Free Fatty Acid Content Research Articles

Changes in the quality of oil extracted by hot pressing from black cumin (Nigella sativa) seeds and by solvent from the obtained cake during refining.

In this study, oil was extracted from black cumin (Nigella sativa) seed (BCS) by press, and oil was extracted from the obtained cake with a solvent. The changes in the quality of both crude oils obtained by pressing and by solvent were investigated during refining. Findings revealed that the p-anisidin value (p-AV) and fatty acid profile did not change significantly, but there were significant differences (p < .05) in the peroxide value (PV), reflective index, pigment contents, free fatty acid content (FFA%), and antioxidant activity (total phenol content (TPC), thymoquinone, and DPPH inhibition) of BCS oils obtained by the two different methods. PV and FFA decreased to less than 15 meqO2/kg and 0.3%, respectively, in the refined oil. The TPC (65%), thymoquinone (45-97%), carotenoids (86-89%), and chlorophyll (75-85%) were removed from BCS oil, but the DPPH value was raised by about 33%. The current study gives a clear picture of the changes during refining in BCS oil, which can be a useful guide in food applications.

Advances in free fatty acid profiles in gestational diabetes mellitus.

The morbidity of gestational diabetes mellitus (GDM) is increasing and is associated with adverse perinatal outcomes and long-term maternal and infant health. The exact mechanism underlying changes in plasma free fatty acid (FFA) profiles in patients with GDM is unknown. However, it is believed that changes in diet and lipid metabolism may play a role. Fatty acids contain many specific FFAs, and the type of FFA has different impacts on physiological processes; hence, determining changes in FFAs in individual plasma is essential. Alterations in FFA concentration or profile may facilitate insulin resistance. Additionally, some FFAs show potential to predict GDM in early pregnancy and are strongly associated with the growth and development of the fetus and occurrence of macrosomia. Here, we aimed to review changes in FFAs in women with GDM and discuss the relationship of FFAs with GDM incidence and adverse outcomes.

Zno Loaded Singgora Roof Tiles as Heterogeneous Catalyst for Waste Cooking Oil Biodiesel

This study aimed to utilize the waste cooking oil (WCO) into biodiesel using a novel waste Singgora roof tiles wet impregnated with zinc oxide (ZnO) as a heterogeneous catalyst. The motivation behind this choice stems from the non-recyclable nature of Singgora roof tiles and their potential applicability in biodiesel synthesis. The catalyst was characterized by X-ray Fluorescence (XRF) and scanning electron microscopy (SEM) with energy-dispersive X-ray diffractometer (EDX). A two-step transesterification method was employed to reduce the concentration of free fatty acids (FFA) in the WCO. The process started by treating the WCO with sulfuric acid (H2SO4) to diminish the levels of free fatty acid (FFA), followed by the utilization of the Singgora roof tiles catalyst in the subsequent step. A maximum yield of 96.96% biodiesel was obtained under the optimal conditions, which included a methanol-to- oil ratio of 12:1, a catalyst concentration of 1 wt.%, a reaction temperature of 65 °C, and a 2-hour reaction time. The quality of the biodiesel produced was analyzed according to biodiesel standards specified in the ASTM D6751, EN 14214, and AOCS, and were within the ranges. The study demonstrates the potential of using Singgora roof tiles as a heterogeneous catalyst in biodiesel production, offering a promising approach to repurposing non-recyclable materials and advancing sustainable biodiesel production methods.

The Effect of Variation of Palm Fronds Absorbent Concentration In Adsorption Process to Reduce Free Fatty Acid Content on Tengkawang Oil

