Distribution Of Phytosterols Research Articles

Steam explosion pretreatment enhances free/combined phytosterol extraction and utilization in rapeseed (Brassica napus L.) and its processed products: Insights from SPE-GC approach

The study investigates the impact of steam explosion pretreatment on the distribution of free and combined phytosterols within rapeseed and its derived products. Utilizing solid phase extraction-gas chromatography (SPE-GC) analysis, we elucidated the composition and distribution of phytosterols in five rapeseed varieties and their corresponding processed oils and cakes. The results indicated that Zhongyou 516 and Xiwang 988 are richer in combined phytosterols, whereas Dadi 199, Zhongyouza 501, and Xiwang 291 have a greater concentration of free phytosterols. Steam explosion pretreatment significantly increased the extraction proportion of combined phytosterols in rapeseeds. Throughout the oil process, more than half of the total phytosterol content, specifically 57.0%, was transferred from the steam explosion-treated rapeseed into the rapeseed oil. The variety Xiwang 291 showed the highest efficiency in this transfer, achieving a rate of 61.7%. The study provides crucial data for the enhancement of rapeseed processing techniques and the efficient utilization of phytosterols. Moreover, the study highlights the potential use of the ratio of free to combined phytosterols as a discriminator for different rapeseed oil varieties, offering valuable insights for quality assurance and product differentiation in the industry.

Phytosterols in edible oil: Distribution, analysis and variation during processing

Phytosterols, which are naturally occurring in plants, have excellent nutritional and health values on lowering both the blood cholesterol level and the risk of cardiovascular diseases. Edible oils are the main source of daily intake of phytosterols, whereas the properties of phytosterols may vary a lot depending on their sources. During the processing of edible oil including refining and frying, phytosterol's content fluctuates, which influences the properties of the final product. Phytosterols and their derivatives undergo physical migration between different phases and chemical conversion during the processing, which reduces the quality and the commercial value of edible oils. Therein, the loss of phytosterols is the major concern in the process of neutralization and deodorization. In addition, oxidation and thermal degradation of phytosterols occur simultaneously during frying, which also reduces the content of phytosterols. Nevertheless, the oil matrix has a promoting or an inhibitory effect on the thermal oxidation of phytosterols. Therefore, various efforts have been devoted to analyzing and improving the remaining contents of phytosterols in edible oil. Regardless of the processing method, temperature plays an important role in the loss of phytosterols. At present, the main analysis methods of phytosterols include gas chromatography and liquid chromatography, in which the pretreatment of different types of phytosterols is also a crucial step. This review focused on the following topics comprehensively: (i) the distribution of phytosterols in the oil-containing plants and edible oils during the refining processing; (ii) the pretreatment and analysis methods of various phytosterols (free phytosterols, phytosteryl fatty acid esters, phytosteryl glycosides and acylated phytosteryl glycosides); (iii) the variation of phytosterols in process of esterification and oxidation, storage and so on. The study also proposed that the investigation in the loss and safety of phytosterols during processing of the vegetable oils should be proceeded further in combination with efficient and accurate chromatography methods.

Rheological and physical properties of yogurt enriched with phytosterol during storage.

Phytosterols enriched products are innovative types of functional foods, in which dairy products, like low fat yogurt are ideal vehicles for this functional component. In this study, phytosterol dispersions were prepared using an oil/water (O/W) emulsion. The emulsion was added to yogurt milk. pH, titratable acidity (TA), syneresis, firmness and apparent viscosity of enriched yogurt were determined during storage. Moreover, phytosterols distribution in different parts of enriched yogurt was studied. Results indicated that in enriched yogurt, apparent viscosity and syneresis were lower and firmness was higher compared to the control. Addition of phytosterol to the yogurt had significant effect on acidity. Distribution of phytosterols in different parts of one sample was not uniform. Sensory results showed that there was no significant difference between enriched and control on texture, appearance, flavor and overall acceptance.

Physico-chemical characteristics and nutraceutical distribution of crude palm oil and its fractions

Crude palm oil (CRPO) was dry fractionated at 25 °C to get crude palm olein (CRPOL, 77%) and crude palm stearin (CRPS, 23%). Low and high melting crude palm stearin (LMCRPS 14.3% and HMCRPS 8.7%) were separated by further fractionation of CRPS with acetone. The physico-chemical parameters and nutraceutical distribution showed variation in different fractions. The CRPO contained 514.7 mg·Kg −1 of β-carotene and 82.6%, 16.1%, 12.5% and 3.1% of it was distributed in CRPOL, CRPS, LMCRPS and HMCRPS respectively. The distribution of phytosterols in fraction was 1870.2, 1996.8, 1190.9, 1290.4 and 115.4 mg·Kg −1 for CRPO, CRPOL, CRPS, LMCRPS and HMCRPS respectively. Total tocopherol composition was 535.5, 587.1, 308.0, 305.6 and 36.2 mg·Kg −1 for CRPO, CRPOL, CRPS, LMCRPS and HMCRPS respectively. The results show that the fractionation of CRPO may be helpful in the preparation of nutraceutical-rich fractions.

