Improving oxidative stability of olive oil: Incorporation of Spirulina and evaluation of its synergism with citric acid

The Potential of Phaeodactylum as a Natural Source of Antioxidants for Fish Oil Stabilization

Worldwide, fish oil is an important and rich source of the health-beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). It is, however, troubled by its high susceptibility towards lipid oxidation. This can be prevented by the addition of (preferably natural) antioxidants. The current research investigates the potential of Phaeodactylum carotenoids in this regard. The oxidative stability of fish oil and fish oil with Phaeodactylum addition is evaluated by analyzing both primary (PV) and secondary (volatiles) oxidation products in an accelerated storage experiment (37 °C). A first experimental set-up shows that the addition of 2.5% (w/w) Phaeodactylum biomass is not capable of inhibiting oxidation. Although carotenoids from the Phaeodactylum biomass are measured in the fish oil phase, their presence does not suffice. In a second, more elucidating experimental set-up, fish oil is mixed in different proportions with a Phaeodactylum total lipid extract, and oxidative stability is again evaluated. It was shown that the amount of carotenoids relative to the n-3 LC-PUFA content determined oxidative stability. Systems with a fucoxanthin/n-3 LC-PUFA ratio ≥ 0.101 shows extreme oxidative stability, while systems with a fucoxanthin/n-3 LC-PUFA ratio ≤ 0.0078 are extremely oxidatively unstable. This explains why the Phaeodactylum biomass addition did not induce oxidative stability.

Improving the oxidative stability of virgin olive oil using microformulated vitamin-C

This study aims to improve the oxidative stability of olive oil using microformulated vitamin-C (Vit-C). The microemulsion containing 10,000 µg/ml Vit-C with a droplet size of 1,000 ± 68 nm was first prepared. Free radical scavenging of olive oil and olive oil containing blank microemulsion, different amounts of formulated Vit-C (100-500 µg/ml), and TBHQ (100 and 200 µg/ml as a standard antioxidant) was around 90% during 21 days of incubation at 60°C. The oxidative stability of the mentioned samples during incubation was investigated using the rancimat test, and their quality criteria analysis was studied by peroxide and the acid values. Results showed that the sample's acid value containing 500 µg/ml of Vit-C did not show significant differences (p < .05) with samples containing TBHQ. However, samples containing TBHQ's peroxide value were significant (p < .05) lower than samples containing 500 µg/ml of Vit-C. Furthermore, the induction time of samples containing 500 µg/ml of Vit-C was significantly (p < .05) higher than other treatments during incubation. Thus, the prepared microemulsion could be used as a natural antioxidant in the oil industry instead of harmful synthetic TBHQ.

Improvement of Physico-chemical Properties of Arbequina Extra Virgin Olive Oil Enriched with β-Carotene from Fungi

Nowadays the consumption of essential carotenoids is reduced due to the lower intake of fruits and vegetables, being humans not capable of synthesizing these molecules. β-carotene is one of the most important carotenoids possessing anti-oxidation, anti-inflammation and anti-cancer properties. The aim of this work consists of preparing virgin olive oils enriched in β-carotene from fungi at different concentrations (0.041 and 0.082 mg/mL) in order to obtain new functional foods. Values of quality parameters (free acidity, peroxide value, coefficients of specific extinction and p-anisidine) have been obtained, showing that quality of olive oils was improved. Furthermore, the effect of β-carotene was evaluated as possible oxidative stabilizer during microwave heating and ultra violet-light exposure of the oils. As expected, the enrichment process brought changes in olive oils color, turning them orange-reddish. The use of natural antioxidants, in particular β-carotene could be an effective way to protect virgin olive oils from degradation and is a good strategy also to enhance the consumption of bioactive compounds improving olive oils shelf-life and nutritional value.

Microalgae as source of functional ingredients in new-generation foods: challenges, technological effects, biological activity, and regulatory issues

Microalgae feasibility as food ingredients or source of nutrients and/or bioactive compounds and their health effects have been widely studied. This review aims to provide an overview of the use of microalgae biomass in food products, the technological effects of its incorporation, and their use as a source of health-promoting bioactive compounds. In addition, it presents the regulatory aspects of commercialization and consumption, and the main trends and market challenges Microalgae have stood out as sources of nutritional compounds (polysaccharides, proteins, lipids, vitamins, minerals, and dietary fiber) and biologically active compounds (asthaxanthin, β-carotene, omega-3 fatty acids). The consumption of microalgae biomass proved to have several health effects, such as hypoglycemic activity, gastroprotective and anti-steatotic properties, improvements in neurobehavioral and cognitive dysfunction, and hypolipidemic properties. Its addition to food products can improve the nutritional value, aroma profile, and technological properties, with important alterations on the syneresis of yogurts, meltability in cheeses, overrun values and melting point in ice creams, physical properties and mechanical characteristics in crisps, and texture, cooking and color characteristics in pastas. However, more studies are needed to prove the health effects in humans, expand the market size, reduce the cost of production, and tighter constraints related to regulations.

Evaluation of the oxidative stability of Chipotle chili (

Capsicum annuum L. (Chipotle chili) is a natural source of bioactive metabolites with antioxidant properties. The objective of this research was to obtain and characterize the oxidative stability under storage of Chipotle chili oleoresins extracted with cold-pressed avocado oil. The most efficient conditions obtained to extract carotenoids and phenolic compounds were at 1:3 ratio (chipotle chili: avocado oil; w:v) at room temperature in darkness during 48 h. At the end of the harshest conditions (45 °C, 30 days), the extracts were stable to lipid oxidation with a final Totox value of 27.34, a carotenoid preservation of 85.6%, antioxidant activity retention of 80.66% and a color change (ΔE) of 1.783. The kinetic constants obtained were higher for peroxide formation than for carotenoid degradation. The oleoresins obtained could be considered an economic and sustainable alternative to extract carotenoids with good oxidation stability that could be used in foodstuffs.