Recent Innovations in Non-dairy Prebiotics and Probiotics: Physiological Potential, Applications, and Characterization

Non-dairy sources of prebiotics and probiotics impart various physiological functions in the prevention and management of chronic metabolic disorders, therefore nutraceuticals emerged as a potential industry. Extraction of prebiotics from non-dairy sources is economical and easily implemented. Waste products during food processing, including fruit peels and fruit skins, can be utilized as a promising source of prebiotics and considered "Generally Recognized As Safe" for human consumption. Prebiotics from non-dairy sources have a significant impact on gut microbiota and reduce the population of pathogenic bacteria. Similarly, next-generation probiotics could also be isolated from non-dairy sources. These sources have considerable potential and can give novel strains of probiotics, which can be the replacement for dairy sources. Such strains isolated from non-dairy sources have good probiotic properties and can be used as therapeutic. This review will elaborate on the potential non-dairy sources of prebiotics and probiotics, their characterization, and significant physiological potential.

Apple Pomace as a Sustainable Substrate in Sourdough Fermentation

Innovations range from food production, land use, and emissions all the way to improved diets and waste management. Global apple production has amounted to over 87 million tons/year, while 18% are processed, resulting in 20-35% (apple fruit fresh weight) apple pomace (AP). Using modern AP management, integrated knowledge in innovative fermentation demonstrates opportunities for reducing environmental pollution and integration into a circular economy. With this association in view, integrating AP flour during sourdough fermentation increases the nutritional value, highlighting a new approach that could guide innovative fermented foods. In this study, the wheat flour (WF) and AP flour were mixed at different ratios, hydrated with water (1:1 w/v), and fermented using a selective culture of Fructilactobacillus florum DSM 22689 and baker's yeast (single and co-culture). Sourdough fermentation was monitored and analyzed for 72 h. Results suggested that AP may be an important source of organic acids and fermentable sugars that increase nutritional sourdough value. AP flour addition in WF had a positive effect, especially in fermentations with 95% WF and 5% AP, mainly in co-culture fermentation.

Lactic Acid Bacteria-Fermentable Cereal- and Pseudocereal-Based Beverages

Plant beverages are becoming more popular, and fermented cereal- or pseudocereal-based beverages are increasingly used as alternatives for fermented products made from cow milk. This review aimed to describe the basic components of cereal- or pseudocereal-based beverages and determine the feasibility of fermenting them with lactic acid bacteria (LAB) to obtain products with live and active LAB cells and increased dietary value. The technology used for obtaining cereal- or pseudocereal-based milk substitutes primarily involves the extraction of selected plant material, and the obtained beverages differ in their chemical composition and nutritional value (content of proteins, lipids, and carbohydrates, glycemic index, etc.) due to the chemical diversity of the cereal and pseudocereal raw materials and the operations used for their production. Beverages made from cereals or pseudocereals are an excellent matrix for the growth of LAB, and the lactic acid fermentation not only produces desirable changes in the flavor of fermented beverages and the biological availability of nutrients but also contributes to the formation of functional compounds (e.g., B vitamins).

Teff-Based Probiotic Functional Beverage Fermented with Lactobacillus rhamnosus and Lactobacillus plantarum

Consumers are demanding healthier foods, and the increasing drawbacks associated with dairy-based products have driven efforts to find plant-based probiotic alternatives. Consequently, this study aimed to evaluate the suitability of a teff-based substrate for delivering the potential probiotics, Lactobacillus rhamnosus GG (LGG) and Lactobacillus plantarum A6 (LA6) with a view to developing probiotic functional beverages. Single-strain and mixed-strain fermentations were performed without any pH control. In single-strain fermentation, LA6 grew to 8.157-8.349 log cfu/mL. Titratable acidity (TA) and pH were measured between 0.513-1.360 g/L and 4.25-3.91, respectively. The explored optimum variables were fermentation time (15 h) and inoculum (6 log cfu/mL). As a result of fermentation, maltose and glucose decreased, but lactic and acetic acids increased. In mixed-strain fermentation, LGG and LA6 were able to grow to 8.247 and 8.416 log cfu/mL, respectively. The pH, TA, lactic, and acetic acids varied between 6.31-3.92, 0.329-1.501 g/L, 0-1672 mg/L, and 20-231.5 mg/L, respectively. In both fermentations, microbial growth reached the stationary phase close to a pH of 4.21-4.82 while sugars were not consumed completely. Less than 5% ethanol was detected, which indicated a non-alcoholic beverage. A combination of the two evaluated lactobacilli strains reduced fermentation time. In conclusion, a substrate made of whole grain teff flour without any supplement could be used as a substrate to produce functional probiotic beverages.

Can pseudocereals modulate microbiota by functioning as probiotics or prebiotics?

