The maple syrup industry generates substandard syrups and sugar sand as by-products, which are underused. In this study, we conducted a comprehensive analysis of the physicochemical composition of these products to assess their potential for valorization. Using HPLC analysis, we measured sugar and organic acid content as well as total polyphenol content using the Folin-Ciocalteu method. Additionally, we evaluated the in vitro digestibility using the TIM-1 model. We showed that the composition of ropy and buddy downgraded syrups is comparable to that of standard maple syrup, whereas sugar sand\'s composition is highly variable, with carbohydrate content ranging from 5.01 mg/g to 652.89 mg/g and polyphenol content ranging from 11.30 µg/g to 120.95 µg/g. In vitro bioaccessibility reached 70% of total sugars for all by-products. Organic acid bioaccessibility from sugar sand and syrup reached 76% and 109% relative to standard maple syrup, respectively. Polyphenol bioaccessibility exceeded 100% during digestion. This can be attributed to favorable extraction conditions, the breakdown of complex polyphenol forms and the food matrix. In conclusion, our study demonstrates that sugar sand and downgraded maple syrups exhibit digestibility comparable to that of standard maple syrup. Consequently, they hold potential as a source of polyphenols, sugar or organic acids for applications such as industrial fermentation or livestock feeds.

Exopolysaccharide (EPS)-producing bifidobacteria, particularly Bifidobacterium animalis subsp. lactis strains, are used in the functional food industry as promising probiotics with purported beneficial effects. We used three isogenic strains of B. animalis subsp. lactis, with different EPS producing phenotypes (mucoid-ropy and non-ropy), in order to determine their capability to survive the murine gastrointestinal tract transit, as well as to evaluate their role in improving clinical outcomes in a chemically-induced colitis model. The three strains were able to survive in the intestinal tract of C57BL/6J mice during the course of the intervention study. Furthermore, the disease activity index (DAI) of the animal group treated with the ropy strain was significantly lower than of the DAI of the placebo group at the end of the treatment. However, no significant differences were found among the three strains. The analysis of several immune parameters, such as TNFα and IL-10 quantified in blood plasma and lymphocyte populations enumerated in mesenteric nodes, showed some significant variations among the four experimental animal groups. Remarkably, a higher capability of the ropy strain to increase regulatory T-cells in mesenteric lymphoid nodes was demonstrated, suggesting a higher ability of this strain to regulate inflammatory responses at mucosal level. Our data indicate that strains of B. animalis subsp. lactis producing EPS that confer a mucoid-ropy phenotype could represent promising candidates to perform further studies targeting intestinal inflammatory processes.

OBJECTIVE: To characterize Lactobacillus strains with EPS-producing ability compared with non-EPS-producing lactobacilli of the same species for technological performance including simulated gastrointestinal tract (GIT) conditions.
RESULTS: Characterization of EPS-producing Lactobacillus mucosae DPC 6426 in detail based on 16S rRNA sequencing, and EPS production using scanning electron and atomic force microscopy. The EPS was found to consist of mannosyl residues, with mannose, glucose and galactose found to be the major sugar residues present in an approximate ratio of 3: 2: 2. The strain was compared to non-EPS-producing Lact. mucosae DPC 6420 following exposure to salt, bile, acid and heat stresses. Lact. mucosae DPC 6426 exhibited twofold increased (P < 0·05) survival during 120-min exposure to 5 mol NaCl, threefold increased survival during 90-min exposure to 0·7% (w/v) bile (P < 0·05), threefold increased survival when exposed to simulated gastric juice (P < 0·001) for 10 min and fivefold increased survival during 60-min exposure to HCl (P < 0·01) compared with Lact. mucosae DPC 6420. Furthermore, Lact. mucosae DPC 6426 was found to be more heat tolerant (P < 0·001) compared with Lact. mucosae DPC 6420 during 30-min exposure to 55°C.
CONCLUSIONS: These data indicate that the EPS-producing Lact. mucosae DPC 6426 exhibits technological and biological robustness compared with a non-EPS-producing Lact. mucosae strain.
CONCLUSIONS: The data implicate the potential suitability of EPS-producing Lact. mucosae DPC 6426 in food applications and/or as a probiotic culture.