Debittering of cold pressed grapefruit seed oil by metal‐organic framework adsorbents

Abstract

The aim of this study was to remove bitterness from cold pressed grapefruit seed oil. Seven different metal‐organic frameworks and three natural clays (commercial bleaching earth, zeolite, and sepiolite) were used as adsorbents. In addition, water washing and solvent extraction treatments were done. After the treatments, oil physicochemical properties, fatty acid, sterol, tocopherol and flavonoid compositions, sensory flavor profile analysis, and consumer tests were completed. Results indicated that adsorbent treatments were better for oil color, turbidity, free fatty acidity, and p‐anisidine values than those of the washing and extraction treatments. Although there was no significant change in oil fatty acid and sterol composition, some loss in tocopherol content was observed after the treatments. Sensory descriptive analysis indicated that oil bitterness, spicy, and throatcatching scores decreased by 62.79%, 42.42%, and 58.97% by chromium metal‐organic framework (Cr‐MOF) treatment. In conclusion, Cr‐MOF treatment successfully removed the bitterness from cold pressed grapefruit seed oil. Practical applications The bitter taste of cold pressed grapefruit seed oil was almost totally removed by adsorbent treatment with the laboratory synthesized chromium metal‐organic frameworks. Sensory flavor profile analysis and consumer test indicated that the treated oil can be directly consumed as edible oil. This method could have practical importance for those who interested to produce and use cold pressed grapefruit seed oils for edible purposes.

Cold‐pressed flaxseed oil by‐product as a new source of fat replacers in low‐fat salad dressing formulation: Steady, dynamic and 3‐ITT rheological properties

“…Since cold‐pressed oils are not subjected to heat treatment and chemical applications such as refining and solvent extraction, their nutritional components and sensory properties change much less than refined oils (Yilmaz & Ege, 2020). After the cold‐press process, oil and water are removed, and the by‐products with high nutritive components mainly composed of protein and carbohydrate occur (Srikaeo, Poungsampao, & Phuong, 2017).…”

Silica gel 60 removes bitterness from cold‐press produced grapefruit seed oil by adsorption principle

“…It was indicated that this activation process both enhances their active surfaces and increases their affinities. 9,10 Kaolin and halloysite were activated by the acid-washing process.…”

“…The fatty acid composition of the control and treated oil samples was determined according to our previous studies with a gas chromatography (Agilent 7890B, Agilent Technologies, Palo Alto, CA, USA) equipped with HP 88 capillary column (100 m × 0.25 mm, 0.2 µm), Agilent G4513A autosampler, and flame ionization detector. [9][10][11] Detail of the technique could be reached from the publications. [9][10][11] Similarly, the sterol composition of the samples was measured following our previous studies just cited above with the same gas chro-…”

“…Because it was not a complete bitterness removal, we took another adsorption study carried out with seven laboratory synthesized metal-organic frameworks (MOFs) and three natural clays (commercial oil bleaching earth, zeolite, and sepiolite) as adsorbents. 10 Sensory analysis results proved that oil bitterness, spicy, and throat catching scores were reduced around 62.79%, 42.42%, and 58.97% by chromium MOF adsorbent as the best achievement.…”

“…Accordingly, the bitter compounds found in the cold-pressed grapefruit seed oil (CPGSO) were stated as naringin, poncirin, neohesperidin, and neoeriocitrin. [6][7][8][9][10] As virgin oil, CPGSO was produced and characterized in our laboratory. 11 Naringinase and hesperidinase enzymes were preincubated with ground grapefruit seed meal before cold-pressing against control, and all oil characterization analyses, including flavonoid composition analysis and sensory tests, were completed.…”