CSIWC RF sensor for micro‐fluidic non‐contact quality assessment of milk

Abstract

In this work, the design of the SIW-based RF sensor is presented to assess the targeted quality of milk. In the present scenario, mainly two parameters, namely, purity and fat level are considered to assess the milk quality. Customized in-lab preparation of milk adulterant using low-grade vegetable oil, detergent, water, and glucose is carried out to analyze the practical milk adulteration scenario. Moreover, commonly consumed pure cow and buffalo milk samples are also collected to record the corresponding reference RF properties. A systematic approach is followed to develop the complete database related to actual milk samples with known fat percentages. Then accordingly, the proposed RF sensing mechanism is employed to identify the possible deviation in milk quality. The proposed work mainly employs the SIW-based noncontact RF sensing mechanism where the perturbation formulation is used to perform a qualitative assessment. Mathematical processing of the relative shift in the obtained S-parameters, corresponding to the variation in dielectric property of test samples at specified RF frequency, is carried out. Even though the work's main aim is a qualitative assessment of milk quality, dielectric property estimation of considered test samples is also performed to visualize their quantitative RF attributes. A compact, low-cost, non-contact, real-time, and microfluidic CSIWC RF sensor with high-quality factor and improved accuracy and sensitivity is designed.

A symmetric bar chart-shape microwave sensor with high Q-factor for permittivity determination of fluidics

“…Since the sensors can detect the type of material by determining the dielectric constant of the material, therefore different types of substances can be measured, for example, the amount of brine [27], blood glucose [28][29][30], methanol [31,32], milk [33], moisture [34][35][36][37], oil in food [38], amount of salt and sugar in water [16], type of tissue [39], determining the amount of phosphate and nitrate [40], and most importantly determining the type of solid or liquid [11] material are among the tasks carried out by sensors. One of the most important features of sensors in today's industry is that they are non-contact [27,33] and non-invasive [2,15,24,30]. To achieve such factors, different techniques have been used to design them which includes parallel coupled [41], phase variation [42], rat race coupled [43], spiral bandgap [34], and near-field self-injection-locked [34].…”

“…According to the needs of the industry, the use of material detection sensors using permittivity is widely used in the food industry, for example, the cavity technique is a method of interest to researchers in the petroleum industry, therefore, the sensors used in this industry are usually made by the cavity method [15, 45] or the amount of impurities and fat in milk was determined using the substrate integrated waveguide (SIW) technique. In this method, a combination of circular SIW with cavity was used and cow and buffalo milk were used as samples [33]. In [46] two SIW re-entrant cavity resonators integrate longitudinally for determination of relative dielectric liquid samples for high Q -factor.…”

Permittivity measurement of fluidics with high‐sensitivity by chandelier form microwave sensor

“…The MRS can detect the substance type according to the permittivity amount. The examples identified by the permittivity determination method include blood glucose, [21][22][23] moisture, [24][25][26][27] milk, 28 oil in food, 29 solution of sugar and salt, 30 amount of nitrate and phosphate. 31 The cavity technique is a method for researchers in the petroleum industry, therefore, the used MRSs in the industry can be fabricated by cavity model [32][33][34] or the amount of fat and impurities in types of milk was detected by the substrate-integrated waveguide structure.…”

“…The MRS can detect the substance type according to the permittivity amount. The examples identified by the permittivity determination method include blood glucose, 21–23 moisture, 24–27 milk, 28 oil in food, 29 solution of sugar and salt, 30 amount of nitrate and phosphate 31 …”