Enhancing Phytochemical Compounds, Functional Properties, and Volatile Flavor Profiles of Pomelo (Citrus grandis (L.) Osbeck) Juices from Different Cultivars through Fermentation with Lacticaseibacillus paracasei

Abstract

The current study aimed to explore the effects of fermenting five different pomelo cultivars using Lacticaseibacillus paracasei on various physicochemical, phytochemical, and organoleptic attributes. Fermentation led to an increase in viable lactic acid bacteria count (8.80-9.28 log cfu/mL), organic acids, total polyphenols, and flavonoids, resulting in improved antioxidant activity, bile acid binding, cholesterol micellization disruption, and inhibition of pancreatic lipase activity. Additionally, some cultivars displayed higher levels of naringin, naringenin, and hesperetin after fermentation. The levels of volatile compounds were elevated after fermentation. The bitterness and overall acceptability scores were improved in the fermented samples of the Kao Numpueng cultivar. The principal component analysis (PCA) revealed that the Tubtim Siam cultivar demonstrated the highest functionality and health-related benefits among all fermented pomelos. Overall, the study suggests that pomelo exhibits potential as a valuable resource for creating a dairy-free probiotic drink enriched with bioactive phytochemical compounds and beneficial functional attributes.

Keywords: Lacticaseibacillus paracasei; flavonoids; lactic acid bacteria; pomelo juice; volatile compounds.

Figure 1

Effects of fermentation on bile acid binding (A,B), cholesterol micellization inhibition (C), and the pancreatic lipase inhibitory activity (D) of pomelo juices from different cultivars. Results are expressed as mean ± S.E.M. (n = 3). The means with different uppercase letters (fermentation effects) at the same cultivar are significantly different (p < 0.05). The means with different lowercase letters (treatment effects) are significantly different (p < 0.05). The abbreviations used for different cultivars are as follows: TS: Tubtim Siam; TD: Tong Dee; TK: Ta Koi; KN: Kao Numpueng; KY: Kao Yai; CHOL: Cholestyramine (3 mg/mL); Gallic acid at 0.5 mg/mL; Orlistat at 0.01 mg/mL; NF: Non-fermented juice; F: Fermented juice.

Figure 2

Acceptability scores of non-fermented and fermented pomelo juices from different cultivars (A–E). Data are presented as mean scores (n = 50). KY: Kao Yai (A); KN: Kao Numpueng (B); TS: Tubtim Siam(C); TD: Tong Dee (D); TK: Ta Koi (E); NF: Non-fermented; F: Fermented.

Figure 3

A biplot of the principal component analysis based on the phytochemical content, functional properties, and overall organoleptic acceptance scores of fermented and non-fermented pomelo juice cultivars. The data represent the average of three independent measurements. *Clusters were determined by Agglomerative Hierarchical Clustering. TS: Tubtim Siam; TD: Tong Dee; TK: Ta Koi; KN: Kao Numpueng; KY: Kao Yai; NF: Non-fermented; F: Fermented. TPC: Total Phenolic Content; TFC: Total Flavonoid Content; FRAP: ferric-reducing antioxidant power; DPPH: DPPH radical scavenging activity; TEAC: Trolox equivalent antioxidant capacity; MI: Cholesterol Micellization Inhibition; LI: Lipase activity inhibition; BEB: Bile Extract Binding; GDAB: Glycodeoxycholic acid Binding.