Impact of Grape Seed Powder and Black Tea Brew on Lipid Digestion-An In Vitro Co-Digestion Study with Real Foods

Effects of two foods with bioactive constituents (black tea brew, BTB and grape seed powder, GSP) on lipid digestibility was studied. Lipolysis inhibitory effect of these foods was examined using two test foods (cream and baked beef) with highly different fatty acid (FA) composition. Digestion simulations were performed either using both gastric and pancreatic lipase, or only with pancreatic lipase according to the Infogest protocol. Lipid digestibility was assessed based on the bioaccessible FAs. Results showed the triacylglycerols containing short- and medium-chain FAs (SCFA and MCFA) are non-preferred substrates for pancreatic lipase; however, this is not characteristic for GL. Our findings suggest that both GSP and BTB primarily affect the lipolysis of SCFAs and MCFAs, because the dispreference of pancreatic lipase towards these substrates was further enhanced as a result of co-digestion. Interestingly, GSP and BTB similarly resulted in significant decrease in lipolysis for cream (containing milk fat having a diverse FA profile), whereas they were ineffective in influencing the digestion of beef fat, having simpler FA profile. It highlights that the characteristics of the dietary fat source of a meal can be a key determinant on the observed extent of lipolysis when co-digested with foods with bioactive constituents.

Impact of Operating Parameters on the Production of Nanoemulsions Using a High-Pressure Homogenizer with Flow Pattern and Back Pressure Control

The main objective of this study was to establish the relative importance of the main operating parameters impacting the formation of food-grade oil-in-water nanoemulsions by high-pressure homogenization. The goal of this unit operation was to create uniform and stable emulsified products with small mean particle diameters and narrow polydispersity indices. In this study, we examined the performance of a new commercial high-pressure valve homogenizer, which has several features that provide good control over the particle size distribution of nanoemulsions, including variable homogenization pressures (up to 45,000 psi), nozzle dimensions (0.13/0.22 mm), flow patterns (parallel/reverse), and back pressures. The impact of homogenization pressure, number of passes, flow pattern, nozzle dimensions, back pressure, oil concentration, emulsifier concentration, and emulsifier type on the particle size distribution of corn oil-in-water emulsions was systematically examined. The droplet size decreased with increasing homogenization pressure, number of passes, back pressure, and emulsifier-to-oil ratio. Moreover, it was slightly smaller when a reverse rather than parallel flow profile was used. The emulsifying performance of plant, animal, and synthetic emulsifiers was compared because there is increasing interest in replacing animal and synthetic emulsifiers with plant-based ones in the food industry. Under fixed homogenization conditions, the mean particle diameter decreased in the following order: gum arabic (0.66 µm) > soy protein (0.18 µm) > whey protein (0.14 µm) ≈ Tween 20 (0.14 µm). The information reported in this study is useful for the optimization of the production of food-grade nanoemulsions using high-pressure homogenization.

Carotenoids and Their Health Benefits as Derived via Their Interactions with Gut Microbiota

Carotenoids have been related to a number of health benefits. Their dietary intake and circulating levels have been associated with a reduced incidence of obesity, diabetes, certain types of cancer, and even lower total mortality. Their potential interaction with the gut microbiota (GM) has been generally overlooked but may be of relevance, as carotenoids largely bypass absorption in the small intestine and are passed on to the colon, where they appear to be in part degraded into unknown metabolites. These may include apo-carotenoids that may have biological effects because of higher aqueous solubility and higher electrophilicity that could better target transcription factors, i.e., NF-κB, PPARγ, and RAR/RXRs. If absorbed in the colon, they could have both local and systemic effects. Certain microbes that may be supplemented were also reported to produce carotenoids in the colon. Although some bactericidal aspects of carotenoids have been shown in vitro, a few studies have also demonstrated a prebiotic-like effect, resulting in bacterial shifts with health-associated properties. Also, stimulation of IgA could play a role in this respect. Carotenoids may further contribute to mucosal and gut barrier health, such as stabilizing tight junctions. This review highlights potential gut-related health-beneficial effects of carotenoids and emphasizes the current research gaps regarding carotenoid-GM interactions.

Enhancing the bioaccessibility of vitamin D using mixed micelles - An in vitro study

Vitamin-D deficiency is a global issue and a food fortification strategy may reduce deficiency levels. Mixed micelles (MM) are crucial to vitamin-D absorption in vivo and may enhance vitamin-D food fortification. This study compared the ability of MM based delivery systems to oil-in-water emulsions to improve vitamin-D bioaccessibility in vitro. Vitamin-D loaded emulsions were formed with olive or coconut oil alone or with added l-α-phosphatidylcholine, as well as two MM based systems. Particle size throughout digestion, fatty acid release, and vitamin-D bioaccessibility were measured. After digestion, particles in the MM size range (∼6-10 nm) were observed for emulsions but not for MM based systems. The bioaccessibility of vitamin-D in olive and coconut emulsions was 75% and 78%, respectively, and ∼ 90% with added l-α-phosphatidylcholine. Bioaccessibility for the MM alone was 93% and 90% when mixed with a protein/lactose base. Overall, MM show good potential as a delivery system for vitamin-D in vitro.

