Application of lime peel oil composite nanoemulsion to prevent toxigenic fungi in nuts

Food byproduct oils may have antimicrobial impacts when used in coating and preservation. Nuts are known to suffer from toxigenic fungi and their related mycotoxins. The present study utilized lime oil emulsion to minimize fungal infection and reduce aflatoxin B1 (AFB1). Besides, it evaluated lime oil's impact on nuts' protection against oxidation and deterioration during storage. Lime oil was extracted using hydrodistillation, and gas chromatography (GC-MS) evaluated volatile constituents. Oil was loaded into a composite emulsion of whey protein, Arabic gum, gelatin, and carboxymethyl cellulose. The antimicrobial and antifungal properties of the nut-coating emulsion were evaluated. A simulated Aspergillus flavus infection experiment evaluated composite resistance for fungal infection and AFB1 production. Oxidation and acidity changes in nuts oil composition were evaluated by proximate analysis, fatty acid composition, and induction period. The oil majority was recorded for terpenes and monoterpenes, including limonene (44.69 ± 2.11%). The emulsion was characterized by zeta potential (-21.16 ± 1.28 mV), stability (99.61 ± 0.02%), and polydispersity index (0.41 ± 0.05). Antimicrobial properties recorded a high antibacterial inhibition zone (up to 28.37 ± 0.11 mm) and anti-mycotoxigenic fungi (up to 37.61 ± 0.24 mm). For the simulated experiment, fungal growth reduction ranged between 78.02% for filmed-peanut and 84.5% for filmed-almond, while AFB1 was not detected in filmed hazelnut and almond. During the one-year storage of samples, there was a slight change in nut oil composition and oxidation progress in filmed nuts, while there was a significant change in non-filmed nuts. The result recommended lime-composite as an edible nut coating that prevents aflatoxigenic contamination, oxidation changes, and improved shelf life.

Effect of Refining and Fractionation Processes on Minor Components, Fatty Acids, Antioxidant and Antimicrobial Activities of Shea Butter

Shea butter is becoming increasingly popular in foods, cosmetics and pharmaceutical products. This work aims to study the effect of the refining process on the quality and stability of fractionated and mixed shea butters. Crude shea butter, refined shea stearin, olein and their mixture (1:1 w/w) were analyzed for fatty acids, triacylglycerol composition, peroxide value (PV), free fatty acids (FFA), phenolic (TPC), flavonoid (TFC), unsaponifiable matter (USM), tocopherol and phytosterol content. Additionally, the oxidative stability, radical scavenging activity (RSA), antibacterial and antifungal activities were evaluated. The two main fatty acids in the shea butter samples were stearic and oleic. The refined shea stearin showed lower PV, FFA, USM, TPC, TFC, RSA, tocopherol and sterol content than crude shea butter. A higher EC50 was observed, but antibacterial activity was much lower. The refined olein fraction was characterized by lower PV, FFA and TFC in comparison with crude shea butter, but USM, TPC, RSA, EC50, tocopherol and sterol content was unchanged. The antibacterial activity was higher, but the antifungal activity was lower than those of crude shea butter. When both fractions were mixed, their fatty acid and triacylglycerol composition were similar to those of crude shea butter, but other parameters were different.

A Comprehensive Study of Lupin Seed Oils and the Roasting Effect on Their Chemical and Biological Activity

The present investigation aimed to study the impact of roasting on the chemical composition and biological activities of sweet and bitter lupin seed oils. Lupin oils were extracted using petroleum ether (40–60) with ultrasonic assisted method. Lupin Fatty acids, phytosterols, carotenoids, and total phenolic contents were determined. In addition, antioxidant, antimicrobial, and antifungal activities were evaluated. The results showed a ratio between 7.50% to 9.28% of oil content in lupin seed. Unroasted (bitter and sweet) lupin oil contained a high level of oleic acid ω9 (42.65 and 50.87%), followed by linoleic acid ω6 (37.3 and 34.48%) and linolenic acid ω3 (3.35 and 6.58%), respectively. Concerning phytosterols, unroasted (bitter and sweet lupin) seed oil reflected high values (442.59 and 406.18 mg/100 g oil, respectively). Bitter lupin oil contains a high amount of phenolics, although a lower antioxidant potency compared to sweet lupin oil. This phenomenon could be connected with the synergistic effect between phenolics and carotenoids higher in sweet lupin oil. The results reflected a more efficiently bitter lupin oil against anti-toxigenic fungi than sweet lupin oil. The roasting process recorded enhances the antimicrobial activity of bitter and sweet lupin seed oil, which is linked to the increment in bioactive components during the roasting process. These results concluded that lupin oil deems a novel functional ingredient and a valuable dietary fat source. Moreover, lupin oil seemed to have antifungal properties, which recommended its utilization as a carrier for active-antifungal compounds in food products.

