Carotenoid Bioaccessibility Research Articles

Bioaccessibility and intestinal uptake of carotenoids from microalgae Scenedesmus obliquus

This study aimed to investigate the carotenoids bioaccessibility of the whole dried biomass (WDB), wet ultrasonicated biomass (WUB), and isolated carotenoid extract (ICE) from Scenedesmus obliquus using an in vitro digestion model. Also, the intestinal uptake of ICE was investigated. The samples were submitted to in vitro digestion model according to the INFOGEST protocol, and Caco-2 cells determined the intestinal uptake. Carotenoids were determined by HPLC-PDA-MS/MS. The results showed that the bioaccessibility was improved according to the type of product (ICE > WUB > WDB). The all-trans-canthaxanthin (99.07%), all-trans-α-carotene (48.94%), and all-trans-β-cryptoxanthin (31.87%) were the most bioaccessible compounds in ICE, WUB, and WDB, respectively. Due to the ICE showed the best bioaccessibility, it was considered the most efficient condition and subjected to uptake by intestinal cells. ICE uptake demonstrated that the most abundant carotenoids in Caco-2 cells were all-trans-β-crocoxanthin (17.34%), followed by all-trans-echinenone (7.55%). In contrast, all-trans-lutein (0.88%) was the least abundant in cells. The xanthophylls were uptake in greater proportion than carotenes. Finally, the results showed the significant influence of the product nature in promoting the bioaccessibility of microalgae carotenes and xanthophylls.

Chitin nanocrystals reduce lipid digestion and β-carotene bioaccessibility: An in-vitro INFOGEST gastrointestinal study

Engineered nanoscale materials (ENMs) are being intentionally added to some food and beverage products to achieve novel or improved functional attributes. However, there is still a relatively poor understanding of the behavior of many types of ENMs within the human gastrointestinal tract (GIT). In this study, the impact of chitin nanocrystals on the gastrointestinal fate of a model emulsion was investigated using a standardized in vitro digestion model (INFOGEST), which is now widely used by food and nutrition scientists. The results obtained with the INFOGEST model were compared to those obtained with another commonly used static in vitro digestion model. Moreover, the impact of nanochitin dose on the digestibility and bioaccessibility of model food emulsions was examined: β-carotene-loaded corn oil-in-water emulsions stabilized by a non-ionic surfactant (Tween 80). In agreement with the results obtained using an earlier in vitro digestion model, we found that the presence of nanochitin reduced lipid digestion and β-carotene bioaccessibility. However, the magnitude of these effects was considerably less for the INFOGEST model, which was attributed to the higher levels of pancreatic lipases and lower levels of calcium ions used. Overall, this study shows that nanochitin may be used to retard lipid digestion (which is useful for creating foods that induce satiety), but that it also suppresses carotenoid bioaccessibility (reducing the nutritional value of foods). Consequently, food formulators must carefully consider all the potential impacts of edible nanoparticles when using them as functional ingredients in foods.

Bioaccessibility of carotenoids and antioxidant capacity of seed-used pumpkin byproducts powders as affected by particle size and corn oil during in vitro digestion process

Powders made from seed-used pumpkin flesh (SUPF) are potential sources of carotenoids. In this study, unexplored effects of particle size and corn oil on bioaccessible amounts of carotenoids and antioxidant capacity of SUPF powders during in vitro digestion process were investigated. Overall, total carotenoid relative bioaccessibility (TCRB) of 100 mesh-sized powder (100 MP, 15.46%) was higher than that of 18 mesh-sized powder (18 MP, 12.94%). With the addition of 2% corn oil, TCRB increased 108.35% (18 MP) and 88.55% (100 MP), respectively. Lutein (≥27160 µg/100 g) and β-carotene (≥5192 µg/100 g) were main carotenoid monomers in SUPF and significantly correlated with DPPH radical scavenging activity of digestive supernatant (p < 0.05). Notably, DPPH radical scavenging activity of 18 MP increased 96.54% with corn oil. These results implied that smaller particle size and oil addition could improve bioaccessible amounts of carotenoids and antioxidant capacity of SUPF powders.