Tengkawang oil that hasn’t through purification process contains free fatty acid that can affect its quality, where this essence is the polluter that must be removed because it can caused a rancid. The removal of free fatty acid content on Tengkawang oil was done through adsorption process utilizing palm fronds adsorbent by using its cellulose content. Palm fronds went through dilegnification process using 10% of NaOH, then adsorption process was conducted with adsorbent concentration variety 5, 10, 15, 20 and 25%. Adsorbent characterized by utilizing FTIR and SAA, from FTIR result shows that palm fronds contain berlignocellulose function cluster, after delignification the C=C lignin compound function cluster still can be found on FTIR result and after adsorption O-H cluster went through intensity decrement which shows that cellulose content and hydroxyl (-OH) cluster reacted with adsorbat. Furthermore, there’s absorption on C-H function cluster that indicates the existence of free fatty acid compound and other polluter that adsorbed by palm fronds adsorbent. The characteristic of palm fronds adsorbent after delignification process was conducted shows the pore size is on micropore range with surface area of 6.480 m2/g, pore volume of 0.01138 cc/g and pore radius of 12.4 Å. The result of the research shows decreasing percentage of free fatty acid, capacity value and adsorption effectiveness of Tengkawang oil that the highest is on adsorbent concentration as much as 25% with decreasing percentage of free fatty acid as much as 4.68%, adsorption capacity as much as 207.19 mg/g and adsorption effectiveness as much as 36.28%. Keywords: adsorption; delignification; free fatty acid; tengkawang oil

Maximizing the potential of commercial zinc stearate for one-pot esterification and transesterification for high-acidity biodiesel production

Meeting the growing demand for energy while combating the adverse effects of global warming remains challenging today, and biodiesel offers a potential solution to help mitigate the impact of global warming. In this scenario, our primary goal was to optimize biodiesel production from highly acidic soybean oil using a one-pot esterification and transesterification process, addressing the challenges associated with high-acidity substrates. To start, X-ray Diffraction (XRD) guaranteed us just one phase for each commercial catalyst, and we conducted catalytic experiments to select the most suitable Zn-based material for the process, choosing zinc stearate (ZnSt2) as the best candidate. Our study demonstrated that a nano-sized zinc oxide (ZnO) catalyst, which was anticipated to be the most suitable choice, did not exhibit optimal performance. Subsequently, a Full Factorial Design of Experiments (DOE) was employed to optimize reaction parameters, specifically, the reaction temperature and the oil-to-methanol (O:M) molar ratio. The results consistently showed that increased O:M ratio and temperature promoted enhanced fatty acid methyl esters (FAME) production and reduced acidity. Then, experiments were conducted to maximize FAME production and minimize free fatty acid (FFA) content. The results showed that increasing the catalyst concentration from 5 wt% to 10 wt% did not significantly impact FAME production or acidity reduction. Also, while increased methanol should theoretically enhance FAME production and reduce acidity, the results were inconsistent across all experiments. Excess methanol interfered with glycerol separation, leading to decreased FAME yield. Thus, this study underscores the complexity of biodiesel production and highlights the importance of selecting suitable catalysts and optimizing process parameters.

Optimization and synthesis process of biodiesel production from coconut oil using central composite rotatable design of response surface methodology

In the transportation and power production industries, the use of renewable and environmentally friendly fuels has grown in importance. Biodiesel derived from coconut oil contains over 90% saturated fatty acids. Biodiesel was made using alkaline transesterification since coconut oil has a free fatty acid content of less than 2.5%. Enzymatic or chemical transesterification are both possible. For the synthesis of coconut biodiesel, the optimal processing conditions are 60 °C for 1 h, a 6:1 ratio, 1% potassium hydroxide and a 95% yield. According to the experiment, 55 °C was the ideal reaction temperature for using coconut oil to produce biodiesel. Sixty minutes was the ideal amount of time to extract biodiesel from coconut oil. The methanol-to-oil molar ratio raised yield from 6:1 to 8:1, a 95% increase. Significant amounts of an alkaline catalyst, which allows soap to develop under the influence of fatty acids, are responsible for the high yield response; it is concluded that 1 wt% would be an appropriate catalyst concentration for the present investigation. The central composite rotatable design (CCRD) of the response surface methodology method is used to optimize several process parameters, including temperature, reaction duration, methanol-to-oil ratio and catalyst concentration. The CCRD optimization approach produced better results. The following are the final, optimized results: coconut oil methyl ester ratio: 96.69%, temperature: 55 °C; duration: 59.2 min; catalyst concentration: 0.7; molar ratio: 6.4.

