Optimization of vitamins A and D3 loading in re-assembled casein micelles and effect of loading on stability of vitamin D3 during storage

Stability of vitamin A at critical points in pet-feed manufacturing and during premix storage

The objective of this research was to assess and quantify the potential vitamin A losses that occur during the manufacturing of pet feed and premix, as well as during their extended storage periods. This trial was conducted at a commercial feeder mill that utilized a standard commercial dog feed along with a corresponding vitamin-mineral premix. The calculated amount of vitamin A supplemented in the feed, in addition to the endogenous vitamins present in the ingredients, was adjusted to 18,000 IU/kg of feed. Five 500 g feed samples were collected at each of the predefined critical points throughout the manufacturing process (after mixing, milling, preconditioner, and extrusion/drying processes) to verify the stability of vitamin A during feed production. Additionally, various samples were collected at regular intervals of 30, 60, 90, 120, and 180 days during the storage of the premix to assess the stability of vitamin A. Vitamin A analyses in the samples were performed using high-performance liquid chromatography. The variables were assessed for normality using the Shapiro-Wilk test, followed by analysis of variance (ANOVA) and Tukey's test to compare the differences between the manufacturing process and premix shelf life. The statistical significance was set at 95%. The vitamin losses during the pre-conditioning process were 26%, and during the extrusion-drying processes, the losses were 34% when compared to the initial analyzed value. However, no differences were observed in other processes. There were no significant differences observed in recovered vitamin levels in the premix during its shelf-life (p = 0.484). The study indicated that the primary vitamin A losses in pet feed manufacturing processes occur during the pre-conditioning and drying/extrusion steps. However, it is worth noting that no significant losses of vitamin A were found during the premix storage phase.

Spray-freeze-drying as emerging and substantial quality enhancement technique in food industry

Spray freeze drying is an emerging technology in the food industry with numerous applications. Its ability to preserve food quality, maintain nutritional value, and reduce bulk make it an attractive option to food manufacturers. Spray freeze drying can be used to reduce the water content of foods while preserving the shelf life and nutritional value. Spray freeze-drying of food products is a process that involves atomizing food into small droplets and then flash-freezing them. The frozen droplets are then placed in a vacuum chamber and heated, causing the liquid to evaporate and the solid particles to become a dry powder. Spray freeze drying has become a valuable tool for the food industry through its ability to process a wide range of food products. This review's prime focus is understanding spray freeze-dried approaches and emphasizing their applicability in various products.

Recent advances in encapsulation of fat-soluble vitamins using polysaccharides, proteins, and lipids: A review on delivery systems, formulation, and industrial applications

Fat-soluble vitamins (FSVs) offer a range of beneficial properties as important nutrients in human nutrition. However, the high susceptibility to environmental conditions such as high temperature, light, and oxygen leads to the degradation of these compounds. This review highlights the different formulations underlying the encapsulation of FSVs in biopolymer (polysaccharide and protein) and lipid-based micro or nanocarriers for potential applications in food and pharmaceutical industries. In particular, the function of these carrier systems in terms of encapsulation efficiency, stability, bioavailability, and bio-accessibility is critically discussed. Recently, tremendous attention has been paid to encapsulating FSVs in commercial applications. According to the chemical nature of the active compound, the vigilant selection of delivery formulation, method of encapsulation, and final application (type of food) are the key important factors to be considered in the encapsulation of FSVs to ensure a high loading capacity, stability, bioavailability, and bio-accessibility. Future studies are recommended on the effect of different vitamin types and micro and nano encapsulate sizes on bioaccessibility and biocompatibility through in vitro/in vivo studies. Moreover, the toxicity and safety evaluation of encapsulated FSVs in human health should be evaluated before commercial application in food and pharmaceuticals.