Concentrates from citrus juice obtained by crossflow microfiltration: Guidance of the process considering carotenoid bioaccessibility

This work focused on an eco-friendly process to concentrate carotenoids from a citrus juice formulated with clementine and pink grapefruit. It is based on crossflow microfiltration associated with enzymatic liquefaction, diafiltration and pasteurization. The aim was to evaluate the impact of the main operating conditions on the process performance and on the nutritional quality of the final concentrate taking into account the bioaccessibility of β-carotene, β-cryptoxanthin and lycopene. First, the best enzyme/pressure/membrane combination was chosen in order to maximize permeate flux during microfiltration (>100 kg.h−1.m−2 at 2.6 bar with tubular inorganic membranes). Second thanks to a Plackett-Burman experimental design applied to the whole process, we showed the enzymatic dose was the most impacting parameter on carotenoid bioaccessibility and it decreased it. An optimal dose of enzyme had to be defined in order to obtain a good compromise between the process performance and the nutritional quality of the citrus concentrate.

Factors impacting lipid digestion and nutraceutical bioaccessibility assessed by standardized gastrointestinal model (INFOGEST): Emulsifier type

This paper is part of a series examining the impact of the main factors influencing lipid digestion and nutraceutical bioaccessibility in β-carotene-loaded oil-in-water emulsions using the harmonized INFOGEST simulated gastrointestinal model. Here, the impact of emulsifier type was examined since food emulsions and nutraceutical delivery systems are often stabilized by various types of emulsifier. The INFOGEST method was adopted to investigate the in vitro gastrointestinal fate of emulsions stabilized by five kinds of food-grade emulsifier representing different classes: synthetic surfactants (Tween 20); natural surfactants (quillaja saponin); proteins (caseinate); polysaccharides (gum arabic); and phospholipids (soy lysolecithin). Microfluidization produced emulsions with small droplet sizes for all emulsifiers, except soy lysolecithin. Within the gastrointestinal model, the caseinate-coated oil droplets had the worst gastric stability, with severe droplet flocculation and coalescence occurring in the stomach. The fraction of the lipid phase that had been digested by the end of the gastrointestinal model was considerably lower for the emulsions stabilized by soy lysolecithin (93%) or caseinate (93%), than those stabilized by gum arabic (99%), quillaja saponin (111%) or Tween 20 (117%). This effect was attributed to lower surface area of lipids available for lipase to attach to for the lysolecithin and caseinate emulsions. The overall bioaccessibility of the β-carotene increased in this order: lysolecithin (25%) < gum arabic (51%) < caseinate (55%) < quillaja saponin (56%) < Tween 20 (62%). The impact of emulsifier type on carotenoid bioaccessibility was ascribed to various factors: (i) some emulsifiers inhibited lipid digestion and so a fraction of the β-carotene remained inside the undigested droplets and the mixed micelle phase had less solubilization capacity, i.e., lysolecithin, and caseinate; (ii) some emulsifiers protected β-carotene from chemical degradation, i.e., lysolecithin and caseinate; and (iii) some emulsifiers promoted sedimentation of the β-carotene-loaded micelles, i.e., lysolecithin. These results suggest that food emulsion behavior in the human gut may be influenced by the nature of the emulsifier employed, which is important knowledge when creating functional food and beverage products.