Amaranth, quinoa, and buckwheat, known as pseudocereals, have been consumed since ancient times and are considered sacred in most cultures. Their grains can be used as cereals for breakfast or mixed with other grains in meals and their health-enhancing effects have been investigated more in recent years. They have an antioxidant effect and their nutrient profiles are enriched with processing techniques such as sprouting and fermentation. Their suitability to different processing techniques and the rapid increase in microbiota researches highlighted the probiotic/prebiotic effects of pseudocereals. Using cultures or naturally fermented amaranth, quinoa and buckwheat exhibited good substrate properties for probiotic bacteria, especially for Lactobacillus strains. Studies have found that they reduce the number of pathogen microorganisms, increase the synthesis of short-chain fatty acids due to their prebiotic effects. Also the number of bacterial colonies do not change during the storage period and their organoleptic properties are revealed. It has been determined that pseudocereals decrease Ruminococcacea, Lachnospiraceae, Helicobacteracea, Clostridium, Escherichia and increase Peptoclostridium, Prevotellaceae, Lactobacillus, Bifidobacterium, Enterococcus, and Eubacteriaceae. Due to these effects, they are considered as good sources for synbiotic formulations to be developed for the treatment of dysbiosis, obesity, Celiac Disease, lactose intolerance, inflammatory bowel diseases and inflammation-mediated chronic disorders.

Non-Dairy Fermented Beverages as Potential Carriers to Ensure Probiotics, Prebiotics, and Bioactive Compounds Arrival to the Gut and Their Health Benefits

In alignment with Hippocrates' aphorisms "Let food be your medicine and medicine be your food" and "All diseases begin in the gut", recent studies have suggested that healthy diets should include fermented foods to temporally enhance live microorganisms in our gut. As a result, consumers are now demanding this type of food and fermented food has gained popularity. However, certain sectors of population, such as those allergic to milk proteins, lactose intolerant and strict vegetarians, cannot consume dairy products. Therefore, a need has arisen in order to offer consumers an alternative to fermented dairy products by exploring new non-dairy matrices as probiotics carriers. Accordingly, this review aims to explore the benefits of different fermented non-dairy beverages (legume, cereal, pseudocereal, fruit and vegetable), as potential carriers of bioactive compounds (generated during the fermentation process), prebiotics and different probiotic bacteria, providing protection to ensure that their viability is in the range of 106-107 CFU/mL at the consumption time, in order that they reach the intestine in high amounts and improve human health through modulation of the gut microbiome.

Modeling of lactic acid fermentation of soy formulation with Lactobacillus plantarum HM1

Lactic acid bacteria alone or with special adjunct probiotic strains are inevitable for the preparation of various specific functional foods. Moreover, because of their growth and metabolism, the final products are preserved for a certain time. Thus, growth dynamics of the lactic acid bacteria of the Fresco DVS 1010 culture ( Lactococcus lactis spp. lactis, Lactococcus lactis spp. cremoris, Streptococcus salivarius spp. thermophilus) during liquid-state fermentation of soya mashes and pH values within the process were analyzed in this study. Although milk is the most typical growth medium for the lactic acid bacteria, presumable viable counts of Fresco culture reached levels 109 CFU ml-1 after 8 h, representing 2-3 log increase in comparison to initial state (specific growth rates ranged from 1.06 to 1.64 h-1). After 21 days of storage period, the pH levels in the products were reduced to 4.50-4.70, representing a decrease of about 1.5-1.7 units. All prepared soybean products contained detectable amounts of raffinose-series oligosaccharides (0.25-0.68 g per 100 g) that were reduced in average by about 30.5% during period of 21 days.

Traditional Cereal Food as Container of Probiotic Bacteria “Lb. rhamnosusGG”: Optimization by Response Surface Methodology

This research paper aims at optimizing three parameters involved in solid state fermentation (SSF) usingLactobacillus rhamnosusGG (LGG) to improve a traditional cereal food “Bsissa” in order to elaborate a new probiotic fermented breakfast cereal. A Box-Behnken experimental design was used and the optimal fermentation conditions were liquid to solid ratio: 1.2 (vw−1), fermentation time: 12 h, and sucrose concentration: 10.48 g (100 g DM)−1. Under these conditions, the viable LGG cells, the free amino nitrogen content, and the total acidity were obtained to be9.1 log10⁡(cfu g-1), 12.95 (mg g−1), and 6.46 (μmol g−1), respectively. After three weeks of refrigerated storage, the viability of LGG in the fermented Bsissa was8.23 log10⁡(cfu g-1). This study shows a new possibility to make an acceptable nonfermented dairy product based mainly on cereals, leguminous plants, spices, and aromatic herbs, which are suitable substrates able to support the high probiotic viability.