Effect of Thermal and Non-thermal Plasma Treatment on Particle Size Distribution, Protein Secondary Structure, Fuzzy Logic Sensory Evaluation, Rheological, and Selected Quality Attributes of Pineapple Juice: A Comparative Analysis

This study presents the comparative analysis of untreated, optimized non-thermal plasma (NTP)-treated (38 kV/631 s), extreme NTP-treated (45 kV/900 s), and thermally treated (95 celcius/12 min) pineapple juice (PJ) on enzyme activity, microbial count, protein structure, particle size, bioactive substances and, sensory, rheological, and biochemical attributes. The PJ treated with optimized NTP demonstrated merits over extreme NTP-treated and thermally treated in terms of the retention of bromelain, bioactive components, and biochemical attributes. Moreover, the fuzzy logic evaluation showed that optimized NTP-treated juice had superior sensory characteristics than extremely NTP- and thermally treated juice. The NTP approach, like thermal treatment (95 celcius/12 min), extends shelf life by assuring microbiological safety (<1 log10 cfu/mL) and enzyme inactivation (>90%). However, the thermal treatment resulted in loss of bioactive, sensory, and biochemical attributes. Particle size distribution indicates that NTP significantly (p < 0.05) reduced the sauter mean and volume mean diameter from 1617 to 894 nm and 1688 to 917 nm, respectively, which stabilized juice after treatment. NTP treatment substantially reduced the consistency from 1.22 to 0.31 mPa.sn and showed a pseudo-plastic behavior of juice. These results collectively imply that NTP has a tremendous ability to maintain bioactive compounds, and sensory and physicochemical attributes, as well as extend the shelf life of PJ.