Addition of either gastric lipase or cholesterol esterase to improve both β-cryptoxanthin ester hydrolysis and micellarization during in vitro digestion of fruit pulps

Using the INFOGEST in vitro digestion protocol adapted to carotenoids, the impact of additional rabbit gastric lipase (RGL) on the hydrolysis extent of β-cryptoxanthin esters was evaluated for the first time, and compared with the addition of porcine cholesterol esterase (CEL). Both the modifications increased the hydrolysis of (all-E)-β-cryptoxanthin esters from mandarin and peach pulps, although the outcomes were different. Addition of RGL consistently increased the average hydrolysis extent from 55.2% to 59.5% in mandarin pulp and from 22.7% to 48.8% in peach pulp (p < 0.05). The addition of CEL produced lower hydrolysis extents, i.e., 58.5% in mandarin (not statistically significant) and 28.4% in peach (p < 0.05), compared to those obtained with RGL. The hydrolysis extent positively correlated with the carotenoid ester concentration in both matrices. Bioaccessibility values were higher in mandarin pulp (range 32–34%) compared to those in peach pulp (range 16–21%), and were associated with the hydrolysis extent of the carotenoid esters during digestion. Addition of RGL and CEL produced no significant (p < 0.05) effect on the overall carotenoid bioaccessibility values of mandarin, while positively affected those in peach. Altogether these results corroborate that the hydrolysis extent of xanthophyll esters limits bioaccessibility. Additionally, hydrophobicity of the carotenoid inversely correlates with micellarization, as free (all-E)-xanthophylls micellarized in a higher extent compared to (all-E)-β-carotene and xanthophyll esters. The new information of our results is that the addition of rabbit gastric lipase substantially contributes to the hydrolysis of β-cryptoxanthin esters from fruit pulps, and consequently, to increase carotenoid bioaccessibility, being even more effective than CEL.

Chemistry and biochemistry of dietary carotenoids: bioaccessibility, bioavailability and bioactivities

Carotenoids are one of the major food bioactives that provide humans with essential vitamins and other critically important nutrients that contribute to the maintenance of human health. This review provides a summary of the most current literature data and information on most recent advances in dietary carotenoids and human health research. Specifically, it addresses the occurrence and distribution of carotenoids in different dietary sources, the effect of food processing and impact of gastrointestinal digestion on the bioaccessibility, bioavailability and bioactivities of dietary carotenoids. Emphasis is placed on the antioxidant and anti-inflammatory effects of carotenoids and their optical/geometric isomers and ester forms, and the molecular mechanisms behind these actions. A particular focus is also on the modulatory ability of carotenoids on biomarkers related to low-grade inflammation, immune response and gut health.

Impact of Different Pasteurization Techniques and Subsequent Ultrasonication on the In Vitro Bioaccessibility of Carotenoids in Valencia Orange (Citrus sinensis (L.) Osbeck) Juice.

The effects of traditional pasteurization (low pasteurization, conventional pasteurization, hot filling) and alternative pasteurization (pulsed electric fields, high pressure processing), followed by ultrasonication on the carotenoid content, carotenoid profile, and on the in vitro carotenoid bioaccessibility of orange juice were investigated. There was no significant difference in the total carotenoid content between the untreated juice (879.74 µg/100 g juice) and all pasteurized juices. Significantly lower contents of violaxanthin esters were found in the high thermally-treated juices (conventional pasteurization, hot filling) compared to the untreated juice, owing to heat-induced epoxy-furanoid rearrangement. The additional ultrasonication had almost no effects on the carotenoid content and profile of the orange juices. However, the in vitro solubilization and the micellarization efficiency were strongly increased by ultrasound, the latter by approximately 85.3–159.5%. Therefore, among the applied processing techniques, ultrasonication might be a promising technology to enhance the in vitro bioaccessibility of carotenoids and, thus, the nutritional value of orange juice.

Influence of high pressure homogenization and pasteurization on the in vitro bioaccessibility of carotenoids and flavonoids in orange juice.