Effect of mass and size husk ash adsorbent on acid number and free fatty acid of virgin coconut oil (vco) produced by enzymatic process

Virgin Coconut Oil (VCO) is an oil produced using low temperatures. Efforts to maintain and improve the quality of VCO with papain enzymatic manufacturing method followed by the provision of husk ash adsorbent. The use of papain enzyme as much as 1.5% w/v with an incubation temperature of 40°C 24 hours was effective in reducing acid numbers. The husk ash adsorbent which was treated in an oven at 120°C 2 hours was effective in improving the color quality of the VCO. Variations of husk ash were adsorbent size (60, 80, and 100) mesh and mass (15, 20, and 25) grams. The sample that has been mixed with adsorbent is stirred with a magnetic stirrer at 300 rpm 1 hour then separated by centrifuge at 1000 rpm 1 hour and ends with VCO filtering with filter paper to separate the remaining adsorbent from the oil. Samples were tested for acid number and free fatty acid content. The results show that the smaller the size of the adsorbent and the more the amount added gives a positive effect on decreasing the acid number and free fatty acid content. Production of VCO has low environmental impact because it uses low energy.

Improving the quality properties of soybean oil by using rice bran oil.

This study aims to study the effect of substituting soybean oil (SO) with rice bran oil (RBO) at different levels (25%, 50%, and 75%) on the physical and chemical properties, fatty acid composition, and oxidative stability of SO, also, study the effect of storing SO, RBO, and their blend oils at ambient temperature for a period of 12 months on the content of free fatty acids (% FFA), peroxide value (PV), and thiobarbituric acid (TBA). RBO demonstrated good quality, as evidenced by its initial low values of % FFA, PV, and TBA. Furthermore, RBO was found to be an excellent source of γ-oryzanol, whereas the other oils lacked this compound. Consequently, increasing the proportion of RBO in SO resulted in the least degradation, while pure SO exhibited the highest degree of degradation. Moreover, the blend oils demonstrated an inhibitory effect against oxidation, allowing for a prolonged storage period without the use of industrial antioxidants. Throughout the entire storage period, the % FFA and PV of all tested blend oil samples remained within the limits recommended for human consumption. TBA exhibited a similar trend to PV. However, an incremental increase in TBA values was observed as the storage period of the oils extended. In SO, TBA levels increased from 0.533 mg malonaldehyde/kg oil at the beginning to 1.446 mg malonaldehyde/kg oil after 12 months of storage. In RBO, TBA levels increased from 0.336 mg malonaldehyde/kg oil at the beginning to 0.882 mg malonaldehyde/kg oil after 12 months of storage.

Innovation in producing virgin coconut oil without heating in Pekon Bumiratu, Pringsewu

Among the various potential gardens in Pekon Bumiratu, Pagelaran District, Pringsewu Regency, coconut plants stand out. However, the processing of coconut produce by farmers is suboptimal, as the coconut yield is typically consumed or sold without undergoing processing. This is primarily due to the limited knowledge and skills of local farmers regarding coconut processing and its derivatives. This activity aims to enhance the knowledge and skills of coconut farmers in processing coconuts into Virgin Coconut Oil (VCO) using a non-heating method. The activities involved a combination of lecture methods and practical demonstrations. The VCO produced during the activities underwent laboratory analysis to assess its quality. The results of the activity indicate a significant increase in understanding by 61.6%. This suggests a substantial improvement in public knowledge regarding the processing of coconuts into VCO. Laboratory analysis of the VCO produced by the participants revealed a water content of 0.18%, an iodine value of 8,150 g iod/100g, a free fatty acid content of 0.17%, and a peroxide value of 1.32 mg/Kg Ek. These results align with the quality standards outlined in SNI 7381-2008 for VCO.

