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Emollient Esters and Oils
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
John Carson, Kevin F. Gallagher
Vegetable oils are more likely to be fluid at room temperature. This fluidity is conferred by the composition and nature of their component fatty acids. Vegetable oils typically contain a higher proportion of unsaturated fatty acid triglyceride esters than animal fats. These unsaturated fatty acid esters contain at least one carbon-to-carbon double bond, so they are not "saturated" with hydrogen. The presence of this double bond creates a kink in the fatty chain. This kink, or bend, will make it more difficult for the molecule to form an ordered structure, which is necessary for solidification. A simple comparison between a saturated fatty acid, stearic acid, and an almost identical (but for two hydrogen atoms) unsaturated fatty acid, oleic acid, is shown in Figure 3.
Hydrothermal Liquefaction
Published in Rajeev Pratap Singh, Vishal Prasad, Barkha Vaish, Advances in Waste-to-Energy Technologies, 2019
Saqib Sohail Toor, Federica Conti, Ayaz Ali Shah, Tahir Hussain Seehar, Lasse Aistrup Rosendahl
Heterocyclic compounds are formed by Maillard reaction between reducing sugars and amino acids. Branched chain amides are converted from the reaction of fatty acids with amines that are produced from amino acids [17]. Ketones are formed by hydrolysis and dehydration of sugars, or by decarboxylation of amino acids to form keto-acids and then ketones by further decarboxylation. Aldehydes are formed through the same route or via isomerization of ketones. Fatty acid esters are derived from the reactions between alcohols and fatty acids. It has been experienced from several studies that the esters tend to become dominant compounds, when solvents other than water, like methanol or ethanol, are used for degradation of organic matter [16]. Phenols and their associated derivatives are converted from hydrolysis, dehydration, and ring closure reactions of lignin and cellulose [13]. Fatty acids are produced by the hydrolysis of lipids, that later on converted into long hydrocarbons via decarboxylation [18].
Microwave Mediated Biodiesel Production
Published in Veera Gnaneswar Gude, Microwave-Mediated Biofuel Production, 2017
Fatty acid methyl esters can be transformed into a variety of useful chemicals, and raw materials for further synthesis, as shown in Figure 19 (Schuchardt et al. 1998). The alkanolamides, whose production consumes the major part of the methyl esters produced in the world, have a direct application as non-ionic surfactants, emulsifying, thickening and plastifying agents, etc. The fatty alcohols are applied as pharmaceutical and cosmetics additives (C16-C18), as well as lubricants and plastifying agents (C6-C12), depending on the length of their carbon chain. The isopropyl esters are also applied as plastifying agents and emollients. However, they cannot be produced in a convenient way by esterification of fatty acids, because an azeotrope formed by water and isopropanol avoids the recycling of the alcohol. Fatty acid methyl esters are further used in the manufacture of carbohydrate fatty acid esters (sucrose polyesters), which can be applied as non-ionic surfactants or edible non-calorific oils, and can be used as an alternative fuel substitute for diesel engines which is called biodiesel.
Experimental study on lubrication performance of main components of biodiesel
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Yonghui Wu, Fashe Li, Wenchao Wang, Zihao Ni, Baoping Ding, Huicong Zhang
All samples were prepared by esterification; its principle is to get fatty acid esters by heating the mixture of fatty acid and alcohol through the action of catalyst. Using methyl palmitate as an example, mechanism of esterification reaction between palmitic acid and methanol is shown in Figure 1. First, methanol and palmitic acid were mixed in a 40:1 ratio within three-necked flask and used p-toluenesulfonic acid as a catalyst. The mixture was continuously stirred at a speed of 120 r/min and keep at a temperature of 85°C. Esterification process was carried out for 125 min. After the reaction, ethyl acetate was added to dissolve the unreacted reagent and the excess liquid was removed using a rotary evaporator. After the liquid was extracted, the methyl palmitate was dried in an oven at 100°C for 20 min to remove the remaining water. The conversion rate of the sample was affected by reaction temperature, reaction time, catalyst dosage, and molar ratio of methanol to palmitic acid. The optimum reaction conditions were obtained by single-factor test. First, temperature factor was varied while the other factors were fixed to obtain the optimal reaction temperature. Then other single factors vary to obtain the best reaction time, catalyst dosage, and molar ratio of alcohol to acid.
Physical stability characteristics of sunflower oil-in-water emulsion containing sodium chloride, stabilized by gelatinized bambara groundnut flour
Published in Cogent Engineering, 2019
Oladayo Adeyi, Daniel I.O. Ikhu-Omoregbe, Victoria Adaora Jideani
An increasingly growing area in food emulsion technology research is finding new alternatives for improving the stability and rheological properties of emulsions. The effectiveness and functionalities of synthetic surfactants such as acyl lactylates, dioctyl sodium sulfosuccinate, propylene glycol monoesters, sucrose esters and sorbitan esters have made them find applications as food emulsifier and modifiers in food applications (Akoh & Swanson, 1994). There have been reports of polyglycerol fatty acid ester, polyoxyethylene sorbitan monolaurate (Tween 20), and sucrose fatty acid ester, sucrose palmitate (Partal, Guerrero, Berjano, Muñoz, & Gallegos, 1994), dioctyl sodium sulfosuccinate (Higuchi, Okada, & Lemberger, 1962) and polyglycerol esters of fatty acids (Tan & Nakajima, 2005) as food emulsifiers. However, the unending demand for more natural products by the consumers and increasing legislations for safe and healthy food by governments has made synthetic emulsifiers in food systems increasingly unpopular. Finding natural emulsifier and stabilizers that have required functionalities in food systems has therefore remained a significant interest (Yang, Leser, Sher, & McClements, 2013) and challenge in food industries.
Development of polyglycerol fatty acid ester-based low-energy nanoemulsion for the improvement of curcumin stability
Published in Journal of Dispersion Science and Technology, 2022
Fangli Chen, Feifei Zhao, Jieying Zhang, Li Yu, Guiju Zhang, Changyao Liu, Nan Wang, Baocai Xu
Polyglycerol fatty acid ester is authorized as a food additive in many countries and regions, which is widely used as an emulsifier in food, cosmetics, medicine, and many other fields.[18,19] In this study, three polyglycerol fatty acid esters were employed to prepare low-energy O/W nanoemulsions, improving the dispersion of curcumin in aqueous solution and protect curcumin from being degraded. The physical properties of the nanoemulsions, such as droplet size, the morphology of oil droplets, zeta potential, and storage stability, were investigated. The chemical stability of curcumin in the nanoemulsions was also studied.