THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL 



YOL. II. 



New York, Septembee, 1881. 



No. 9. 



The Detection of Adulteration 

 in Food. 



BY C. M. VORCE, F.R.M.S. 



IV. — Pepper. 



Next after salt, probably pepper is 

 the most commonly used of the con- 

 diments, usually in the shape of black 

 pepper which is the same as white 

 pepper, " only more of it," and there- 

 fore the black pepper will be first 

 considered. 



To determine of what the genuine 

 pepper berry is composed, and what 

 should be found in genuine ground 

 black pepper, we scrape or rasp into 

 fine powder a dried pepper berry and 

 examine the fragments in turpentine 

 with a i-inch objective. The scrap- 

 ings from the outer part are found to 

 be composed of reddish or brown 

 angular cells, irregularly arranged in 

 two or three layers, with a darker 

 central portion, as seen in Plate II, 

 Fig. I, and many scales of clear, col- 

 orless, glass-like plates are seen 

 (Fig. 2), which are fragments of the 

 outer cuticle. Soaking the fragments 

 (Fig. i) of the outer coat in solution 

 of potash, renders them clearer and 

 of a reddish color, although they still 

 retain a darker, granular, central 

 portion, now shrunken to very small 

 dimensions (Fig. 4), but not entirely 

 disappearing, even after long action 

 of the potash with heat. Within this 

 outer skin of the berry is found a 

 thick layer of pulp-cells, polygonal 

 by pressure, in rows, with numerous 

 larger, dark, round or oblong cells 

 interspersed (Fig. 5). These cells 

 much resemble air-bubbles, but are 

 also found free (Fig. 6 a), and by a 



^-inch objective are found to be 

 thick-walled cells containing disks of 

 oil of a faint greenish yellow color 

 (Fig. 6 d), and drops of this oil, which 

 is undoubtedly the essential oil of the 

 pepper, are found free among the 

 pulp-cells, where it has exuded from 

 the torn oil-cells, when fragments of 

 the pulp are examined in water. After 

 the action of potash, these oil-bulbs 

 show much thickened cell-walls (Fig. 

 6 c). 



Among the fragments of pulp-cells 

 are seen a few bits of tissue of heavy- 

 walled, woody cells, forming a sort of 

 framework (Fig. 7) covered by a very 

 delicate, hyaline cell-membrane, often 

 enclosing a bubble of air (Fig. 7 a) ; 

 most of these fragments have portions 

 of spiral tissue attached (Fig. 7 d). 

 When these fragments are of some 

 thickness they appear as in Fig. 8 a, 

 caused by the thick border of under- 

 lying cells being seen so plainly 

 through the hyaline membrane of the 

 upper layer of cells. An ideal sec- 

 tion of these cells and diagram of 

 their arrangement is given in Fig. 8 

 at ^. A few fragments of deep red, 

 shell-like substance composed ot 

 small angular cells are seen (Fig. 9), 

 and are from the shell or hard coat- 

 ing of the seed. The great bulk of 

 the fragments, when a whole berry 

 has been ground up, will be found to 

 be composed of whitish or clear, 

 long, mostly quadrangular, somewhat 

 cuneate cells (Fig. 10 a), most of 

 which are filled with very minute 

 starch-grains (Fig. 10 d), which are 

 shown at Fig. 10 ^, as seen free, and 

 after the addition of iodine, by a ^- 

 inch objective : among these cells 