Production of high-quality healthy foods through sustainable methodologies is an urgent necessity. High pressure homogenization (HPH) is an interesting alternative to obtain premium citrus juices, but its effects on bioactive compounds are unclear. There was studied the influence of HPH (150MPa) and pasteurization (92°C for 30s and 85°C for 15s) processing on physicochemical properties and in vitro bioaccessibility of carotenoids and flavonoids in orange juices. Regarding fresh juice, physicochemical properties of samples remained unchanged although cloudiness was improved by homogenization. Pasteurization did not affect total carotenoids content and retinol activity equivalents (RAE) of juices whereas homogenization yielded a significant reduction (1.37 and 1.35-fold, respectively). Interestingly, particle size reduction from homogenization drastically enhanced (about 5-fold) bioaccessibility of carotenoids including hardly bioaccessible epoxycarotenoids, finding unaltered rates in pasteurized samples. Bioaccessibility of flavonoids was constant in all cases. Results can promote HPH as an efficient option to obtain health-enhanced foods.

Consumption patterns, perceptions and total carotenoids, iron and zinc contents of yellow flesh cassava

Abstract. Duah EA, Steiner-Aseidu M, Danquah AO. 2018. Consumption patterns, perceptions, and total carotenoids, iron, and zinc contents of yellow flesh cassava. Biofarmasi J Nat Prod Biochem 18: 13-28. The main objective was to investigate consumption patterns of white cassava, knowledge, perceptions and the nutritive profiles of yellow flesh cassava roots and leaves and its relationship to the recommended daily allowance for vitamin A. Total carotenoids, iron and zinc contents in fresh yellow cassava leaves, roots and products (gari, konkonte, boiled cassava roots and leaves), antioxidant activity and the in vitro bioaccessibility of the carotenoids were determined using standard methods. A cross-sectional survey was carried out to identify the consumption patterns of white cassava, the knowledge, and the perception of yellow flesh cassava among Ghanaians. Total carotenoids (T.C), iron (Fe) and zinc (Zn) for fresh roots ranged from 4.73±0.11 to 10.11±0.18 µg/g; 87.35±3.18 to 146.25±1.20 mg/100g; 0.30± 0.01 to1.55±0.07 mg/100g, respectively. T.C, Fe and Zn for fresh leaves ranged from 792.93±0.98 to 2649.20±29.10 µg/g; 118.35±0.070 to 07182.05± mg/100g; 3.75±0.64 to 15.50±0.14 mg/100g respectively. T.C for gari was between 3.21±2.79 and 7.39±1.06 µg/g, iron 118.75±0.64 to 181.85±2.05 mg/100g and zinc, 0.25±0.07 to 0.80±0.14 mg/100g. Iron and zinc contents for the kokonte samples ranged from 101.45±0.64 to 116.30± 0.14 mg/100g and 0.15±0.07 to 0.70±0.01 mg/100g, however, T.C was not detectable. T.C for boiled roots were between 1.22±0.05 and 2.14±0.11µg/g. Iron content for the samples ranged from 118.75±0.64 to 181.85±2.05 mg/100g and for zinc, 0.60±0.01 to 1.30±0.01 mg/100g. T.C for boiled leaves was between 524.39±9.89 and 1323.5±15.6 µg/g, iron; 95.90±0.01 and 148.75±2.76 mg/100g and zinc 0.60±0.01-1.30±0.01mg/100g. In vitro bio-accessibility of carotenoids for boiled roots had the highest of 104.42±0.88%, gari had the highest value of 57.22±9.01%, and boiled leaves 0.28±0.01%. Gari recorded the highest frequency of consumption. 36.6% of the respondents knew yellow flesh cassava. 51.2% were willing to accept yellow flesh cassava. Fermentation, drying, roasting, and boiling retained some carotenoids after processing, but solar drying over a long period completely degraded carotenoids in yellow cassava roots. Cassava leaves had higher retention of carotenoids, but cassava roots had more bio-accessible carotenoids. Carotenoids in yellow flesh cassava leaves had antioxidant properties that have the potential to help combat free radicals in the body. The knowledge and “willingness to accept” yellow cassava was low among Ghanaians. Yellow cassava will serve as a promising source of provitamin A.

