Comprehensive Update on Carotenoid Colorants from Plants and Microalgae: Challenges and Advances from Research Laboratories to Industry.

The substitution of synthetic food dyes with natural colorants continues to be assiduously pursued. The current list of natural carotenoid colorants consists of plant-derived annatto (bixin and norbixin), paprika (capsanthin and capsorubin), saffron (crocin), tomato and gac fruit lycopene, marigold lutein, and red palm oil (α- and β-carotene), along with microalgal β-carotene and astaxanthin and fungal β-carotene and lycopene. Potential microalgal sources are being sought, especially in relation to lutein, for which commercial plant sources are lacking.

Comprehensive review on carotenoid composition: Transformations during processing and storage of foods.

Stimulated by their multifaceted functions and actions, carotenoids have been among the most investigated food components, producing a voluminous, complicated, and sometimes inconsistent literature. This review puts into context developments in the last decade to have a comprehensive current knowledge on these valuable food constituents. Carotenoid analysis continues to show the wide biodiversity of carotenogenic foods and the many factors that affect the composition.

Update on natural food pigments - A mini-review on carotenoids, anthocyanins, and betalains.

Extensive structure elucidation has revealed a remarkable diversity of structures for carotenoids, anthocyanins, and betalains, the major natural pigments in plant-derived foods. Composition, stability, influencing factors, processing effects have been widely investigated. Carotenoids isomerize and oxidize while anthocyanins undergo hydrolysis, nucleophilic attack of water, ring fission, and polymerization during thermal processing.

Structures and Analysis of Carotenoid Molecules.

Modifications of the usual C40 linear and symmetrical carotenoid skeleton give rise to a wide array of structures of carotenes and xanthophylls in plant tissues. These include acyclic, monocyclic and dicyclic carotenoids, along with hydroxy and epoxy xanthophylls and apocarotenoids. Carotenols can be unesterified or esterified (monoester) in one or two (diester) hydroxyl groups with fatty acids.

HPLC-DAD-ESI/MS identification and quantification of phenolic compounds in Ilex paraguariensis beverages and on-line evaluation of individual antioxidant activity.

"Chimarrão" and "tererê" are maté (dried, toasted and milled Ilex paraguariensis leaves and stemlets) beverages widely consumed in South America. This paper describes the application of HPLC-DAD-ESI/MS method for the identification and quantification of caffeoylquinic acids (CQA), flavonol glycosides and purine alkaloids in these beverages. The beverage samples were prepared from commercial lots of maté from Southern Brazil.

Statistical optimisation of cell growth and carotenoid production by rhodotorula mucilaginosa.

Sequential statistical methods were used to maximise carotenoid production by a strain of Rhodotorula mucilaginosa, isolated from the Brazilian ecosystem. Initially, a factorial 2(5-1) experimental design was used, and the variables were pH and the levels of glucose, yeast extract, MgSO4.7H2O and KH2PO4.

Determination of catechins in green tea infusions by reduced flow micellar electrokinetic chromatography.

A sulfated-β-cyclodextrin (s-β-CD) modified reduced flow micellar electrokinetic chromatography (RF-MEKC) method was developed and validated for the determination of catechins in green tea. The optimal electrolyte consisted of 0.2% triethylamine, 50mmol/L SDS and 0.

Behavior of flavonols and carotenoids of minimally processed kale leaves during storage in passive modified atmosphere packaging.

Minimally processed kale leaves were packed in passive modified atmosphere and stored at 3 conditions: 1 °C in the dark and 11 °C with or without light exposure. The products were evaluated during storage in terms of headspace gas composition, sensory attributes, flavonol, and carotenoid contents. The sensory quality decreased slightly during 17 d at 1 °C in the dark.

Lycopene epoxides and apo-lycopenals formed by chemical reactions and autoxidation in model systems and processed foods.

