European Journal of Lipid Science and Technology, Oct 13, 2017
Traditionally, pumpkin seed oil is obtained by pressing the seeds after a roasting pretreatment, ... more Traditionally, pumpkin seed oil is obtained by pressing the seeds after a roasting pretreatment, at temperatures up to 150 C. However, the appropriate temperatures and roasting times are under discussion. In this study, oils from seeds roasted at different temperatures (60-150 C) are compared with oil from nonroasted seeds. At higher roasting temperatures, lower roasting times are required to release the oil. Both, for tocopherols and phenolic compounds, no decreasing trend with the increasing roasting temperature are observed. In contrast, the oil from non-roasted seeds have relatively low levels of tocopherols and phenolics and lacked the typical aroma. Levels of polyaromatic hydrocarbons (PAHs) are very low, ranging from not detected in oil from non-roasted seeds to 13.8 μg kg À1 in the oil from seeds roasted at 150 C. Therefore, the choice between the studied roasting conditions may depend rather on sensory evaluations than on the content of antioxidants or of PAHs. Practical Applications: The process of the production of virgin pumpkin oil is based on a thermal treatment of the ground seeds, favoring the separation of the lipid fraction, and giving a typical aroma of the roasted oil. Results of this research provide important information regarding the influence of roasting conditions on the quality and safety of the oil. Roasting pumpkin seeds increased the tocopherol and phenols content in the pumpkin oil, with no significant formation of PAHs. The information will be valuable and important for not only for the pumpkin oil production, but also for all the seeds submitted to a roasting treatment before extraction.
Lebensmittel-Wissenschaft & Technologie, Jun 1, 2019
Degumming is a necessary refining step for all crude vegetable oils. Purifine® PLC is a new enzym... more Degumming is a necessary refining step for all crude vegetable oils. Purifine® PLC is a new enzyme used for industrial oil degumming. In the present study, enzymatic degumming trials were performed on crude corn oil using a commercial phospholipase C enzyme Purifine® PLC with the aim of determining its optimum process conditions. Enzymatic degumming applying 200 mg/kg of Purifine® PLC during 120 min at 60 °C, and a pH of 5.7 using chemical conditioning, resulted in a residual phosphorus content of 27 mg/kg and an absolute diacylglycerol increase of 0.54 wt%. Compared to water degumming, enzymatic degumming with Purifine® PLC provided a better degumming (67 mg/kg versus 27 mg/kg) and an increase in the diacylglycerol content. The pH adjustment of crude corn oil performed by means of a caustic pretreatment was not able to keep the pH at an optimal stable value due to the continuous release of acidic phosphate groups. Analysis of the composition of remaining phospholipids in the gums fraction showed that Purifine® PLC could effectively convert phosphatidylcholine and phosphatidylethanolamine into diacylglycerols, whereas it could not convert phosphatidylinositol and phosphatidic acid. These results confirm that Purifine® PLC degumming is a commercially feasible alternative to traditional degumming processes.
Renewable Bioresources: scope and modification for non-food applications is the first text to con... more Renewable Bioresources: scope and modification for non-food applications is the first text to consider the broad concept of renewable materials from the socioeconomic aspects through to the chemical production and technical aspects of treating different raw products. The text sets the context of the renewables debate with key opening chapters on green chemistry, and the current situation of US and EU policy regarding sustainability and industrial waste. The quantitative and technical scope and production of renewable resources is then discussed with material looking at integral valorisation, the primary production of raw materials, downstream processing, and the
Abstract: The objective of this chapter is to provide an overview of the conversion of various li... more Abstract: The objective of this chapter is to provide an overview of the conversion of various lipid sources (edible and non-edible) into biodiesel using traditional and new technologies emphasizing the quality standards mainly dependent on the used feedstock and technology, processing and purification.
Synthesis of Substituted Cyclopropylphosphonates by Michael Induced Ring Closure (MIRC) Reactions... more Synthesis of Substituted Cyclopropylphosphonates by Michael Induced Ring Closure (MIRC) Reactions.-Michael addition of trialkyl phosphites to β-bromoalkylidene derivatives (II) generates a zwitterionic intermediate which readily undergoes cyclization to cyclopropyl phosphonates such as (IV). They are of interest as synthons in natural product and drug preparation.-(STEVENS, CHRISTIAN V.
