Investigating the influence of pinhão manso (Jatropha curcas) seed endocarp on the acidity index of the extracted oil

Biodiesel is a clean and cyclical energy resource that is derived from animal and/or vegetable fat. As it blends well with petrodiesel, biodiesel is added to Brazilian commercial diesel. The main raw materials used to produce biodiesel in Brazil include soybean, corn, and sunflower oils. However, these are also used for human consumption and hence, have a high market value. Therefore, pinhão manso oil, which exhibits high productivity at low cost, is a promising alternative. However, the high acidity index of this oil results in a low transesterification yield and the produced biofuel does not meet the requirements imposed by the ANP. Thus, this study intends to demonstrate that a large part of the free fatty acids in pinion oil are present in the seed endocarp. For the development of the project, the oil was extracted by hot solvent, using the soxhlet equipment and the hexane solvent, to determine the acidity index, the titration technique was used, the titrant used was sodium hydroxide. So the acidity index of the oil extracted from the seed with its shell is 10.9 mgKOH/g, while the lipid obtained without the shell exhibits a value of 0.95 mgKOH/g, proving the influence of the endocarp.

Extraction, characterization, and optimization of biodiesel production from Pachira aquatica Aubl

Given the great energy demand to meet the needs of modern society, it is essential that new alternatives to replace fossil diesel are studied. And biodiesel is an alternative that has been gaining prominence on the world stage, mainly with the use of vegetable oils with a high lipid content, such as Pachira aquatica Aubl, also known as munguba. Given the above, the objective of this work was to extract the oil from the seeds of Pachira aquatica, evaluate the physicochemical characteristics of the oil and define the best conditions for catalytic mixing with temperature variation in the production of biodiesel from the oil obtained. Thus, the acidity index, saponification, refraction, peroxide, water content and fatty acid profile of the oil were evaluated. Fourteen treatments of biodiesel produced with different amounts of sulfuric acid and temperature were evaluated. They were analyzed for water content, specific mass, kinematic viscosity at 40 ºC, refractive index and ester content. It was found that the lipid content of Pachira aquatica seeds was 42.19% and its physical chemistry analysis showed that it can be used in the production of biofuels. There was a greater presence of saturated fatty acids, with a predominance of palmitic acid with 81.95%. Biodiesel produced from oil, on the other hand, showed higher production of esters in relation to the volume used at temperatures of 60 ºC and 0.6 mL of sulfuric acid, and that its properties showed that the plant can be a possible alternative for the production of biodiesel.

Quality control of butter

The most common problem among ready-made foods is the adulteration of butter, which is replaced by margarine or vegetable spreads. Milk and other dairy products made from raw milk are not left out. The production and sale of low-quality, counterfeit products poses a direct threat to human health and affects the competitive environment among producers. As a result of research, it should be noted that the raw milk market is not fully saturated, so improving the quality of cream production and processing of milk products, namely butter, competition for suppliers, microbiological improvements, as well as improvements to plants and systems – remains relevant. During the analysis, some physicochemical parameters of butter were studied, namely: acidity of the fat phase, mass fraction of moisture and fat. The acidity index was within the norm, although it differed in all samples: the lowest was found in sample № 1 (1.1 °K), and the highest was in sample № 2 (1.6 °K). As for such an indicator as the content of table salt and the content of fat and pH of plasma, the oils Sweet cream “Selyanske”, 72,6 % TM “Svoya Liniya”, Sweet cream, 73.0 % LLC “Eney”, “Poltavske”, 62.5 % LLC “Techmolprom” do not meet the requirements of DSTU 4399:2005. The mass fraction of fat in butter brands PJSC “Dubnomoloko” and “Pryvat-Fud” – was lower than indicated on the package, by 1.4 % and 2.6 %, respectively, and brands “Svoya Liniya”, LLC “Eney” and Techmolprom LLC on the contrary – by 18.0 %, 18.4 % and 12.5 % more. According to the results of microbiological studies, it was found that the number of mesophilic aerobic and facultatively anaerobic microorganisms, yeasts, fungi and bacteria of the Escherichia coli group in the studied samples of butter of all brands does not exceed the permissible norms. This fact testifies to the relative “purity” of the raw material from which the butter was made, as well as to the observance of veterinary and sanitary and hygienic norms during the production and storage of butter. Summing up the research, it should be noted that, despite the identified physical and chemical shortcomings of all samples of butter, preference should be given to sour cream butter “Selyanske”, 73.0 % of PJSC “Dubnomoloko” and “Selyanske” sweet cream, 73.0 % “Privat- Fud”, as none of them exceeded such indicators as fat content and plasma pH of oil, which may indicate the absence of impurities in vegetable fats in this product.

