Stability of Bioactive Compounds in Olive-Pomace Oil at Frying Temperature and Incorporation into Fried Foods

Recent advances in spectroscopic approaches for assessing the stability of bioactive compounds and quality indices of olive oil during deep-frying: Current knowledge, challenges, and implications

Foods fried in olive oil received great attention due to its bioactive profile, antioxidants, high stability, and health benefits. However, several chemical alterations contribute to olive oil degradation during deep-frying (DF), and negatively modify its safety and quality. Therefore, measuring the quality indices of olive oil is a vital topic. The classical chemical approaches are destructive and use toxic chemicals, thus, a harmless and real-time analytical technique has become increasingly critical. This review highlights the recent advances of spectroscopic technologies (STs) stand-alone or integrated with chemometrics to provide reliable, rapid, low-cost, sustainable, multi-parametric, and eco-friendly method for monitoring the quality and safety of olive oil during thermal processing, moreover, the limitations of STs are included. The present review offers fundamental insights regarding the degradation of deep-fried olive oil and provides recent evidence in spectroscopy that can be used as consistent method, providing more benefits for the consumers and food industry.

Technological innovations in margarine production: Current trends and future perspectives on trans-fat removal and saturated fat replacement

The margarine market is growing globally due to its lower cost, ease of availability, large-scale commercialization, and expanding market in the bakery and confectionary industries. Butter contains greater amounts of saturated fat and has been associated with cardiovascular diseases. The trans fats generated through the hydrogenation process have several adverse impacts on human health, such as the risk of atherosclerosis, coronary heart disease, postmenopausal breast cancer, vision and neurological system impairment, type II diabetes, and obesity. Therefore, it is important to formulate margarine, low in saturated and trans fats using innovative technologies such as novel hydrogenation, interesterification techniques, and oleogel technology. By utilizing these technologies and oils with a healthy lipid profile, margarine manufacturers are able to produce healthier margarine. This review covers recent technological advancements in margarine, which include various hydrogenation techniques such as high-voltage atmospheric cold plasma hydrogenation, microwave plasma hydrogenation, dielectric-barrier discharge plasma hydrogenation, and interesterification based on supercritical CO2 systems. In addition, the application of interesterified oil and oleogel (structured vegetable oils) in the production of margarine low in saturated fat is comprehensively discussed, with emphasis on the utilization of unconventional sources of oils such as tiger nut oil, Moringa oleifera seed oil, Irvingia gabonensis seed fat, winged bean oil, and hemp seed oil. The novel hydrogenation techniques can hydrogenate oils without formation of trans fats, and such hydrogenated oils could be employed in the formulation of trans-fat-free margarine. Interesterified oil treated with supercritical CO2 was employed in healthy margarine development. Using the oleogel technique, various unconventional oil sources can be used in margarine formulations. The incorporation of oleogel in margarine makes it possible to improve the lipid profile of margarine due to a reduction in saturated fat content. All of these novel techniques have the potential to revolutionize the margarine industry by enabling the production of high-quality, healthy margarine.

Changes in stability, phytonutrients, 3-chloropropanol esters and glycidyl esters of peanut oil-based diacylglycerols during heat treatment

Diacylglycerol (DAG) is generally considered one of the precursors of 3-chloropropanol esters (3-MCPDE) and glycidyl esters (GEs). This study aimed to evaluate static heating and stir-frying properties of peanut oil (PO) and PO based 58% and 82% DAG oils (PDAG-58 and PDAG-82). Observations revealed that, phytonutrient levels notably diminished during static heating, with PDAG exhibiting reduced oxidative stability, but maintaining a stability profile similar to PO over a short period. During stir-frying, 3-MCPDE content initially increased and then decreased whereas the opposite was observed for GEs. Furthermore, as temperature, and NaCl concentration increased, there was a corresponding increase in the levels of 3-MCPDE and GEs, although remained within safe limits. When used in suitable concentrations, these findings underscore the potential of DAG, as a nutritionally rich and oxidatively stable alternative to conventional cooking oils, promoting the use of DAG edible oil in heat-cooked food systems.

Lipid Quality Changes in French Fries, Chicken Croquettes, and Chicken Nuggets Fried with High-Linoleic and High-Oleic Sunflower Oils in Domestic Deep Fryers

The quality of fried products greatly depends on the changes occurring during frying. The purpose of this work was to study the lipid quality changes taking place in selected frozen foods after domestic deep-frying. Conventional, high-linoleic sunflower oil (HLSO) and high-oleic sunflower oil (HOSO) were used, and the frozen foods selected were French fries, croquettes, and nuggets. The foods were fried in domestic fryers under discontinuous conditions. Analyses included fatty acid composition, sterols, tocopherols, squalene, and lipid alteration levels. In all fried foods, the content of lipids increased after frying, which is consistent with previous findings. However, the lipid exchange between the food and the oil greatly depended on the food characteristics. Specifically, the levels of frying oil in the food lipids were about 90, 40, and 58% for French fries, croquettes, and nuggets, respectively. The main results obtained showed that lipid alteration levels considerably decreased and amounts of sterols and tocopherols significantly increased in French fries' lipids after frying. In both chicken products, croquettes and nuggets, the best quality improvement observed was a significant decrease in cholesterol in food lipids due to the lipid exchange. Overall, frying with HLSO and HOSO improved the quality and nutritional properties of all products tested.