Good quality is one of the main problems in every stage of freezing berries. On the basis of work... more Good quality is one of the main problems in every stage of freezing berries. On the basis of worked out functional analysis of freezing, it is possible to optimize regulation possibilities of heat processes for a particular kind of berries. Raspberries, red currants and black currants were used in the research. 10.0 cm thick bulk frozen berry layer was chosen for studying the freezing process. The freezing dynamics of berries is characterised by temperature measurements in a layer and on its surface. As a result of the research the developed equipment for the measurements of heat flow are approbated. It is necessary to investigate suitability of different cultivars to freezing and influence of freezing to quality of final product. Experimentally verified results will help to explain and predict physical processes in berries during freezing.
Treatment of N‐1‐(2, 2‐dichloroalkylidene)t.butylamines 1a‐c with excess methanolic sodium methox... more Treatment of N‐1‐(2, 2‐dichloroalkylidene)t.butylamines 1a‐c with excess methanolic sodium methoxide under reflux afforded mainly a mixture of α‐methoxy‐α,β‐unsaturated aldimines 2a‐c and the rearrangement products 3, besides small amounts of N‐t.butyl 2‐chloroamides 4 and N‐t.butyl 2‐chloro imidates 6. On the other hand, N‐1‐(2, 2‐dichlorobutylidene)t.butylamines 1d‐e gave α‐chlo‐ro‐α, β‐unsaturated aldimines, while α, α‐dichloropropylidene t.butylamine 9 provided mainly the α‐methoxy‐α,β‐unsaturated aldimine 11 next to the α‐me‐thoxyamide 12, α, α‐dimethoxyaldimine 10 and the rearrangement product 13. The reaction mechanisms are discussed.
A general synthetic route to N‐1‐(2,2‐dichloroalkylidene) amides is described, starting from alip... more A general synthetic route to N‐1‐(2,2‐dichloroalkylidene) amides is described, starting from aliphatic 2,2‐dichloroaldehydes and an appropriate N‐unsubstituted amide. The adducts thus formed were converted into N‐(1,2,2‐trichloroalkyl) amides with thionylchloride and subsequently dehydrohalogenated with triethylamine. These N‐acyl α,α‐dichloroaldimines were found to be very apt to nucleophilic addition at the activated carbon‐nitrogen double bond, producing stable adducts. The configuration of the adducts in solution was determined by NMR‐spectroscopy. Treatment of the title compounds with lithium aluminium hydride in diethylether afforded 1,2‐dialkylaziridines. The reactivity of these N‐acyl α,α‐dichloroaldimines was compared with the reactivity of the N‐alkyl analogues and the corresponding oxygen analogues, i.e. α,α‐dihalogenated aldehydes.
Fish oil has the advantage to contain high concentrations of ω3 fatty acids (EPA, DHA), anti-oxyd... more Fish oil has the advantage to contain high concentrations of ω3 fatty acids (EPA, DHA), anti-oxydants and lipophilic vitamins. It has been shown that the intake of these products can reduce the risk of cardiovascular diseases, arterial thrombosis, autoimmune and inflammatory problems.
The valorization of by-products helps to reduce waste, to minimize the footprint of the technolog... more The valorization of by-products helps to reduce waste, to minimize the footprint of the technology and to add value through the production of biodiesel as an energy carrier. Alternative resources such as deodorizer distillates can partially replace the traditional feedstocks for the production of biodiesel, but require application of new technologies and/or additional purification steps. This chapter proposes to offer an overview of different methodologies used to convert deodorized distillates to biodiesel/biofuels and to recover the valuable minor components such as sterols, squalene and tocopherols. Key words: biodiesel production from deodorizer distillates, conversion routes for high-acidity feedstocks, recovery of the minor components. 22.1 Composition of deodorizer distillate Crude vegetable oils contain triacylglycerols (TAG) as major component and various minor components such as diacylglycerols (DAG), monoacylglycerols (MAG), free fatty acids (FFA), phospholipids, tocopherols, sterols, squalene, color pigments, waxes, aldehydes, ketones, triterpene alcohols and metals which may affect the quality of the final product. These minor components are removed partially or entirely by either physical (RBD) or chemical (NBD) refining. Deodorizer distillate (DD) is one of the side streams obtained in the final step of refining of vegetable oils used to remove odoriferous components and to reduce the free acidity in order to make the vegetable oils suitable for human consumption. It was observed that the composition of DD is dependent on the oil source, the refining routes (physical or chemical) and the deodorizer operating conditions (De
European Journal of Lipid Science and Technology, Oct 13, 2017
