Physical refining of conventional, organic and sustainable (RSPO) crude palm oil : addition of pre-treatment, reduction of contaminants and oil quality

Orientador: Klicia Araujo SampaioDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: O óleo de palma (Elaeis guineensis) possui intensa coloração alaranjada devido ao alto teor de carotenoides. A forma de cultivo mais comum para a palmeira oleaginosa é realizada através do cultivo convencional, onde faz-se o uso de fertilizantes. Atualmente, o óleo de palma também pode ser obtido através do cultivo orgânico (sem uso de adubos químicos e agrotóxicos) ou através cultivos sustentáveis, como a Mesa Redonda para Produção Sustentável de Óleo de Palma (Roundtable for Sustainable Palm Oil-RSPO). Devido a sua elevada acidez, o óleo de palma é geralmente submetido ao refino físico, o qual faz uso de altas temperaturas (240-260 °C) e baixas pressões (2-4 mbar). No entanto, essas condições extremas de processo, juntamente com a composição do óleo (TAG, DAG e MAG) e precursores clorados, podem influenciar na formação de contaminantes da classe de monocloropropanodiois (3-MCPD e 2-MCPD) e ésteres de glicidol (GE). A Agência Internacional de Pesquisa sobre o Câncer (IARC) classifica o 3-MCPD como possível carcinógeno humano (grupo 2B), o glicidol como provável carcinógeno humano (grupo 2A) e o 2-MCPD ainda sem limite tóxico. Nesse sentido, a adição da etapa de lavagem tem sido avaliada como alternativa à redução de impurezas polares presentes no óleo, como os compostos clorados hidrofílicos. Dessa forma, o objetivo deste trabalho foi avaliar a aplicação dessa etapa antes do refino físico em óleo de palma bruto (orgânico, convencional e RSPO) armazenados a 6 meses e 0 meses (óleos frescos), para reduzir a formação de contaminantes (3-MCPD, 2-MCPD e GE). Inicialmente, a proporção de água a ser usada e o tipo de terra de branqueamento a ser empregado foi determinado. Posteriormente, os óleos foram submetidos ao refino tradicional e logo seguiram para análises de qualidade (acidez, cor, índice de estabilidade oxidativa, umidade, perfil de ácidos graxos, composição em acilgliceróis, índice de branqueabilidade, teor de minerais). A água de lavagem seguiu para análise de cloreto e pH, onde a maior remoção de cloreto ocorreu com o uso de 30% w/w de água e a terra ácida ativada foi a que melhor reduziu Fe e P. Após a desodorização dos óleos (orgânico, convencional e RSPO) com armazenamento de 6 meses, os valores de contaminantes ficaram entre 3,19-5,44 mg/kg para 3-MCPDE, 1,35-2,49 mg/kg para 2-MCPDE e 0,27-0,77 mg/kg de GE. Para os óleos frescos, 3-MCPDE foi 0,97-2,21 mg/kg, 2-MCPDE de 0,41-1,07 mg/kg e GE entre 0,14-0,22 mg/kg. Melhores resultados obtidos pelos óleos frescos foi encontrado também em análises de qualidade, o que indica que a lavagem realizada pode ter diminuído o teor de cloretos e o tempo de armazenamento pode ter influenciado em óleos menos deteriorados e de melhor qualidade, juntamente com menores teores de contaminantes (3-MCPDE, 2-MCPDE e GE). Além disso, quando comparado os óleos em relação aos três diferentes tipos de cultivo (orgânica, convencional e sustentável (RSPO)), esses não mostraram diferença nos teores de contaminantes; indicando assim, que os prováveis precursores podem surgir a partir de outras fontes e não somente através do cultivoAbstract: Palm oil (Elaeis guineensis) has intense orange coloration due to the high content of carotenoids. The most commom form of cultivation for the oleaginous palm tree is through conventional cultivation, where fertilizers are used. Currently, palm oil can also be obtained through organic cultivation (without the use of chemical fertilizers and agrochemicals) or through sustainable crops, such as the Roundtable for Sustainable Palm Oil (RSPO). Due to its high acidity, palm oil is generally subjected to physical refining, which makes use of high temperatures (240-260 °C) and low pressures (2-4 mbar). However, these extreme process conditions, together with the oil composition (TAG, DAG and MAG) and chlorinated precursors can influence the formation of contaminants of the class of monochloropropanediols (3-MCPD and 2-MCPD) and glycidol esters (GE). The International Agency for Research on Cancer (IARC) classifies 3-MCPD as a possible human carcinogen (group 2B), glycidol as a probable human carcinogen (group 2A) and 2-MCPD with no toxic limit. In this sense, addition of the washing step has been evaluated as an alternative to the reduction of polar impurities resent in the oil, such as hydrophilic chlorinated compounds. Thus, the objective of this work was to evaluate the application of this step before physical refining in crude palm oil (organic, conventional and RSPO) stored at 6 months and 0 months (fresh oils) to reduce the formation of contaminants (3-MCPD, 2-MCPD and GE). Iniatially, the proportion of water to be used and the type of bleaching earth to be employed was determined. Afterwards, the oils were submitted to traditional refining and soon followed for quality analyses (acidity, color, oxidative, stability index, moisture content, fatty acid profile, acylglycerols composition, bleachability index, mineral content). The washing water was followed for chloride and pH analysis, where the greatest removal of chloride occurred with the use of 30% w / w of water and the activated acid soil was the one that reduced the Fe and P. After deodorization of the oils (organic, conventional and RSPO) with storage for 6 months, contaminant values were between 3.19-5.44 mg / kg for 3-MCPDE, 1.35-2.49 mg / kg for 2-MCPDE and 0.27-0.77 mg / kg GE. For fresh oils, 3-MCPDE was 0.97-2.21 mg / kg, 2-MCPDE of 0.41-1.07 mg / kg and GE between 0.14-0.22 mg / kg. The best results obtained by the fresh oils were also found in quality analyzes, which indicates that the washing done may have decreased the chloride content and the storage time may have influenced less deteriorated oils of better quality, together with lower levels of contaminants (3-MCPDE, 2-MCPDE and GE). Moreover, when compared to the oils in relation to the three different types of cultivation (organic, conventional and sustainable (RSPO)), these did not show any difference in contaminant contents, thus indicating that the probable precursors may arise from other sources and not only through cultivationMestradoEngenharia de AlimentosMestra em Engenharia de Alimentos132995/2017-4CNP