Structural, Binding and Functional Properties of Milk Protein-Polyphenol Systems: A Review

Polyphenols (PP) are linked to health benefits (e.g., prevention of cancer, cardiovascular disease and obesity), which are mainly attributed to their antioxidant activity. During digestion, PP are oxidised to a significant degree reducing their bio-functionality. In recent years, the potential of various milk protein systems, including β-casein micelles, β-lactoglobulin aggregates, blood serum albumin aggregates, native casein micelles and re-assembled casein micelles, to bind and protect PP have been investigated. These studies have yet to be systematically reviewed. The functional properties of the milk protein-PP systems depend on the type and concentration of both PP and protein, as well as the structure of the resultant complexes, with environmental and processing factors also having an influence. Milk protein systems protect PP from degradation during digestion, resulting in a higher bioaccessibility and bioavailability, which improve the functional properties of PP upon consumption. This review compares different milk protein systems in terms of physicochemical properties, PP binding performance and ability to enhance the bio-functional properties of PP. The goal is to provide a comprehensive overview on the structural, binding, and functional properties of milk protein-polyphenol systems. It is concluded that milk protein complexes function effectively as delivery systems for PP, protecting PP from oxidation during digestion.

Ultrasound-Assisted Encapsulation of Anthraquinones Extracted from Aloe-Vera Plant into Casein Micelles

Aloe-vera extracted anthraquinones (aloin, aloe-emodin, rhein) possess a wide range of biological activities, have poor solubility and are sensitive to processing conditions. This work investigated the ultrasound-assisted encapsulation of these extracted anthraquinones (AQ) into casein micelles (CM). The particle size and zeta potential of casein micelles loaded with aloin (CMA), aloe-emodin (CMAE), rhein (CMR) and anthraquinone powder (CMAQ) ranged between 171–179 nm and −23 to −17 mV. The AQ powder had the maximum encapsulation efficiency (EE%) (aloin 99%, aloe-emodin 98% and rhein 100%) and encapsulation yield, while the whole leaf Aloe vera gel (WLAG) had the least encapsulation efficiency. Spray-dried powder (SDP) and freeze-dried powder (FDP) of Aloe vera showed a significant increase in size and zeta potential related to superficial coating instead of encapsulation. The significant variability in size, zeta potential and EE% were related to anthraquinone type, its binding affinity, and its ratio to CM. FTIR spectra confirmed that the structure of the casein micelle remained unchanged with the binding of anthraquinones except in casein micelles loaded with whole-leaf aloe vera gel (CMWLAG), where the structure was deformed. Based on our findings, Aloe vera extracted anthraquinones powder (AQ) possessed the best encapsulation efficiency within casein micelles without affecting its structure. Overall, this study provides new insights into developing new product formulations through better utilization of exceptional properties of casein micelles.

Vitamin A fortification: Recent advances in encapsulation technologies

Vitamin A is an essential micronutrient whose deficiency is still a major health concern in many regions of the world. It plays an essential role in human growth and development, immunity, and vision, but may also help prevent several other chronic diseases. The total amount of vitamin A in the human diet often falls below the recommended dietary allowance of approximately 900-1000 μ $ \umu $ g/day for a healthy adult. Moreover, a significant proportion of vitamin A may be degraded during food processing, storage, and distribution, thereby reducing its bioactivity. Finally, the vitamin A in some foods has a relatively low bioavailability, which further reduces its efficacy. The World Health Organization has recommended fortification of foods and beverages as a safe and cost-effective means of addressing vitamin A deficiency. However, there are several factors that must be overcome before effective fortified foods can be developed, including the low solubility, chemical stability, and bioavailability of this oil-soluble vitamin. Consequently, strategies are required to evenly disperse the vitamin throughout food matrices, to inhibit its chemical degradation, to avoid any adverse interactions with any other food components, to ensure the food is palatable, and to increase its bioavailability. In this review article, we discuss the chemical, physical, and nutritional attributes of vitamin A, its main dietary sources, the factors contributing to its current deficiency, and various strategies to address these deficiencies, including diet diversification, biofortification, and food fortification.

