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This chapter presents the results of trials conducted to investigate the efficacy of sanitation in basal stem rot (BSR; Ganoderma sp.) management at Bah Lias Research Station in North Sumatra, Indonesia, over a period of several years. The trials were designed to assess the relative importance of various tissue remnants (from stumps, trunks and roots) from the old palm stand as potential sources of inoculum at replanting. Molecular fingerprinting techniques became available which allowed confirmation of the origin of the pathogen in infected seedlings. Disease development and overt symptom appearance depended on the size of palm when it becomes infected, its continued growth vigour and the size of the inoculum. Small seedlings close to large disease sources were rapidly killed. Larger, rapidly growing plants were also affected, but often did not die quickly. The results confirmed that the times of greatest significance for BSR control are: (1) soon after planting, when suitable inocula remain in the ground from the previous planting (oil palm stumps or root debris); and (2) later in the planting cycle, when root contact is made with Ganoderma-colonized sections of palm trunks resting on the ground in rows (windrows).

Fat content and fatty acid (FA) composition of 100 common items in 17 food categories from the Canadian retail market were determined. Of these, 52 samples were made from partially hydrogenated fat. Their fat (in parentheses) and trans FA levels were as follows: breads (3.7% fat) 15.7%, hamburger buns (5.5% fat) 26.3%, cakes (8.7-36.7% fat) 10.1-25.7%, candies/chocolates (27.1% fat) 11.1%, cereals (1.3-12.9% fat) 9.2-33.7%, cookies (5.0-40.5% fat) 7.6-38.7%, crackers (9.2-33.0% fat) 13.8-35.4%, donuts (16.6-29.6% fat) 27.7-32.7%, french fries (pre-cooked) (4.3-4.5% fat) 32.8-42.8%, muffins (12.5-23.7% fat) 16.5-24.2%, pizza crusts (6.0-7.2% fat) 22.1-28.8%, shortenings (100% fat) 17.4-20.2%, potato chips (33.2-40.0% fat) 29.7-39.7%, and corn chips (25.0-34.2%) 29.9-33.9%. Generally the sum of saturated and trans FA in the food items made with partially hydrogenated fat was higher than that of the corresponding food items made with unhydrogenated oils. The higher levels of saturates plus trans were at the expense of the essential fatty acids (EFA). The high-fat foods, such as cakes, cookies, crackers, donuts and potato chips, made with partially hydrogenated fat, were substantially lower in EFA and contained relatively higher levels of trans polyunsaturated fatty acids (PUFA). In some samples of potato chips and french fries, the level of trans PUFA was almost the same or more than the sum of linoleic and linolenic acids.

A combined capillary gas liquid chromatography (GLC) and infrared spectrophotometry (IR) method is described for the determination of c/s and transoctadecenoic acids in margarines made from partially hydrogenated vegetable oils. The total trans-unsaturation of margarine fatty acid methyl esters determined by IR, with methyl elaidate as the external standard, was correlated to the capillary GLC weight percentages of the component trans fatty acid methyl esters by the mathematical formula: IR trans = %18:1t + 0.84 X %18.2t + 1.74 X %18:2tt + 0.84 X %18:3t where 0.84, 1.74 and 0.84 are the correction factors which relate the GLC weight percentages to the IR trans-equivalents for mono-transoctadecadienoic (18:2t), trans, trans-octadecadienoic (18:2tt) and mono-trans-octadecatrienoic (18:3t) acids, respectively. This formula forms the basis for the determination of total trans-and c/s-octadecenoic acids in partially hydrogenated vegetable oils. From the weight percentages of 18:2t, 18:2tt and 18:3t determined by capillary GLC on a cyanosilicone liquid phase and the total trans-unsaturation by IR, the percentage of the total trans-octadecenoic acids (18:1t) is calculated using the formula. The difference between the total octadecenoic acids (18:1), determined by capillary GLC, and the 18:1t gives the total c/s-octadecenoic acids.

This chapter describes a preliminary comparison of methods for assessing the biodegradation of oil palm stem (OPS) by macroscopic fungi in vitro as a first step in developing a practical process in vivo. Many of the methods described (enzyme assays, growth assessment, weight loss determination, ergosterol analysis, respirometry analysis and enzyme digestibility analysis) have been used in conjunction with OPS for the first time. Although the studies were conducted on OPS, most of the results could also probably be applied to oil palm boles, which cause similar problems to OPS, although they are even more difficult to treat as they are firmly embedded in the soil by the root system. This chapter reflects the experiences of the authors in southeast Asia, and in particular Indonesia and Malaysia.