Seeds cold pressing

The fruits of pomegranate (Punica granatum, L. Punicaceae) are popular in the East and far East countries. The dried pericarp has been utilized in folk medicine for colic, colitis, diarrhea, dysentery, leucorrhea, menorrhagia, oxyuriasis, paralysis and rectocele. The flavonoid extract from cold pressed seed oil showed 31-44% inhibition of sheep COX-1 enzyme and 69-81% inhibition of soybean lipoxygenase [181]. 

Microstructures of the two GPS-ed silicon nitride materials (a) SN-F (not seeded, cold pressed), (b) SN-C (seeded, tape cast). Plasma etching highlights the epitaxial growth of P-sialon on P-Si3N4 cores (indicated by the arrows). 

Oils can be extracted from raw or roasted seeds. The best grade oil coming from cold pressing and filtering. Most sesame oils are practically odourless with a pale yellow colour. Usually blended with other carriers, as it is a thicker... 

Oil expressed without heating contains the least amount of impurities and is often of edible quality without refining or further processing. Such oils are known as cold-drawn, cold-pressed, or virgin oils. The expressed oil from cooked seeds contains greater quantities of nonglyceride impurities such as phospholipids, color bodies, and unsaponifiable matter. Such oils are highly colored and are not suitable for edible use. 

Many species in the Europhorbiaceae and Labiatae families produce seeds with a high content of oil and contribution of hnolenic acid of up to 76% (1). Flaxseed has been used for years in the production of paints, varnishes, inks, and linoleum. In food applications, flaxseed is more often used than oil because of its better stability and because of the presence of fiber, lignans, and a-linolenic acid (ALA), which have health benefits. Cold pressed flaxseed oil is not considered suitable for deep-frying, although Chinese use it in stir-frying (2). In this chapter, oilseeds of flax, perilla, camelina, and chia are discussed as sources of oils with elevated content of ALA. These oilseeds are produced in industrial quantities and can be considered as potential sources of new oils with specific nutritional and functional properties. 

Sesame oil from roasted sesame seed has the characteristic flavor and color of the roasted sesame oil the filtered crude oil is used without further refining. Sesame oil from cold-pressed unroasted sesame seed is also used directly after filtration as a flavored oil. Crude sesame oil from unroasted sesame seeds after screw-press or hydraulic press or solvent extraction, which varies in color from yellow to dark amber, may need further refining. Refined sesame oil is usually pale yellow in color. 

The procedures used for the extraction and processing of sunflower oil are broadly the same as for other seed oils. Focus will be made on those operations or details specific of the production of sunflower oil. Sunflower oil is usually extracted through pressing of seed and later extraction by solvent. The crude oil is usually subjected to traditional refining stages. Otherwise, cold-pressed sunflower oil is currently valued as a new extra virgin oil. 

Content and Composition of Sunfiower OH Wax Both the wax content and composition of sunflower oil depend on the method of oil extraction. According to work carried out by CareUi et al. (53) with sunflower oils extracted from the same seed lot, the crude industrial oil obtained by hexane extraction contained 1073 ppm, the crude industrial oil obtained by hot pressing contained 947 ppm, and the cold-pressed oil obtained in the laboratory had 771 ppm of wax. That is, the oil extracted by hexane had the highest wax content, the hot-pressed oil having a higher content than the cold-pressed oil. 

Virgin oils currently available on the market are not restricted to virgin olive oil but include other oils obtained by cold pressing of seed. These oils are appreciated highly by consumers in view of their nutritional characteristics and flavor (particularly those organoleptic notes that are lost in refined oils). The consumer appreciates the natural characteristics of these oils, as they are not subjected to chemical treatment. A relatively new market has developed for these oils in the U.K., Germany, France, Italy, and Switzerland, among other markets. Sunflower oil is manufactured and commercialized as cold-pressed or first cold-pressed oil. 