Recent updates on lentil and quinoa protein-based dairy protein alternatives: Nutrition, technologies, and challenges

Due to its high nutritional value and increasing consumption trends, plant-based proteins were used in a variety of dietary products, either in their entirety or as partial substitutions. There is indeed a growing need to produce plant-based proteins as alternatives to dairy-based proteins that have good functional properties, high nutritional values, and high protein digestibility. Among the plant-based proteins, both lentil and quinoa proteins received a lot of attention in recent years as dairy-based protein alternatives. To ensure plant-based proteins a success in food applications, food industries and researchers need to have a comprehensive scientific understanding of these proteins. The demand for proteins is highly dependent on several factors, mainly functional properties, nutritional values, and protein digestibility. Fermentation and protein complexation are recognised to be suitable techniques in enhancing the functional properties, nutritional values, and protein digestibility of these plant-based proteins, making them potential alternatives for dairy-based proteins.

Vitamin D Incorporation in Foods: Formulation Strategies, Stability, and Bioaccessibility as Affected by the Food Matrix

Inadequate intake of vitamin D is a global health issue related to severe diseases, mainly involving subjects with dark skin pigmentation, patients affected by malnutrition, malabsorption syndromes, or obesity, and elderly people. Some foods fortified with vitamin D have been tested in vivo, but fortification strategies with a global outreach are still lacking. This review is focused on food fortification with vitamin D, with the aim to collect information on (a) formulation strategies; (b) stability during processing and storage; and (c) in vitro bioaccessibility. Approaches to add vitamin D to various foods were analyzed, including the use of free vitamin D, vitamin D loaded in simple and double nanoemulsions, liposomes, casein micelles, and protein nanocapsules. Numerous studies were reviewed to elucidate the impact of food technologies on vitamin D’s stability, and mechanisms that lead to degradation were identified—namely, acid-catalyzed isomerization, radical-induced oxidation, and photo-oxidation. There is, however, a lack of kinetic data that allow for the prediction of vitamin D’s stability under industrial processing conditions. The roles that lipids, proteins, fibers, and antioxidants play in vitamin bioaccessibility have been clarified in various studies, while future needs include the design of specific food matrices that simultaneously achieve a balance between the long-term stability, bioaccessibility and, ultimately, in vivo functionality of vitamin D.

Casein Micelles as an Emerging Delivery System for Bioactive Food Components

Bioactive food components have potential health benefits but are highly susceptible for degradation under adverse conditions such as light, pH, temperature and oxygen. Furthermore, they are known to have poor solubilities, low stabilities and low bioavailabilities in the gastrointestinal tract. Hence, technologies that can retain, protect and enable their targeted delivery are significant to the food industry. Amongst these, microencapsulation of bioactives has emerged as a promising technology. The present review evaluates the potential use of casein micelles (CMs) as a bioactive delivery system. The review discusses in depth how physicochemical and techno-functional properties of CMs can be modified by secondary processing parameters in making them a choice for the delivery of food bioactives in functional foods. CMs are an assembly of four types of caseins, (α_s1, α_s2, β and κ casein) with calcium phosphate. They possess hydrophobic and hydrophilic properties that make them ideal for encapsulation of food bioactives. In addition, CMs have a self-assembling nature to incorporate bioactives, remarkable surface activity to stabilise emulsions and the ability to bind hydrophobic components when heated. Moreover, CMs can act as natural hydrogels to encapsulate minerals, bind with polymers to form nano capsules and possess pH swelling behaviour for targeted and controlled release of bioactives in the GI tract. Although numerous novel advancements of employing CMs as an effective delivery have been reported in recent years, more comprehensive studies are required to increase the understanding of how variation in structural properties of CMs be utilised to deliver bioactives with different physical, chemical and structural properties.