The Effect of Wall Material Type on the Encapsulation Efficiency and Oxidative Stability of Fish Oils

Fish oil is the primary source of long-chain omega-3 fatty acids, which are important nutrients that assist in the prevention and treatment of heart disease and have many health benefits. It also contains vitamins that are lipid-soluble, such as vitamins A and D. This work aimed to determine how the wall material composition influenced the encapsulation efficiency and oxidative stability of omega fish oils in spray-dried microcapsules. In this study, mackerel, sardine waste oil, and sand smelt fish oil were encapsulated in three different wall materials (whey protein, gum Arabic (AG), and maltodextrin) by conventional spray-drying. The effect of the different wall materials on the encapsulation efficiency (EE), flowability, and oxidative stability of encapsulated oils during storage at 4 °C was investigated. All three encapsulating agents provided a highly protective effect against the oxidative deterioration of the encapsulated oils. Whey protein was found to be the most effective encapsulated agent comparing to gum Arabic and maltodextrin. The results indicated that whey protein recorded the highest encapsulation efficiency compared to the gum Arabic and maltodextrin in all encapsulated samples with EE of 71.71%, 68.61%, and 64.71% for sand smelt, mackerel, and sardine oil, respectively. Unencapsulated fish oil samples (control) recorded peroxide values (PV) of 33.19, 40.64, and 47.76 meq/kg oil for sand smelt, mackerel, and sardine oils after 35 days of storage, while all the encapsulated samples showed PV less than 10 in the same storage period. It could be concluded that all the encapsulating agents provided a protective effect to the encapsulated fish oil and elongated the shelf life of it comparing to the untreated oil sample (control). The results suggest that encapsulation of fish oil is beneficial for its oxidative stability and its uses in the production of functional foods.

Non-traditional Oils Encapsulation as Novel Food Additive Enhanced Yogurt Safety Against Aflatoxins

BACKGROUND AND OBJECTIVE

Hibiscus oil (HO) and black cumin oil (BCO) are interesting oils which give a source for photochemical. Yoghurt recognized for health benefits, but mycotoxin is a food problem. The aim was adjusting non-traditional capsulated oils for minimizing mycotoxins in dairy products (yoghurt) and biological systems.

MATERIAL AND METHODS

Oils fatty acid composition were evaluated. Micro and nano-emulsion designed to achieve food safety and shelf-life extension. Encapsulated emulsions evaluated by in vitro and in vivo models for several aflatoxins reduction through yogurt fortification model, for in vivo model reduction estimated as enhancement of rat's blood biochemical parameters. Concerning the in vitro model, changes of supplemented yoghurt properties were estimated.

RESULTS

Linoleic followed by oleic acid showed a high content in these oils representing omega fatty acids. Gamma fractions presented in considerable values (>50% of vitamin E). To evaluate encapsulated oils reduction on aflatoxins (AFs), it was estimated for in vitro and in vivo models. The in vitro reduction of aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) recorded 31.6 and 34.9%, respectively in plain yogurt. However, yogurt fortification by oil-capsules upgraded the ratio for AFB1 (63.9%) and AFM1 (66.4%). The best reduction recorded using BCO fortification. For in vivo study, supplementation of rat's diet by BCO micro-capsule declared an enhancement of biochemical parameters against aflatoxin G1 (AFG1) effects. Fortified yogurt offered enhancement of viscosity and water holding capacity properties.

CONCLUSION

Encapsulated emulsions recorded high AFs reduction in fortified yogurt and experimental rat's model. Yogurt fortification enhanced its quality characteristics and shelf-life that give a recommendation for the application.

Blends of rapeseed oil with black cumin and rice bran oils for increasing the oxidative stability

For the increase of oxidative stability and phytonutrient contents of rapeseed oil 5, 10 and 20 % blends with rice bran oil and black cumin oil were prepared. Profiles of different bioactive lipid components of blends including tocopherols, tocotrienols, phytosterols and phytostanols as well as fatty acid composition were carried out using HPLC and GLC. Rancimat was used for detecting oxidative stability of the fatty material. The blends with black cumin seed oil characterized higher level of α- and γ-tocopherols as well as all isomers of tocotrienols. Presence of rice bran oil in blends leads to increased tocotrienols amounts, β-sitosterol and squalene. Blending resulted in lowering ratio of PUFA/SFA and improves stability of these oils. The ratio of omega-6/omega-3 raises from 2.1 in rapeseed oil to 3.7 and 3.0 in blends with black cumin and rice bran oils, respectively. Addition of 10 and 20 % of black cumin and rice bran oils to rapeseed oil were influenced on the oxidative stability of prepared blends. The results appear that blending of rapeseed oil with black cumin seed oil or rice bran oil enhanced nutritional and functional properties via higher oxidative stability as well as improved phytonutrient contents.