A novel bleaching approach: Microwave assisted sunflower oil bleaching and optimization

The factors affecting the microwave bleaching of sunflower oil and the interaction between them were investigated and optimized by response surface methodology using a three-factor five-level central composite rotatable design. Microwave power, time and the amount of bleaching clay were selected as independent variables studied in the range of 70-120 W, 2-15 min, and 0.01-0.5%. The dependent variables that measure the bleaching efficiency and oil quality were evaluated as hue angle, chroma and totox value. Optimization was carried out by minimizing totox and chroma and maximizing hue angle. Hue angle, chroma and totox were found as 96.91, 37.66 and 23.31 under optimal conditions. Optimal microwave bleaching was successfully performed by using less bleaching clay (0.4%) and a shorter time (8 min) compared to the current industrial application without any adverse effect on oil quality. Hence, microwave bleaching is thought to be an alternative method for the bleaching of edible oils.

Total gossypol and oxidation levels of refined cottonseeds oils and crude peanut oils produced in Burkina Faso

Edible oils produced and consumed in Burkina Faso often do not meet established standards. The objective of this study was to evaluate the total gossypol level of refined cottonseeds oils and the oxidation state of crude peanut oils and refined cottonseeds oils in Burkina Faso to determine the impact on consumer health. A total of 61 samples including crude peanut oils and refined cottonseeds oils were collected in Ouagadougou, Bobo Dioulasso and surrounding areas. Total Gossypol and p-Anisidine value were determined by spectrophotometry. Peroxide value, acid value, soap residual value and mineral oils were determined by chemical methods. Total oxidation (Totox) value was determined by mathematical prediction. Overall, Gossypol total average of cottonseeds oils analyzed in this study was 0.032%. The p-Anisidine value average was 1.80 for refined cottonseeds oils and 11.65 for crude peanut oils. The Totox averages were respectively 19.37 and 28.36 for refined cottonseeds and crude peanut oils. The average peroxide values for refined cottonseeds oils and peanut crude oils were 8.52 and 8.33 mEq O2/Kg, respectively (p<0.05). The average acid values were 0.27 and 1.95 mg KOH/g for refined cottonseeds oils and crude peanut oils, respectively (p<0.05). None of the oils showed any mineral oil trace. The average residual soap values were respectively 1.47 and 8.32 ppm for peanut oils and cottonseeds oils (p<0.05). The majority values determined conformed to the Codex Alimentarius standard despite some cases of non-compliance. It is essential to improve the processes of oils production and conservation in order to have quality oils to guarantee the health of the consumer.

Bleaching optimization of tuna (Thunnus sp.) oil using response surface methodology

The quality of crude tuna (Thunnus sp.) oil aimed for food-sector-purpose can be improved by performing purification. The present study was aimed to optimize the bleaching step during the purification process and determine the optimum variable conditions using response surface methodology (RSM) in obtaining the lowest oxidation parameters value to meet the International Fish Oil Standard (IFOS) standard. A total of five responses including free fatty acids (FFA) value, acid value (AV), peroxide value (PV), anisidine value (AnV) and total oxidation (Totox) value were studied using central composite design (CCD), a full factorial design with all combinations of the factors at two levels (high, +1, and low, −1 level), repeated thrice; applied for two variable factors (adsorbent concentration [A];% and adsorption time [B]; mins). The optimum model suggested by the program was a quadratic model for FFA and AnV, and a linear model for AV, PV and Totox value. The optimum response was reached by the combination of 5% adsorbent concentration [A] with adsorption time [B] of 20 mins. This formula reduced the FFA value, AV, PV, AnV, and Totox Value up to 56.57%, 55.36%, 88.86%, 69.69% and 77.03%, respectively. The purified tuna oil has a clear yellow colour appearance with a rising percentage of pure fish oil for EPA and DHA of 10.71% and 11.50% from crude tuna fish oil.

