Macadamia Oil Extraction With Alcoholic Solvents: Yield and Composition of Macadamia Oil and Production of Protein Concentrates From Defatted Meal

Abstract

The aim of this study is to evaluate the performance of ethanol and isopropanol in the extraction of macadamia oil and the production of protein concentrates from the defatted meal. Partially defatted macadamia cake is submitted to batch extractions in one stage of contact at 60, 75, and 90 °C, while the sequential extraction trials considering four stages are performed at 75 °C. Oil extraction yield is influenced by the solvent type, temperature, and pre‐treatment of the material. Absolute isopropanol at 90 °C enables to extract 66% of the oil while in the sequential configuration, oil yield up to 96% is attained after four stages. The retention of the solution adhered to the fiber (liquid holdup, LH) is affected by the type of solvent and characteristics of the raw material, being obtained LH values higher than 2. The oil extraction conditions affect negatively on the nitrogen solubility index of the defatted meal. The solvents in absolute degree impact less on the solubility of the proteins, enabling the production of macadamia protein concentrates (protein content of 70%) with functional properties suitable for using in the food industry. Practical Applications: This study is useful to oilseed processors and researchers because it addresses the issue of using macadamia cake as raw material to oil extraction with alcoholic solvents, ethanol, and isopropanol, which are less flammable and toxic than hexane. In addition, it is evaluated the effect of process variables on the oil yield, liquid holdup, and characteristics of the extraction products (oil and defatted meal). The results of this work could help to develop macadamia oil extraction process safe for the workers of oil industry and consumers and, simultaneously, to enable the use of by‐products (defatted meal) in the protein concentrates production. Macadamia oil extraction, from partially defatted macadamia cake, is carried out using ethanol and isopropanol (absolute and hydrated) as solvents. The products of macadamia oil extraction are characterized, thus the extracted oils show typical fatty acid composition and the defatted meal presented higher protein content than raw material. Therefore, from these defatted meals are produced macadamia protein concentrates, which show good functional properties to be used as food ingredients.

The Chromosome-Scale Reference Genome of Macadamia tetraphylla Provides Insights Into Fatty Acid Biosynthesis

“…Macadamia kernels are rich in unsaturated fatty acids, essential amino acids, trace elements, and vitamins, but monounsaturated fatty acids and palmitoleic acid contents are extremely high ( Kaijser et al, 2000 ). Macadamia nuts are eaten directly or used as raw material for processing high-grade edible oil ( Navarro and Rodrigues, 2018 ). Macadamia nuts are very nutritious and deeply subjected to a large consumer approbation fancy, to whom it is also known as the “Queen of nuts.” Long-term consumption of macadamia lowers blood cholesterol and viscosity of platelets, prevents arteriosclerosis, reduces heart disease, myocardial infarction, and other cardiovascular diseases ( Garg et al, 2003 ; Garg et al, 2007 ), World consumption of macadamia nuts has rapidly grown in recent years with more than 400,000 tons in demand (FAO statistics, year), yet the current global supply is only ∼40,000 tons.…”

Genome assembly and annotation ofMacadamia tetraphylla

“…The kernel of macadamia are rich in unsaturated fatty acids, essential amino acids, Trace elements and vitamins, the content of monounsaturated fatty acids and palmitoleic acid are also extremely rich [9][10][11] . Macadamia nuts can be eaten directly, also can be used as raw material for processing high-grade edible oil 12 . Because it is very nutritious, long-term consumption of macadamia helps to lower blood cholesterol, prevent arteriosclerosis, lowering the viscosity of platelets, reduce the incidence of heart disease, myocardial infarction and other cardiovascular diseases 13,14 , therefore, the macadamia nuts were favored by consumers, known as the "Queen of nuts.…”

“…The adaptors were removed, low-quality and N base reads were trimmed. The reads were cut when the average quality per base drops below 15 with a 4-base wide sliding window 12.…”

Extração de óleo de amêndoas de baru via solventes alcoólicos: avaliação da composição do óleo, das alterações proteicas e estudo da recuperação do solvente

“…Desta maneira, a proposta de substituição do solvente hexano por outros solventes alternativos, tais como os solventes alcoólicos, torna-se atrativa sob o ponto de vista toxicológico, ambiental e industrial (JOHNSON e LUSAS, 1983;ZHANG et al, 2002;GANDHI et al, 2003;SETH et al, 2010;RODRIGUES e OLIVEIRA, 2010;SAWADA et al, 2014;NAVARRO et al, 2016;SCHARLACK et al, 2017;NAVARRO e RODRIGUES, 2018) com o intuito de proporcionar maior segurança de processo e obter um alimento adequado para o consumo humano e animal, uma vez que o hexano apresenta como desvantagens inflamabilidade e toxicidade.…”

“…Para cada experimento de extração realizado foram monitorados os teores de água e de solvente referentes à fase extrato e os teores de óleo, de proteína e de solvente referentes à fase rafinado conforme segue. (Sawada et al, 2014;Navarro et al, 2016Navarro et al, , 2018Scharlack et al, 2017). De acordo com Wlsniak et al (1987) o índice de retenção define a quantidade de calor necessária para a dessolventização da fase rafinado, ou seja, fases rafinado com menores índices de retenção requerem menos energia para serem dessolventizadas (ZHANG et al, 2002).…”