a variation of permittivity, which provides the possibility to determine the quality with an electromagnetic measurement systems (Venkatesh and Raghavan 2004).The sensor systems are used to obtain electrical data that characterises materials as propagation medium, and these electrical data can be used to calculate the moisture content (Knöchel et al 2001), contamination (Shaji and Akhtar 2013), freshness (Pacquit et al 2006), calories (Lexa et al 2015), and composition of a material (Kent et al 2001).There aremany valuablefindings thatare regarded as building blocks ofmicrowave sensors for food quality evaluation, and they have already demonstrated the feasibility. A number of investigations on measuring food of different categories with microwave sensor technologies have been reported in the recent years, such as corn (Seifi and Alimardani 2010), mashed potato (Guan et al 2004), meat (Clerjon and Damez 2009), chicken (Zhuang et al 2007), beef (Ng et al 2009), fish (Kent et al 2007),prawn, poultry meat and scallops (Kent and Anderson 1996), butter (Shiinokiet al 1998), yoghurt(Bohigaset al 2008, milk (Agranovich et al 2015), fruit juice (Lee et al 2010), vegetable oil (Korostynska et al 2013),cereal grain and seed (Trabelsi and Nelson 2003), etc.General principles, technologies, and somemicrowave sensor based food measurement applicationshave been discussed in several review articles (Nelson 2006;Gibson et al 2008;Jha et al 2011;Chandrasekaranet al2013).…”

“…The degradation of food finally reflects in a variation of permittivity, which provides the possibility to determine the quality with an electromagnetic measurement systems (Venkatesh and Raghavan, 2004). The sensor systems are used to obtain electrical data that characterises materials as propagation medium, and these electrical data can be used to calculate the moisture content (Knöchel et al, 2001), contamination (Shaji and Akhtar, 2013), freshness (Pacquit et al, 2006), calories (Lexa et al, 2015) and composition of a material (Kent et al, 2001). There are many valuable findings that are regarded as building blocks of microwave sensors for food quality evaluation, and they have already demonstrated the feasibility.…”

“…Dielectric spectroscopy is also used for analysis of food characteristics and parameters, such as quality defects, calories, density, storage, and so forth. Applications include the determination of quality defects in porcine muscle (Castro-Giráldez et al, 2010c), calories of homogeneous mixtures of oil, sugar and water (Lexa et al, 2015), bulk density and moisture content of cereal grain and oilseed (Trabelsi and Nelson, 2003), moisture content of wheat (Bartley et al, 1998), and the dielectric properties of hard red winter wheat (Nelson and Stetson, 1976). In these studies, dielectric spectroscopy is used to obtain the characteristics and parameters of foodstuffs with data analysis.…”