Innovative Delivery Systems Loaded with Plant Bioactive Ingredients: Formulation Approaches and Applications

Plants constitute a rich source of diverse classes of valuable phytochemicals (e.g., phenolic acids, flavonoids, carotenoids, alkaloids) with proven biological activity (e.g., antioxidant, anti-inflammatory, antimicrobial, etc.). However, factors such as low stability, poor solubility and bioavailability limit their food, cosmetics and pharmaceutical applications. In this regard, a wide range of delivery systems have been developed to increase the stability of plant-derived bioactive compounds upon processing, storage or under gastrointestinal digestion conditions, to enhance their solubility, to mask undesirable flavors as well as to efficiently deliver them to the target tissues where they can exert their biological activity and promote human health. In the present review, the latest advances regarding the design of innovative delivery systems for pure plant bioactive compounds, extracts or essential oils, in order to overcome the above-mentioned challenges, are presented. Moreover, a broad spectrum of applications along with future trends are critically discussed.

Interactions between caseins and food-derived bioactive molecules: A review

Caseins are recognized as safe for consumption, abundant, renewable and have high nutritional value. Casein molecules are found in different aggregation states and their multiple binding sites offer the potential for delivering biomolecules with nutritional and/or health benefits, such as vitamins, phytochemicals, fibers, lipids, minerals, proteins, peptides, and pharmaceutical compounds. In the present review, we highlight the interactions between caseins and food-derived bioactive molecules, with a special focus on the aggregation states of caseins and the techniques used to produce and study the particles used for delivering. Research on interactions between caseins-minerals and casein-pharmaceutical molecules are not included here. This review aims to support the development of new and innovative functional foods in which caseins can be used as designed delivery systems.

Utilization of Nanotechnology to Improve the Handling, Storage and Biocompatibility of Bioactive Lipids in Food Applications

Bioactive lipids, such as fat-soluble vitamins, omega-3 fatty acids, conjugated linoleic acids, carotenoids and phytosterols play an important role in boosting human health and wellbeing. These lipophilic substances cannot be synthesized within the human body, and so people must include them in their diet. There is increasing interest in incorporating these bioactive lipids into functional foods designed to produce certain health benefits, such as anti-inflammatory, antioxidant, anticancer and cholesterol-lowering properties. However, many of these lipids have poor compatibility with food matrices and low bioavailability because of their extremely low water solubility. Moreover, they may also chemically degrade during food storage or inside the human gut because they are exposed to certain stressors, such as high temperatures, oxygen, light, moisture, pH, and digestive/metabolic enzymes, which again reduces their bioavailability. Nanotechnology is a promising technology that can be used to overcome many of these limitations. The aim of this review is to highlight different kinds of nanoscale delivery systems that have been designed to encapsulate and protect bioactive lipids, thereby facilitating their handling, stability, food matrix compatibility, and bioavailability. These systems include nanoemulsions, solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), nanoliposomes, nanogels, and nano-particle stabilized Pickering emulsions.

Potential of Nanonutraceuticals in Increasing Immunity

Nutraceuticals are defined as foods or their extracts that have a demonstrably positive effect on human health. According to the decision of the European Food Safety Authority, this positive effect, the so-called health claim, must be clearly demonstrated best by performed tests. Nutraceuticals include dietary supplements and functional foods. These special foods thus affect human health and can positively affect the immune system and strengthen it even in these turbulent times, when the human population is exposed to the COVID-19 pandemic. Many of these special foods are supplemented with nanoparticles of active substances or processed into nanoformulations. The benefits of nanoparticles in this case include enhanced bioavailability, controlled release, and increased stability. Lipid-based delivery systems and the encapsulation of nutraceuticals are mainly used for the enrichment of food products with these health-promoting compounds. This contribution summarizes the current state of the research and development of effective nanonutraceuticals influencing the body's immune responses, such as vitamins (C, D, E, B12, folic acid), minerals (Zn, Fe, Se), antioxidants (carotenoids, coenzyme Q10, polyphenols, curcumin), omega-3 fatty acids, and probiotics.

