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Encapsulation is a commonly used tool in the pharmaceutical and nutraceutical fields to protect the compound of interest from adverse environmental conditions (i.e., production process, gastrointestinal transit, immune defense) or to ensure a target or controlled release of an active principle. However, capsules can also be used as reactors, by which probiotics can carry out a fermentation with improved process performances. In the present work, hydrolyzed oatmeal capsules were developed as mini-bioreactors, segregating the probiotic strain in active fermentation and allowing the metabolite release. The aim was to study how composition can influence the ability to ferment and the confinement of microorganisms. Four different capsules formulations were studied varying CaCl2 and alginate concentrations [(i) 0.5% alginate-0,1 M CaCl2; (ii) 1% alginate-1 M CaCl2; (iii) 1% alginate-3 M CaCl2; (iv) 1% alginate-5 M CaCl2]. The capsules were suspended in the same hydrolyzed oatmeal suspension used to produce them and left to ferment at 37°C for 24h. Microbiological and chemical analyses were carried out on both capsules and external liquids. An increase in the bacterial concentration of about 3 logs was recognized for all the first three formulations in the capsules, while a growth inhibition was observed for the (iv) formulation, the only formulation for which microorganism confinement was also noted. The highest lactic acid production (15.9 g/L) was observed for the (ii) formulation, while the lowest one was also recorded for formulation (iv). Optical analyses confirmed the different structural characteristics of the capsules. [ABSTRACT FROM AUTHOR]

Encapsulation is an innovative promising technique in the field of biotechnology, both for confining live microorganisms to promote their viability during processing and for the target delivery in the gastrointestinal tract, and for trapping active metabolites produced during a fermentation process within a carrier material, allowing their gradual release. During this work, a probiotic strain, Lacticaseibacillus paracasei CBA L74, was encapsulated using a hydrolyzed oatmeal suspension as a prebiotic carrier, by extrusion technique with CaCl2 a (1M) and alginate (1% w/v). The mini-bioreactors obtained were suspended in three different external liquids, (the same hydrolyzed oatmeal suspension used for the capsule production; a hydrolyzed oatmeal suspension with a modified pH equal to 3.3, and a hydrolyzed oatmeal suspension formulated by adding a specific concentration of dead bacteria) to evaluate whether the external liquid can help the confinement of the bacteria in the capsules. For this purpose, the fermentation process was carried out at 37°C for 24h; both capsules and external liquids were characterized by microbiological and chemical analyses. The maximum bacterial growth ( 109 CFU/mL) was reached in all the capsules, except for those suspended in the formulation with a modified pH where a bacterial charge of 3.5 x 108 CFU/mL was obtained; in any case, the bacterial confinement was not obtained. The highest lactic acid concentration (15.9 g/L) was observed for the capsules suspended in the same oatmeal suspension used for encapsulation, while the lowest one was obtained in the external oatmeal liquid with a modified pH. [ABSTRACT FROM AUTHOR]

Recently, the role of the gut microbiota in metabolic health, immunity, behavioral balance, longevity, and intestine comfort has been the object of several studies from scientific communities. They were encouraged by a growing interest from food industries and consumers toward novel fermented ingredients and formulations with powerful biological effects, such as pre, pro, and postbiotic products. Depending on the selected strains, the operating conditions, the addition of suitable reagents or enzymes, the equipment, and the reactor configurations, functional compounds with high bioactivity, such as short-chain fatty acids, gamma-aminobutyric acid, bioactive peptides, and serotonin, can be enhanced and/or produced through fermentation of several vegetable matrices. Otherwise, their formation can also be promoted directly in the gut after the dietary intake of fermented foods: In this case, fermentation will aim to increase the content of precursor substances, such as indigestible fibers, polyphenols, some amino acids, and resistant starch, which can be potentially metabolized by endogenous gut microorganisms and converted in healthy molecules. This review provides an overview of the main functional components currently investigated in literature and the associated gut health benefits. The current state of the art about fermentation technology as a promising functionalization tool to promote the direct or indirect formation of gut-health-enhancing components was deepened, highlighting the importance of optimizing microorganism selection, system setups, and process conditions according to the target compound of interest. The collected data suggested the possibility of gaining novel functional food ingredients or products rich in functional molecules through fermentation without performing additional extraction and purification stages, which are needed when conventional culture broths are used. [ABSTRACT FROM AUTHOR]