Traditionally, pumpkin seed oil is obtained by pressing the seeds after a roasting pretreatment, ... more Traditionally, pumpkin seed oil is obtained by pressing the seeds after a roasting pretreatment, at temperatures up to 150 C. However, the appropriate temperatures and roasting times are under discussion. In this study, oils from seeds roasted at different temperatures (60-150 C) are compared with oil from nonroasted seeds. At higher roasting temperatures, lower roasting times are required to release the oil. Both, for tocopherols and phenolic compounds, no decreasing trend with the increasing roasting temperature are observed. In contrast, the oil from non-roasted seeds have relatively low levels of tocopherols and phenolics and lacked the typical aroma. Levels of polyaromatic hydrocarbons (PAHs) are very low, ranging from not detected in oil from non-roasted seeds to 13.8 μg kg À1 in the oil from seeds roasted at 150 C. Therefore, the choice between the studied roasting conditions may depend rather on sensory evaluations than on the content of antioxidants or of PAHs. Practical Applications: The process of the production of virgin pumpkin oil is based on a thermal treatment of the ground seeds, favoring the separation of the lipid fraction, and giving a typical aroma of the roasted oil. Results of this research provide important information regarding the influence of roasting conditions on the quality and safety of the oil. Roasting pumpkin seeds increased the tocopherol and phenols content in the pumpkin oil, with no significant formation of PAHs. The information will be valuable and important for not only for the pumpkin oil production, but also for all the seeds submitted to a roasting treatment before extraction.
Lebensmittel-Wissenschaft & Technologie, Jun 1, 2019
Degumming is a necessary refining step for all crude vegetable oils. Purifine® PLC is a new enzym... more Degumming is a necessary refining step for all crude vegetable oils. Purifine® PLC is a new enzyme used for industrial oil degumming. In the present study, enzymatic degumming trials were performed on crude corn oil using a commercial phospholipase C enzyme Purifine® PLC with the aim of determining its optimum process conditions. Enzymatic degumming applying 200 mg/kg of Purifine® PLC during 120 min at 60 °C, and a pH of 5.7 using chemical conditioning, resulted in a residual phosphorus content of 27 mg/kg and an absolute diacylglycerol increase of 0.54 wt%. Compared to water degumming, enzymatic degumming with Purifine® PLC provided a better degumming (67 mg/kg versus 27 mg/kg) and an increase in the diacylglycerol content. The pH adjustment of crude corn oil performed by means of a caustic pretreatment was not able to keep the pH at an optimal stable value due to the continuous release of acidic phosphate groups. Analysis of the composition of remaining phospholipids in the gums fraction showed that Purifine® PLC could effectively convert phosphatidylcholine and phosphatidylethanolamine into diacylglycerols, whereas it could not convert phosphatidylinositol and phosphatidic acid. These results confirm that Purifine® PLC degumming is a commercially feasible alternative to traditional degumming processes.
Renewable Bioresources: scope and modification for non-food applications is the first text to con... more Renewable Bioresources: scope and modification for non-food applications is the first text to consider the broad concept of renewable materials from the socioeconomic aspects through to the chemical production and technical aspects of treating different raw products. The text sets the context of the renewables debate with key opening chapters on green chemistry, and the current situation of US and EU policy regarding sustainability and industrial waste. The quantitative and technical scope and production of renewable resources is then discussed with material looking at integral valorisation, the primary production of raw materials, downstream processing, and the
Abstract: The objective of this chapter is to provide an overview of the conversion of various li... more Abstract: The objective of this chapter is to provide an overview of the conversion of various lipid sources (edible and non-edible) into biodiesel using traditional and new technologies emphasizing the quality standards mainly dependent on the used feedstock and technology, processing and purification.
Synthesis of Substituted Cyclopropylphosphonates by Michael Induced Ring Closure (MIRC) Reactions... more Synthesis of Substituted Cyclopropylphosphonates by Michael Induced Ring Closure (MIRC) Reactions.-Michael addition of trialkyl phosphites to β-bromoalkylidene derivatives (II) generates a zwitterionic intermediate which readily undergoes cyclization to cyclopropyl phosphonates such as (IV). They are of interest as synthons in natural product and drug preparation.-(STEVENS, CHRISTIAN V.
