ORIGINAL ARTICLE Microstructure of paneer prepared by automated pressing technique Chitranayak Sinha 1 | Manjunatha M. 2 | Jayaraj Rao K. 3 | Pushpanayak Sinha 4 | Khushbu Kumari 1 | Mahesh G. Kumar 5 | Jitender Kumar Dabas 1 1 Dairy Engineering Division, ICAR-NDRI, Karnal, India 2 Agriculture Engineering, UAS, ICAR, Bengaluru, India 3 Dairy Technology Division, SRS of ICAR- NDRI, Bengaluru, India 4 ICAR Research Complex For Eastern Region, Patna, India 5 Department of Dairy Engineering, Dairy Science College, ICAR, Hebbal, Bengaluru, India Correspondence Chitranayak Sinha, Dairy Engineering Division, ICAR-NDRI, Karnal 132001, India. Email: chitranayaksinha@gmail.com Abstract In this study, paneer was prepared by conventional method as well as by employing an automated pressing equipment and microstructure of paneer samples was studied by scanning electron microscopy. Further, pneumatic pressing of the hot coagulum was carried out at different pressures (2.5, 3.0, and 3.5 kg cm 2 ) and time durations (10, 12.5, and 15 min) using a semi-automated microprocessor based pneumatic pressing unit. It was found that the microstructure of paneer comprised mainly of continuous medium of casein matrix in which micro-pores were distributed. How- ever, differences were observed in the way the curd particles were fused during the pressing process of paneer manufacture. Paneer obtained from the automated press was found to possess more uniformity than the one prepared by conventional method. This was attributed to more uniform pressure applied by the automated technique. Further, porosity values were correlated with the openness observed in the microstructure of paneer. It was found that at an optimized pressure and time combination, paneer had a more uniform structure along with porosity than conven- tionally made one. The dependence of the paneer properties on the pressure and pressing time was well fitted to polynomial quadratic model which showed influence of pressure applied is greater than the time of pressing. Practical Applications The SEM imaging of paneer prepared by automated pneumatic pressing based tech- nique could be very useful in analyzing the microstructure which influences the tex- ture and amount of water retention. Small to medium scale paneer manufacturers could very well utilize the automated pneumatic pressing technique to produce pan- eer of optimum texture and adequate amount of moisture. Paneer manufacturers of small to medium scale could very well utilize this pressing technique to increase their income at farm level. 1 | INTRODUCTION Paneer, as a very popular heat-acid coagulated product of milk in India and in many other parts of the world, is a highly rich source of nutrition for good quality protein, fat, vitamins and minerals like cal- cium and phosphorus (Dey et al., 2020; Kumar, Mishra, Sutariya, Chaudhary, & Rao, 2019). It is used in various culinary dishes and snack items throughout the Indian subcontinent. The paneer, gener- ally having an appearance of white in color, has a sweetish-acidic nutty flavor, spongy kind of body and closely knit type of texture. It is extensively used for preparing variety of culinary dishes and snacks. Consumers give importance to body and texture of paneer as much as Received: 14 January 2021 Revised: 27 April 2021 Accepted: 6 June 2021 DOI: 10.1111/jfpe.13786 J Food Process Eng. 2021;e13786. wileyonlinelibrary.com/journal/jfpe © 2021 Wiley Periodicals LLC. 1 of 16 https://doi.org/10.1111/jfpe.13786