Development of a non-dairy probiotic fermented product based on almond milk and inulin

A new fermented almond milk that combined the properties of both almonds and probiotics was considered to cover the current versatile health-promoting foods' demand. Almond milk fermentation with probiotic Lactobacillus reuteri and Streptococcus thermophilus was studied by using a Central Composite design with response surface methodology, and different factors (glucose, fructose, inulin and starters) were optimised to assure high probiotic survivals in the final product. The optimal formulation was physicochemically characterised throughout cold storage (28 days) and both probiotic survivals to invitro digestion and proteolysis were quantified. Results showed that a high probiotic population (>10(7) cfu/mL) was obtained in the previously optimised almond milk throughout storage time, which correspond to the addition of 0.75g of glucose/100mL, 0.75g of fructose/100mL, 2g/100mL inulin and 6mL/100mL inoculum. Glucose was used as the main nutrient and the production of mannitol by L. reuteri was detected. The fermentation process increased the viscosity values, forming a weak gel structure, whose physical properties hardly changed. Probiotic bacteria notably survived (51%) to the invitro digestion, surely related to the inulin presence, which would add value to the developed product by enhancing the potential health benefits of its consumption.This research has been carried out thanks to a funded project by the Universitat Politecnica de Valencia (PAID-05-11-2740). This work was also supported by the Conselleria de Educacion of Valencia government, which granted the author N. Bernat (ACIF/2011).Bernat Pérez, N.; Cháfer Nácher, MT.; Chiralt Boix, MA.; González Martínez, MC. (2015). Development of a non-dairy probiotic fermented product based on almond milk and inulin. 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Hazelnut milk fermentation using probiotic Lactobacillus rhamnosus GG and inulin

Following the consumer demand of healthy vegetable products due to their interesting nutritional profiles and potential functionalities, the fermentation process of hazelnut milk with Lactobacillus rhamnosus GG and S.thermophilus was studied. The effect of different factors (glucose, inulin and inoculum contents) was analysed to ensure sufficient probiotic survivals in a minimum time. The shelf life of the optimised product was characterised in terms of its main physicochemical and quality parameters (probiotic survivals and sensory analysis). Results showed that the defined formulation allowed high probiotic survivals (approximate to 10(8)cfumL(-1)) throughout cold storage and >60% survived to the in vitro digestion process (approximate to 10(5)cfumL(-1)). Lactobacillus rhamnosus GG was no able to degrade inulin, which remained to exert health benefits in the host. The product was highly appreciated by the sensory panel during its shelf life despite the formation of a weak gel, which presented syneresis at the last storage time.This research has been carried out thanks to a funded project by the Universitat Politecnica de Valencia (PAID-05-11-2740). This study was also supported by the Conselleria de Educacion of Valencian government, which granted the author N. Bernat (ACIF/2011).Bernat Pérez, N.; Cháfer Nácher, MT.; Chiralt Boix, MA.; González Martínez, MC. (2014). Hazelnut milk fermentation using probiotic Lactobacillus rhamnosus GG and inulin. International Journal of Food Science and Technology. 49(12):2553-2562. https://doi.org/10.1111/ijfs.12585S255325624912Allgeyer, L. C., Miller, M. J., & Lee, S.-Y. (2010). Sensory and microbiological quality of yogurt drinks with prebiotics and probiotics. Journal of Dairy Science, 93(10), 4471-4479. doi:10.3168/jds.2009-2582Angelov, A., Gotcheva, V., Kuncheva, R., & Hristozova, T. (2006). 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(2010). Processing optimization of probiotic yogurt containing glucose oxidase using response surface methodology. Journal of Dairy Science, 93(11), 5059-5068. doi:10.3168/jds.2010-3336DE SOUZA OLIVEIRA, R. P., PEREGO, P., CONVERTI, A., & DE OLIVEIRA, M. N. (2009). The effect of inulin as a prebiotic on the production of probiotic fibre-enriched fermented milk. International Journal of Dairy Technology, 62(2), 195-203. doi:10.1111/j.1471-0307.2009.00471.xDel Campo, R., Bravo, D., Canton, R., Ruiz-Garbajosa, P., Garcia-Albiach, R., Montesi-Libois, A., … Baquero, F. (2005). Scarce Evidence of Yogurt Lactic Acid Bacteria in Human Feces after Daily Yogurt Consumption by Healthy Volunteers. Applied and Environmental Microbiology, 71(1), 547-549. doi:10.1128/aem.71.1.547-549.2005Donkor, O. N., Nilmini, S. L. I., Stolic, P., Vasiljevic, T., & Shah, N. P. (2007). Survival and activity of selected probiotic organisms in set-type yoghurt during cold storage. 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Optimisation of oat milk formulation to obtain fermented derivatives by using probiotic Lactobacillus reuteri microorganisms

Functional advantages of probiotics combined with interesting composition of oat were considered as an alternative to dairy products. In this study, fermentation of oat milk with Lactobacillus reuteri and Streptococcus thermophilus was analysed to develop a new probiotic product. Central composite design with response surface methodology was used to analyse the effect of different factors (glucose, fructose, inulin and starters) on the probiotic population in the product. Optimised formulation was characterised throughout storage time at 4 ℃ in terms of pH, acidity, β-glucan and oligosaccharides contents, colour and rheological behaviour. All formulations studied were adequate to produce fermented foods and minimum dose of each factor was considered as optimum. The selected formulation allowed starters survival above 107/cfu ml to be considered as a functional food and was maintained during the 28 days controlled. β-glucans remained in the final product with a positive effect on viscosity. Therefore, a new probiotic non-dairy milk was successfully developed in which high probiotic survivals were assured throughout the typical yoghurt-like shelf life