Optimization and Formulation of Nanostructured and Self-Assembled Caseinate Micelles for Enhanced Cytotoxic Effects of Paclitaxel on Breast Cancer Cells

BACKGROUND

Paclitaxel (PTX) is a widely used anti-cancer drug for treating various types of solid malignant tumors including breast, ovarian and lung cancers. However, PTX has a low therapeutic response and is linked with acquired resistance, as well as a high incidence of adverse events, such as allergic reactions, neurotoxicity and myelosuppression. The situation is compounded when its complex chemical structure contributes towards hydrophobicity, shortening its circulation time in blood, causing off-target effects and limiting its therapeutic activity against cancer cells. Formulating a smart nano-carrier may overcome the solubility and toxicity issues of the drug and enable its more selective delivery to the cancerous cells. Among the nano-carriers, natural polymers are of great importance due to their excellent biodegradability, non-toxicity and good accessibility. The aim of the present research is to develop self-assembled sodium caseinate nanomicelles (NaCNs) with PTX loaded into the hydrophobic core of NaCNs for effective uptake of the drug in cancer cells and its subsequent intracellular release.

METHODS

The PTX-loaded micelle was characterized with high-performance liquid chromatography (HPLC), Fourier Transform Infrared Spectra (FTIR), High Resolution-Transmission Electron Microscope (HR-TEM), Field Emission Scanning Electron Microscope (FESEM) and Energy Dispersive X-Ray (EDX). Following treatment with PTX-loaded NaCNs, cell viability, cellular uptake and morphological changes were analyzed using MCF-7 and MDA-MB 231 human breast cancer cell lines.

RESULTS

We found that PTX-loaded NaCNs efficiently released PTX in an acidic tumor environment, while showing an enhanced cytotoxicity, cellular uptake and in-vivo anti-tumor efficacy in a mouse model of breast cancer when compared to free drug and blank micelles. Additionally, the nanomicelles also presented improved colloidal stability for three months at 4 °C and -20 °C and when placed at a temperature of 37 °C.

CONCLUSIONS

We conclude that the newly developed NaCNs is a promising carrier of PTX to enhance tumor accumulation of the drug while addressing its toxicity issues as well.

Physicochemical properties and bioavailability of naturally formulated fat-soluble vitamins extracted from agricultural products for complementary use for natural vitamin supplements

The purpose of the current study was to evaluate the physicochemical properties, digestive stability, storage stability, and intestinal absorption of formulated natural vitamins (FNV) by mixing fat-soluble vitamins extracted from agricultural products with their synthetic vitamin (SYNV) counterparts using a 6 to 4 ratio (w:w, dry weight). The FNV A, D, E, and K were evenly dispersed without crystal growth in the dispersion specifications for the functional tablet foods. The FNV A, D, E, and K had 89, 73, 65, and 36% of the digestive recovery, respectively, which was comparable to that of the SYNV. FNV D, E, and K were retained over 77%, but rapidly decreased to 15% after 6 months during accelerated storage at 25 30 and 35℃. The comparable radical scavenging capacity was found between the FNV and the SYNV. Results from the current study suggest that fat-soluble vitamins extracted from agricultural products could be reasonable complementary use for natural vitamin supplements.

Encapsulation of Vitamins A and E as Spray-Dried Additives for the Feed Industry

Encapsulated fat-soluble powders containing vitamin A (VA) and E (VE) were prepared as a feasible additive for extruded feed products. The effect of the encapsulating agents (Capsul-CAP®, sodium caseinate-SC) in combination with Tween 80 (TW) as an emulsifier and maltodextrin (MD) as a wall material on the physicochemical properties of emulsions and powders was evaluated. First, nanoemulsions containing MD:CAP:TW:VA/VE and MD:SC:TW:VA/VE were prepared and characterized. Then, powders were obtained by means of spray-drying and analyzed in terms of the product yield, encapsulation efficiency, moisture content, porosity, surface morphology, chemical structure, and thermal properties and thermo-oxidative/thermal stability. Results showed that although nanoemulsions were obtained for all the compositions, homogeneous microcapsules were found after the drying process. High product yield and encapsulation efficiency were obtained, and the presence of the vitamins was corroborated. The characteristics of the powders were mainly influenced by the encapsulating agent used and also by the type of vitamin. In general, the microcapsules remained thermally stable up to 170 °C and, therefore, the proposed encapsulation systems for vitamins A and E were suitable for the preparation of additives for the feed manufacturing through the extrusion process.