Evaluation of Pure Bile Salts in Place of Bile Extract in the Standardized INFOGEST Digestion Protocol for Quantification of Sterol Bioaccessibility

Improving standardized in vitro digestion protocols for phytosterols (PSs) is critical for understanding their bioaccessibility (BA) in food products and supplements. In this study, in vitro BA of phytosterol esters (PSEs) and free cholesterol (Ch) was compared under modified digestion conditions. The addition of Ch esterase (CE) to the INFOGEST model containing bovine bile resulted in a 70% increase in PS BA and an 18.5% reduction in Ch micellarization. Relative to the standardized INFOGEST model, substitution of pure bile salts (PBSs) did not significantly change PS BA or Ch micellarization. In the presence of CE, the substitution resulted in a 49.9% reduction in PS BA and a 13% increase in Ch micellarization. The differing results may be due to inhibitory effects of PBSs on the activity of intestinal enzymes, including CE. These results suggest that the INFOGEST model should include Ch esterase and the continued use of bile extract to evaluate PS BA.

Nano-enabled plant-based colloidal delivery systems for bioactive agents in foods: Design, formulation, and application

Consumers are becoming increasingly aware of the impact of their dietary choices on the environment, animal welfare, and health, which is causing many of them to adopt more plant-based diets. For this reason, many sectors of the food industry are reformulating their products to contain more plant-based ingredients. This article describes recent research on the formation and application of nano-enabled colloidal delivery systems formulated from plant-based ingredients, such as polysaccharides, proteins, lipids, and phospholipids. These delivery systems include nanoemulsions, solid lipid nanoparticles, nanoliposomes, nanophytosomes, and biopolymer nanoparticles. The composition, size, structure, and charge of the particles in these delivery systems can be manipulated to create novel or improved functionalities, such as improved robustness, higher optical clarity, controlled release, and increased bioavailability. There have been major advances in the design, assembly, and application of plant-based edible nanoparticles within the food industry over the past decade or so. As a result, there are now a wide range of different options available for creating delivery systems for specific applications. In the future, it will be important to establish whether these formulations can be produced using economically viable methods and provide the desired functionality in real-life applications.

Recent Advances in the Gastrointestinal Fate of Organic and Inorganic Nanoparticles in Foods

Inorganic or organic nanoparticles are often incorporated into foods to enhance their quality, stability, nutrition, or safety. When they pass through the gastrointestinal environment, the properties of these nanoparticles are altered, which impacts their biological effects and potential toxicity. Consequently, there is a need to understand how different kinds of nanoparticles behave within the gastrointestinal tract. In this article, the current understanding of the gastrointestinal fate of nanoparticles in foods is reviewed. Initially, the fundamental physicochemical and structural properties of nanoparticles are discussed, including their compositions, sizes, shapes, and surface chemistries. Then, the impact of food matrix effects and gastrointestinal environments on the fate of ingested nanoparticles is discussed. In particular, the influence of nanoparticle properties on food digestion and nutraceutical bioavailability is highlighted. Finally, future research directions are highlighted that will enable the successful utilization of nanotechnology in foods while also ensuring they are safe.

Plant-Based Colloidal Delivery Systems for Bioactives

The supplementation of plant-based foods and beverages with bioactive agents may be an important strategy for increasing human healthiness. Numerous kinds of colloidal delivery systems have been developed to encapsulate bioactives with the goal of improving their water dispersibility, chemical stability, and bioavailability. In this review, we focus on colloidal delivery systems assembled entirely from plant-based ingredients, such as lipids, proteins, polysaccharides, phospholipids, and surfactants isolated from botanical sources. In particular, the utilization of these ingredients to create plant-based nanoemulsions, nanoliposomes, nanoparticles, and microgels is covered. The utilization of these delivery systems to encapsulate, protect, and release various kinds of bioactives is highlighted, including oil-soluble vitamins (like vitamin D), ω-3 oils, carotenoids (vitamin A precursors), curcuminoids, and polyphenols. The functionality of these delivery systems can be tailored to specific applications by careful selection of ingredients and processing operations, as this enables the composition, size, shape, internal structure, surface chemistry, and electrical characteristics of the colloidal particles to be controlled. The plant-based delivery systems discussed in this article may be useful for introducing active ingredients into the next generation of plant-based foods, meat, seafood, milk, and egg analogs. Nevertheless, there is still a need to systematically compare the functional performance of different delivery systems for specific applications to establish the most appropriate one. In addition, there is a need to test their efficacy at delivering bioavailable forms of bioactives using in vivo studies.

Bioaccessibility of oil-soluble vitamins (A, D, E) in plant-based emulsions: impact of oil droplet size

We systematically investigated the impact of oil droplet diameter (≈0.15, 1.6, and 11 μm) on the bioaccessibility of three oil-soluble vitamins (vitamin A palmitate, vitamin D, and vitamin E acetate) encapsulated within soybean oil-in-water emulsions stabilized by quillaja saponin. Lipid digestion kinetics decreased with increasing droplet size due to the reduction in oil-water interfacial area. Vitamin bioaccessibility decreased with increasing droplet size from 0.15 to 11 μm: 87 to 39% for vitamin A; 76 to 44% for vitamin D; 77 to 21% for vitamin E. Vitamin bioaccessibility also decreased as their hydrophobicity and molecular weight increased, probably because their tendency to remain inside the oil droplets and/or be poorly solubilized by the mixed micelles increased. Hydrolysis of the esterified vitamins also occurred under gastrointestinal conditions: vitamin A palmitate (∼90%) and vitamin E acetate (∼3%). Consequently, the composition and structure of emulsion-based delivery systems should be carefully designed when creating vitamin-fortified functional food products.