Synthesis of Biodiesel by Transesterification Reaction from Jatropha Curcas Lineu Oil Seed (“Mpuluka”) Collected in City of Uíge, Angola

In this work, it was made a study of biodiesel synthesis by transesterification reaction from Jatropha Curcas Lineu Oil (“Mpuluka”) with methanol in the presence of NaOH. First of all a seed treatment and a granulometric study were carried out and it was concluded that the oil content and yield obtained from the extraction do not depend on the particles size of the seed. The Jatropha Curcas oil was obtained by means of a Soxhlet extraction system, using n -hexane. The oil content obtained was 45,32% and its yield was 90,88%. The physicochemical properties analysis of the oil indicates a high acidity index. For this, the synthesis of biodiesel was carried out using two steps: pre-treatment of crude oil before transesterification reaction and the esterification of crude oil followed by transesterification. The best yield in biodiesel (≈60%) was obtained with the molar ratio (oil/alcohol):1/6. The biodiesel obtained falls within admissible limit values of the international quality standards defined by ASTM_D and EN / ISO. In this work, it was made a study of biodiesel synthesis by transesterification reaction from Jatropha Curcas Lineu Oil (“Mpuluka”) with methanol in the presence of NaOH. First of all a seed treatment and a granulometric study were carried out and it was concluded that the oil content and yield obtained from the extraction do not depend on the particles size of the seed. The Jatropha Curcas oil was obtained by means of a Soxhlet extraction system, using n -hexane. The oil content obtained was 45,32% and its yield was 90,88%. The physicochemical properties analysis of the oil indicates a high acidity index. For this, the synthesis of biodiesel was carried out using two steps: pre-treatment of crude oil before transesterification reaction and the esterification of crude oil followed by transesterification. The best yield in biodiesel (≈60%) was obtained with the molar ratio (oil/alcohol):1/6. The biodiesel obtained falls within admissible limit values of the international quality standards defined by ASTM_D and EN / ISO.

São os azeites de oliva mais instáveis que os óleos vegetais frente ao aquecimento? Um estudo comparativo