Influence of Physical and Chemical Activation of Coconut Shell Applied to Reduce Free Fatty Acids of Used Cooking Oil in Biodiesel Plant

This research was conducted to compare the characteristics of activated carbon that synthesized via different methods, physical and chemical activation. It was applied to reduce Free Fatty Acids (FFA) in used cooking oil which will be used in the manufacture of biodiesel. Physical activation was carried out by heating dried coconut shell in a tube furnace at 900°C in N2 gas flowing, by varied the holding time; 2 hours, 3 hours, and 4 hours. Meanwhile, chemical activation was conducted using phosphoric acid solution with various concentrations: 9%, 10%, and 11%. The BET (Brunauer-Emmett-Teller) test was processed to determine the surface area of ​​the activated carbon. The FFA test was conducted to determine the FFA content in treated used cooking oil. The activated carbon with chemical activation has a surface area of ​​260.57 m2/gram, 323.55 m2/gram, and 162.21 m2/gram at concentrations of phosphoric acid 9%, 10%, and 11%, respectively. Meanwhile, for physical activation, the surface area were 278.58 m2/gram, 448.368 m2/gram, and 444.74 m2/gram with variations in heating holding time of 2 hours, 3 hours, and 4 hours, respectively. The lowest levels of FFA are found in cooking oil with a phosphoric acid concentration of 11%, which is 1.505%. The higher the concentration of chemical activator, the greater the adsorption power of an activated carbon. The lowest levels of fatty acids are found in cooking oil with a holding time of 4 hours, which is 1.805%. FFA (Free Faty Acid) test results show that the longer the heating holding time, the better the activated carbon will be.

Chemical Profiling and Industrial Viability of Neem Seed Oil: A Comprehensive Study for Sustainable Biodiesel Production

The study explores the chemical composition of neem seed oil, highlighting its potential for commercial biodiesel production and various industrial applications. The oil, with a liquid state, pale greenish-yellow color, and pleasant odor, yielded 32.1%, surpassing industrially extracted oils like soybean and cottonseed. Factors influencing its composition include seasonal variations, geographical origin, genetic disparities, growth stages, plant segments, and postharvest processing. Despite these, neem seeds meet the required oil content percentage for large-scale industrial biodiesel production. However, challenges like high free fatty acid content and elevated acid values necessitate acid esterification before alkaline transesterification, potentially increasing production costs. The study also highlights the importance of appropriate seed processing practices to optimize oil yield and quality.

Effects of antioxidant-rich Lactiplantibacillus plantarum inoculated alfalfa silage on rumen fermentation, antioxidant and immunity status, and mammary gland gene expression in dairy goats

BackgroundMilk synthesis in lactating animals demands high energy metabolism, which results in an increased production of reactive oxygen metabolites (ROM) causing an imbalance between oxidants and antioxidants thereby inducing oxidative stress (OS) on the animals. To mitigate OS and postpartum disorders in dairy goats and gain insight into the impact of dietary choices on redox status during lactation, a feeding trial was conducted using alfalfa silage inoculated with a high-antioxidant strain of Lactiplantibacillus plantarum.MethodsTwenty-four Guanzhong dairy goats (38.1 ± 1.20 kg) were randomly assigned to two dietary treatments: one containing silage inoculated with L. plantarum MTD/1 (RSMTD-1), and the other containing silage inoculated with high antioxidant activity L. plantarum 24-7 (ES24-7).ResultsES24-7-inoculated silage exhibited better fermentation quality and antioxidant activity compared to RSMTD-1. The ES24-7 diet elevated the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in milk, serum, and feces of lactating goats (with the exception of T-AOC in milk). Additionally, the diet containing ES24-7 inoculated silage enhanced casein yield, milk free fatty acid (FFA) content, and vitamin A level in the goats’ milk. Furthermore, an increase of immunoglobulin (Ig)A, IgG, IgM, interleukin (IL)-4, and IL-10 concentrations were observed, coupled with a reduction in IL-1β, IL-2, IL-6, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α concentrations in the serum of lactating goats fed ES24-7. Higher concentrations of total volatile fatty acid (VFA), acetate, and propionate were observed in the rumen fluid of dairy goats fed ES24-7 inoculated silage. Moreover, the diet containing ES24-7 inoculated silage significantly upregulated the expression of nuclear factor erythroid 2 like 2 (NFE2L2), beta-carotene oxygenase 1 (BCO1), SOD1, SOD2, SOD3, GPX2, CAT, glutathione-disulfide reductase (GSR), and heme oxygenase 1 (HMOX1) genes in the mammary gland, while decreased the levels of NADPH oxidase 4 (NOX4), TNF, and interferon gamma (IFNG).ConclusionsThese findings indicated that feeding L. plantarum 24-7 inoculated alfalfa silage not only improved rumen fermentation and milk quality in lactating dairy goats but also boosted their immunity and antioxidant status by modulating the expression of several genes related to antioxidant and inflammation in the mammary gland.