Vitamin D microencapsulation and fortification: Trends and technologies

Today, as per the latest medical reports available, majority of the population throughout globe is facing vitamin D (Vit D) deficiency. Even in sub-tropical countries like India and many others Vit D deficiency is highly prevalent despite the exuberant available sunshine (a major source of Vit D) throughtout the year. The reason could be attributed to an array of factors including socioeconomical, cultural and religious. Further, other than the sunlight, there are very limited sources of Vit D to fulfil the recommended dietary allowance of Vit D (RDA: 400-800 IU per day). A large proportion of Vit D is lost during food processing and storage due to environmental stress conditions such as temperature, pH, salt, oxygen and light. Vita D, an important micronutrient, is essentially required for the prevention of disorders such as neurodegenerative diseases, cardiovascular diseases, cancer etc. in addition to its traditional role in bone metabolism. Therefore, in order to meet the daily requirements of Vit D for human body, WHO has recognized fortification as the most efficient and safest method to address malnutrition. But there are innumerable chellenges involved during food fortification using Vit D as fortificants such as homogeneity into the food matrix, physico-chemical/photochemical degradation, loss during processing and storage, interactions with other components of food matrix resulting into change in taste, texture and appearance thus affecting acceptability, palatability and marketability. Fortification of Vit D into food products especially the ones which have an aqueous portion, is not simple for food technologist. Recent advances in nanotechnology offer various microencapsulation techniques such as liposome, solid-lipid particles, nanostructured lipid carriers, emulsion, spray drying etc. which have been used to design efficient nanomaterials with desired functionality and have great potential for fortification of fortificants like Vit D. The present review is an undate on Vit D, in light of its fortification level, RDA, factors affecting its bioavailability and various microencapsulation techniques adopted to develop Vit D-nanomaterials and their fate in food fortification.

Fabrication of nano-structured lipid carrier for encapsulation of vitamin D3 for fortification of 'Lassi'; A milk based beverage

A phase inversion based cold water dilution method was developed to encapsulate Vitamin D₃ (Vit D) in nano-structured lipid carrier (NLC) by blending caprylic-/capric triglyceride, Leciva S70 and Kolliphor HS®15, Vit D and sodium chloride. To optimize the process; a total of forty one formulations prepared by varying in their composition were tested for presence of NLC. Out of forty one formulations, only thirteen formulations resulted in NLC formation which were further evaluated for their physico-chemical attributes (particle size, zeta potential, transmittance, encapsulation efficiency and Vit D release). During principal component analysis using XLstats it was found that NLC-19, fabricated with 20% (v/v) Kolliphor, 20% (v/v) CCTG and 60% (v/v) water, 2.5% (w/v) Leciva, 2% (w/v) Vit D and 5% (w/v) sodium chloride was the most suitable for purpose of encapsulating Vitamin D. Hence, NLC-19 formulation was further taken up for stability studies under the following environmental stress conditions: (a) Temperature and humidity: accelerated condition: 45 ± 2 °C and RH 75 ± 5%, ambient condition: 25 ± 3 °C and RH 65 ± 5% and refrigerated condition: 6 ± 2 °C and RH 55 ± 5%, (b) pH: 3, 4, 5, 6, and 7, and (c) Ionic strength (NaCl concentration): 0 mM, 250 mM, 500 mM and 750 mM. The sensory evaluation of 'Lassi' (fortified with NLC-19) and its acceptability further confirmed the suitability of NLC-19 for the purpose of fortification of Vitamin D₃ in 'Lassi' (A milk based beverage).