Caracterização físico-química de manteigas de frutos amazônicos

Este trabalho teve como objetivo caracterizar manteigas comerciais obtidas a partir dos frutos amazônicos bacuri (Platonia insignis), cacau (Theobroma cacao), cupuaçu (Theobroma grandiflorum), murumuru (Astrocaryum murumuru), tucumã (Astrocaryum aculeatum) e ucuuba (Virola surinamensis) quanto às propriedades físico-químicas e ao perfil de ácidos graxos. Para tanto, as manteigas foram analisadas de acordo com os métodos oficiais descritos pela American Oil Chemists' Society (AOCS) quanto aos teores de ácidos graxos livres, índice de acidez, dienos conjugados, índice de peróxidos, p-anisidina, valor totox, índices de saponificação, iodo e refração, ponto de fusão e matéria insaponificável. As manteigas apresentaram acidez acima do limite estabelecido pela regulamentação, evidenciando degradação hidrolítica, sobretudo nas de cupuaçu e ucuuba. Ao contrário para os índices de peróxidos, a formação de compostos primários foi abaixo do limite máximo permitido pela regulamentação. A manteiga de bacuri apresentou o maior valor totox, pelos mais altos índices de peróxidos e p-anisidina. Em geral, as manteigas apresentaram elevadas quantidades de ácidos graxos saturados. Maiores quantidades de ácido graxo monoinsaturado (oleico) foram encontradas nas manteigas de cupuaçu, bacuri e cacau. Palavras-chave: Ácidos graxos. Propriedades físico-químicas. Manteigas vegetais. Physicochemical characterization of amazonian fruit butters Abstract This study aimed to characterize commercial butters obtained from Amazonian fruits bacuri (Platonia insignis), cocoa (Theobroma cacao), cupuaçu (Theobroma grandiflorum), murumuru (Astrocaryum murumuru), tucumã (Astrocaryum aculeatum) and ucuuba (Virola surinamensis) regarding the physicochemical properties and the fatty acid profile. For this purpose, the butters were analyzed according to the official methods described by the American Oil Chemists' Society (AOCS) regarding the levels of free fatty acids, acidity index, conjugated dienes, peroxide index, p-anisidine, totox value, saponification, iodine and refraction, melting point and unsaponifiable matter. The butters showed acidity above the limit established by regulation, showing hydrolytic degradation, especially in cupuaçu and ucuuba. In contrast to the peroxide values, the formation of primary compounds was below the maximum limit allowed by regulation. Bacuri butter had the highest totox value, due to the higher levels of peroxides and p-anisidine. In general, the butters showed high amounts of saturated fatty acids. Higher amounts of monounsaturated fatty acid (oleic) were found in cupuaçu, bacuri and cocoa butters. Keywords: Fatty acids. Physicochemical properties. Vegetable butters.

Fish oil supplements, oxidative status, and compliance behaviour: Regulatory challenges and opportunities

Background Fish oil supplements that are rich in omega-3 long-chain polyunsaturated fatty acids (n-3 PUFAs). PUFAs are among the most widely-used dietary supplements globally, and millions of people consume them regularly. There have always been public concerns that these products should be guaranteed to be safe and of good quality, especially as these types of fish oil supplements are extremely susceptible to oxidative degradation. Objectives The aim of the current study is to investigate and examine the oxidation status of dietary supplements containing fish oils and to identify important factors related to the oxidation status of such supplements available in the United Arab Emirates (UAE). Methods A total of 44 fish oil supplements were analysed in this study. For each product, the oxidative parameters peroxide value (PV), anisidine value (AV), and total oxidation (TOTOX) were calculated, and comparisons were made with the guidelines supplied by the Global Organization for EPA and DHA Omega-3s (GOED). Median values for each of the above oxidative parameters were tested using the Kruskal-Wallis and Mann-Whitney U tests. P values < 0.05 were chosen as the statistically significant boundary. Results The estimate for the average PV value was 6.4 with a 95% confidence interval (CI) [4.2–8.7] compared to the maximum allowable limit of 5 meq/kg. The estimate for the average P-AV was 11 with a 95% CI [7.8–14.2] compared to the maximum allowable limit of 20. The estimate for the average TOTOX value was 23.8 meq/kg with a 95% CI [17.4–30.3] compared to the maximum allowable limit of 26 according to the GOED standards. Conclusion This research shows that most, although not all, of the fish oil supplements tested are compliant with the GOED oxidative quality standards. Nevertheless, it is clear that there should be a high level of inspection and control regarding authenticity, purity, quality, and safety in the processes of production and supply of dietary supplements containing fish oils.

Application of Astaxanthin and its Lipid Stability in Bakery Product

The application of astaxanthin is not widely studied especially on its uses and relationship toward lipid stability in food products. Therefore, this study was aimed to determine the antioxidant activity of astaxanthin and evaluate its lipid stability, physicochemical and sensory properties of astaxanthin formulated cookies. The antioxidant activity of astaxanthin was analyzed using DPPH, HRSA and FRAP assays. Meanwhile, lipid stability including peroxide value (PV), p-anisidine value (P-aV) and TOTOX value was evaluated periodically on the formulated cookies (10%, 15% and 20% of astaxanthin). Astaxanthin recorded inhibition percent (I%) value of DPPH 97%. The hardness of the cookies significantly decreased (P<0.05) as the astaxanthin were increased. The amount of astaxanthin added did not affect the taste acceptability of all formulated cookies. Storage time has affected on PV and P-aV value, but not affected on the TOTOX value. The significance of this study will lead to the potential application of astaxanthin as functional foods, thus provide health benefits.