Pengaruh Suhu Pemanasan terhadap Karakteristik Mutu Minyak Goreng Bekas Pakai Pedagang Gorengan

Palm cooking oil has been widely used in food processing because it is easily available at a relatively low price in the market. People's habit of repeatedly using cooking oil is considered more economical and can save household costs, but this can be a bad risk to health. This is because repeated use at high temperatures will reduce the quality of cooking oil. This study aimed to determine the effect of heating temperature on the quality of cooking oil used by fried traders in terms of color analysis, free fatty acids, iodine number, and peroxide value. This study used a completely randomized design with heating temperature treatment (150°, 180°, and 210°C) on cooking oil used by fried peddlers, which was repeated two times trial repetition. The results showed that heating temperature significantly increased the redness, free fatty acid content, and peroxide value of used cooking oil. However, the heating temperature significantly reduced the iodine value in used cooking oil. Based on SNI 7709:2019, cooking oil used by fried traders who were given different heating treatments did not meet the quality requirements for cooking oil in term of its free fatty acid content and color quality.

Fatty Acid Elongase Gene PcELO7 is Essential for Lipid Accumulation and Fecundity of Panonychus citri (Acari: Tetranychidae).

RNA interference (RNAi) has been proposed as a promising strategy for sustainable and ecofriendly pest control. The insect cuticle lipids were deposited on the body surface and functioned as a defense against chemical xenobiotics. They consisted of aliphatic compounds, including free fatty acids (FFAs). However, elongase of very long chain fatty acids (ELOs) is essential for FFA biosynthesis; the function of ELO is still unknown in many arthropods, including Panonychus citri (P. citri). In this study, three ELOs were cloned. Developmental-specific mRNA expression results revealed that three PcELOs were highly expressed in egg and adult females. Whereas PcELO7 was dominantly expressed in adult females. Under spirobudiclofen stress, ELOs mRNA expression had different changes, and PcELO7 was down-regulated. The silencing of PcELO7 resulted in a dramatic reduction of oviposition and hatchability. Significant reduction of FFA contents was also examined within PcELO7-repressed P. citri. In addition, we found that PcELO7 mRNA levels were related to fecundity and could affect triacylglycerol (TG) contents. The findings demonstrated that the introduction of dsPcELO7 via oral feeding induced the RNA interference-mediated silencing of a special target gene and could result in mortality and reproduction. In conclusion, PcELO7 is a special RNAi target for P. citri control, and its lethal mechanism might be disturbing lipids biosynthesis.

Pengaruh Penambahan Sodium Lauryl Sulfat terhadap Karakteristik Sabun Padat pada Mata Kuliah Praktikum Analitik Proses

Solid soap as a result from process analysis practicum can be produced using with hot process method using raw material of palm oil and a strong base in the form of NaOH. The aim of this research is that apart from fostering student inquiry regarding the soap making process, they are also able to analyze the parameters of solid soap over a certain period based on variations in the amount of added surfactant. The methods used in practicum activities are dividing practicum groups, making solid soap, and collecting practicum reports. In the activity of making solid soap, the concentration of sodium lauryl sulfate (SLS) was varied for each group, 0, 1, 2 and 3% w/w respectively. The parameters measured in this research were the pH value, water content, ability to form foam, free fatty acid content and ethanol insoluble material in solid soap. The pH characterization of the results of the saponification process shows that soap at all variations in SLS concentration is predominantly alkaline. The characterization carried out showed that the levels of free fatty acids and ethanol insoluble substances met SNI 3532:2016 standards. Water content parameters do not meet these standards because the measurements were carried out during practical activities and without the process of holding the soap product. From the results of observing these parameters, in general it can be concluded that the solid soap products resulting from the practical work have the best quality under the condition of adding SLS with a concentration of 1%.

