Statistical Evaluation of Data for Detecting Adulteration of California Navel Orange Juice

Compositional data from California early-, mid-, and late-season navel orange juice, concentrate and two-stage pulpwash were analyzed by various statistical techniques (ratios, regression, chi-square, Linear combination, and discriminant analysis) for detecting adulteration. These techniques were evaluated according to applicability for detecting three types of adulteration: (1) addition of sugar and/or citric acid, (2) addition of excess or unauthorized pulpwash, and (3) addition of other constituents intended to mask the dilution. Most parameters were significantly affected by time of harvest following commercial maturity. Two-stage pulpwash showed small but significant differences from corresponding single strength juice. Product differences were of about the same magnitude as the differences due to harvest date.     

Prediction and Measurement of the Water Activity of Selected Saturated Salt Solutions at 5°C and 10°C

A theoretical approach, based on the thermodynamic properties of strong electrolyte aqueous solutions, was used to calculate the a_w at 5°C and 10°C of selected saturated salt solutions frequently used as standards in the range of microbial growth. The results agreed very well with experimental measurements at both temperatures for most salts studied, which included NaBr, NaCl, SrC1₂, (NH₄)₂SO₄, KCl, BaCl₂, and K₂SO₄. For KNO₃ the agreement was somewhat less satisfactory and the reasons are discussed.     

Discrepancies of the Davis Method in Estimating Hesperidin Content in Orange Juice

The Davis method for estimating hesperidin in orange juice was shown to give results which were highly dependent upon reaction time, wavelength and sample preparation methods. The indicated hesperidin values obtained by the published method (5 min reaction time) were 10% higher than after 10 min with a corresponding standard curve. Hesperidin values were lower when the absorbance was measured at 360 nm (maximum for hesperidin chalcone) than at 420 nm (Davis procedure). All samples treatments to reduce pulp content tended to lower the results as compared with whole juice. The effects were greater when the absorbance was measured at 360 nm than 420 nm.     

先进的LED驱动器提升全彩视频显示屏的质量

本文介绍了全彩LED视频显示屏的结构以及对LED驱动器的要求,详细介绍了意法半导体为全彩视频显示屏定制的LED驱动器解决方案。     

Characteristics of California Navel Orange Juice and Pulpwasn

California navel orange juice, two-stage pulpwash and concentrated orange juice obtained from a commercial processing plant during the 1979–80 processing season were analyzed by chemical, physical and microbiological methods. Statistically significant differences (P < 0.01) were found between single-strength orange juice and pulpwash in the concentration of nitrate, sulfate, phenolics, carbohydrates, protein, pectin, UV/VIS absorption characteristics, minerals and carotenes. Seasonal variations were found in carbohydrates, organic acids, minerals, microbiological data, UV/VIS absorption characteristics, carotenoids, protein and phenolics. This report outlines methods of analysis, summarizes analytical results and discusses application of these findings to the detection of pulpwash adulteration of orange juice.     

EFFECT OF FROZEN STORAGE ON THE FUNCTIONAL PROPERTY OF RIBBON FISH (TRICHIURUS SAVALA) CUVIER

The ribbon fish (Trichiurus savala) is an important marine fish caught along the coast of Orissa, India amounting to 9.2% of total marine fish catch. The possibility of using frozen ribbon fish to make surimi was investigated. At 1 month interval, fish were thawed under controlled conditions and gels were then made from minces of the flesh. Both puncture and torsion tests showed that the quality of gels declined by 30% after 30 days of storage and thereafter nonsignificant reduction up to 100 days storage of frozen ribbon fish at − 20C. This decline was correlated by a decrease in pH and an increase in formaldehyde concentration in the frozen flesh. The data suggest that a land-based surimi plant could not be operated outside the harvesting season to any appreciable extent using frozen ribbon fish stored at − 20C.

PRACTICAL APPLICATIONS

Ribbon fish ( Trichiurus savala ) is a commercially important fish and is caught all over the state of Orissa, India. Because this fish gets spoiled fast, idea was generated in using frozen fish to produce surimi, which would increase production flexibility and thus allow a land-based surimi plant outside the harvesting season. The result of the present experiment shows that thestorage of headed and gutted ribbon fish at −20C resulted in a significant loss of gel-forming properties of the flesh with time and this loss would be too fast to allow use of storage ribbon fish for making surimi over an extended period in a commercial operation. Possibly, storage at lower temperature than used in the present study is necessary to maintain gel-forming ability and the advantage so obtained would have to be balanced against the increased capital and operational costs of storage at these lower temperatures.