To gain a better understanding of the reactions and the underlying mechanisms of the oxidative degradation of lycopene, the products formed by epoxidation with m-chloroperbenzoic acid (MCPBA), oxidative cleavage with KMnO(4), and autoxidation in low-moisture and aqueous model systems, under light exposure, at ambient temperature were identified. The presence of oxidation products was also verified in processed products (tomato juice, tomato paste, tomato puree, guava juice, "goiabada"). A total of 8 lycopene epoxides and a cyclolycopene diol were formed by the reaction of lycopene with MCPBA and 6 apo-lycopenals were produced with KMnO(4).

Inorganic contaminants in bee pollen from southeastern Brazil.

A set of experiments was carried out to validate a method for inorganic contaminants in honeybee-collected pollen, consisting of digestion of the samples in a closed microwave-assisted system and quantification of 10 inorganic contaminants by ICP OES. Forty-three samples of Brazilian bee pollen, collected in southeastern Brazil during one year, were analyzed. Determination of these analytes is important both as bioindicators of pollution and to verify the safety of consuming the pollen itself.

Multivariant optimization, validation, and application of capillary electrophoresis for simultaneous determination of polyphenols and phenolic acids in Brazilian wines.

A method for the simultaneous determination of the stilbene resveratrol, four phenolic acids (syringic, coumaric, caffeic, and gallic acids), and five flavonoids (catechin, rutin, kaempferol, myricetin, and quercetin) in wine by CE was developed and validated. The CE electrolyte composition and instrumental conditions were optimized using 2(7-3) factorial design and response surface analysis, showing sodium tetraborate, MeOH, and their interaction as the most influential variables. The optimal electrophoretic conditions, minimizing the chromatographic resolution statistic values, consisted of 17 mmol/L sodium tetraborate with 20% methanol as electrolyte, constant voltage of 25 kV, hydrodynamic injection at 50 mbar for 3 s, and temperature of 25 degrees C.

Qualitative and quantitative differences in the carotenoid composition of yellow and red peppers determined by HPLC-DAD-MS.

The carotenoids of a yellow (F(1) Amanda hybrid) and a red (F(1) Magali hybrid) pepper (Capsicum annuum L.) at the ripe stage, marketed in Campinas, Brazil, were identified by the combined use of the chromatographic behavior, absorption spectra, and chemical reactions, confirmed by the mass spectra. HPLC was carried out with a Spherisorb ODS 2 (C18, monomeric, 3 microm, 4.

Degradation of lycopene and beta-carotene in model systems and in lyophilized guava during ambient storage: kinetics, structure, and matrix effects.

Being highly unsaturated, carotenoids are susceptible to isomerization and oxidation during the processing and storage of food. In the present study, the degradation of acyclic lycopene and dicyclic beta-carotene in low-moisture and aqueous model systems, as well as in lyophilized guava, during storage at ambient temperature, in the absence or presence of light, was investigated. Both carotenoids followed first order kinetics under the various conditions investigated.

Variation in the carotenoid composition of the lycopene-rich Brazilian fruit Eugenia uniflora L.

The indigenous pitanga (Eugenia uniflora L.) is now marketed and commercially processed in Brazil. In the present work, the carotenoids of the pitanga fruit from two states and at two stages of ripening, as well as of processed pitanga products (frozen pulp and juice, the brands being designated as A, B and C) commercialized in Campinas, São Paulo, were determined by HPLC.

Processed and prepared corn products as sources of lutein and zeaxanthin: compositional variation in the food chain.

Widely consumed by populations of all socioeconomic classes worldwide, corn is one of the few food sources of lutein and zeaxanthin. However, data on these carotenoids in processed corn and corn as eaten are lacking. Thus, the major carotenoids in the principal brands of processed corn (canned corn, corn meal, corn flour, corn flake) and in typical corn dishes (farofa, boiled corn, pamonha, curau, fried and boiled polenta) were determined.

Qualitative and quantitative differences in carotenoid composition among Cucurbita moschata, Cucurbita maxima, and Cucurbita pepo.