Resumo A procura por alimentos saudáveis está crescendo e os azeites vêm ganhando atenção. Entretanto, ainda não há consenso no que se refere às melhores formas de sua utilização na culinária. O objetivo desse estudo foi avaliar as possíveis modificações físico-químicas decorrentes do aquecimento em azeites de oliva em comparação a outros óleos vegetais. Amostras de azeites de oliva extravirgem (AOE) ou refinado tipo único (AOU); óleo de canola (OC) e óleo de soja (OS) foram selecionadas considerando as marcas mais procuradas pela população. Essas foram aquecidas a 40, 70, 120 e 180°C e analisadas quanto à rancificação hidrolítica (índice de acidez) e oxidativa (níveis de malondialdeído - MDA). Os resultados mostraram que o aquecimento foi capaz de alterar a disponibilidade de ácidos graxos livres em AOE e AOU (redução de cerca de 30 % no índice de acidez em relação à temperatura ambiente) em comparação à OC e OS. Alterações nesse parâmetro não foram observadas para os óleos. Quanto aos níveis de MDA, observou-se que tanto o AOE quanto o AOU são menos suscetíveis à termoxidação quando aquecidos, em comparação às amostras OC/OS, que apresentaram índices estatisticamente superiores. Quando comparados em conjunto, observou-se o seguinte comportamento para os níveis de acidez (AOE = AOU > OC = OS) e MDA (OS > OC > AOU = AOE). Os dados obtidos no presente estudo indicam uma maior aplicabilidade dos azeites de oliva em preparações aquecidas, no entanto, futuros estudos são necessários para melhor compreender as reações químicas envolvidas nos processos de termoproteção desses. Palavras-chave: Ácidos graxos; estabilidade; rancificação; antioxidantes. Abstract Are olive oils more unstable than vegetable oils on heating? A comparative study Demand for healthy foods is growing and olive oils are gaining attention. However, there is still no consensus regarding the best ways to use it in cooking. This study aimed to evaluate the possible physicochemical modifications resulting from heating olive oil compared to vegetable oils. Samples of extra virgin (AOE) or refined type (AOU) olive oils; canola oil (OC) and soybean oil (OS) were selected considering the most consumed brands by the population. Samples were heated at 40, 70, 120, and 180 ° C and analyzed for hydrolytic (acidity index) and oxidative (malondialdehyde - MDA) rancidity. The results showed that heating was able to alter the availability of free fatty acids in AOE and AOU (about 30 % reduction in acidity index compared to room temperature) in relation to OC and OS. Changes in this parameter were not observed for oils. Regarding MDA levels, it was observed that both of which olive oils were less susceptible to thermo-oxidation when heated compared to OC or OS, which showed statistically higher rates. When compared together, the following behavior was observed for acidity levels (AOE = AOU> OC = OS) and MDA (OS> OC> AOU = AOE). The data obtained in the present study indicate greater applicability of olive oils in heated preparations, however, further studies are needed to better understand the chemical reactions involved in their thermoprotection processes. Keywords: Fatty acids; stability; rancification; antioxidants. Resumen ¿Son los aceites de oliva más inestables que los aceites vegetales al calentarlos? Un estudio comparativo La demanda de alimentos saludables es grande y los aceites de oliva están ganando atención. Todavía, no hay consenso sobre las mejores formas de utilizarlo en la cocina. El objetivo de este estudio fue evaluar los posibles cambios físicos y químicos derivados del calentamiento de los aceites de oliva en comparación con otros aceites vegetales. Muestras de aceite de oliva virgen extra (AOE) o refinado de tipo único (AOU); aceite de canola (OC) y aceite de soja (OS) fueron seleccionados considerando las marcas más buscadas por la población. Estos fueron calentados a 40, 70, 120 y 180 ° C y analizados para rancificación hidrolítica (índice de acidez) y oxidativa (malondialdehído - MDA). Los resultados mostraron que el calentamiento puede alterar la disponibilidad de ácidos grasos libres en AOE y AOU (reducción de aproximadamente 30% en el índice de acidez en relación a la temperatura ambiente) en comparación con OC y OS. No se observaron cambios en este parámetro para los aceites. Para los niveles de MDA, se observó que tanto AOE como AOU son menos susceptibles a la termoxidación cuando se calientan, en comparación con las muestras de OC / OS, que mostraron tasas estadísticamente más altas. Cuando se compararon juntos, se observó el siguiente comportamiento para los niveles de acidez (AOE = AOU> OC = OS) y MDA (OS> OC> AOU = AOE). Los datos obtenidos en el presente estudio indican una mayor aplicabilidad de los aceites de oliva en preparaciones calentadas, sin embargo, son necesarios futuros estudios para comprender mejor las reacciones químicas involucradas en sus procesos de termoprotección. Palabras clave: Ácidos grasos; estabilidad; rancificación; antioxidantes.

Physicochemical Profile of Essential Oils Obtained from Chia (Salvia hispanica L.) Seeds Grown in Different Agro-Ecological Zones of Kenya

