Improvement of Bangka’s white pepper quality using gamma irradiation technology: microbial contamination reduction

Abstract

The improvement of Bangka’s white pepper quality in term of microbial contamination and physicochemical parameters has been done using gamma irradiation. Pepper samples were irradiated using gamma rays with dose of 2 to 10 kGy, and 0 kGy as unirradiated (control). The Harwell dosimeter was used to determine the absorbed dose. To evaluate the storage effect on the Bangka’s white pepper quality, the optimum irradiation dose of 8 kGy was used and peppers were then kept at room temperature (27°C) for 3, 6, 9 and 12 months. The results showed that unirradiated sample was contaminated by bacteria and mold, both of them with concentration of 103 up to 104, while there was no contamination of yeast, E. coli and Salmonella. The physicochemical properties such as light berries, dark-colored berries, moisture, piperine and essential oil contents were 1.7, 0.7, 11, 5.5 and 2.8 (w/w), respectively. Gamma irradiation with dose of 2, 4, 6, 8 and 10 kGy reduced the number of bacteria to 3.5x101, 2.5x101, less than 10, less than 10 and 1.5x101 cfu/g, respectively. While for mold, irradiation from 2 up to 10 kGy reduce the number of molds to become less than 10 cfu/g. From the dose evaluation, irradiation dose of 8 kGy was selected to evaluate the effect of storage time. It was found that storage time up to 12 months, unirradiated sample still showed contamination of bacteria from 103 up to 104 cfu/g, while the irradiated pepper showed the contamination less than 10 cfu/g. The effect of storage time on physicochemical properties showed that there is no significant change for both unirradiated and irradiated pepper even after kept for 12 months. Piperine and essential oil contents of unirradiated pepper were 5.45 and 2.4%, respectively. Irradiated pepper showed slightly higher piperine content compared to un-irradiated. It can be concluded that gamma irradiation with a dose of 8 kGy is effective to improve the quality of Bangka’s white pepper while maintaining its bioactive substances (piperine and essential oil) and other physicochemical properties as well.

Quality Improvement of White Pepper with Processing through Optimizing the Ratio of Starter Culture from Acetobacter sp., Bacillus subtilis, and Bacillus cereus

“…White pepper has to be free from pathogenic and non-pathogenic contamination i.e., bacteria, mold and In addition, contaminated pepper can also serve as disease transmission vehicles and cause death if contaminated with harmful microorganisms, microbial toxins or environmental contaminants (Darwis et al 2020). According to Kaur and Gautam (2019), food is considered to be spoiled when the appearance, texture, flavor and odor are changed because microbes could have entered the food.…”

“…Furthermore, Indonesia was the third highest white pep-per producer supplying 18,000 tons of white pepper after China and Vietnam (Nedspice 2015). Traditionally, white pepper in Indonesia produced by soaking the fully ripened pepper berries in water for about 2-3 weeks to decorticate the pericarp (Darwis et al 2020). Several factors like safety, hygiene and quality (bulk density, moisture content, light berries, and microbial contamination) of white pepper are often neglected during the water retting process.…”