Good quality is one of the main problems in every stage of freezing berries. On the basis of work... more Good quality is one of the main problems in every stage of freezing berries. On the basis of worked out functional analysis of freezing, it is possible to optimize regulation possibilities of heat processes for a particular kind of berries. Raspberries, red currants and black currants were used in the research. 10.0 cm thick bulk frozen berry layer was chosen for studying the freezing process. The freezing dynamics of berries is characterised by temperature measurements in a layer and on its surface. As a result of the research the developed equipment for the measurements of heat flow are approbated. It is necessary to investigate suitability of different cultivars to freezing and influence of freezing to quality of final product. Experimentally verified results will help to explain and predict physical processes in berries during freezing.
Treatment of N‐1‐(2, 2‐dichloroalkylidene)t.butylamines 1a‐c with excess methanolic sodium methox... more Treatment of N‐1‐(2, 2‐dichloroalkylidene)t.butylamines 1a‐c with excess methanolic sodium methoxide under reflux afforded mainly a mixture of α‐methoxy‐α,β‐unsaturated aldimines 2a‐c and the rearrangement products 3, besides small amounts of N‐t.butyl 2‐chloroamides 4 and N‐t.butyl 2‐chloro imidates 6. On the other hand, N‐1‐(2, 2‐dichlorobutylidene)t.butylamines 1d‐e gave α‐chlo‐ro‐α, β‐unsaturated aldimines, while α, α‐dichloropropylidene t.butylamine 9 provided mainly the α‐methoxy‐α,β‐unsaturated aldimine 11 next to the α‐me‐thoxyamide 12, α, α‐dimethoxyaldimine 10 and the rearrangement product 13. The reaction mechanisms are discussed.
A general synthetic route to N‐1‐(2,2‐dichloroalkylidene) amides is described, starting from alip... more A general synthetic route to N‐1‐(2,2‐dichloroalkylidene) amides is described, starting from aliphatic 2,2‐dichloroaldehydes and an appropriate N‐unsubstituted amide. The adducts thus formed were converted into N‐(1,2,2‐trichloroalkyl) amides with thionylchloride and subsequently dehydrohalogenated with triethylamine. These N‐acyl α,α‐dichloroaldimines were found to be very apt to nucleophilic addition at the activated carbon‐nitrogen double bond, producing stable adducts. The configuration of the adducts in solution was determined by NMR‐spectroscopy. Treatment of the title compounds with lithium aluminium hydride in diethylether afforded 1,2‐dialkylaziridines. The reactivity of these N‐acyl α,α‐dichloroaldimines was compared with the reactivity of the N‐alkyl analogues and the corresponding oxygen analogues, i.e. α,α‐dihalogenated aldehydes.
Fish oil has the advantage to contain high concentrations of ω3 fatty acids (EPA, DHA), anti-oxyd... more Fish oil has the advantage to contain high concentrations of ω3 fatty acids (EPA, DHA), anti-oxydants and lipophilic vitamins. It has been shown that the intake of these products can reduce the risk of cardiovascular diseases, arterial thrombosis, autoimmune and inflammatory problems.
The valorization of by-products helps to reduce waste, to minimize the footprint of the technolog... more The valorization of by-products helps to reduce waste, to minimize the footprint of the technology and to add value through the production of biodiesel as an energy carrier. Alternative resources such as deodorizer distillates can partially replace the traditional feedstocks for the production of biodiesel, but require application of new technologies and/or additional purification steps. This chapter proposes to offer an overview of different methodologies used to convert deodorized distillates to biodiesel/biofuels and to recover the valuable minor components such as sterols, squalene and tocopherols. Key words: biodiesel production from deodorizer distillates, conversion routes for high-acidity feedstocks, recovery of the minor components. 22.1 Composition of deodorizer distillate Crude vegetable oils contain triacylglycerols (TAG) as major component and various minor components such as diacylglycerols (DAG), monoacylglycerols (MAG), free fatty acids (FFA), phospholipids, tocopherols, sterols, squalene, color pigments, waxes, aldehydes, ketones, triterpene alcohols and metals which may affect the quality of the final product. These minor components are removed partially or entirely by either physical (RBD) or chemical (NBD) refining. Deodorizer distillate (DD) is one of the side streams obtained in the final step of refining of vegetable oils used to remove odoriferous components and to reduce the free acidity in order to make the vegetable oils suitable for human consumption. It was observed that the composition of DD is dependent on the oil source, the refining routes (physical or chemical) and the deodorizer operating conditions (De
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