Effect of Dietary Carotenoids on Reproducers of Amazon River Prawn Macrobrachium amazonicum. Part 2: External Coloration, Accumulation of Astaxanthin in Body Tissues and Pigment Stability in Feed

The color is an important factor to distinguish the commercialized Amazon river prawns. The accumulation of pigments in the body can vary according to the prawn’s diet. In this work, ethanolic extracts of “buriti” and annatto rich in pigments were obtained and tested comparatively with synthetic astaxanthin in the feeding of adults of Macrobrachium amazonicum, together with a control group without pigments and a newly captured wild group. Levels of body pigments were measured using UV reflective spectroscopy and external staining by colorimetry. Differences were observed in the accumulation of astaxanthin in body tissues, differences in saturation between genders and that annatto extract has greater stability in the feed after water immersion (P˂0.05). Further studies are recommended to verify the ideal dosage of natural pigments in relation to synthetic astaxanthin that benefits the productive development of prawns.

Stability of Chlorophyll a Monomer Incorporated into Cremophor EL Nano-Micelles under Dark and Moderate Light Conditions

In this paper, stability of chlorophyll a monomers encapsulated into the Cremophor EL nano-micelles was studied under dark and moderate light conditions, typical of a room with natural or artificial lighting, in the presence of oxygen. The pigment stability against visible light was determined using the dynamic light scattering and molecular spectroscopy (UV-Vis absorption and stationary fluorescence) methods. Chlorophyll a, at the molar concentration of 10−5 M, was dissolved in the 5 wt% Cremophor emulsion for comparison in the ethanolic solution. The stability of such a self-assembly pigment–detergent nano-system is important in the light of its application on the commercial-scale. The presented results indicate the high stability of the pigment monomeric molecular organization in the nano-emulsion. During the storage in the dark, the half-lifetime was calculated as about 7 months. Additionally, based on the shape of absorption and fluorescence emission spectra, chlorophyll aggregation in the Cremophor EL aqueous solution along with the time was excluded. Moreover, the average size of detergent micelles as chlorophyll carriers was not affected after 70 days of the nano-system storage. Pigment stability against the moderate white light (0.1 mW) did not differ significantly from storage conditions in the dark. The photooxidation products, detected by occurrence of new absorption and fluorescence emission bands, was estimated on the negligible level. The stability of such a self-assembly pigment–detergent nano-system would potentially broaden the field of chlorophyll a (chl a) application in the food industry, medicine or artificial photosynthesis models.

Copigmentation with Chlorogenic and Ferulic Acid Affected Color and Anthocyanin Stability in Model Beverages Colored with Sambucus peruviana, Sambucus nigra, and Daucus carota during Storage

The food industry is looking for alternatives to synthetic colorants. Anthocyanins (ACNs) are suitable replacements due to their color characteristics and potential health benefits. The application of sauco (Sambucus peruviana, SP) as a potential source of ACN-based colorants was evaluated and compared to elderberry (Sambucus nigra, SN) and an extract from purple carrots (PC). Color and pigment stability were evaluated using a model beverage system during eight weeks of storage. Copigmentation with chlorogenic acid (CGA) and ferulic acid (FA) were also evaluated. SP ACNs provided darker and more intense colors than those obtained with SN but less intense than those obtained with PC. Addition of CGA and FA resulted in significantly darker colors with higher chroma in beverages colored with SP and SN but not in beverages colored with PC. Copigmentation with FA reduced monomeric pigment half-lives for all ACN sources but increased the chroma half-lives of beverages colored with SP and SN, from 23 to 49 weeks, and from 23 to 55 weeks, respectively. Analyses using liquid chromatography coupled to photodiode array detection and mass spectrometry showed that interaction between non-acylated ACNs and FA resulted in the formation of pyranoanthocyanins. Overall, ACNs from non-acylated sources such as SP, in combination with FA, showed potential for commercial food applications.

Influence of Different Sweeteners on the Stability of Anthocyanins from Cornelian Cherry Juice

Cornelian cherries are red fruits which can be considered as a valuable dietary source of antioxidant biologically active compounds, especially anthocyanins. The purpose of the present study was to investigate the anthocyanins degradation process in Cornelian cherry juice supplemented with different sweeteners. Four formulations of Cornelian cherry juice were prepared using different sugars (sucrose, fructose) or artificial sweeteners (aspartame and acesulfame potassium). The obtained juices were stored at three distinct temperatures (2 °C, 25 °C, and 75 °C) in order to evaluate the effects of the sweetener and storage conditions on the pigment stability. The rate constants (k) and the half time values (t1/2) of the degradation processes were determined. The highest stability was observed for the anthocyanins from the unsweetened juice stored at 2 °C (k = 0.5·10−3 h−1), while the most accelerated degradation was registered for the fructose sweetened juice stored at 75 °C (k = 91.65·10−3 h−1). The presence of the different sweeteners in the Cornelian cherry juice affects their pigment stability during storage. The highest change in the retention of anthocyanins was determined by the presence of fructose, while acesulfame potassium had the less deleterious effect.

Stabilization of Food Colourant and Antimicrobial Activity in Fruit Extracts of Basella rubra. L

Betalains have potential as the natural colourant and functional food with pharmaceutical purposes in food applications. The total betalain content of Basella rubra L. grown at Kalaburagi region is evaluated for the first time. The present study is carried out to determine the pigment stability and antimicrobial activity of fruits of Basella rubra. Total betalain content of fruits was evaluated and it was found to contain a high amount of 48.15 mg betacyanins and sparing amount of 2.53 mg betaxanthins and total betalains account for 50.69mg/100g of fresh fruit pulp. The influence of different additives on the colour stability of pigment was evaluated. More than 80% pigment colour is stable in the presence of 5% sucrose at 4 °C under dark condition. The betalain extract of Basella rubra L fruits showed significant antimicrobial activity against S.typhi, Aspergillus flavus, Microphomia fungi and Rhizopus stolonifer. It is for the first time that the total betalain content and anti-microbial activity of Basella rubra cultivar grown in Hyderabad Karnataka region of Karnataka, India is reported.