Looking into the lipid profile of avocado and byproducts: Using lipidomics to explore value-added compounds

Consumer priorities in healthy diets and lifestyle boosted the demand for nutritious and functional foods as well as plant-based ingredients. Avocado has become a food trend due to its nutritional and functional values, which in turn is increasing its consumption and production worldwide. Avocado edible portion has a high content of lipids, with the pulp and its oil being rich in monounsaturated fatty acids and essential omega - 3 and omega - 6 polyunsaturated fatty acids (PUFA). These fatty acids are mainly esterified in triacylglycerides, the major lipids in pulp, but also in minor components such as polar lipids (phospholipids and glycolipids). Polar lipids of avocado have been overlooked despite being recently highlighted with functional properties as well. The growth in the industry of avocado products is generating an increased amount of their byproducts, such as seed and peels (nonedible portions), still undervalued. The few studies on avocado byproducts pointed out that they also contain interesting lipids, with seeds particularly rich in polar lipids bearing PUFA, and thus can be reused as a source of add-value phytochemical. Mass spectrometry-based lipidomics approaches appear as an essential tool to unveil the complex lipid signature of avocado and its byproducts, contributing to the recognition of value-added lipids and opening new avenues for their use in novel biotechnological applications. The present review provides an up-to-date overview of the lipid signature from avocado pulp, peel, seed, and its oils.

Olive Pomace Oil Structuring for the Development of Healthy Puff Pastry Laminating Fats: The Effect of Chilling Storage on the Quality of Baked Products

Developing puff pastry (PP) laminating fats (LFs) with sustainable structured olive pomace oil (OPO) could contribute to its increased valorization. This study evaluated the physicochemical stability of four OPO-based LFs or margarines and the performance of their baked PP counterparts during two months of chilling storage at 4 °C. LF samples, developed at the laboratory scale, contained 41% (LF1 and LF2) OPO and 31% (LF3 and LF4) OPO together with 10% cocoa butter when using two static initial crystallization conditions (room temperature for LF1 and LF3, freezer for LF2 and LF4) before storage. During the storage period, the proximate composition, thermal and dynamic rheological properties, firmness and spreadability, oil-binding capacity, color, and lipid oxidation of the four LF samples were examined, along with the baking performance and textural properties of the PP counterparts. The initial cooling rate had minimal significance. Cocoa butter negatively influenced post-crystallization processes occurring in OPO-based LF3 and LF4, resulting in increased hardness and reduced performance after 18 days of storage, attributed, at least partially, to a high amount of 1,3-dipalmitoyl-2-oleoyl-glycerol (POP), mainly from cocoa butter. Conversely, OPO-based LF1 and LF2 maintained their quality and were stable for two months without apparent granular crystal formation.

Functionality of Puff Pastry Olive Pomace Oil-Based Margarines and Their Baking Performance

Designing healthier lipids is a current approach to developing potential functional foods. Olive pomace oil (OPO) has beneficial effects on human health, attributed to its high oleic acid content and unique bioactive compounds. Four puff pastry margarines (PP-M), based on OPO (M1, M2 at 40.8%, and M3, M4 at 30.8%, and cocoa butter at 10%) combined with low molecular weight organogelators, were prepared using two initial cooling rates (M1, M3 at 0.144 °C/min and M2, M4 at 0.380 °C/min) and compared to both commercial puff pastry (PP) butter (CB) and fatty preparation (CFP). Subsequently, six baked PP counterparts were elaborated. Physical-chemical, mechanical properties, and lipid profiles were analyzed in M1-M4 and PP, while thermal properties were determined in M1-M4. Sensory analysis was carried out in PP-M1 and PP-M3 counterparts. Elasticity (G') of M1-M4 samples was between that of controls CB and CFP, although a higher OPO content reduced viscous modulus (G″). The initial cooling rate did not affect the melting behavior of M1-M4. The firmness of PP-M1 was similar to that of PP-CB and PP-CFP, and the better spreadability and plasticity of M1 positively favored PP puffing. In addition, PP-M1 had 36.8% less SFA content than baked PP-CB, and its overall acceptability was similar. For the first time, a new margarine with high OPO content, showing adequate firmness, spreadability, and plasticity, was formulated, which gave rise to PP with appropriate performance and sensory quality and a healthy lipid profile.