Squashes and pumpkins are important dietary sources of carotenoids worldwide. The carotenoid composition has been determined, but reported data have been highly variable, both qualitatively and quantitatively. In the present work, the carotenoid composition of squashes and pumpkins currently marketed in Campinas, Brazil, were determined by HPLC-DAD, complemented by HPLC-MS for identification.

Aflatoxin M(1) and ochratoxin A in a human milk bank in the city of São Paulo, Brazil.

Because infants are more susceptible to the adverse effects of mycotoxins, this work was carried out to determine aflatoxin M(1) (AFM(1)) and ochratoxin A (OA) in milk from the Human Milk Bank of the Southern Regional Hospital, São Paulo, Brazil. Analytical methods were first established and evaluated. The methods involved the extraction of AFM(1) with methanol and OA with 1% aqueous sodium bicarbonate solution and methanol, clean-up with immunoaffinity columns having antibodies specific for each mycotoxin and quantification by high performance liquid chromatography (HPLC) with fluorescence detection.

Food carotenoids: analysis, composition and alterations during storage and processing of foods.

Substantial progress has been achieved in recent years in refining the analytical methods and evaluating the accuracy of carotenoid data. Although carotenoid analysis is inherently difficult and continues to be error prone, more complete and reliable data are now available. Rather than expressing the analytical results as retinol equivalents, there is a tendency to present the concentrations of individual carotenoids, particularly beta-carotene, beta-cryptoxanthin, alpha-carotene, lycopene, lutein and zeaxanthin, carotenoids found in the human plasma and considered to be important to human health in terms of the provitamin A activity and/or reduction of the risk for developing degenerative diseases.

New data on the total lipid, cholesterol and fatty acid composition of raw and grilled beef longissimus dorsi.

Simultaneous analyses of total lipids, cholesterol and fatty acids were carried out on raw and grilled beef longissimus dorsi trimmed of external fat. Cholesterol was determined by high performance liquid chromatography and the fatty acids by gas chromatography. Mean total lipid (g/100 g) ranged from 2.

Carotenoid composition of hydroponic leafy vegetables.

Because hydroponic production of vegetables is becoming more common, the carotenoid composition of hydroponic leafy vegetables commercialized in Campinas, Brazil, was determined. All samples were collected and analyzed in winter. Lactucaxanthin was quantified for the first time and was found to have concentrations similar to that of neoxanthin in the four types of lettuce analyzed.

Effects of Ripening, Cultivar Differences, and Processing on the Carotenoid Composition of Mango.

The carotenoid composition of mangoes produced in Brazil was determined by HPLC to appraise the effects of some influencing factors. Total carotenoid rose from 12.3 to 38.

Latin American food sources of carotenoids.

Latin America has a wide variety of carotenogenic foods, notable for the diversity and high levels of carotenoids. A part of this natural wealth has been analyzed. Carrot, red palm oil and some cultivars of squash and pumpkin are sources of both beta-carotene and alpha-carotene.

Sources of errors in the quantitative analysis of food carotenoids by HPLC.

Several factors render carotenoid determination inherently difficult. Thus, in spite of advances in analytical instrumentation, discrepancies in quantitative results on carotenoids can be encountered in the international literature. A good part of the errors comes from the pre-chromatographic steps such as: sampling scheme that does not yield samples representative of the food lots under investigation; sample preparation which does not maintain representativity and guarantee homogeneity of the analytical sample; incomplete extraction; physical losses of carotenoids during the various steps, especially during partition or washing and by adsorption to glass walls of containers; isomerization and oxidation of carotenoids during analysis.

Changes in carotenoids during processing and storage of foods.

Being highly unsaturated, carotenoids are susceptible to isomerization and oxidation during processing and storage of foods. Isomerization of trans-carotenoids to cis-carotenoids, promoted by contact with acids, heat treatment and exposure to light, diminishes the color and the vitamin A activity of carotenoids. The major cause of carotenoid loss, however, is enzymatic and non-enzymatic oxidation, which depends on the availability of oxygen and the carotenoid structure.