This study describes the validation of a headspace gas chromatography with flame ionization (HS-GC-FID) method for the determination of propanal, pentanal, hexanal, octanal, and trans-2-nonenal originated by lipid oxidation from cat food samples, as well as the evaluation of the matrix effect in the results. This method was applied to the analysis of commercial cat food and proved to be suitable for the determination of these volatile compounds in different samples. Mean recoveries between 88 and 109% were obtained and repeatability expressed as relative standard deviation was always lower than 6.95%. The intra- and inter-assay precisions ranged from 0.44 to 20.88% and from 0.45 to 20.52%, respectively. In addition, the matrix effect of cat food samples was determined by comparing the slopes of the standard addition method, and the external calibration curve and its influences were verified. These results highlight the high potential of this method, which allows the determination of lipid oxidation products in cat food samples directly, without requiring prior sample preparation techniques.

The objective of this study was to evaluate the effect of pasteurization, lyophilization and spray-drying on the lipid profile of donated human milk (DHM) at different lactation stages. Nine frozen samples of colostrum, transitional and raw mature human milk (HM) were collected from the Human Milk Bank (HMB) of the Hospital Universitário de Maringá (HUM). Samples were thawed and pooled according to lactation stage. Thereafter, it was submitted to pasteurization, lyophilization and spray-drying processes and later the fatty acid (FA) composition and the lipid profile analyses were performed. Gas chromatograph (GC) with flame ionization detector (FID) and electrospray ionization (ESI) mass spectrometer (MS) were used, respectively. In the FA composition analysis, it was observed that the same classes of saturated FA (SFA), monounsaturated FA (MUFA) and polyunsaturated FA (PUFA) were preserved throughout the process and in all lactation stages. The lipid profiles were also preserved after processing. Therefore, the lyophilization and spray-drying processes are promising techniques to preserve the DHM in the HMB, once the components evaluated were preserved, and both techniques facilitate the transport and storage, as the techniques reduce the sample volume.

Sunflower oil has several properties that are valuable to the human skin and health; however, they are target of adulterations. In this study, in order to evaluate the authenticity of edible and cosmetics based on sunflower oils, the triacylglycerol (TAG) profiles using direct infusion electrospray ionization mass spectrometry (ESI-MS), the fatty acid (FA) composition by gas chromatography with flame ionization detection (GC-FID) and principal component analysis, of seven commercial samples were determined and the results obtained were compared with the pure sunflower and soybean oils. Of the seven brands analyzed, just one sample presented only sunflower oil in its composition; two stated in the label soybean addition; and four did not present the real composition of the product in the label. Therefore, GC-FID and ESI-MS analysis in conjunction with principal component analysis (PCA) demonstrated that they are complementary techniques and could be applied in food industries to assess the quality of vegetable oils, since results showed the need for stricter quality control for this product.

Acerola is a tropical fruit with a large industrial and commercial appeal due to its organoleptic qualities and bioactive compound-rich nature. Thus, as bioactive compounds (BC) stability is of great interest in the food industry, assessment of preserving techniques to prolong shelf life has become imperative. Hence, the purpose of this study was to evaluate how storage affects BC conservation in microencapsulated and lyophilized acerola pulps over 180 days. For this matter, antioxidant tests, physical-chemical analyzes, and vitamin C analysis by mass spectrometry were performed. Results indicated that microencapsulation better preserved the antioxidants in acerola pulp compared to the other preservation technologies employed. This is due to the greater BC concentration in the microencapsulated, as well as the pH reduction. Furthermore, over 180 days, microencapsulation better preserved the target compounds in acerola pulp compared to lyophilization, as evidenced by the superior content of BC in the former treatment, making it an appealing option for the food sector.

Considering the increasing number of low cost vegetable oil product adulterations, it is necessary to assess the authenticity of the lipid sources used in the dog food manufacture, consequently different brands and classifications of feed were analyzed to verify the product authenticity by gas chromatography (GC) with flame ionization detector (FID) and by electrospray ionization mass spectrometry (ESI-MS). Fatty acid (FA) composition analysis was performed to compare the FAs amount in samples with the respective guarantee levels stated by the manufacturers on its product label. Gas chromatography with flame ionization detector (GC-FID) results for omega-3 and 6 percentages are within the limits presented by each manufacturer, while the timnodonic + cervonic acids amount information presented on feed sample labels is not in accordance with GC-FID results. Consequently, the samples were analyzed by ESI-MS, the results exposed the chicken oil presence in the feed and eicosapentaenoic (EPA) + docosahexaenoic (DHA) acids absence, since no lipid profiles similar to fish oils or triacylglycerols (TAGs) containing these two FAs were found. Thus, the information presented on labels are in disagreement with the results obtained both by GC-FID FA composition analysis and by ESI-MS lipid profile analysis. Principal component analysis (PCA) confirmed that the main contribution was from FAs found by GC-FID.

