Pure b-carotene was encapsulated in 25 Dextrose Equivalent maltodextrin by three drying processes (spray, freeze and drum). Stability was studied at 11% and 32% RH and 25°C, 35°C and 45°C. No significant influence of %RH was observed on the retention of b-carotene. Oxidation followed first order kinetics with an initial fast first order reaction followed by a second much slower first order reaction period. Although drum-drying caused more initial loss in drying, the lower surface carotenoids and larger particle size resulted in greater stability as compared to the other methods. The chromametric measurements of "L" and "a" corresponded to the other kinetics and indicated that the first period rapid loss corresponded to the oxidation of surface carotenoids.

No abstract

No abstract

Industrial shrimp waste is a good source of protein, chitin, and carotenoids. In general, this waste is discarded with no attempt to use it, thus contributing to environmental pollution. This study was aimed at recovering the 3 main components of industrial shrimp waste, protein, chitin, and astaxanthin, using enzymatic treatment with Alcalase and pancreatin. An increase in the degree of hydrolysis (DH) from 6% to 12% resulted in 26% to 28% protein recovery. Alcalase was more efficient than pancreatin, increasing the recovery of protein from 57.5% to 64.6% and of astaxanthin from 4.7 to 5.7 mg astaxanthin/100 g of dry waste, at a DH of 12%. The enzymatic hydrolysis of the industrial waste from Xiphopenaeus kroyeri shrimp using Alcalase allowed for 65% protein recovery in the form of hydrolysates, in addition to providing suitable conditions for the recovery of astaxanthin and chitin.

Beta-carotene acts as a pro-vitamin A or anti-cancer compound. Carrots contain the highest amount of beta-carotene of common fruits and vegetables, but each year 25% of carrot production is lost in the U.S. during processing and storage, while, at the same time, the market demand increases. This article is a review of the most recent studies concerning beta-carotene retention in carrots during processing and storage. Reducing the water activity by adding some aw lowering ingredients results in poor shelf-life. Drying or freezing gives better retention during storage than reducing the water activity, if the process is well controlled. Canning or freeze-drying were shown to be more effective. The trans form of beta-carotene in carrots is replaced by the cis form during processing. Beta-Carotene can be extracted from carrots, but the half-life of free beta-carotene is reduced to 2 d in the juice extract at room temperature. By encapsulation methods,the half-life can be increased by 6 months.

No abstract

In this study, the hydrolysis of a flaxseed protein isolate with Alcalase ® was performed as a strategy to generate antioxidant peptides. A chromatographic separation of the hydrolysate was conducted by RP-HPLC. Both hydrolysate and six collected fractions were subjected to ORAC and FRAP assays to evaluate their antioxidant capacity. The higher antioxidant values were shown by fractions containing predominantly low molecular weight peptides, as it was demonstrated by MALDI analysis. Four peptides were identified by LC-MS/MS and one by Edman degradation. The peptide with sequence GFPGRLDHWCASE was synthesised showing a notable ORAC activity, 3.20 µmol Trolox equivalents/µmol of peptide. This value was higher than that reported for butylated hydroxyanisole. Therefore, the contribution of this peptide to the activity of the fraction where it had been found was 61%. The identified sequences represent an advance in the molecular characterization of the flaxseed protein fraction.

The aim of this work was to encapsulate a casein hydrolysate by spray drying using maltodextrins (DE 10 and 20) as wall materials and to evaluate the efficiency of the microencapsulation in attenuating the bitter taste of the hydrolysate using protein bars as the model system. Microcapsules were evaluated for morphology (SEM), particle size, hygroscopicity, solubility, thermal behavior (DSC), and bitter taste with a trained sensory panel by a paired comparison test (nonencapsulated samples vs. encapsulated samples). Bars were prepared with the addition of 3% casein hydrolysate at free or both encapsulated forms, and were then evaluated for their moisture, water activity (aw) and for their bitter taste by a ranking test. Microcapsules were of the matrix type, having continuous surfaces with no apparent porosity for both coatings. Both encapsulated casein hydrolysates had similar hygroscopicity, and lower values than free encapsulated hydrolysates. The degree of hydrolysis of the maltodextrin influenced only the particle size and Tg. The sensory panel considered the protein bars produced with both encapsulated materials less bitter (p < 0.05) than those produced with the free casein hydrolysates. Microencapsulation by spray drying with maltodextrin DE 10 and 20 was successful to attenuate the bitter taste and the hygroscopicity of casein hydrolysates.