Washing bleached palm oil to reduce monochloropropanediols and glycidyl esters

The formation of toxic compounds, potentially carcinogenic, during food processing has been considered an important food safety issue. Among them, particular attention has been given to 3-monochloropropane-1,2-diol esters (3-MCPDE), 2-monochloropropane-1,3-diol esters (2-MCPDE) and glycidyl esters (GE), which can be formed during vegetable oil refining, especially palm oil. These substances may pose a health risk to humans due to their toxicity and carcinogenicity. The aim of this study was to investigate the effect of washing bleached palm oil (BPO) with different solvents, and evaluate the reduction of 3-MCPDE, 2-MCPDE and GE as well as assess the quality parameters of the final product. For this purpose, we used two types of washing with different solvents. A single washing was carried out in one step and a double washing in two steps using a solvent gradient. Single washing had a limited reduction in the levels of 3-MCPDE and 2-MCPDE and resulted in an increased level of GE, whereas double washing slightly reduced 3-MCPDE and 2-MCPDE and resulted in a significant reduction of GE levels. The reduction achieved in this study was up to 17.1% for 3-MCPDE, 56.4% for 2-MCPDE and 76.9% for GE levels. The reduction of 3-MCPDE and 2-MCPDE might be due to the removal of part of the ethanol-soluble chlorinated precursors from the oil which suggests that highly lipophilic forms of these substances are present in BPO. The substantial reduction on GE levels might be associated with the removal of the precursors present in the oil such as diacylglycerols. Thus, the washing treatment could be used as a supplementary strategy to reduce processing contaminants from palm oil, especially GEs362244253CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2016/239583; 2017/26675-5; 2014/2152-0001This work was supported by the São Paulo Research Foundation under Grant numbers [2016/239583, 2017/26675-5, 2014/2152-0]. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) - Financial Code [001; 33003017027P1 - PROEX0082040 and FAEPEX (3272/17)