Obtaining oil from macauba kernels by ultrasound-assisted extraction using ethyl acetate as the solvent

Production of Protein Concentrates from Macauba (Acrocomia aculeata and Acrocomia totai) Kernels by Sieve Fractionation

Macauba palm fruits (Acrocomia aculeata and Acrocomia totai) are emerging as sources of high-quality oils from their pulp and kernels. The protein-rich macauba kernel meal (MKM) left after oil extraction remains undervalued, mainly due to the lack of suitable deoiling parameters and integrated protein recovery methods. Therefore, the present study aimed to produce protein concentrates from MKM using sieve fractionation. The deoiling parameters, comprising pressing, milling, and solvent extraction, were improved in terms of MKM functionality. The combination of hydraulic pressing, milling to 1 mm, and the hexane extraction of A. aculeata kernels resulted in MKM with the highest protein solubility (77.1%), emulsifying activity index (181 m²/g protein), and emulsion stability (149 min). After sieve fractionation (cut size of 62 µm), this meal yielded a protein concentrate with a protein content of 65.6%, representing a 74.1% protein enrichment compared to the initial MKM. This protein concentrate showed a reduced gelling concentration from 8 to 6%, and an increased emulsion stability from 149 to 345 min, in comparison to the MKM before sieving. Therefore, sieve fractionation after improved deoiling allows for the simple, cheap, and environmentally friendly recovery of MKM proteins, highlighting the potential of macauba kernels as a new source of protein.

Ultrasound-assisted extraction of oil from hempseed (Cannabis sativa L.): Part 1

BACKGROUND

Ultrasound-assisted extraction of the intermediate product from the mechanical expression of hemp (Cannabis sativa L.) seed oil was investigated to improve the overall expression yield without compromising oil quality. Complementary ultrasound technology was used as an out-of-line treatment carried out at 20 kHz frequency and optimized with respect to amplitude (80 and 152 μm), sonication time (2, 10, 20 min) and to the hemp paste properties, in particular its particle size and hydration, which drive the compressibility of the press cake.

RESULTS

Under the conditions evaluated, the optimal ultrasound treatment was found to be the one applied on the hydrated press cake for 2 min at 152 μm, which resulted in an oil yield of 13.4%, with an increase in extraction efficiency equal to 73% with respect to the control (untreated press cake). Sonication had a positive effect on the press cake texture and on the extracted oil antioxidant activity. Soaked samples treated for 2 min at 152 μm yielded the lowest hardness. Oil recovered from soaked samples treated at 80 μm and 152 μm ultrasound for 2 min had the highest antioxidant capacity.

CONCLUSIONS

The technological results gathered in the present investigation are preliminary to the design and engineering of scaled-up equipment that combines the mechanical screw expression and the in-line ultrasound unit. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sonication, a Potential Technique for Extraction of Phytoconstituents: A Systematic Review

Traditional extraction techniques have lost their optimum performance because of rising consumer demand and novel technologies. In this regard, several techniques were developed by humans for the extraction of plant materials from various indigenous sources, which are no longer in use. Many of the techniques are not efficient enough to extract maximum plant material. By this time, evolution in extraction has led to development of various techniques including microfiltration, pulsed electric fields, high pressure, microwave assistance, enzyme assistance, supercritical fluid, subcritical fluid and ultrasonication. These innovations in food processing/extraction are known as “Green Food Processing”. These technologies were basically developed by focusing on three universal parameters: simplicity, energy efficiency and economy. These green technologies are practical in a number of different food sectors, mostly for preservation, inhibition of microorganisms, inactivation of enzymes and extraction of plant material. Like the others, ultrasonication could also be used for the said purposes. The primary objective of this review is to confine the potential use of ultrasonication for extraction of oils, pectin and phytochemicals by reviewing the literature systematically.

Passion fruit seed oil: extraction and subsequent transesterification reaction

This work aims to remove the oil from passion fruit seeds using ethanol as solvent and then to carry out the transesterification of the product from the extraction step (oil + ethanol). The effects of operational variables in the ultrasound-assisted extraction (UAE) were evaluated and traditional extraction was performed for comparison. The extraction product was directed to the reaction step using an enzymatic catalyst. UAE provided oil yield from 12.32 to 21.76%, and the maximum value (73.7% of the traditional extraction yield) was obtained at 60 °C and 50 min using a solvent-to-seed ratio of 4. Oil removal was favored by increases in the investigated variables. g-tocopherol, δ-tocopherol and a high concentration of polyunsaturated fatty acids were identified in the oils. The oil obtained by UAE presented higher phytosterol contents. From the reaction step, samples were obtained with higher concentrations of ethyl esters, in addition to emulsifiers (diglycerides and monoglycerides).

Brazilian fruits of Arecaceae family: An overview of some representatives with promising food, therapeutic and industrial applications

The Arecaceae family is widely distributed and comprises about 2600 species, in which 48 of them are native to Brazil and occurs in transition biomes between the Amazon, Cerrado and Caatinga. In addition to being used as a source of food and subsistence, they are also rich in lipophilic bioactive compounds, mainly carotenoids, polyunsaturated fatty acids, tocopherols and vitamin A. Moreover, they have considerable content of phenolic compounds, fibers and minerals. Therefore, the objective of this review is to present the physical-chemical and nutritional aspects, the main bioactive compounds, the biological properties and the innovative potential of four Brazilian palm-tree fruits of the Arecaceae family. Due to the presence of bioactive compounds, these fruits have the potential to promote health and can be used to prevent chronic non-communicable diseases, such as obesity, type 2 diabetes and others. Furthermore, these raw materials and their by-products can be used in the development of new food, chemical, pharmaceutical and cosmetic products. To ensure better use of these crops, promote their commercial value, benefit family farming and contribute to the country's sustainable development, it is necessary to implement new cultivation, post-harvest and processing techniques. Investing in research to publicize their potential is equally important, mainly of the ones still little explored, such as the buritirana.