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Pigment Stability (pigment + stability)
Selected AbstractsStability of vacuolar betaxanthin pigments in juices from Moroccan yellow Opuntia ficus indica fruitsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2008Hasna El Gharras Summary Pigment stability of yellow juices prepared from Moroccan cactus pear (Opuntia ficus indica) was determined as a function of temperature and pH. The experiments were carried out at temperatures ranging from 80 to 100 °C with juices at pH 3.5, 5 and 6.5. The degree of pigment retention decreased when the temperature increased. The degradation constant rates were determined for thermal degradation rates of pseudo-first order. The Arrhenius plot obtained for the degradation of betaxanthin from the yellow fruits was not linear. Regardless of the temperature treatment, the lowest degradation was obtained for pH 5. Where some stabilizers were tested for the protection of pigments, the results showed that ascorbic acid was a better protective agent at pH 3.5, increasing the protection by 40%. [source] Stability of , -carotene in spray dried preparation of Rhodotorula glutinis mutant 32JOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2003P. Bhosale Abstract Aims: To obtain , -carotene-rich dry cell preparation from mutant 32 of Rhodotorula glutinis and determination of its pigment stability. Methods and Results: The mutant 32 of R. glutinis was grown in a 14 l stirred tank fermenter. Cell mass was concentrated 10-fold by cross-flow microfiltration and then spray dried. Butylated hydroxy toluene (BHT) and d -tocopherol were used as protecting agents. A two-level, three-variable, factorial optimization was performed to achieve moisture-free, non-viable and , -carotene-rich feed additive. Conclusions: The , -carotene and cell mass in stirred tank fermenter were found to be 54 ± 5 mg l,1 and 12·8 ± 2 g l,1, respectively. In the presence of BHT, 97 ± 3% (w/w) , -carotene was recovered for all the inlet temperatures studied. The best , -carotene and yeast powder recoveries were obtained at 160°C, 11·6% (w/v) cell mass concentration and 1 g l,1 BHT. The pigments inside dried yeast powder were stable in dark and cold condition for at least 10 weeks. The purified , -carotene got almost totally denatured, under similar conditions of storage, within 76 h. Significance and Impact of the Study: Spray dried and stable preparation of , -carotene-rich yeast, R. glutinis can provide alternative source of , -carotene for use in animal nutrition. [source] STORAGE STABILITY OF STRAWBERRY JAM COLOR ENHANCED WITH BLACK CARROT JUICE CONCENTRATEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2007EGÜL KIRCA ABSTRACT Black carrot juice concentrate was added to enhance the color of strawberry jams prepared from two locally grown cultivars, Osmanl, and Kara. Compared to other cultivars processed to jams, these two cultivars are lightly colored but very aromatic. Color and pigment stability of colored and noncolored (control) strawberry jams were studied during storage. The use of black carrot concentrate as a source of natural colorant stabilized the color of strawberry jam. The stabilization was more noticeable for jams prepared from Osmanl, cultivar. Monomeric anthocyanin degradation was fitted to a first-order reaction model. Storage temperature had a strong influence on anthocyanin degradation. As the storage temperature increased, the stability of anthocyanins decreased significantly in both colored and noncolored jams. Parallel to decrease in monomeric anthocyanins, hue (h°) values of all jam samples increased throughout the storage. However, increase in h° values was much smaller in colored samples than in noncolored samples. High correlation was found between h° value and anthocyanin concentration at 22C (r = 0.910,0.978) and 37C (r = 0.931,0.981). [source] Production and Properties of Spray-dried Amaranthus Betacyanin PigmentsJOURNAL OF FOOD SCIENCE, Issue 7 2000Y.Z. Cai ABSTRACT: Amaranthus betacyanin extracts were spray-dried using a range of maltodextrins [10-25 dextrose equivalent (DE)] and starches (native/modified) as carrier and coating agents at 5 inlet/outlet air temperatures and 4 feed solid contents. Higher inlet/outlet air temperatures caused greater betacyanin loss during spray drying, and affected slightly the pigment stability during storage. Adding maltodextrins and starches significantly reduced the hygroscopicity of the betacyanin extracts and enhanced storage stability. The 25 DE/10 DE mixed powders provided a longer predicted half-life (63.6 wk) compared to the 25 DE and the 10 DE powders separately. The best dried pigment-containing powder made was superior to commercial red beet powder in physical properties. [source] | ||||||||||