Distribution of phytosterols in plasma and liver of rats nourished by different routes and effects on liver function

Distribution of phytosterols in plasma and liver of rats nourished by different routes and effects on liver function

The composition and distribution of phytosterols in Digitalis purpurea L.

The composition and distribution of phytosterols in Digitalis purpurea L.

New Sources of Oilseeds from Latin American Native Fruits

Three Latin American oilseeds obtained from native fruits: nopal (tuna) ( Opuntia ficus-indica), cherimoya (chirimoya) ( Annona cherimola), and papaya, Chilean variety ( Carica pubescens or C. candamarcensis) were studied for their fatty acid composition and bioactive compounds, such as tocols and phytosterols, looking for new sources of special oilseeds for this region. The results indicated that each species represents an interesting possibility. Nopal oilseed is a good source of linoleic acid (62%), with a good balance between SFA and MUFA (1:1.3). Cherimoya oilseed presents quite a different composition, with 24% SFA, 43% MUFA and 33% PUFA. Palmitic and stearic acids (15% and 7.6%, respectively) are the main SFA. A good balance between oleic acid (42.7%) and linoleic acid (31%) was observed. Papaya oilseed is a highly MUFA oil (72% with 71% oleic acid), with a very interesting composition, according to the new nutritional and technological recommendations. With respect to bioactive compounds, the main tocol in these three oilseeds was γ-tocopherol, with 136, 300 and 317 mg/kg for cherimoya, papaya and nopal oilseeds, respectively. According to the total tocol content, papaya oilseed presented the highest value with 384 mg/kg. The total amount and distribution of phytosterols was different, with values of 3092, 3554 and 5474 mg/kg for nopal, cherimoya and papaya oilseeds, respectively, with β-sitosterol forming 47.6%, 65.0 % and 78.7% of the total phytosterol fractions, respectively. From the results obtained, Chilean papaya oilseed can be considered as a very promising new source of special plant oil for different applications, followed by cherimoya and nopal oilseeds.

Distribution and retention of phytosterols in frying oils and fried potatoes during repeated deep and pan frying

The retention and distribution of phytosterols in fried oils and French-fries during eight successive pan- and deep-frying sessions of pre-fried potatoes in sunflower oil, palm oil, cottonseed oil, virgin olive oil and a vegetable shortening were evaluated. Phytosterols (β-sitosterol, campesterol, stigmasterol, Δ5-avenasterol) were determined in the unsaponifiable fraction of frying oils and lipids extracted from French-fries by GC/FID after derivatization to trimethylsilyl ethers. French-fries were enriched with phytosterols due to the absorption of frying oil, with β-sitosterol predominating in both fried oils and potatoes. The amount of phytosterols decreased during frying, their overall retentions reaching 9.5–22.8% and 29.4–51.2% after eight successive pan- and deep-frying sessions, respectively, while their deterioration was found to be affected by frying time, frying technique, being more prolonged during pan-frying, and by the oils’ unsaturation, being more extended in polyunsaturated oils. Phytosterols were more or less uniformly distributed between the fried oil and the fried potatoes. The phytosterols dietary intake by consuming potatoes fried in the oils tested is discussed.

Possible alternative utilization of Cynara spp. : II. Chemical characterization of their grain oil

The grain oils extracted from six genotypes of Cynara species: two globe artichokes ( Cynara scolymus L.), two cultivated cardoons ( C. cardunculus L. var. altilis DC.) and two wild cardoons ( C. cardunculus L. var. sylvestris Lam.), were analysed in order to ascertain their alimentary value. Oil yield, moisture, acidity, peroxide number, UV spectrophotometry and CIE colour parameters, fatty acids, phytosterols and α-tocopherol were determined by standard methods. Cynara species which are most promising in terms of quality and quantity of oil were the cardoons, especially those belonging to the wild cardoon genotypes. Triacylglycerols were the dominant constituents together with very little amounts of phospholipids and glycolipids. The high content of oleic and linoleic acids in a balanced ratio, and the low amount of free acids, peroxides, saturated and linolenic acids ensure a good alimentary quality. Distribution of phytosterols was typical of oil from grain of Asteraceae such as sunflower and safflower. Moreover the optimal α-tocopherol content offers a guarantee of stability against oxidation.