Effect of temperature and soluble solid onBacillus subtilisandBacillus licheniformisspore inactivation and quality degradation of pineapple juice

Abstract

Bacillus subtilis and Bacillus licheniformis spores can survive processing temperatures used in the thermal processes of high-acid foods. Therefore, this study investigated the thermal inactivation of B. subtilis and B. licheniformis spores in pineapple juice at different temperatures (85–100°C) and soluble solids (SS, 11–30°Brix). The quality of juices and microbial loads after the thermal treatments during storage at 4 °C for 35 days was then checked. A linear decrease in D-value was observed with increasing temperature of treatment. Furthermore, the D-values determined in pineapple juice were: D90°C=13.2 ± 0.5 mins, D95°C = 6.8 ± 0.9 mins and D100°C = 2.1 ± 1.7 mins for B. subtilis spores, and D85°C = 16.6 ± 0.4 mins, D90°C = 7.6 ± 0.5 mins and D95°C = 3.6 ± 1.5 min, for B. licheniformis. Generally, the susceptibility of the bacteria to soluble solid change was affected by the interaction between temperature, SS and strain. In addition, pasteurization processes of ≥95°C for ≥33.8 mins was needed to ensure a recommended 5-log reduction of B. subtilis spores and limit vitamin C degradation of pineapple juice within three-week of storage at 4 °C.

Nonthermal pasteurization of pineapple juice: A review on the potential of achieving microbial safety and enzymatic stability

“…Evelyn et al. (2021) used PEF (11.3 pulses at 65 kV/cm) for the inactivation of Eupenicillium Javanicum ascospores in the pineapple juice with varying total soluble solids (TSS of 10–30 °Brix). They obtained 4.0, 3.1, and 1.3 log cycle reductions in the ascospore population with TSS levels of 10, 20, and 30 °Brix, respectively.…”

“…In the last decade, pasteurization of pineapple juice was explored using various nonthermal treatments. These include PEF (Abu et al, 2020;Dastgheib et al, 2014;Evelyn et al, 2021;Indriani et al, 2019), ultrasound (US) treatment (Bevilacqua et al, 2014;Paniagua-Martínez et al, 2018;Yeoh & Ali, 2017), pulsed light (PL) (Preetha et al, 2016(Preetha et al, , 2021Vollmer, Chakraborty, et al, 2020), high-pressure processing (HPP) (Wu et al, 2021), and pressure change technology (PCT) (Vollmer et al, 2021;Vollmer, Santarelli, et al, 2020). To add more, some of the researchers also explored kinetic modeling of degradation of bioactive compounds.…”

Analysis of spore-forming bacterial contaminants in herbs and spices and evaluation of their heat resistance

“…The extrapolated D 121 values were 0.57, 0.76, 0.71, and 1.45 min, respectively. Evelyn et al (2021) determined that the D-values for B. subtilis in 11 °Brix pineapple juice were 2.1 ± 1.7 min at 100 °C, 6.8 ± 0.9 min at 95 °C, and 13.2 ± 0.5 min at 90 °C (p < 0.05). Moreover, Rodriguez et al (1993) reported the D-values for B. subtilis 075-T-0 in tomato juice were 5.7 min at 100 °C and 15.8 min at 95 °C.…”

Application of fruit juice for proliferation of Bacillus to control fungal phytopathogens

“…Juice of many fruits are probably the natural habitat of Bacillus spp. as reported by Alwakeel and Al-Humaidi (2008), Aneja et al (2014), andEvelyn et al (2022). This study was carried out to apply a juice-based medium for the proliferation of Bacillus strain(s) that antagonize Phytophthora capsici, Rhizoctonia solani, and Sclerotium rolfsii.…”