Basil (Ocimum basilicum L.) is an annual spicy plant generally utilized as a flavouring agent for food. Basil leaves also have pharmaceutical properties due to the presence of polyphenols, phenolic acids, and flavonoids. In this work, carbon dioxide was employed to extract bioactive compounds from basil leaves. Extraction with supercritical CO2 (p = 30 MPa; T = 50 °C) for 2 h using 10% ethanol as a cosolvent was the most efficient method, with a yield similar to that of the control (100% ethanol) and was applied to two basil cultivars: “Italiano Classico” and “Genovese”. Antioxidant activity, phenolic acid content, and volatile organic compounds were determined in the extracts obtained by this method. In both cultivars, the supercritical CO2 extracts showed antiradical activity (ABTS●+ assay), caffeic acid (1.69–1.92 mg/g), linalool (35–27%), and bergamotene (11–14%) contents significantly higher than those of the control. The polyphenol content and antiradical activity measured by the three assays were higher in the “Genovese” cultivar than in the “Italiano Classico” cultivar, while the linalool content was higher (35.08%) in the “Italiano Classico” cultivar. Supercritical CO2 not only allowed us to obtain extracts rich in bioactive compounds in an environmentally friendly way but also reduced ethanol consumption.
Sourdough is an old example of a natural starter composed of a mixture of flour, water, and metabolites and is produced by naturally occurring lactic acid bacteria and yeasts that influence bread aroma. In this work, four types of sourdough were used to prepare bread: one sourdough with yeast beer and three with bacteria and yeasts. The physicochemical parameters (pH, moisture, water activity, and organic acids) of the bread and sourdoughs were assessed. Lactic, acetic, and succinic acids were found in considerable amounts in sourdoughs and the corresponding breads. The fermentation quotient (molar ratio between lactic and acetic acid) ranged from 0.39 to 3.4 in sourdoughs. Lactic acid was prevalent in all types of bread and showed the highest value in bread made from sourdough with a 1.5 bacteria/yeast ratio (8722.24 mg/kg). Moreover, volatile organic compounds were identified in bread samples. Alcohols, aldehydes, and acetic acid were mainly found. The alcohol concentration ranged from 140.88 to 401.20 ng/g. Aldehydes ranged from 185.01 to 454.95 ng/g, and acetic acid ranged from 91.40 to 173.81 ng/g. Bread prepared from sourdough with a 1.5 bacteria/yeast ratio showed a considerable amount of alcohols and acetic acid.
8 April 2022 in International Journal of Food Science and Technology
This work investigated the extraction of bioactive compounds from citrus peels, an agri‐food waste. Carbon dioxide (CO2), an eco‐friendly solvent, was used under liquid and supercritical conditions to perform the extractions from orange, tangerine and lemon peels. The possibility of using ethanol as a cosolvent at small percentages up to 20% was also studied. The extraction yield, total polyphenolic content, individual polyphenolic profile, antiradical activity and volatile organic compounds of the extracts were evaluated.The highest yields were obtained when 20% ethanol was used as a cosolvent in both liquid (at 20 MPa and 20 °C) and supercritical (at 30 MPa and 60 °C) CO2 extraction. In addition, the extracts obtained with liquid CO2 + 20% ethanol showed the highest content of naringin (35.26, 44.05 and 19.86 mg g‐1 in orange, tangerine and lemon peel extracts, respectively) and terpenes, in particular limonene. This type of extract also showed the highest antiradical activity (31.78–59.51 µmolTE g‐1) as measured by both ABTS·+ and DPPH·.These findings show that the extraction with a liquid CO2 and ethanol mixture could be a valid alternative to traditional solvent extraction using 80% less organic solvent and producing extracts with high antiradical capacity and rich in volatile organic compounds.
28 December 2019 in International Journal of Food Science and Technology
This study evaluated the effect of dietary incorporation of linseed alone or along with dried tomato paste-pepper powder mix on egg physical characteristics, antioxidant profiles, lipid oxidative status, and yolk coloration before and after storage at 4 °C for one month. Sixty Novogen White laying hens, 27 weeks-old, were divided into three groups and given 100 g/hen/day of a standard diet (C), standard diet containing 4.5% of ground linseed (L), linseed diet containing 1% of dried tomato paste and 1% of sweet red pepper (LTP). Linseeds increased (p < 0.05) egg yolk antioxidant capacity but not lipid oxidative stability (p > 0.05). However, dietary inclusion of LTP did not improve fresh egg yolk antioxidant activity and lipid oxidation stability (p > 0.05). With reference to the stored eggs, only antioxidant activity measured by phosphomolybdenum reduction and lipid oxidative stability were influenced (p < 0.05) by the dietary treatment. Fresh egg yolk of hens fed on linseeds tended to have a slightly more yellow, redder, and less light color than the eggs of hens fed with the control diet. Dietary supplementation of LTP increased (p < 0.05) the Roche yolk color fan (RYCF) score and redness (a*) and decreased (p < 0.05) lightness (L*) without affecting (p > 0.05) saturation (C*). Storage of hens’ eggs fed on the control diet did not influence (p > 0.05) yolk color.
19 May 2021 in International Journal of Food Science and Technology
Summary: In this work, the use of supercritical carbon dioxide, a nontoxic solvent, was proposed to extract bioactive compounds from Juglans regia L. green husk and was compared to other traditional techniques based on solvents such as ethanol, methanol and water. Supercritical CO2 was combined with ethanol as an organic modifier at a rate of 20% of the total flow to achieve greater extraction of polar compounds. The extracts were characterised in terms of extraction yields, antioxidant activity, total polyphenol content, phenolic acids, juglone, volatile organic compounds and antifungal activity. The results showed that the extracts obtained with supercritical CO2 were rich in polyphenols (10750 mg GAE/100 g) and juglone (1192 mg/100 g) and exerted high antioxidant activity and antifungal activity compared with the tested fungi. Walnut green husk is not just a food industry waste but also an important economic source of bioactive compounds that could be used for food active packaging.