In the actual scenario, characterised by a global crisis, sustainability is not a minor player; it has a crucial role in the global outlook. Sustainability at the environmental level evolves in recycling, reusing, upcycling, and no squandering policies. Nowadays, the incessant, excessive, and growing use of plastic has a strong impact on global warming and represents a threat to the Oceans and the Planet. The paper industry can play a crucial role in addressing this emergency, by substituting mostly or totally (where it is possible) this impacting material. To confer paper materials the same plastic resistances, some additives could be used. In detail, the feasibility of upcycling silk waste was investigated and paper products containing silk fibers were formulated to realize worthy substitutes for plastic materials. These alternative fibers were inserted as a filler (20%wt. and 30% wt) in the cellulosic matrix and the resulting suspension was used to produce special papers for packaging. Silk, in both cases, was subjected to a chemical pretreatment with NaOH before paper sheet formation, which guaranteed an appropriate silk-cellulose interaction, without compromising the final chemichal-physical properties. Moreover, the sheets were subjected to non-destructive and destructive testing, which confirmed respectively their high-quality degree and good mechanical resistances. Silk confers special characteristics, in particular, the resulting sheets with silk were fluffier to the touch than the reference in pure cellulose. The resulting materials can be used as semi-finished products to obtain more sustainable paper-based packaging materials and promote a plastic-to-paper transition. [ABSTRACT FROM AUTHOR]

In recent years, scientific research and industries have been focusing on the application of biological treatments aimed at imparting functional properties to waste products from food industries according to the principles on which the circular economy model is based, namely, the recovery, valorisation, and reuse of wastes. This work aimed at exploring the possibility of valorising waters from the blanching process of dried navy beans through lactic acid fermentation using Lacticaseibacillus paracasei CBA L74 as a starter. Two samples at different solid concentrations (0.75 °Bx and 1.25 °Bx) were fermented, and, in both cases, a bacterial load of 8 Logs and a lactic acid concentration of approximately 1.3 g/L were reached, despite the lack of nutrients. An unusual pH trend, characterised by an initial decrease and unexpected final rise, was observed during the fermentation of both samples: simultaneously, an increase in protein content was observed, suggesting that the proteolytic action of the microorganism could be responsible for the release of pH-increasing substances. In both cases, a slight increase in total polyphenols (approximately 23.3–33.72%) and flavonoids (approximately 42.3–52%) due to fermentation was observed, with a corresponding improvement in antioxidant capacity (approximately 25.32–37.72%). A significant increase in saponin concentration was determined for the most concentrated blanching water (from 2.87 ± 0.28 to 6.68 ± 0.69 mgOAE/mL), leading to an improvement in foaming properties and an enhanced capacity to produce stable emulsions. The obtained results confirmed the possibility of reducing water consumption from blanching operations, as well as finding valorisation opportunities for this side stream through a safe and inexpensive fermentation treatment. [ABSTRACT FROM AUTHOR]

Lactic acid fermentation of legume-based matrices has been gaining an increasing interest in recent years to produce pro- and post-biotic functional foods at high protein content. The optimization of the main process conditions is necessary to improve bacterial growth, microbial metabolic activity, thus the consequent functional properties of the resulting fermented products. A preliminary study of feasibility about the potential of using a leguminous substrate as growth medium for Lactobacillus paracasei CBA L74 was already conducted in previous experimentations. In this work, the effect of improving mixing conditions of a cooked navy bean suspension during the lactic acid fermentation process was investigated and some chemical and physical properties of the resulting fermented products were studied to verify their potential application as functional ingredients in food formulations. The mixing system was optimized by designing an impeller that guarantees a more homogeneous distribution of nutrients and avoids concentration gradients that could inhibit the microorganism proliferation. Bacterial growth, lactic acid production, sugar, and starch consumption were compared with those obtained during previous experimentations carried out with a different impeller. The major availability of nutrients in the fermenting medium reached with the customized impeller allowed a faster achievement of the maximum microbial load (1×109 CFU/mL after 14 h of process) and a lower doubling time of 1.53 h. Furthermore, fermentation led to a reduction in water absorption, oil binding, and foam capacity of the fermented bean powders. Total phenolic and flavonoid content and their antioxidant capacity were not influenced by the fermentation process itself but favored by the previous thermal treatment of sterilization. [ABSTRACT FROM AUTHOR]

Black garlic (BG) can be found on menus everywhere, but this unique ingredient isn’t anything new. Traditional and natural BG is, simply put, the product of aging regular garlic bulbs leaving them for weeks and months at typical ambient temperatures and high humidity (about 40°C and 90-100% RH) without addition of any preservatives achieving its typical colour and sticky texture. In this work, in order to speed up the complex Maillard reactions at the base of the organoleptic, textural and nutritional characteristics of the BG. The optimal process conditions and time were determined and the time of the browning of the cloves have been reduced considerably; the tests to produce black garlic are carried out with different temperature values (70-80-90°C) and different relative humidity values (70-80-90% RH). The process time can be consistently reduced ranging between 2-4 days. Samples produced at higher temperature (90°C) and low humidity (70%RH) were dry, friable and with low content of water while samples produced at high humidity (80-90%RH) and low temperature presented a gum-like consistency. The allicin has been totally transformed by the treatment losing the typical smell of the garlic. Moreover, there is also an increasing of the polyphenols and flavonoids contents if compared to the raw fresh garlic (respectively ranging between 32 -26 and 18 -13 mgGAE/gdr). Higher fructose content (250÷ 500 mg / g dry) - that confers sweetness - was measured at the end of the thermal processing as a possible consequence of the hydrolysis of long chain of the fructans. [ABSTRACT FROM AUTHOR]