Antioxidant properties of probiotic fermented milk supplemented with chestnut flour (Castanea sativa Mill)

Abstract

The effect of sweet chestnut (Castanea sativa Mill) flour in stimulating the growth of probiotic bacteria in fermented skim milk produced with different probiotic strains, namely Lactobacillus acidophilus, L. rhamnosus and Bifidobacterium animalis subsp. lactis was evaluated. Microbial counts, pH, total titratable acidity (LA %) and syneresis were measured in fermented skim milk samples. Additionally, the antioxidant capacities of the samples were measured by Trolox equivalent antioxidant capacity (TEAC), free radical scavenging activity (DPPH), and Ferric Reducing‐antioxidant Power (FRAP) assays. The viability and growth proportion index (GPI) of L. rhamnosus were significantly higher than those of L. acidophilus and B. lactis in all samples during storage. Results indicated that all probiotic fermented milks enriched with chestnut flour displayed significant probiotic viability (>7 log10 cfu/g) with high antioxidant capacities. L. acidophilus, L. rhamnosus and B. lactis survived throughout the shelf life of the chestnut‐fermented skim milk, and remain at this satisfactory viability level even after 21 days of storage. The antioxidant capacity and phenolic contents were dependent on probiotic strains used. Practical applications Nowadays the focus is rather on the effects of foods on maintenance of health, well‐being and prevention of certain diseases than simply satisfaction of appetite or nutrition. The consumers’ health consciousness due to the scientific knowledge of the interactions between diet and health is a driving factor to develop products with health‐related claims such as probiotic foods. This paper investigated the effects of chestnut flour supplementation not only on viability of probiotic bacteria but also the antioxidant capacity and phenolic contents in fermented milk throughout predicted shelf life. The results indicated that chestnut flour could be used as prebiotic for further researches to develop dairy products to deliver probiotics.

Food Byproducts as Sustainable Ingredients for Innovative and Healthy Dairy Foods

“…Other byproducts from fruits, nuts, vegetables and cereals have also been used as sources of polyphenols for the development of fermented milks and yogurts. These byproducts included pomegranate seeds and peels, almond peels, hazelnut skins, olive pomace and rice bran [ 12 , 14 , 18 , 37 , 38 , 39 ].…”

“…Therefore, milk solids supplementation is a good practice to improve probiotic growth during fermentation and favor their viability in the product [ 134 ]. Rice bran, olive and wine pomace, cheese whey, pineapple, apple, banana and chestnut byproducts have been used for probiotic protection in fermented milks [ 13 , 14 , 17 , 18 , 19 , 22 , 27 , 28 , 30 ]. To our knowledge, the only attempt to use byproducts to promote probiotic viability in a different dairy matrix has been using wheat bran in cheese [ 54 ].…”

Bioactive Compounds of Chestnut (Castanea sativa Mill.)

“…Chestnuts are also a good source of minerals [5], vitamins, and fiber, which may exert beneficial effects in the regulation of metabolism [33]. In fact, there are currently enough evidences to support using chestnut flour as a good prebiotic, particularly considering its non-digestible ingredients, such as the oligosaccharides that might be fermented by probiotic bacteria like Lactobacilli and Bifidobacteria [34]. Additionally, chestnut contain organic acids such as oxalic, cis-aconitic, citric, ascorbic, malic, quinic, fumaric, glutamic, tartaric, pyruvic, and citric acids.…”

Metabolism analysis for enhanced nutritional profile of chestnuts subjected to anerobic solid‐state fermentation by probiotic lactic acid bacteria

“…Therefore, the development of in-depth processing technologies of chestnut is one of the important ways to have a positive influence on the chestnut market. In basis of their starchy nature, overproduction of chestnuts can be used in the formulation of alternative foods or for biotechnological purposes, such as making chestnut milk beverage (Ozcan, Yilmaz-Ersan, Akpinar-Bayizit, & Delikanli, 2016) and chestnut glutinous rice wine (Murado, Pastrana, Vázquez, Mirón, & González, 2008). Nowadays, people focus on functional foods that can give full play to the body's defensive function, regulate physiological rhythm, prevent diseases, and promote rehabilitation, rather than just satisfying appetite or nutrition.…”