Characterization, Sensory and Oxidative Stability Analysis of Vegetable Mayonnaise Formulated with Olive Leaf Vinegar as an Active Ingredient

A novel Pickering emulsion stabilized solely by agar-glycine Maillard conjugates

A novel Pickering emulsifier was developed through the Maillard reaction between acidolyzed agar and glycine. The resulting agar-glycine (Agar-Gly) Maillard product particles effectively stabilized a long-term Pickering emulsion at low pH (as low as 3) and medium oil content (40 %-50 %) with a particle concentration of 1 %. Microstructural analysis revealed that Agar-Gly particles adsorbed around the droplets, forming a typical O/W Pickering emulsion. The formation of a dense and regular three-dimensional gel network around the droplets was crucial in restricting droplet movement and ensuring emulsion stability. This stability was significantly superior to emulsions stabilized solely with agar or a mixture of agar and glycine (Agar+Gly), owing to synergistic effects between particle interfacial layers and spatial site resistance. Incorporating the Agar-Gly Maillard product into low-fat mayonnaise not only markedly reduces its greasiness but also provides consumers with a low-fat, healthy alternative. Furthermore, Agar-Gly used as a Pickering stabilizer, it offers an easy mode of application for agar that does not require dissolution at elevated temperatures. This provides a straightforward and promising avenue for the use of agar in the high-value food industry.

Current Trends in Food Processing By-Products as Sources of High Value-Added Compounds in Food Fortification

Along the food production chain of animal, fish, and vegetable products, a huge amount of by-products are generated every year. Major nutritional, financial, and environmental advantages can be achieved by transforming them into functional ingredients for food formulation and fortification. In this review, we investigated various conventional and emerging treatments recently employed to obtain functional ingredients rich in proteins, fibers, and bioactive compounds from vegetables, fish, meat, and dairy by-products. The optimal enrichment level in food as well as the nutritional, techno-functional, and sensory properties of the final food were also discussed. Novel technologies such as ultrasounds, microwaves, and high pressure have been successfully adopted to enhance the extraction of target compounds. The functional ingredients, added both in liquid or powder form, were able to improve the nutritional quality and antioxidant potential of food, although high levels of fortification may cause undesired changes in texture and flavor. This review provides important considerations for further industrial scale-up.

Lipid oxidation in emulsions: New insights from the past two decades

Lipid oxidation constitutes the main source of degradation of lipid-rich foods, including food emulsions. The complexity of the reactions at play combined with the increased demand from consumers for less processed and more natural foods result in additional challenges in controlling this phenomenon. This review provides an overview of the insights acquired over the past two decades on the understanding of lipid oxidation in oil-in-water (O/W) emulsions. After introducing the general structure of O/W emulsions and the classical mechanisms of lipid oxidation, the contribution of less studied oxidation products and the spatiotemporal resolution of these reactions will be discussed. We then highlight the impact of emulsion formulation on the mechanisms, taking into consideration the new trends in terms of emulsifiers as well as their own sensitivity to oxidation. Finally, novel antioxidant strategies that have emerged to meet the recent consumer's demand will be detailed. In an era defined by the pursuit of healthier, more natural, and sustainable food choices, a comprehensive understanding of lipid oxidation in emulsions is not only an academic quest, but also a crucial step towards meeting the evolving expectations of consumers and ensuring the quality and stability of lipid-rich food products.

A Validated HPLC-RID Method for Quantification and Optimization of Total Sugars: Fructose, Glucose, Sucrose, and Lactose in Eggless Mayonnaise

Mayonnaise is an oil-in-water emulsion containing 70–80% finely dispersed droplets of oil in a continuous phase of water. Since mayonnaise has a sour and acidic taste, its sugar profile is barely noticed and thus often disregarded. However, today, there are various variants of mayonnaise available on the market; hence, it is crucial to understand their mono- and disaccharide profile, in order to determine the precise total sugar composition. The traditional methods of sugar analysis available, such as titration, can only quantify sucrose and are unable to differentiate between mono- and disaccharides. The aim of this study was to develop and validate a method for the quantification of total sugars, including fructose, glucose, sucrose, and lactose, in eggless mayonnaise, using a high performance liquid chromatography refractive index detector (HPLC-RID). Sugars were separated on an amino column with an oven temperature of 35 °C, using an isocratic solvent system consisting of a 75:25 v/v mixture of acetonitrile and HPLC water, at a 0.9 mL/min flow rate with RID. Method validation was performed for the linearity, specificity, precision, accuracy, LOD, LOQ, and robustness. A linearity for total sugars, with a regression coefficient of 0.9998, was obtained within the range of 0.05024 to 10.048 mg/mL. The relative standard deviation was less than 2.0% for the intra-day and inter-day precision. The accuracy was found to be 96.78–108.88% using a three-level recovery method. The LOD and LOQ were also found to be suitable. The samples used in this study contained 0.24–10.32% total sugars. The sucrose value obtained matched the label claim of the products and no significant differences were observed between results in a paired sample t-test. This showed the applicability of the proposed method for analyzing the sugar profile in a finished product. Routine analysis of total sugars in eggless mayonnaise and similar finished products can thus be performed using this technique, which was found to be simple, rapid, and reproducible.

Simultaneous Extraction of Bioactive Compounds from Olea europaea L. Leaves and Healthy Seed Oils Using Pressurized Propane

Olive leaves (OL) are products of olive cultivation with a high commercial value because they contain valuable bioactive compounds. Chia and sesame seeds have a high functional value because of their attractive nutritional properties. When combined in the extraction process, the two products constitute a product of high quality. The use of pressurized propane in vegetable oil extraction is advantageous because it provides solvent-free oil. This study aimed to combine two high-quality products to obtain oils with a unique combination of attractive nutritional properties and high levels of bioactive compounds. The mass percentage yields of the OL extracts with chia and sesame oils were 23.4% and 24.8%, respectively. The fatty acid profiles of the pure oils and their respective OL-enriched oils were similar. There was an aggregation of the 35% and 32% (v/v) bioactive OL compounds in chia and sesame oils, respectively. OL oils exhibited superior antioxidant capacities. The induction times of the OL extracts with the sesame and chia oils increased by 73% and 4.4%, respectively. Incorporating OL active compounds in healthy edible vegetable oils using propane as a solvent promotes the reduction of lipid oxidation, improves the lipid profiles and health indices of the oils, and forms a product with attractive nutritional characteristics.