Lactobacillus paracasei JY062 Alleviates Glucolipid Metabolism Disorders via the Adipoinsular Axis and Gut Microbiota.

Glycolipid metabolic disorders (GLMD) refer to a series of metabolic disorders caused by abnormal processes of glucose and lipid synthesis, decomposition, and absorption in the body, leading to glucose and lipid excess, insulin resistance, and obesity. Probiotic intervention is a new strategy to alleviate metabolic syndrome. Lactobacillus paracasei JY062 (L. paracasei JY062) was separated from the Tibet-fermented dairy products. The results demonstrated a strong ability to relieve blood glucose disorders, blood lipid disorders, and tissue damage. The LPH group had the best effect, significantly decreasing the total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), leptin, insulin, and free fatty acid (FFA) concentrations and increasing the high-density lipoprotein cholesterol, adiponectin, and GLP-1 level compared to HFD-group mice. L. paracasei JY062 could activate the APN-AMPK pathway, increased AdipoQ, AMPK GLUT-4, and PGC-1α mRNA expression and decreased SREBP-1c, ACC, and FAS mRNA expression. L. paracasei JY062 intervention decreased the relative abundance of harmful bacteria, increased the relative abundance of beneficial bacteria, and restored the imbalance of gut microbiota homeostasis caused by a high-glucose-fat diet. L. paracasei JY062 alleviated glucolipid metabolism disorders via the adipoinsular axis and gut microbiota. This study provided a theoretical basis for probiotics to ameliorate glucolipid metabolism disorders by regulating the adipoinsular axis.

Evaluation of Ashwagandha herb to enhance shelf-life of Ghee against oxidative deterioration

Ghee, a crucial component in Indian cuisine, is prone to oxidative rancidity, affecting its shelf- life, flavor and nutritional quality. This research explores the potential of Ashwagandha, a medicinal herb, as a natural antioxidant to enhance Ghee’s oxidative stability. The study involves the collection and preparation of Ashwagandha root, followed by the addition of its aqueous extract to cow cream during the ghee-making process. The herbal Ghee is then evaluated for acceptability based on various sensory parameters. Chemical analyses, including peroxide value, free fatty acid content, radical-scavenging activity using DPPH assay and total phenolic content, are conducted to assess the impact of Ashwagandha on Ghee quality and stability. The results show significant differences in peroxide value and free fatty acid content between control Ghee and Ashwagandhainfused ghee, highlighting the potential antioxidant effects of the herb.The study emphasizes the growing interest in utilizing natural, plant-based antioxidants to address concerns associated with synthetic antioxidants. While the addition of herbal extracts has challenges, such as flavor alteration and solvent residue, exploring alternative sources like Ashwagandha opens avenues for improving food preservation naturally. The findings contribute valuable insights into the potential use of herbs in enhancing the quality and shelf-life of food products.

The association between plasma angiopoietin-like protein 4, glucose and lipid metabolism during pregnancy, placental function, and risk of delivering large-for-gestational-age neonates

