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To measure the color grade of your honey Often used for commercial classificaton of honey With this apparatus you compare a sample of your honey with a color scale to determine the color quality of your honey Historical Devolop
To measure the color grade of your honey. Often used for commercial classificaton of honey. With this apparatus you compare a sample of your honey with a color scale to determine the color quality of your honey.
Historical Devolopment
The colour of commercial honeys, which ranges from pale yellow through amber to deep red or even black, is an important factor in the marketing of honey. In recognition of this fact, an official method for colour grading of honey was developed using Pfund values in millimetres. The original Instrument used to determine Pfund values was the Pfund wedge comparator with a wedge of amber glass, a wedge-shaped cell for holding the honey sample and a millimetre scale with a pointer to indicate the wedge positions where a colour match is obtained.
In 1927 the US Department of Agriculture established its own colour classification for extracted honey based on Pfund values as shown in Table 1.
Water White
0 - 8
Extra White
8,1 - 16,5
White
16,6 - 34
Extra Light Amber
34,1 - 50
Light Amber
50,1 - 85
Amber
85,1 - 114
Dark
more than 114
Visual Honey Grading by Lovibond Glass Colour Standards
To provide a more convenient end economical method of official classification, the Pfund wedge comparator has been largely discarded in favour of instruments such as the Lovibond Comparator 2000+. Here, a sample of honey in an optical glass cell of fixed path length is compared with coloured glass standards representing a suitable range of Pfund equivalent values until a colour match is obtained. Set honey will need to be cleared by gentle warming and left to stand for any bubbles to dissipate before colour grading.
There have been generated conversion figures for Pfund values into colour standards and customised discs for honey classification covering any required range of Pfund values are available. Special requirements often result from differences in various geographical markets; for instance, Italian acacia honey is a very light honey so an appropriate honey grading disc will include a greater selection of Pfund values at the low end of the range.
The Lovibond range also includes standard honey grading discs. For the American market a USDA licensed disc which is graded water white, extra white, white extra light ember, light amber and amber and uses a 33 min optical cell for comparison.
Examples of Lovibond Discs for Honey Grading
Disc
Range
Order Code
4/55Int. Scale
8, 17, 34, 48, 83, 114 mm (Pfund equivalents)
24 55 00
Various ranges
5-45mm (Pfund equivalents in steps of 5)45-85 mm (Pfund equivalents in steps of 5) 85-100 mm (Pfund equivalents in steps of 5) 20-60 mm (Pfund equivalents in steps of 5) 65-105mm (Pfund equivalents in steps of 5)
29 95 7029 95 8029 95 9029 89 3029 89 40
USDA Scale
water white, extra white, white extra light ember, light amber and amber
29 82 80**uses 33mm cell!
Canadian Honey
8, 13, 30, 50, 85, 114 mm (Pfund equivalents)
29 77 80
Pfund Color Grader
The Pfund Color Grader is designed for measuring the colors of Honey, Syrups, Brown Sugar Solutions, Vinegar, Varnishes, Oils and other liquids with similar amber color characteristics.
The Liquid under test is placed in the trough, provided for this purpose. The trough is then placed in the brackets of the inner metal slide. The thin end of the trough should be above the thick end of the wedge.
By means of a rack and gear arrangement the slide is moved past the narrow slit in the !rousing Until 'a color match is obtained at the point where the color density of the liquid matches the color density of the amber wedge. The reading is then made on the millimerer scale which is also calibrated in special divisions to indicate standard color grades for honey.
The illuminating device, furnished as optional equipment, consists of a lamp um with cord and socket; which attaches to the instrument upright and should be used with a 200W. full-frosted bulb. The light from the bulb passes through a daylight filter (optional equipment) and a diffusion glass (standard equipment) to give uniform light intensity over the entire visible range of the trough and wedge.
A new scale which has the individual calibration for each instrument engraved directly thereon, eliminates the necessity for the cumbersome and easily misplaced correction chart formerly used.
An optical eyepiece can be supplied, as optional equipment, which brings the color fields together so that the ease of reading is greatly increased. This eyepiece can he attached to all existing instruments.
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