191S.] AGRICULTURAL CHEMISTRY AGROTECHNY. 807 



Influence of time of harvest, drying, and freezing of spearmint upon the 

 yield and odorous constituents of the oil, F. Rahak {Jour. Indus, and Engin. 

 Cliem., 10 (lOlS), No. J,, pp. 2?'5-r?9).— Investigations of spearmint oil having 

 indicated that esters or alcoliolic compounds play an important part as car- 

 riers of the aroma and flavor, a study of the plant was undertaken at Arlington 

 Farm, Va., to obtain information regarding the effect of time of harvest, drying 

 of the plant, and frost action upon the constituents as v^^ell as upon the yield 

 and physical properties of the oils. The plants were harvested and distilled 

 at three different stages of growth, viz, budding, flowering, and fruiting. 



It was found that the yield of oil is affected by seasonal conditions, being 

 distinctly higher in some seasons than in others. The maximum content of oil 

 is present during the flowering period, the tops containing the largest amount 

 of oil. Esterification and alcohol formation tend to increase, and yield of total 

 oil to decrease, during the maturing and drying of the plants. Freezing of the 

 plant produces a marked increase in the formation of the odor-bearing esters 

 and alcohols. 



A preliminary study of the Philippine coconut oil industry, P. A. Villyar 

 {Philippine Agr. and Forester, 6 {1917), No. 2-3, pp. 66-83, figs. 10). — A study 

 of the factory conditions in some oil-producing localities in the Province of 

 Laguua is reported. The article includes a description of the native hand-press 

 and machine-press methods with illustrative plates, and an efficiency study of 

 11 native factories based on field investigation of methods practiced and appli- 

 ances used, on laboratory analyses of samples obtained in the field investiga- 

 tion, and on a comparison of the native methods of coconut oil extraction with 

 the modern methods. 



As a result of the study the author offers the following suggestions for the 

 improvement of the coconut oil industry : 



" Cooperation is urged as a remedy against the loss of money due to poor 

 cultural methods, to the improper preparation and handling of coconut prodxicts, 

 and to the combined work of the middlemen. Adoption of modern methods is 

 essential to increase the copra and oil production. Nuts for copra and oil 

 manufacture must be properly aged to insure a maximum yield. The passing 

 of law.'s facilitating the transportation of coconut products should be demanded 

 from the proper authorities." 



The manufacture of nut margarin, G. H. Pickabd {Amer. Food Jour., 13 

 {1918), No. 1, pp. 16-19). — This article includes a description of the raw ma- 

 terials used and the general processes of manufacture of nut margarin, with a 

 discussion of its digestibility and food value. 



The utilization of waste tomato seeds and skins, F. Rabak {U. S. Dept. 

 Agr. Bui. 632 {1917), pp. 15). — This includes a review of work already done in 

 foreign countries on the utilization of tomato waste, an investigation of the 

 annual output of tomato refuse in the United States, a comparison of methods 

 of separating the ingredients of the waste, and chemical analyses and value of 

 the most important ingredients. 



It is estimated that the annual dry waste from the tomato industries in the 

 United States is about l,.50O tons of seeds and 1.800 tons of skins. From the 

 seeds can be extracted an oil averaging by the continuous extraction process 

 22 per cent of the dry seeds. 



The refined oil is similar in constants to cottonseed, soy-bean, sesame, and 

 corn oils. Digestibility experiments by the Office of Home Economics show a 

 coefficient of digestibility of 97, comparing favorably with the common edible 

 oils. Ii possesses a certain value as a paint or varnish oil and makes a soap 

 of good texture. The residue after extraction of the oil compares favorably 

 65162°— 18 2 



