Avocado oil has generated growing interest among consumers due to its nutritional and technological characteristics, which is evidenced by an increase in the number of scientific articles that have been published on it. The purpose of the present research was to discuss the extraction methods, chemical composition, and various applications of avocado oil in the food and medicine industries. Our research was carried out through a systematic search in scientific databases. Even though there are no international regulations concerning the quality of avocado oil, some authors refer to the parameters used for olive oil, as stated by the Codex Alimentarius or the International Olive Oil Council. They indicate that the quality of avocado oil will depend on the quality and maturity of the fruit and the extraction technique in relation to temperature, solvents, and conservation. While the avocado fruit has been widely studied, there is a lack of knowledge about avocado oil and the potential health effects of consuming it. On the basis of the available data, avocado oil has established itself as an oil that has a very good nutritional value at low and high temperatures, with multiple technological applications that can be exploited for the benefit of its producers.

This research focused on obtaining eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) (EPA+DHA) concentrates from refined commercial salmon oil (RCSO). Independent variables of the complexation process were optimized by means of the application of response surface methodology (RSM) in order to obtain the maximum content of such fatty acids (FAs). As a result of employing the optimized conditions for all the variables (6.0, urea:FA content ratio; −18.0 °C, crystallization temperature; 14.80 h, crystallization time; 500 rpm, stirring speed), high contents of EPA and DHA could be obtained from RCSO, achieving increases of 4.1 and 7.9 times in the concentrate, with values of 31.20 and 49.31 g/100 g total FA, respectively. Furthermore, a 5.8-time increase was observed for the EPA + DHA content, which increased from 13.78 to 80.51 g/100 g total FA. It is concluded that RCSO can be transformed into a profitable source of EPA and DHA (EPA+DHA), thus leading to a product with higher commercial value.

Stevia (Stevia rebaudiana Bert.) is a relevant source of natural phenolic compounds with antioxidant and antimicrobial properties. The aim of this study was to evaluate the potential protective effect of crude stevia extracts on the quality and shelf‐life of salmon (Salmo salar) paste. For this, polyphenol extracts obtained by water extraction, ethanol/water extraction and supercritical CO2 with ethanol extraction were evaluated in preserving salmon paste. Salmon paste was stored under refrigerated conditions (5°C) for 21 days, being primary, secondary, and total lipid oxidations monitored along storage by means of peroxide, p‐anisidine, and TOTOX indices, respectively. In addition, ω3/ω6 ratio, polyene index, and α‐tocopherol were monitored. Microbiological analysis comprised the investigation of aerobic mesophiles and psychrotrophes. Salmon paste samples treated with ethanol/water and supercritical CO2‐ethanol stevia extracts exhibited the highest (p < 0.05) ω3/ω6 ratio and α‐tocopherol content. Besides, partial inhibition of both primary and secondary lipid oxidation events and aerobes and psychrotroph growth was also observed in both samples. These results correlated with the fact that ethanol/water and supercritical CO2‐ethanol extracts provided the highest DPPH and FRAP values. These results open the way to the utilization of bioactive compounds from stevia leaves for the preservation of foods derived from salmon. Practical applications: The results obtained in this research show the possibility of using stevia and/or its derivatives of the sweetener industry as an alternative source of natural antioxidants in refrigerated fatty fish paste. The results indicate that it is possible to obtain advantages in the refrigerated salmon paste, based on the use of some extracts of stevia, which can help to inhibit lipid oxidation and development of pathogenic microorganisms. Further studies on the use of stevia and its derivatives should focus on the application of clean separation technologies such as supercritical fluid extraction. Stevia extracts obtained by extraction with water (W), ethanol‐water mixture (E/W, 50:50 v/v) and extraction with supercritical CO2 and ethanol (SCE; scCO2/E, 95: 5 v/v) previously elimination of the steviosides demonstrates a conservative effect of refrigerated salmon paste. The SCE and E/W extracts provides better control of primary and secondary lipid oxidation compounds and moderate inhibition of aerobes and psychrotrophs.

Salmon paste contains nutritious components such as essential fatty acids (EPA, DHA), vitamin E and astaxanthin, which can be protected with the addition of red algae extracts. Phenolic extracts were prepared with an ethanol: water mixture (1:1) from the red seaweeds Gracilaria chilensis, Gelidium chilense, Iridaea larga, Gigartina chamissoi, Gigartina skottsbergii and Gigartina radula, obtained from the Pacific Ocean. Most algae had a high content of protein (>7.2%), fiber (>55%) and β-glucans (>4.9%), all expressed on a dry weight basis. Total polyphenols (TP), total flavonoids (TF), antioxidant (DPPH, FRAP) and antibacterial power of the extracts were measured. In addition, the nutritional components of the algae were determined. Results showed that the content of TP in the six algae varied between 2.6 and 11.3 mg EAG/g dw and between 2.2 and 9.6 for TF. Also, the extracts of G. skottsbergii, G. chamissoi, G. radula and G. chilensis showed the highest antiradical activity (DPPH, FRAP). All samples exhibited a low production of primary oxidation products, and protection of the essential components and the endogenous antioxidants tocopherols and astaxanthin, particularly in the case of G. skottsbergii, G. chamissoi, G. radula and G. chilensis. Furthermore, all algae had inhibitory activity against the tested microorganisms, coincident with their antioxidant capacity. Results show that the extracts may have future applications in the development and preservation of essential dietary components of healthy foods.

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