BackgroundLarge-for-gestational-age (LGA) neonates have increased risk of adverse pregnancy outcomes and adult metabolic diseases. We aimed to investigate the relationship between plasma angiopoietin-like protein 4 (ANGPTL4), a protein involved in lipid and glucose metabolism during pregnancy, placental function, growth factors, and the risk of LGA. MethodsWe conducted a prospective cohort study and recruited women with singleton pregnancies at the National Taiwan University Hospital between 2013 and 2018. First trimester maternal plasma ANGPTL4 concentrations were measured. ResultsAmong 353 pregnant women recruited, the LGA group had higher first trimester plasma ANGPTL4 concentrations than the appropriate-for-gestational-age group. Plasma ANGPTL4 was associated with hemoglobin A1c, post-load plasma glucose, plasma triglyceride, plasma free fatty acid concentrations, plasma growth hormone variant (GH-V), and birth weight, but was not associated with cord blood growth factors. After adjusting for age, body mass index, hemoglobin A1c, and plasma triglyceride concentrations, plasma ANGPTL4 concentrations were significantly associated with LGA risk, and its predictive performance, as measured by the area under the receiver operating characteristic curve, outperformed traditional risk factors for LGA. ConclusionsPlasma ANGPTL4 is associated with glucose and lipid metabolism during pregnancy, plasma GH-V, and birth weight, and is an early biomarker for predicting the risk of LGA.

Synthesis of Biodiesel from Refined Waste Cooking Oil with Active Natural Zeolite

This research evaluates refining waste cooking oil with active natural zeolite, utilizes it for biodiesel synthesis, and characterizes the synthesized methyl ester. This experimental laboratory research was carried out: (1) activation of natural zeolite, (2) refining waste cooking oil with active natural zeolite, (3) determination of free fatty acid (FFA) content of the oil, (4) transesterification with KOH catalyst, (5) characterization of the synthesized methyl esters according to the SNI 7182:2015, and (6) identification of the methyl ester component by GC-MS. The results showed that the FFA content of the refined waste cooking oil using active natural zeolite with concentrations of 10%, 20%, and 30% per mass of oil were 2.97, 2.0, and 1.56%, respectively. The yield of methyl ester transesterified with various concentrations of KOH (0.8, 1.0, and 2% per mass of oil), respectively, were 80.13, 85.34, and 74.98%. The synthesized methyl ester resulted in the characteristics: 0.867 g/mL of density; 5.72 cSt of viscosity; 1.449 of refractive index; 1.46 g KOH/g of acid number; and 0.023% of water content. Identification of GC-MS obtained the synthesized methyl esters, which include: 46.10% of methyl hexadecanoic, 41.68% of methyl 9-octadecanoic, 6.42% of methyl octadecanoic, and 5.80% of methyl eicosanoic.

High-energy ultrasound improves culture activity, polyunsaturated fatty acids and in-vitro protein digestibility in probiotic yogurt

The effect of ultrasound (US) on viable, bacteria counts, free fatty acid and amino acid content and in vitro protein digestibility of set-type probiotic yogurts produced with fortification of milk proteins (caseinate and whey protein concentrate) or skimmed milk powder (SMP) was investigated. US application increased the protein content of probiotic yogurts and enhanced the growth of yogurt bacteria, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, and the probiotic bacterium, Bifidobacterium animalis subsp. lactis (BB-12), in yogurt samples. All US-treated groups had higher probiotic counts between 8.44 and 8.61 log cfu/g than their counterpart controls at the end of storage. One- or two- stage US application reduced the saturated fatty acids (SFA) ratio by up to 19% and increased the polyunsaturated fatty acids (PUFA) ratio of probiotic yogurts by up to 40%. At the beginning and end of storage, one-stage US applied Y2 and YP2 groups had the highest PUFA ratio as 36.86, 33.25 and 25.10, 20.03%, respectively, but it did not affect the monounsaturated fatty acids (MUFA) ratio. It also positively affected the in vitro protein digestibility, and total amino acid amounts of probiotic yogurts in pre- and post-digestion. The soluble protein ratios of all US-treated samples were higher both at the beginning and end of storage. Industrial relevanceUltrasound is a promising approach in dairy technology. The results obtained in this study can help to improve the probiotic viability, antioxidant capacity, PUFA content, and digestibility of proteins in dairy products by US treatment and provide an opportunity for US-treated dairy products in the functional food market. Ultrasound is a so- called green technology because it is environmentally friendly, and the use of ultrasound in production will positively affect consumer preferences. In addition, obtained data may be beneficial for the industrial use of this technology.