Rosemary (Rosmarinus officinalis L.) is known for its bioactive compounds with high antioxidant potential and pharmacological properties, such as antibacterial, antidepressant and anti-inflammatory. These properties are attributed to the presence of (poly)phenolic compounds. In the literature there is no extraction of these compounds with a totally non-toxic solvent, capable of applying the extract directly to the food. This work aimed to optimize the extraction conditions of bioactive compounds from the rosemary leaves using water as solvent. According to the analysis of variance parameters, a cubic model of high order of significance was obtained with adjusted R2 (R squared) > 0.947. The optimal conditions of the antioxidant potential for conventional and ultrasonic agitation were: temperature 70 °C, 30 min of extraction and the solvent/solute ratio of 25, resulting in an antioxidant potential of 6861 and 7126 µmol L−1 Trolox, respectively. The electrospray ionization mass spectrometry (ESI(−)-MS/MS) analysis showed the presence of antioxidant compounds such as: carnosol (m/z 329.20), rosmanol (m/z 345.03) and rosmarinic (m/z359.14) acids. The response surface methodology evaluated the influence of the main parameters of the bioactive compounds extraction from rosemary using only water as solvent, in addition to the use of less time and sample mass, resulting in lower cost.

Coconut oil has several domestic uses and health benefits, which can be used in food, pharmaceuticals and cosmetics products. However, it has been the target of adulteration with lower price oils and fats, such as soybean oil. In this study, a fast, easy and simple methodology was used to detect low quantities of intentionally adulterated coconut oil with soybean oil by direct infusion electrospray ionization mass spectrometry (ESI-MS) at different levels (0, 2, 5, 10, 15, 20, 30, 50, 70 and 100%). In the oil industry, intentional adulterations usually occur with the addition of low quantities of soybean oil to coconut oil. Therefore, the suggested ESI-MS method is promising for routine analysis to guarantee the quality control of coconut oil since it is possible to detect adulteration with a minimal of 2% soybean oil addition.

The developed method (DM) allows to perform experiments in shorter time with reduced amount of sample and reagent for fatty acids (FA) determination in fermented milk samples. Design Expert software was employed to discover the greatest sonication time (7 and 20 min) and concentration for alkaline and acidic reactions (0.70 and 1.5 mol L-1). Validation procedures were applied in yogurt samples with diverse fat content, ranging from 1.22 to 2.83%, being in agreement with acceptable values. Besides, the intraday relative standard deviation (RSD) (1.86%) and interday RSD (4.23%) values confirmed the good accuracy of the proposed method for FA derivatization.

Vegetable oils have properties that are beneficial to the human skin, and so, they are being used increasingly as ingredients of many cosmetic preparations; however, they are targets of adulteration. This study will evaluate the authenticity of Brazilian cosmetics based on vegetable oils (sesame, peanut, sunflower, and almonds) to determine the composition of fatty acids by gas chromatography with flame ionization detection (GC-FID) and the percentage of fatty acids in conjunction with chemometric treatments (principal component analysis), and lipid profiles using direct infusion electrospray ionization mass spectrometry (ESI-MS). The results obtained were compared with the respective pure vegetable oils. Of the seven brands analyzed, three were revealed as authentic, three were found to be adulterated with the addition of large amounts of soybean oil, and one showed no vegetable oils. These results demonstrate the relevance of quality control for cosmetics based on vegetable oils, which are more susceptible to adulteration owing to their higher cost when compared with vegetable oils such as soybean.

Due to the amount of pigments, sugars and fibers found in fruits, the fatty acid quantification process leads to errors, such as its amount underestimation in the matrix. Therefore, the proposed method allows performing experiments in shorter time with reduced amount of sample and reagent. Design Expert software was used to find the validated time for alkaline and acidic reactions, which were six and eight minutes, respectively, and both concentration was 0.5 mol L-1. The validation was made for avocado pulp and different fruits were used for application of the method, such as: apple, mango, coconut and another avocado variety. Accuracy values ranged from 89.05 to 100.21%, being in accordance with acceptable values. Also the relative standard deviation (RSD)intra-day (0.30 to 1.30%) and the RSDinter-day values (0.32 to 1.44%) confirmed that the proposed method for fatty acid derivatization has good precision.

Omega-3 fish oil supplements are widely consumed as source of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, presenting beneficial effects on human health. This study aimed to evaluate fifteen brands of omega-3 fish oil supplements available in Brazilian market in order to estimate the Brazilian reality regarding those supplements. Twelve fatty acids were quantified by gas chromatography with a flame ionization detector (GC-FID), and lipid profile were obtained via mass spectrometry fingerprinting using direct electrospray ionization mass spectrometry (ESI-MS) to assess the form in which fatty acids are present as well as the possible fraud existence. Among all analyzed samples, thirteen brands were revealed as EPA and DHA sources (90.2-440.3 and 77.8-302.3 mg g-1lipid, respectively) in triacylglycerols (TAG) or ethyl esters (EE) form. However, two brands were discovered with addition of large amounts of soybean oil, leading the final consumer to ingest this low-cost oil believing that they are consuming adequate doses of EPA and DHA.