Detection of Enocyanin in Cranberry Juice Cocktail by HPLC Anthocyanin Profile

Adulteration of cranberry juice products by enocyanin, a colorant from grapes, was detected by comparing HPLC chromatographic profiles of cranberry anthocyanins with those from enocyanin. Two peaks present in all enocyanin samples but not in cranberries were identified as delphinidin-3-glucoside and petunidin-3-glucoside. A group of unidentified pigments which eluted after the cranberry pigments was also present in enocyanin. It was possible by considering differences in the chromatograms to detect replacement of 5% or more of the expected amount of cranberry juice in cranberry juice cocktail by a solution of enocyanin. A CG-50 column was used to concentrate the pigments followed by chromatography on a polymer styrene column at pH 1.6. The method gives reliable results even on samples 18 months of age.     

Alaska Pollock (Theragra chalcogramma) Mince and Surimi as Partial Meat Substitutes in Frankfurters: N-Nitrosodimethylamine Formation

Studies were conducted to determine the feasibility of using 3 forms of Alaska pollock (AP) as a partial substitute for meat in a nitrite-cured product. The effect of several pre- and post-processing storage conditions on N-nitrosodimethylamine (NDMA) were studied in frankfurters substituted with 15 and 50% unwashed and washed mince and surimi. In franks made with unwashed mince, frozen stored prior to processing, NDMA increased during frozen storage; little change was observed in franks containing washed mince and surimi. Refrigerated storage of franks generally showed a decrease in NDMA with all 3 forms of fish. Overall, the use of washed mince and surimi at the 15% substitution level gave mean values less than 2 ppb NDMA, even after boiling. The results indicate that 50% unwashed AP mince should not be used as a partial substitute for meat in frankfurters.     

The application of optical fibres as witness devices for the detection of plastic strain and cracking

Low cost optical fibres have recently become readily available for telecommunications purposes. Silica fibres are characterised by high elastic strains to failure. The feasibility of using these fibres for structural integrity monitoring particularly for offshore structures is investigated. The basis of the technique is that a fibre may be bonded to a critical part of a structure and provides an optical path which will be broken if the fibre fails due to plastic strain or crack opening in the critical area.
Groups of fibres which have been given predetermined fracture strains by surface etching were encapsulated in special packs. These packs were bonded to steel and concrete tensile specimens. Strain transfer occurred successfully between the specimens and individual fibres. The distribution of strain to fibre fracture appeared to be uniform along the fibre. The use of several fibres with a range of fracture strains caused fibres to break progressively with increasing strain. For applications to offshore structures it has been found possible to use water-repellent adhesives which can be applied and cured in sea water and suffer no deterioration.
The advantages of this system include versatility, relatively low cost, adaptability to continuous monitoring and the possibility of being fitted retrospectively and refitted after repair operations.     

N-Nitrosothiazolidine and its 4-Carboxylic Acid in Frankfurters Containing Alaska Pollock

In marine fish of the gadoid family trimethylamine oxide can decompose to formaldehyde. It can then react with cysteine and cysteamine, that may in turn react with nitrite, if present, to form N-nitrosothia-zolidine-4-carboxylic acid (NTHZC) and N-nitrosothiazolidine (NTHZ). The NTHZC and NTHZ content of Alaska pollock surimi-meat frankfurters were similar to or lower than those found in an all-meat control, even at 50% substitution. No correlation was found between age of the fish protein prior to processing into surimi meat frankfurters and any measured variables.     

MODELING THE TEMPERATURE EFFECT ON THE FLOW BEHAVIOR OF SWEET POTATO PUREE1

A study was conducted to investigate the effect of temperature on viscosity of sweet potato (SP) puree. Rheological data of the puree were measured using a Bohlin VOR Rheometer. Shear rates employed ranged from 0.01–921 s^?1. Thermal scans were run at 15, 25, 40, 60, 75, and 90C. The puree exhibited “shear thinning” behavior with a yield stress value of 10 Pa at each temperature tested. The characteristic of the flow behavior of the puree was determined by fitting the experimental data to Herschel-Bulkley, Casson and Modified Casson models. The model with the best fit was then used to represent the combined effect of shear rate and temperature on the apparent viscosity of SP puree in a model based upon the Modified Casson model. The model was validated using data for SP puree samples at 50C. Results showed that, within the experimental conditions used in this study, the model could adequately predict apparent viscosities of sweet potato puree processed at different temperatures.     

CONSUMER ACCEPTABILITY OF PROCESSED OSTRICH MEAT PRODUCTS

Two value-added ostrich meat product prototypes were prepared and evaluated by a consumer panel (n = 132) against similar products manufactured entirely from pork. Ostrich "ham" and a control pork ham product were prepared by a traditional ham cure, and Polish sausage products were formulated with either all-pork or a 67% ostrich/33 % pork blend and processed with a commercial spice blend. Ostrich "ham" tended to be rated lower (P = 0.0537) in salt intensity, but had higher flavor intensity ratings. Consumers gave pork ham more favorable ratings for overall acceptability (P< 0.01) and flavor acceptability (P< 0.05). For Polish sausage products, overall acceptability, flavor acceptability, flavor intensity, salt intensity, texture and tenderness were not different (P > 0.05) between all-pork and ostrich/pork varieties. Results indicate that value-added ostrich meat products were more acceptable when they were more finely ground, spiced, and combined with pork in a sausage product than when they were prepared as a "ham" product.     

Comparison of Pond-Raised and Wild Red Drum (Sciaenopsocellatus) with Respect to Proximate Composition, Fatty Acid Profiles, and Sensory Evaluations

The proximate composition, fatty acid profiles, and the sensory characteristics of pond-raised red drum were compared to wild red drum. The proximate compositions and sensory characteristics were similar for pond-raised and wild red drum. The major difference between samples was in the fatty acid profiles. The pond-raised red drum had higher linoleic acid and lower docosahexaenoic acid concentrations than the wild fish samples. The eicosapentaenoic acid concentrations were similar in both pond-raised and wild red drum.     

纤维键接复合材料的超声检测和力学性能测试

纤维键接复合材料，特别是带有转向纤维的复合材料比普通层压板具有更加复杂的内部结构。介绍用超声波对键接复合材料层间界面进行成像，以期建立一种评价键接复合材料产品质量的方法。同时进行了短梁剪切试验，研究材料的破坏行为和缺陷对材料力学性能的影响。