The chia seed samples were purchased from farmers in five locations in three agro-ecological zones in Kenya. The oil was obtained by cold pressing and physicochemical properties were determined; the fatty acid profile was determined by Gas chromatography. The mean oil yield from pressing was 16%, the refractive index of chia seed oil at 25 °C ranged from 1.4811 to 1.4832, specific gravity ranged from 0.9616 to 0.9629, acidity index and free fatty acids content ranged from 0.0345-0.0808 mg KOH/g oil, and 0.1736-0.4061%, respectively. The matter in volatiles ranged from 0.047-0.086%. The saponification value ranged from 162.1969–183.3791 milligrams (mg) of potassium hydroxide (KOH) per gram (g) of chia seed oil. The differences in refractive index, acidity index, free fatty acids, specific gravity, and saponification value, were statistically significant at (P<0.05). The α-linolenic (C18:3) and linoleic acids (C18:2) were the dominant fatty acids in chia seed oil and they varied with regions. The levels α-linolenic (C18:3) and linoleic acids (C18:2) ranged from 53.32-64.04% and 19.37-22.87%, respectively. The levels of oleic, linoleic, and linolenic fatty acids in chia seed oils from different regions were statistically significant at (P<0.05). The study recommended the cultivation of chia seed in agro-ecological zones II and III where higher yields and higher content of linoleic and linolenic fatty acids were reported, consumption of chia seed oil as edible oil, and substitution of marine oils with chia oil as potential sources of polyunsaturated fatty acids.

Influence of the Breed of Sheep on the Characteristics of Zamorano Cheese

This work aimed to study the effects of using ewe’s milk from Churra, Assaf, or both breeds on the physicochemical and sensory characteristics of Zamorano cheese at the end of ripening. Zamorano cheese is a hard variety with protected designation of origin (PDO) produced in the province of Zamora (Spain) with raw or pasteurized ewe’s milk. Five batches of Zamorano cheese were produced with pasteurized ewe’s milk. One batch was elaborated using milk from the Churra breed, the other using milk from the Assaf breed, and the remaining three employed milk mixtures of Churra and Assaf breeds in the proportions 75:25, 50:50 and, 25:75, respectively. Cheeses made with a higher proportion of Churra milk showed a predominance of hydrophilic peptides, while hydrophobic peptides predominated in cheeses with a greater percentage of milk from the Assaf breed. The largest content of most free amino acids was found in cheeses produced with the highest percentage of Churra milk. These cheeses presented the highest values for fat acidity index and free fatty acids content and showed greater elasticity and adhesiveness, as well as lower granularity and hardness. In the sensory evaluation, aftertaste and persistence were higher in these cheeses, being scored with the best overall values.

Acidity Reduction of Bio-Oil by Methylic Esterification Reactions

An alternative to fossil fuels is the use of triglyceride biomass for conversion to biofuel by the thermal cracking process, also known as pyrolysis. The liquid phase, called bio-oil, has physicochemical properties like petroleum-derived fuels. One of the undesirable characteristics of bio-oil is the high acidity index, due to the presence of short-chain carboxylic acids in its composition. This feature makes refining and use inviable. The objective of this work was to perform esterification reactions using bio-oil, produced from soybean oil pyrolysis already characterized, in order to reduce its acidity index. Besides that, the esterified bio-oil was submitted to different washing experiments to decrease even more the final acidity. For the esterification reaction 25 g of bio-oil was used at a temperature of 64 °C, using from 0.8 to 2.2% sulfuric acid and 0.5 to 99.5% mass ratio of methyl alcohol and bio-oil. The highest acidity index reduction after 20 min was 81.2%, the esterified bio-oil reduced from 129 to 32.4 mg KOH g-1. Esterification reaction followed by washing and neutralization can decrease even more those values and, the acidity index can reach zero.

Acidity Reduction of Bio-Oil by Methylic Esterification Reactions

An alternative to fossil fuels is the use of triglyceride biomass for conversion to biofuel by the thermal cracking process, also known as pyrolysis. The liquid phase, called bio-oil, has physicochemical properties like petroleum-derived fuels. One of the undesirable characteristics of bio-oil is the high acidity index, due to the presence of short-chain carboxylic acids in its composition. This feature makes refining and use inviable. The objective of this work was to perform esterification reactions using bio-oil, produced from soybean oil pyrolysis already characterized, in order to reduce its acidity index. Besides that, the esterified bio-oil was submitted to different washing experiments to decrease even more the final acidity. For the esterification reaction 25 g of bio-oil was used at a temperature of 64 °C, using from 0.8 to 2.2% sulfuric acid and 0.5 to 99.5% mass ratio of methyl alcohol and bio-oil. The highest acidity index reduction after 20 min was 81.2%, the esterified bio-oil reduced from 129 to 32.4 mg KOH g-1. Esterification reaction followed by washing and neutralization can decrease even more those values and, the acidity index can reach zero.