Quality Parameters of Palm Olein, Palm Kernel Oil and its Blends Subjected to Thermal Stress using Photometric Technology

There is no much information regarding the partial replacement of palm olein with palm kernel oil. Palm olein mixed with palm kernel oil is commonly sold in Nigeria market today without proper blending and without determination of their suitability to consumer also ignorant of what ratio to be blended. Therefore, blends of palm olein (POL) and palm kernel oil (PKO) were formulated to assess their stability under elevated temperature using a fast, simple and reliable CDR palm oil tester photometric technology. The results were then compared with those obtained in POL. The blends studied were to investigate the effects of palm kernel oil partial replacement on the chemical stability of palm olein. the blends as partial replacement were missed in the ratio of PKO:POL(100:0), PKO:POL(80:20), PKO:POL(60:40) and POL:PKO(100:0), POL:PKO(80:20), POL:PKO(60:40). The POL, PKO and its blends were heated at 100, 150 and 200ᵒC. The time of heating were 20, 40 and 60mins respectively, making a total of 1 hour for heating without any frying operations. The physicochemical properties of the oil samples were fatty acid composition, free fatty acid, peroxide value, iodine value, anisidine value, cloud point, colour, melting point, viscosity and totox value were evaluated over heating time. Blending palm olein (POL) unsaturated oils with saturated (PKO) generally improved the parameters comparable to those demonstrated in palm olein (POL) and palm kernel oil alone. The result showed that as PKO was increased the concentration of saturated fatty acid also increased while unsaturated fatty acid decreased. Saturated oils were generally more stable to oxidation and less sensitive to thermal stress. Increase in the amount of PKO lead to reduction in FFA.

Investigation of lamb fat quality attributes during deodorization

Edible lamb fat is an illustrious frying fat due to its good flavor and stability to oxidation. Fat deodorization is a vacuum–steam distillation process that is accomplished for removing the unwanted components such as free fatty acids and volatile compounds. The present work has studied the kinetics of lamb fat deodorization under different temperatures in a batch deodorization system. Variations of acid value (AV), peroxide value, p-Anisidine value, TOTOX value and total color difference were measured during the deodorization process. The Logarithmic, Wang and Singh, Hénon et al., and linear models were fitted with obtained data using nonlinear regression method. Results indicated that the Logarithmic and Henon et al. models gave the best fitness respectively with AV and p-Anisidine value, based on the statistical criteria of correlation coefficient (R2), reduced chi-square (χ2) and root mean square error (RMSE). Furthermore, the linear model was selected as the best model to describe the variations of TOTOX value and peroxide value during the deodorization process.

Oxidative Stability of Soybean Oil Supplemented with Pod Coat Extracts of Cluster Bean

The aim of present work was to determine the potency of phenolic extracts from cluster bean pod coats in improving shelf life of soybean oil. Pod coats of cluster bean were extracted with three solvents (acetone, ethylacetate and chloroform). Crude soybean oil samples were stabilised by adding different extracts at 1000 and 2000 ppm concentration and effect of addition of these extracts on oxidative stability of crude soybean oil at 50°C was observed. Rate of oxidative degradation of crude soybean oil was lowest in the sample treated with acetone extract (2000 ppm). The value of various oxidative quality parameters of crude soybean oil supplemented with acetone extract (2000 ppm) after 28 days of incubation are peroxide value (26.77 meq/kg oil), free fatty acids content (2.637%), p-anisidine value (25.18), TOTOX value (78.72), conjugated dienes (28.47%), conjugated trienes (13.97%) and TBA value (31.59 meq malonaldehyde/g). Results of present study indicate that pod coat extracts of cluster bean possess remarkable antioxidant potential and considerably lowered the rate of oxidative deterioration of crude soybean oil.

Effect of Intrinsic and Extrinsic Factors on the Storage Stability of Sardine Oil

Oil extracted from pelagic fishes, rich in n-3 polyunsaturated fatty acids (PUFA) like Eicosapentaenoic acid and Docosahexaenoic acid, have numerous health benefits. The oil also contains impurities like di- and mono glycerides, free fatty acids, phospholipids, unsaponifiable matter, metal ions and volatile compounds. Most of these impurities are removed by refining process without affecting valuable n-3 PUFA. However, due to the presence of residual impurities, environmental factors and higher degree of unsaturation, the oil exhibit hydrolytic and oxidative instability during storage. This study was aimed to identify the most detrimental factors causing hydrolytic and oxidative instability and deterioration of n-3 PUFA content in sardine oil during five-week storage. The effect of various extrinsic and intrinsic factors on the storage stability was investigated. The hydrolytic and oxidative instability was estimated by free fatty acid (FFA) content and totox value (TV) respectively. Moisture, sunlight, ferric ions and FFA were found to be most detrimental to oil quality and n-3 PUFA content. Although, addition of phosphotidylcholine and phospholipase-A showed high degree of hydrolytic and oxidative instability, n-3 PUFA destruction was minimal. Interestingly, even in the presence of ferric ions and FFA, phosphotidylcholine and phospholipase-A exhibited n-3 PUFA protection. The exact mechanism by which phosphotidylcholine and phospholipase-A offered protection to n-3 PUFA needs further investigation. From this study, it can be concluded that removing ferric ions, moisture and FFA from crude oil during refining is essential. Further, the refined oil must be stored under dark conditions in airtight containers to retard deterioration of oil quality.