... Fig. 2. UV-Visible spectra of unknown peaks 9, 11, 12 and 13 from litchi peel extract. A, pea... more ... Fig. 2. UV-Visible spectra of unknown peaks 9, 11, 12 and 13 from litchi peel extract. A, peak 9; b, peak 11; c, peak 12 and d, peak 13. View Within Article. Table 2. Changes in phenolic compounds and anthocyanins in litchi fruit ...
A survey of the food industry in the Yorkshire and Humberside region regarding the implementation... more A survey of the food industry in the Yorkshire and Humberside region regarding the implementation of the Hazard Analysis Critical Control Point (HACCP) system is presented. The objectives were: to establish the level of implementation of HACCP systems, to obtain information of industry’s hazard awareness and to establish the barriers to HACCP implementation. 127 (72.6%) out of food companies had
The objective of this study was to improve Niven's medium (NM) for the op... more The objective of this study was to improve Niven's medium (NM) for the optimized enumeration of histamine-forming bacteria (HFB). The parameters modified related to solidification of the agar at low pH values (pH 5.3 to 5.8), incubation time (24, 48, and 72 h) and temperature (30 and 37 degrees C), number of colonies developed on the plate to allow enumeration of HFB, and color differentiation. Strains of HFB, Morganella morganii, Klebsiella pneumoniae, and Hafnia alvei were examined for their ability to change color on NM. The three microorganisms produced different colors on the medium, which can be used for preliminary identification of HFB. Quantitative analysis of HFB proved to be achievable, with the prerequisite that only 1 to 80 colonies developed on the medium allow effective enumeration. A larger number of colonies results in color development throughout the medium, making the distinction between HFB and other bacteria unachievable. Growth of prolific HFB was noticeably better at pH values from 5.3 to 5.5, compared to 6.3, on NM. Growth at 5.3 and 5.5 on NM also presented a significant advantage in comparison to growth on plate count agar (PCA; pH 7) at the same incubation temperature. The increased agar concentration of 3% was found to give better solidification at pH 5.3 to 6.0, compared to 2%. This agar concentration also allows autoclaving for 12 min at 121 degrees C, overcoming the hydrolysis problems that appear at the lower concentration of 2%. The construction of a color chart for the recognition of the pH change due to histidine decarboxylase activity was also achieved.
Litchi (Litchi chinensis Sonn. cv. Huaizhi) fruit were treated with aqueous solutions of 1.0 or 2... more Litchi (Litchi chinensis Sonn. cv. Huaizhi) fruit were treated with aqueous solutions of 1.0 or 2.0% chitosan coating 1 h after dipping in 0.1% thiabendazole (TBZ), and then stored at 4°C and 90% relative humidity (RH). Changes in browning, anthocyanins, flavonoids, total ...
Four different colored carrots, orange, purple with orange core, yellow, and white, were examined... more Four different colored carrots, orange, purple with orange core, yellow, and white, were examined for their content of phenolics, antioxidant vitamins, and sugars as well as their volatiles and sensory responses. A total of 35 volatiles were identified in all carrots, 27 positively. White carrot contained the highest content of volatiles, followed by orange, purple, and yellow. In total, 11, 16, 10, and 9 phenolic compounds were determined for the first time in orange, purple, yellow, and white carrots, respectively. Of these, chlorogenic acid was the most predominant phenolic compound in all carrot varieties. Differences (p < 0.05) in relative sweetness, the contents of vitamin C and alpha- and beta-carotenes, and certain flavor characteristics were observed among the colored carrot varieties examined. Purple carrots contained 2.2 and 2.3 times more alpha- and beta-carotenes (trace in yellow; not detected in white) than orange carrots, respectively. Purple carrot may be used in place of other carrot varieties to take advantage of its nutraceutical components.
... Fig. 2. UV-Visible spectra of unknown peaks 9, 11, 12 and 13 from litchi peel extract. A, pea... more ... Fig. 2. UV-Visible spectra of unknown peaks 9, 11, 12 and 13 from litchi peel extract. A, peak 9; b, peak 11; c, peak 12 and d, peak 13. View Within Article. Table 2. Changes in phenolic compounds and anthocyanins in litchi fruit ...
A survey of the food industry in the Yorkshire and Humberside region regarding the implementation... more A survey of the food industry in the Yorkshire and Humberside region regarding the implementation of the Hazard Analysis Critical Control Point (HACCP) system is presented. The objectives were: to establish the level of implementation of HACCP systems, to obtain information of industry’s hazard awareness and to establish the barriers to HACCP implementation. 127 (72.6%) out of food companies had
The objective of this study was to improve Niven's medium (NM) for the op... more The objective of this study was to improve Niven's medium (NM) for the optimized enumeration of histamine-forming bacteria (HFB). The parameters modified related to solidification of the agar at low pH values (pH 5.3 to 5.8), incubation time (24, 48, and 72 h) and temperature (30 and 37 degrees C), number of colonies developed on the plate to allow enumeration of HFB, and color differentiation. Strains of HFB, Morganella morganii, Klebsiella pneumoniae, and Hafnia alvei were examined for their ability to change color on NM. The three microorganisms produced different colors on the medium, which can be used for preliminary identification of HFB. Quantitative analysis of HFB proved to be achievable, with the prerequisite that only 1 to 80 colonies developed on the medium allow effective enumeration. A larger number of colonies results in color development throughout the medium, making the distinction between HFB and other bacteria unachievable. Growth of prolific HFB was noticeably better at pH values from 5.3 to 5.5, compared to 6.3, on NM. Growth at 5.3 and 5.5 on NM also presented a significant advantage in comparison to growth on plate count agar (PCA; pH 7) at the same incubation temperature. The increased agar concentration of 3% was found to give better solidification at pH 5.3 to 6.0, compared to 2%. This agar concentration also allows autoclaving for 12 min at 121 degrees C, overcoming the hydrolysis problems that appear at the lower concentration of 2%. The construction of a color chart for the recognition of the pH change due to histidine decarboxylase activity was also achieved.
Litchi (Litchi chinensis Sonn. cv. Huaizhi) fruit were treated with aqueous solutions of 1.0 or 2... more Litchi (Litchi chinensis Sonn. cv. Huaizhi) fruit were treated with aqueous solutions of 1.0 or 2.0% chitosan coating 1 h after dipping in 0.1% thiabendazole (TBZ), and then stored at 4°C and 90% relative humidity (RH). Changes in browning, anthocyanins, flavonoids, total ...
Four different colored carrots, orange, purple with orange core, yellow, and white, were examined... more Four different colored carrots, orange, purple with orange core, yellow, and white, were examined for their content of phenolics, antioxidant vitamins, and sugars as well as their volatiles and sensory responses. A total of 35 volatiles were identified in all carrots, 27 positively. White carrot contained the highest content of volatiles, followed by orange, purple, and yellow. In total, 11, 16, 10, and 9 phenolic compounds were determined for the first time in orange, purple, yellow, and white carrots, respectively. Of these, chlorogenic acid was the most predominant phenolic compound in all carrot varieties. Differences (p < 0.05) in relative sweetness, the contents of vitamin C and alpha- and beta-carotenes, and certain flavor characteristics were observed among the colored carrot varieties examined. Purple carrots contained 2.2 and 2.3 times more alpha- and beta-carotenes (trace in yellow; not detected in white) than orange carrots, respectively. Purple carrot may be used in place of other carrot varieties to take advantage of its nutraceutical components.
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