**Subscripts**

*Biomimetics*

**3. Conclusion**

**Acknowledgements**

**Conflict of interest**

**Nomenclature**

HP heat pump

BAR bypass air ratio

ASHP air source heat pump GSHP ground source heat pump SAHP solar-assisted heat pump CSHP chemical source heat pump

MER moisture extraction rate ANN artificial neural network COP coefficient of performance Q heating capacity (kW)

m mass flow rate (kg/s) Cp specific heat (kJ/kg K)

W power (kW) T temperature (°C) h enthalpy (kJ/kg)

t, Δt time (h)

CX-(17)1003 is thankfully acknowledged.

The authors declare no conflict of interest.

SMER specific moisture evaporation rate

d absolute humidity (kg water vapor/kg dry air) rs evaporative latent heat of water (kJ/kg)

Considering the drying kinetics of food products, HP technology is the best option

for new demands of energy efficiency, product quality at a lower cost, and lower environmental impact. Many studies have discussed the HP system for food drying and concluded that HP drying systems are suitable for heat-sensitive products. The biomimetic systems are contributing as a key element in smart drying processes and becoming a very useful factor in the food drying industry. However, it has some limitations in its widespread applications in food drying industry. In the case of a bioinspired electric nose, its sensing ability is greatly affected by humidity, background noise, temperature, sensor poisoning, and sensor variations. This chapter reported the contribution of HP technology in food drying. The demands of high-quality food products and energy-efficient technologies for food processing are increasing day by day. The future work on biomimetic systems and HP technology would allow researchers to produce more automated food drying plants involving innovative intelligent approaches. It can be seen in this book chapter, research and development in HP drying have improved to hybrid type HP dryers. No doubt, the performance of these hybrid systems has increased but would increase installation and processing costs.

The financial support of the College of Engineering, Nanjing Agricultural University, under the Jiangsu Agricultural Science and Technology Innovation Fund

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