A phase inversion based nanoemulsion fabrication process to encapsulate vitamin D3 for food applications

A phase inversion based nanoemulsion fabrication process was developed to encapsulate vitamin D₃ by blending caprylic-/capric triglyceride (CCTG), Leciva S70, Kolliphor® HS 15, vitamin D₃ and aqueous phase (sodium chloride solution). In order to find out nanoparticle formation zone (NFZ), a ternary diagram was plotted with 41 possible combinations of three components CCTG, Kolliphor® HS 15 and aqueous phase. Out of forty one, only twelve combinations resulted in formation of stable nanoemulsion where the composition varied between 10%-40% (v/v), 10%-25% (v/v) and 35%-80% (v/v) for Kolliphor, CCTG and water respectively. Further, these 12 nanoemulsions were investigated for their particle size, zeta potential, emulsion stability, encapsulation efficiency and release kinetics (simulated digestion) of vitamin D. The nanoemulsion (NE-20) fabricated with 30% (v/v) Kolliphor, 20% (v/v) CCTG and 50% (v/v) aqueous phase was found to be the most suitable with respected to zeta potential, emulsion stability and encapsulation efficiency and also demonstrated high bioavailability of vitamin D as compared to other combinations and hence was selected for further physiochemical studies. The selected nanoemulsion was also investigated for particle size and zeta potential and stability of vitamin D₃ retention under different environmental stress conditions (i) temperature and humidity: (a) accelerated condition: 45 ± 2 °C and RH 75 ± 5%, (b) ambient condition: 25 ± 3 °C and RH 65 ± 5% and (c) refrigerated condition: 6 ± 2 °C and RH 55 ± 5% (ii) pH (3-7) under refrigerated condition and (iii) ionic strength: NaCl concentration (0 mM, 250 mM, 500 mM and 750 mM) under crefrigerated condition. Fourier transform infrared spectroscopy and High Perfomance Liquid Chromatograpy technique were used to study physico-chemical stability of encapsulated vitamin D₃ in the developed nanoemulsion. The sensory evaluation also indicated the acceptability of the selected nanoemulsion the purpose of fortification for beverages.

Optimization of Flavonoid Extraction in Dendrobium officinale Leaves and Their Inhibitory Effects on Tyrosinase Activity

In order to establish the extraction technology of flavonoids from Dendrobium officinale leaves, a method combining Plackett–Burman design (PBD), steepest ascent design, and central composite design was developed to optimize the extraction of flavonoids. In addition, the tyrosinase activity inhibition of flavonoids was further tested in vitro. PBD results showed that ethanol concentration and number of extractions were key factors. Response surface methodology (RSM) indicated that the optimal extraction conditions were 78% ethanol concentration, six extraction times, 2 h, and 1:50 solid-liquid ratio. Under these conditions, the total flavonoid content could reach 35 mg/50 mL. In vitro tyrosinase experiment, the extracted total flavonoids had better inhibitory effect on tyrosinase activity than β-arbutin, and its inhibition rate for monophenolase and diphenolase exceeded 100% and 70%, respectively. These results indicate that RSM can effectively improve the extraction of flavonoids from Dendrobium officinale leaves and the flavonoids have the prospect of being applied to foods and cosmetics.

Formation of Stable Supramolecular Structure with β-Lactoglobulin-Derived Self-Assembling Peptide f1-8 and Bovine Micellar Caseins

The development of stable macromolecular structures with tailored functional properties in the dairy industry using innovative stabilizers is of great interest. The self-assembling peptide f1-8 (Pf1-8) derived from β-lactoglobulin was found to interact with whey proteins, consequently changing their physicochemical properties. The objective of the present work was to evaluate the interaction between Pf1-8 and micellar casein (CN) and the changes in their physicochemical properties and stability at different pH values (6.6-2.6) on model solutions containing CN and Pf1-8 at various ratios (1:1, 5:1, and 10:1) using spectrofluorimetry, TEM, SEC-HPLC, and SDS-PAGE analyses. No CN precipitation occurred for the solution at the 1:1 ratio even at pH values below 4.6. In all samples, CN was completely dissociated to primary casein particles (PCP) to form stable supramolecular structures strongly bound to peptide gels via hydrophobic interactions. Thus, a novel milk-protein-derived peptide responsible for stabilizing complex structures composed of CN was discovered.