Identification and Characterization of Carotenoids, Vitamin E and Minerals of Biofortified Sorghum

Abstract Objectives Sorghum is a critical staple crop in Sub-Saharan Africa and has been included in biofortification efforts to enhance shortfall micronutrient content including provitamin A carotenoids (pVA), zinc and iron. The purpose of this study was to evaluate progress in enhancement of pVA, tocochromanol (vitamin E), iron and zinc content as well as improvements in stability from a new generation of transgenic biofortified sorghum events in order to prioritize selection for translation to food systems. Methods Transgenic sorghum events (n = 16) from three different genotypic backgrounds developed to increase provitamin A biosynthesis (PSY1 + CRTI genes, +/− CRTB gene) and increase tocochromanol accumulation (HGGT gene) for vitamin A stability were characterized for carotenoid and tocochromanol profile using liquid chromatography coupled with diode array detection. Events were compared against their respective null segregants and wild type (WT) sorghum. Mineral content of sorghum lines and those developed to increase iron and zinc accumulation (YSL2 + NAS2 genes) was assessed by inductively coupled plasma - optical emission spectrometry. Storage stability of carotenoids and tocochromanols was assessed under controlled conditions (25°C; 57%RH) over 3 months. Results Total pVA content from transgenic sorghum (5.9 ± 0.1 – 28.6 ± 0.6 mg/gFW) was significantly different (P &amp;lt; 0.05) from null (0.4 ± 0 – 1.2 ± 0 mg/gFW) or WT (0.73 ± 0.2 mg/gFW). A general increase in total tocochromanol accumulation was observed in transgenic sorghum events (14.9 ± 0.8 – 36.2 ± 1.3 mg/gFW) compared to null/WT (14.2 ± 0.5 – 32.4 ± 4.4 mg/gFW) with significant differences observed among transgenic events across different sorghum genotypes (P &amp;lt; 0.05). Mineral accumulation varied among sorghum events with levels ranging from 28.44 ± 1.9 – 48.85 ± 4.9 mg/g and 27.65 ± 4.5 – 63.59 ± 13.4 mg/g FW for zinc and iron respectively. Highest level of zinc and iron was observed in Tx430 sorghum event. Conclusions Findings from this study highlight progress in pVA levels of transgenic biofortified sorghum and the potential for increased vitamin E levels to improve pVA stability over storage. Studies are underway to characterize the bioaccessibility of pVA carotenoids, Fe and Zn from these events. Funding Sources Pioneer Foundation.

Characterization of Processing Influences on In Vitro Bioaccessibility of Carotenoids and Chlorophylls from Six Spinach Genotypes

Abstract Objectives Spinach is a rich source of bioactives including carotenoids and chlorophylls. Ultimate delivery, or bioavailability, of these bioactives to consumers varies depending on pre-/post-harvest factors that impact the food matrix. The interaction between food processing, oral processing (mastication), and spinach genotype have not been explored. Insights into these factors hold the potential to identify interaction effects between genotype and processing (GxP). Methods Six genotypes of spinach selected based on previous bioaccessibility screening were greenhouse grown in Salisbury, NC (Fall 2019), harvested, and stored fresh at 4C (24 hr) or at −80C after processing by blanching (2 min, 100C), thermal sterilization (121C for 15 min), or juicing. All genotypes were subjected to all processing methods, and a portion of each sample was subjected to simulated mastication while another was homogenized (30 sec) into a puree. All samples were subjected to a three-phase in vitro digestion to assess the transfer of carotenoids and chlorophyll derivatives from the food matrix to the aqueous micellar fraction (bioaccessibility). Results Processing method, genotype, and GxP had a significant influence on total bioactive content (P &amp;lt; 0.01), relative bioaccessibility (P &amp;lt; 0.01), and bioaccessible content (P &amp;lt; 0.01). Average bioactive content decreased in the order of juiced (26.2–36.9 μmol/g), blanched (23.3–30.0 μmol/g), thermally sterilized (22.5–27.3 μmol/g), and fresh spinach (18.6–25.0 μmol/g). Bioaccessible content decreased from juiced (6.8–9.8 μmol/g), to fresh (4.0–6.9 μmol/g) and blanched (4.6–5.6 μmol/g), and then thermally sterilized (2.4–3.3 μmol/g). Bioaccessible content from masticated samples was similar for thermally sterilized (0.9–1.5 μmol/g) and fresh samples (0.7–1.3 μmol/g). Conclusions Results indicate that heat treatment preserves bioactives in these six spinach genotypes and may modestly decrease their bioaccessibility. Influence of mastication on bioaccessible content of bioactives supports the notion that oral processing is a critical factor impacting ultimate bioaccessibility from vegetables. Together, these results provide valuable information for optimization of bioactive delivery. Funding Sources Foundation for Food and Agriculture Research.

