An overview of different homogenizers, their working mechanisms and impact on processing of fruits and vegetables.

Fruits and vegetables (F&V) are the second highest recommended foods, rich in antioxidants, vitamins and minerals, vital for building immunity against chronic diseases. F&V processing involves particle size reduction, for which different types of homogenizers, categorized as mechanical homogenizers, pressure homogenizers and ultrasonic homogenizers are used. The review discusses different types of homogenizers, their working mechanism, and application in F&V processing. Among mechanical homogenizers, knife mills are used for primary size reduction, ball mills for the micronization of dried F&V and rotor-stator homogenizers for emulsification. Use of the ultrasonic homogenizer is limited to extraction of bioactive compounds or as a pre-treatment for dehydration of F&V. High-pressure homogenizers are most widely used and reported due to the synergistic effect of homogenization and temperature increase, resulting in longer shelf-life and better physicochemical properties of the product. Additionally, the review also explains the effect of homogenization on the physicochemical, sensory and nutraceutical properties of the product.

Techno-Economic Analysis of the Multiple-Pass Ultrasonication with Mechanical Homogenization (MPUMH) Processing of Processed Carrot Discards to Puree.

A sustainable valorization process for puree processing from processed carrot discards (PDCs) was proposed by using multiple-pass ultrasonication with mechanical homogenization (MPUMH), optimized at 9 min ultrasonication followed by mechanical homogenization for 1 min, subjected to three passes. Techno-economic analysis of the puree processing plant was studied for two process models using SuperPro Designer for a plant with a capacity of 17.4 MT/day, operational for 26 weeks, with a 20-year lifetime. The two scenarios were (i) base case (PDCs processed without peels and crowns) and (ii) case 2 (PDCs and carrots (50:50, w/w) processed with peels and crowns). Both scenarios were economically feasible with an internal rate of return (IRR) and return on investment (ROI) at 24.71% and 31.04% (base case) and 86.11% and 119.87% (case 2), respectively. Case 2 had a higher total capital investment (Can$13.7 million) but a lower annual operating cost (Can$8.9 million), resulting in greater revenue generation (Can$29.7 million), thus offering a higher ROI. Sensitivity analysis related to the number of passes on puree quality and price is suggested to lower the capital investment. For the base case, a lower ROI was due to the high labor cost incurred for manual peeling of PDCs, indicating the critical need for developing a commercial peeler equipped to cut labor costs and increase profitability. The study casts insights into the techno-economic performance of a sustainable process for the valorization of PDCs.