72 PROCEEDINGS 03’ THE SOCIETY OF PUBLIC ANALYSTS “ POL1 OIL,” A NEW ADULTERANT OF GHEE-INDIAN CLARIFIED BUTTE R-FAT. BY J. H. BARNES, B.Sc., F.I.C., AND ARJAN SINGH, L.Aa. (Read at the Meeting, February 2, 1916.) IN the North-West of India, in that tract of cultivated country extending from Umballs in the South, to Peshawar in the North, a persistent thorny weed is found growing with and alongside the wheat crop.It is known locrtlly by the vernacular names of Po& Polyan, Leh, Kasumbhi, or Karav. It belongs to the natural order Compsita, and is known to botanists as Carthamus oxyacarttha, one of the safflowers. The plant itself resembles safflower (the Carthamus tirtctoriw) in appearance, though, unlike that plant, it does not often exceed 2& feet in height.Its period of growth extends from the beginning of the cold se&son to the early dry hot weather- December to May-exactly similar to that of wheat, though the actual breaking of the seed capsules naturally takes place a little later than the reaping of wheat in this part of the world (middle of April till the middle of May), and the germinationt c POLI OIL "-INDIAN CLARIFIED BUTTER-FAT 73 of the seed is about a month later than that of wheat.The plant is troublesome in the reaping and threshing of the cereal crop, and, on account of its growing period coinciding so closely with this, it is very difficult to eradicate. With the great extension of wheat lands in North-West India during the last twenty years through irrigation, this weed has been brought more and more to the notice of the agricul- tural classes, and the Government Department of Agriculture is even now devising means of checking and controlling its extension. I t is not, however, with the plant as a pest to the farmer that we are concerned in this note, but with the industrial uses to which it may be and is put.The seed is edible, for in famine years its use as a food has been recorded by many observers.On expression, it yields a yellow oil which in the Peshawar district is used &S an illuminant, and in other parts of the Punjab is added to Ghee --Indian clarified butter-fat-thus constituting an adulterant of this very important item of Indian food. Bellew (Stewart's (' Punjab Plants," p. 123) states that the oil has been used medioinally, but little is known of this.We have had inquiries from the Indian Museum, Calcutta, for this oil for use in colour stencilling on fabrics. The principal outlet for Poli oil in the Punjab at present seems to be its use as a food, and its colour and taste render it a very suitable and cheap substance with which to adulterate Indian clarified butter-fat. The chemical and physical constants of a genuine sample of fresh oil as deter- mined by us are given below : Specific gravity Iodine value Saponification v Acetyl value (at 15.5" C.) ...... ... ... palue ... ... ... ... ... Acidvalue ... ... ... Reichert-Meissl value ... ... Optical rotation in 200 mm. tube Refractive index at 28" C. ... 9 9 ,, at 40" C. ... ... ... ... 0 . . ... 0.9272 .... . 167-4 ... ... 174.2 ... ... 60.5 ... ... 5.9 ... ... 0.61 ... ... Nil ... ... 1-4818 ... ... 1.4755 I t will be seen that these constants do not bear out those given by Crossley and Le Sueur (J. SOC. Chem. I d . , 1898, 17, 991) for a sample of oil from the Punjab Carthamus oxyacantha. This is probably due to the sample examined by these authors not being fresh. It is well known that all the safflower oils are drying oils, and contain considerable quantities of unsaturated acids, hence their tendency to undergo polymerisation. But whether he has to deal with fresh or stale oil the analyst will have little difficulty in recognising this adulterant when found in con- junction with Ghee. Cf. Bolton and Revis (ANALYST, 1910,35, 343 ; 1911,36,392.) PUNJAR AURICULTURAL COLLEGE.