Effects of pectins and sugars on β-carotene bioaccessibility in an in vitro simulated digestion model

There is lack of information about the effects of pectin and sugars on carotenoid delivery in a simple juice model system. Therefore, the effect of pectin and sugars on β-carotene bioaccessibility (CBA) and the characteristics of digestive fluids in juice model systems were studied. Carotenoid retention ratio (CRR) in the small intestine and the characteristics of digestive fluids, including color parameters and rheological properties, were investigated to gain insight into the mechanism that can alter carotenoid bioaccessibility. Results illustrated that higher pectin concentration, medium methoxyl pectin (MMP), and low methoxyl pectin (LMP) increased the initial apparent viscosity. However, there was no marked difference for the apparent viscosity of all systems in the stomach and small intestine phases. Generally, systems with sugars had higher CRR than those with pectin. Lower pectin concentration increased CBA. Systems with MMP had higher CBA than those containing high methoxyl pectin (HMP) and LMP; therefore, the effects of degree of methoxylation (DM) were not proportional to CBA. Among systems with different sugars, sucrose could achieve the highest CBA (4.59%). A comprehensive investigation of the effects of pectin and sugars on carotenoid delivery during digestion will be a theoretical guidance to improve nutritional qualities of juice products.

High-pressure homogenization as compared to pasteurization as a sustainable approach to obtain mandarin juices with improved bioaccessibility of carotenoids and flavonoids

High-pressure technologies are among those with increased interest in the sustainable production of quality-enhanced food products. In this work, Ortanique mandarin juices have been submitted to traditional pasteurization conditions (time/temperature of 65 °C/15 s, 85 °C/15 s and 92 °C/30 s) and energy-saving high-pressure homogenization (HPH, 150 MPa) treatments to compare the effects on the physicochemical composition and in vitro bioaccessibility of carotenoids and flavonoids. In general, physicochemical attributes of the homogenized sample were similar to those found in fresh juice, with similar ascorbic acid content and cloudiness but with significant colour differences in all cases. The bioaccessibility of total carotenoids was similar in fresh and pasteurized juices in contrast to the HPH sample that exhibited a five-fold increase, which suggests a positive effect of particle size reduction to favour the action of digestive enzymes. A clear increase in the levels of epoxycarotenoids was detected in the micellar fractions of digested HPH juices, although such carotenoids are not detected in human fluids or tissues. Regarding the bioaccessibility of flavonoids, no significant differences were found in the samples studied. Results obtained can help the implementation of HPH processing to obtain natural beverages with enhanced nutritional properties.