Quality and Nutritional Changes of Traditional Cupcakes in the Processing and Storage as a Result of Sunflower Oil Replacements with Refined Olive Pomace Oil

Recent nutritional studies have shown that the regular consumption of olive pomace oil (OPO) contributes to cardiovascular and cardiometabolic disease prevention. OPO could be a healthier alternative to the polyunsaturated oils employed in a number of bakery foods. However, little is known about the quality and nutritional changes of OPO in these products, especially the amounts of its bioactive components that finally reach consumers. The aim of this research was to evaluate refined OPO as a substitute for sunflower oil (SO) in cupcakes specially manufactured with a 6-month shelf-life. The influence of processing and storage on lipid oxidative changes and the levels of OPO bioactive components was studied. OPO samples exhibited much higher resistance to oxidative degradation in the processing and especially after storage, which had a greater oxidative impact. OPO reduced considerably the levels of oxidised lipids. HPLC analysis showed hydroperoxide triglyceride concentrations of 0.25 (±0.03) mmol/kg fat against 10.90 (±0.7) mmol/kg in the control containing SO. Sterols, triterpenic alcohols and triterpenic acids remained unchanged, and only slight losses of squalene (8 wt%) and α-tocopherol (13 wt%) were observed in OPO after processing and storage, respectively. Therefore, OPO preserved its nutritional properties and improved the quality and nutritional value of the cupcakes.

Assessment of the Physicochemical Properties of Fragrant Rapeseed Blended Hotpot Oil by Principal Component Analysis

In this study, a nutritious, healthy Chongqing hotpot oil with excellent flavor was blended while considering nutrition, flavor, and health aspects. Four blended hotpot oils prepared from fragrant rapeseed, palm, sesame, and chicken oils were analyzed to determine their physicochemical properties, antioxidant capacities, levels of harmful substances, and nutritional compositions, and their sensory qualities were evaluated. Principal component analysis was performed to identify the best hotpot oil (10% chicken oil + 20% palm oil + 10% sesame oil + 60% fragrant rapeseed oil), which exhibited good antioxidant capacity (Oxidation Stability Index: 7.95 h; 2,2-diphenyl-1-picrylhydrazyl: 168.6 μmol/kg, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate): 116.7 μmol/kg, and ferric-reducing/antioxidant power: 63.9 μmol/kg), a high sensory score (7.7/10), stable physicochemical properties (acid value: 0.27 mg/g and peroxide value: 0.01 g/100 g), and high tocopherol (54.22%), and phytosterol retention (98.52%) after boiling for 8 h. Although the 3,4-benzopyrene content of this hotpot oil exceeded the EU standard after boiling for 7 h, the increase in the amount of harmful substances was the lowest.

Development and Physico-Chemical Characterization of Healthy Puff Pastry Margarines Made from Olive-Pomace Oil

Due to its characteristic aroma and flavor, puff pastry (PP) prepared with butter is more accepted than that made with margarine, yet a high saturated fat consumption is associated with cardiovascular disease. This work studies the potential of olive-pomace oil (OPO) as main ingredient of PP margarines together with different organogelator agents to imitate the technological properties of a commercial fatty preparation (CFP). Rheological and textural properties were measured in all formulated margarines (FM) and, additionally, thermal and microstructural properties, and fatty acid (FA) profiles were analyzed in some selected FM. The different FM had viscous modulus (G″) and loss factor (tan δ) values lower than those of CFP, thus reflecting a different viscoelasticity and plasticity. The crystallization and melting temperatures of FM were also different from those of CFP, indicating the presence of a dissimilar polymorphic fat-crystal structure. Nevertheless, the FM containing an oleogel prepared with 5% beeswax and OPO was more similar to CFP. The FA profile of CFP and FM, with 80% polyunsaturated fatty acids (PUFA) and 60% oleic acid, is healthier than that of a PP commercial butter (CB), evidencing that, although improvements in margarine plasticity are still necessary, OPO is technologically viable to produce healthier PP margarines.

Effect of Olive Pomace Oil on Cardiovascular Health and Associated Pathologies

Background: olive pomace oil (OPO) is a nutritionally relevant fat due to its high oleic acid content (C18:1) and the presence of a wide range of minor bioactive components. Although numerous in vitro and preclinical studies have been developed to study some of its characteristic components, the health effect of prolonged OPO consumption is unknown. Methods: a randomised, blinded, cross-over, controlled clinical trial was carried out in 31 normocholesterolemic and 37 hypercholesterolemic subjects. Participants consumed 45 g/day of OPO or sunflower oil (SO) for 4 weeks, each preceded by a 3-week run-in/wash-out phase with corn oil (CO). Results: regular consumption of OPO and SO had no statistically significant effect on any of the markers related to lipid profile, blood pressure, and endothelial function in both groups, except for eNOS levels, which were close to statistical significance due to the effect of oil (OPO and SO) (p = 0.083). A decrease in visceral fat (p = 0.028) in both groups was observed after OPO intake, accompanied by an increment of leptin (p = 0.017) in the hypercholesterolemic group. Conclusion: reducing visceral fat after prolonged OPO intake might contribute to improve cardiometabolic status, with a potentially positive effect on the vascular tone. Further clinical trials are needed to confirm the present results.