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Among consumed-vegetable oils, RBDPO (refined, bleached and deodorized palm oil) is indicated containing higher level of 3-MCPDE and GE, which have been classified as potentially carcinogenic and/or genotoxic to human. Those contaminants in RBDPO are formed during deodorization process with high temperature and also correlate with chloride content and quality of CPO as raw material. The maximum limit for 3-MCPDE and GE content in vegetable oil has been set at 2500 and 1000 µg kg-1, and as low as 750 and 500 µg kg-1 when used for production of baby food and cereal-based foods for infants and young children. The mitigation of 3-MCPDE and GE in RBDPO is quite challenging for palm oil refineries in producing a good quality of palm oil in term of sensory, stability, safety, and nutritional value, especially in Indonesia. It has been proven that modification of conventional refining process can reduce the 3-MCPDE and GE content. They are including pre-treatment of CPO by water washing to reduce the chloride content, alkali neutralization to remove any acids present in the oil prior to deodorization, using neutral bleaching earth, adding antioxidants after bleaching to reduce free radical-mediated formation of 3-MCPDE and GE, lowering the deodorization temperature with a longer time, and even double bleaching and/or double deodorization of the palm oil. Post-refining treatment using specific adsorbents is also applied to remove the 3-MCPDE and GE. However, palm oil refineries have to apply combination of several mitigation strategies to adequately reduce the levels of 3-MCPDE and GE, including using good quality of CPO with low FFA, chloride, and oxidized components content.

Crude Palm Oil (CPO) is palm oil obtained from the extraction or compression process of oil palm fruit flesh and has not been purified. Palm oil is usually used for food, cosmetic industry, chemical industry, and animal feed industry. Increasingly open insight and increasing consumer awareness of the importance of food safety and quality assurance supported by technological developments and laboratory analysis methods, new types of contaminants in food products are also found. Currently, the Indonesian government is facing challenges regarding the issue of 3-monochloro-1,2-propanediol ester (3-MCPD Ester) and glycidyl ester (GE) in palm oil which can hamper Indonesia's palm oil trade in the future. The practice in the field affects the quality of CPO and the retrieval of low-quality CPO is mixed with high-quality CPO. And the length of time the process of pumping CPO from reclaimed tanks to VCT affects the quality of CPO. So this study aims to modify the pumping time and storage time of CPO from Reclaimed tanks to VCT by mixing samples from VCT (fresh CPO) and samples from Reclaimed tanks (lower quality CPO).

Pseudo-nitzschia is a cosmopolitan marine diatom which can cause the poisoning of humans, marine mammals, and birds through the production of the neurotoxin domoic acid and subsequent contamination of the marine food web. Severe poisoning events are induced when environmental conditions allow: (1) the rapid proliferation ('bloom') of resident toxic species of Pseudo-nitzschia, and/or (2) their enhanced toxin production, and (3) the conveyance of the toxin into prey items. The introduction of domoic acid into the food web was recognized as a public health concern along the coast of California following a Pseudo-nitzschia bloom and seabird mortality event in the Monterey Bay area in 1991, and blooms of Pseudo-nitzschia have since been observed in the region with regularity. Since the recognition of the public health concern posed by these recurrent harmful algal bloom (HAB) events, the California Department of Public Health (CDPH) has been charged with protecting the public from domoic acid intoxication through the Preharvest Shellfish Protection and Marine Biotoxin Monitoring Program. This regulatory program (1) conducts, surveys, classifies and monitors commercial shellfish growing areas, and (2) monitors numerous points along the California coastline for marine biotoxins in shellfish and toxigenic phytoplankton in the waters. While these regulatory efforts have successfully prevented significant injury to public health since they began, they remain relatively inefficient in terms of time, energy, and cost.This thesis begins with an investigation of the environmental factors that contribute to Pseudo-nitzschia bloom formation in Monterey Bay (Chapter 1). The identification of nitrate and river discharge as seasonal bloom factors motivated an explicit evaluation and contextualization of river nitrate loading within the 'upwelling-dominated' region of Monterey Bay (Chapter 2). Finally, a new monitoring technology, Solid Phase Adsorption Toxin Tracking (SPATT), is presented, developed primarily for use by public health managers for more effective and efficient monitoring of domoic acid, the toxin produced by Pseudo-nitzschia and the ultimate cause for concern (Chapter 3, with addendum).

Several lipases from microbial and plant, i.e Rhizomucor miehei, Pseudomonas sp., Candida antartica, rice bran, and Carica papaya latex (CPL) were examined for synthesis of omega-3 (n-3) PUFA-rich glyceride by hydrolysis and acidolysis reaction. Tuna oil was used in hydrolysis reaction, whereas tuna and palm oils were used as source of triglyceride (TAG) molecules and n-3 PUFA concentrate from tuna oil as source of EPA and DHA in acidolysis reaction.For hydrolysis reaction, the rice bran and CPL lipases showed the lowest hydrolytic activity of the tuna oil, whereas the R. miehei lipase showed the highest hydrolytic activity but was unable to hydrolyze EPA and DHA. On the contrary, the C. antartica and Pseudomonas sp. lipases acted stronger on hydrolysis of DHA ester bond than EPA.For acidolysis reaction, all the lipases showed ability to incorporate n-3 PUFA into tuna and palm oils. C. antartica lipase had the maximum DHA incorporation into tuna and palm oils, rice bran lipase had relatively similar ability with R. miehei lipase, and the CPL lipase had the lowest ability. This study proved that rice bran and CPL lipases also had transesterification activity and showed the feasibility of the rice bran lipase to be a biocatalyst for n-3 PUFA-rich glyceride production. Increasing the substrate ratio, of n-3 PUFA concentrate and tuna or palm oil, could increase the EPA and DHA incorporation. The R. miehei, rice bran, and CPL lipases unabled to incorporate DHA into DHA-containing glyceride molecule, whereas C. antartica lipase had the capability in high ratio of n-3 PUFA concentrate to oil. Therefore, the lipases were easier to incorporate n-3 PUFA into palm oil than tuna oil, since the TAG molecules of palm oil was not as complex as tuna oil. It could be suggested that the lipases did not only have acyl chain and positional specificity, but also the whole glyceride structure specificity.