Phytosterol vehicles used in a functional product modify carotenoid/cholesterol bioaccessibility and uptake by Caco-2 cells

Abstract Functional foods containing dispersible phytosterols (DPs) are recommended to reduce cholesterol absorption in humans. However, only a few studies have been conducted on the effect of DP vehicles on carotenoid bioaccessibility and uptake by intestinal cells. On a previously developed fermented maize product containing both DPs and carotenoids, we aim to evaluate the effect of DPs encapsulated by maltodextrin on the carotenoid/phytosterol/cholesterol interactions during gastro-duodenal digestion. Thanks to maltodextrin properties, β-carotene and lycopene bioaccessibilities were significantly improved by 40.2 ± 1.4% while that of β-cryptoxanthin decreased by 14 ± 0.1%. Additionally, the presence of DPs reduced the cholesterol micellarization by 51.8 ± 4.2%. Despite a slight decrease in carotenoid uptake caused by the DP vehicle, related to micelle size, an inhibition of cholesterol accumulation by Caco-2 cells was observed. These results highlighted the key role of maltodextrin as a vehicle of DPs on carotenoid and cholesterol absorption.

Development of β‐carotene loaded nanoemulsion using the industrial waste of orange (Citrus reticulate) peel to improve in vitro bioaccessibility of carotenoids and use as natural food colorant

Converting waste to valuable products is increasingly getting attention in recent years. After extraction of juice in many fruits, the peel goes as waste. Herein, we have used orange (Citrus reticulate) peel waste to extract β-carotene. The extracted β-carotene was used to develop a stable nanoemulsion (NE) using a VXX750 ultrasonic homogenizer (Sonics & Materials, USA) to use as a natural colorant in food products. The droplet size and surface charge of developed NE were 143.7 nm and −38.2 mV. The addition of NE to the fruit juice significantly enhances its color, thus providing an alternative to the use of synthetic color. The NE further increases the β-carotene bioaccessibility and also retinol activity equivalent (RAE) in the fruit juice. Analysis of the Citrus reticulata peel extract was done using UV–Vis spectrophotometer and HPLC. The quantity of β-carotene extracted from Citrus reticulata peel was 23.57 μg/gm and total carotenoid content was 27.61 μg/gm. Practical applications Generating value added products from waste is the need of the hr for sustainable development and lowering environmental pollution caused by dumping the food waste. We have developed a β-carotene loaded NE from the waste of orange peel to act as natural food color as well as to increase the bioaccessibility of β-carotene increasing the nutritional value of the juice. After addition of the nanoemulsion, bioaccessibility of β-carotene and retinol activity equivalents (RAE) significantly increased. We have further used it as natural food colorant providing alternative to the synthetic food color.

Evaluation of bioaccessibility of zeaxanthin dipalmitate from the fruits of Lycium barbarum in oil-in-water emulsions

Zeaxanthin dipalmitate (ZD) is the main constituent of carotenoids in the fully ripe fruits of Lycium barbarum. In the present study, the effect of the unsaturation degree of oil on the bioaccessibility of ZD in oil-in-water (O/W) emulsions and the bioaccessibility of ZD in the mixture of L. barbarum fruit (LF) and emulsion (LF-E) were investigated. The coarse O/W emulsions were prepared with 5 wt% oil phase and 95 wt% aqueous phase which containing 1.5 wt% lecithin and 0–0.4 wt% xanthan gum (XG). The viscosity and stability of emulsions increased with the increasing of XG concentration, and the emulsion with 0.4 wt% XG had the largest particle size, whereas XG concentration showed a limited effect on ξ-potential. Furthermore, the bioaccessibility of ZD in different unsaturated degree oil emulsions were investigated by in vitro digestion. The results showed that the particle sizes of O/W emulsions decreased significantly from gastric phase to intestinal phase, whereas the ξ-potential absolute values decreased in gastric phase but increased significantly in intestinal phase. Monounsaturated fatty acid-rich oil emulsions led to higher bioaccessibility compared with polyunsaturated fatty acids-rich oil emulsions, and the olive oil emulsion exhibited the highest bioaccessibility of 25.67%. Finally, the powder of LF (50% w/v) was added to the olive oil emulsion (5 wt% oil content) to investigate the effect of lipid on digestion. The bioaccessibility of ZD in LF-E increased 14.8% than that in LF. The results might facilitate the rational design of emulsions that boost the bioaccessibility of carotenoids in fruits and vegetables.

Characterization and the impact of in vitro simulated digestion on the stability and bioaccessibility of carotenoids and their esters in two Pouteria lucuma varieties

Lucuma is a starchy orange-yellow fruit native to the Andean region. It is widely consumed in Latin America and has been recently adapted to the agronomical characteristics of the south region of Spain. However, its carotenoid profile has never been reported. The aim of this study was to characterize the carotenoid and carotenoid ester composition of lucuma pulps (var. Molina and Beltran) and assess their bioaccessibility with an in vitro simulated gastrointestinal digestion according to the INFOGEST® methodology. The carotenoid profile in lucuma pulps revealed a high qualitative diversity composed of 33 compounds, corresponding to 9 free xanthophylls, 9 hydrocarbon carotenes and 15 xanthophyll esters. (13Z)-violaxanthin, (all-E)-violaxanthin and (all-E)-antheraxanthin were the most abundant carotenoids in lucuma fruits and were naturally present as xanthophyll esters: (all-E)-antheraxanthin 3-O-palmitate, (all-E)-violaxanthin laurate and (all-E)-violaxanthin palmitate. Carotenoids were stable during in vitro digestion; however, their release from the food matrix was limited which contributed to their low bioaccessibility.

Effect of edible plant materials on provitamin A stability and bioaccessibility from extruded whole pearl millet (P. typhoides) composite blends

Blends of cereals and nutrient dense plant materials are increasingly being explored as a strategy for food-to-food fortification in areas of Sub-Saharan Africa, where processing is often applied to enhance product attributes, shelf life and safety. However, little is known regarding the potential impact of these strategies on micronutrient retention and bioaccessibility. In this study whole grain pearl millet (WGM) was blended with carrot powder (source of provitamin A) and Adansonia digitata (Baobab) and Moringa oleifera (Moringa) leaf powders (source of iron) to provide formulations with 25% of the recommended daily allowance (RDA) for Vitamin A. These blends were extruded to produce instant cereal porridges appropriate for consumer markets. Recovery of provitamin A carotenoid ranged from 60.0 to 90.3% after extrusion with higher recoveries in formulations including Moringa and Baobab. Extrusion had a significant negative (p < 0.05) impact on β-carotene bioaccessibility compared to corresponding dry blends (52% versus 47%; P < 0.05). However, the presence of Baobab in the formulation did enhance provitamin A carotenoid bioaccessibility. These results suggest that extruded blends of native plant materials with whole grain millet has potential to deliver products with stable and bioaccessible provitamin A.

Mayonnaise as a model food for improving the bioaccessibility of carotenoids from Bactris gasipaes fruits

Carotenoids from Bactris gasipaes fruits were extracted with an ultrasound-assisted approach using sunflower oil, which was used to develop an oil-in-water (O/W) food emulsion similar to commercial mayonnaise with a lower lipid content. The qualitative carotenoid profile of the O/W emulsion was similar to that of lyophilized fruit. Using an in vitro digestion model adapted from the INFOGEST protocol, the results show that the O/W food emulsion had approximately 11-fold more bioaccessible carotenoids than the lyophilized fruit. In addition, the food model developed in this study had high sensory acceptance in all the evaluated attributes (acceptability scores for colour, aroma, taste, texture and overall acceptance of approximately 8.0 on a 9-point hedonic scale), as well as excellent thermal and gravitational stability (evaluated during 72 days of storage) and antioxidant activity (4.80 α-tocopherol relative). The present work presents a successful alternative for carotenoid incorporation into new foodstuffs, representing an excellent model for the design of functional products with more bioaccessible liposoluble bioactive compounds. This model can be used to add functionality to a food that typically has low nutritional value.