There is considerable interest in the chemical composition and properties of citrus oils and essences as well as the role they play in food and nonfood industries. Citrus peel oils and essences possess a pleasant aroma, with oxygenated compounds being the major constituents that account for their characteristic odor. Terpenes, the most abundant components in cold-pressed citms peel oil, are removed in concentrated oil production, usually by use of adsorbant and supercritical carbon dioxide, to increase the concentration of oxygenated compounds and to enhance the qualification of the oil. Meanwhile, citms seed oils are composed largely of triacylglycerols and are rich in oleic and linoleic acids. 

The fatty acid profile of two cold-pressed black raspberry seed oils demonstrated high concentrations of both n-3 and total unsaturated fatty acids. The concentration of ot-linolenic acid (18 3n-3) was 35% of total fats, and unsaturated fatty acids comprised 98-99% (Table 1). Linoleic acid was the predominant fatty acid (Table 1) however, the ratios of n-6 to n-3 fatty acids were very low at 1.6 1. The other measurable fatty acids included oleic (18 ln-9) and palmitic (16 0) acids (Table 1). The overall fatty acid composition of black raspberry seed oil was very similar to red raspberry seed oil (1) (Table 1). 

Red raspberry seed oils, extracted by either hexane (2) or cold-pressing (3), were examined for their fatty acid compositions. Both methods detected very similar... 

In 2004, Parry et al. (3) examined the chemical composition and physicochemical properties of cold-pressed marionberry seed oil. The oil was shown to contain a relatively high percentage of n-3 fatty acids in the form of a-linolenic acid (15.7%) (Table 1). This amount was lower than that of other caneberry seed oils, including black raspberry, red raspberry, and boysenberry seed oils, tested under the same conditions. The n-6 to n-3 fatty acid ratio was 4 1, which was the highest among the tested caneberry group. 

The cold-pressed blueberry seed oil investigated by Parry and Yu. (3) demonstrated a high concentration of n-3 fatty acids. Alpha linolenic acid was the sole source of the n-3 and comprised 25.1 % of the total fatty acids (Table 1). The ratio of n-6 to n-3 fatty acids was 1.7 1. Linoleic acid (18 2n-6) was the most prevalent fatty acid in the blueberry seed oil followed by a-linolenic, oleic, palmitic (16 0), and stearic (18 0) acids (Table 1). The blueberry seed oil also showed a significantly higher antioxidant capacity compared with marionberry, black raspberry, cranberry, and pumpkin seed oils using the oxygen radical absorbance capacity (ORAC) test. Therefore, blueberry seed oil may serve as an excellent dietary source of n-3 fatty acids and natural antioxidants. 

Several studies have confirmed that the seed oil from the North American variety of cranberry contains significant levels of a-linolenic acid. In a U.S. patent, Heeg et al. (4) reported the a-linolenic acid content of cranberry seed oil to be between 30% and 35% of total fatty acids. In 2003, Parker et al. (5) found 22.3% a-linolenic acid in the cold-pressed cranberry seed oil, and in 2004, Parry et al. (3) determined the oil to contain 32.0% a-linolenic acid from two different lots of the seed oil. The ratios of n-6 to n-3 fatty acids in all were low from 1.2 1 to 2 1. Also, all of the studies documented similar ratios among the rest of the common fatty acids found in cranberry seed oil, including, in order of higher amount present linoleic, oleic, palmitic, stearic, and eicosadienoic (20 2) acids (Table 1). In addition to a-linolenic acid, cranberry seed oil is rich in natural antioxidants (8). These antioxidants may directly react with free radicals and prevent lipid oxidation in human low-density lipoprotein. 

Onion Allium cepa) seeds contained about 23.6% crude fat. The seed oil was analyzed for its chemical composition. The onion seed oil contained 44.6% linoieic acid and 34.3% oleic acid (Table 6) (38). The total unsaturated fatty acids comprised of 79% of the oil. A greater concentration of linoieic acid was determined in the cold-pressed onion seed oil obtained from Botanical Oil Co. (Spooner, Wl). Linoieic acid accounted for 63.7% of total fatty acids, and oleic acid ranged from 26.7-30.1%. The total unsaturated fatty acids were about 90% (3). In summary, onion seed oil may serve as a dietary source of essential n-6 fatty acid and oleic acid. 

The seeds of M. oleifera variety Mbololo yielded 26%, 31%, and 36% crude oil by cold-pressing, hexane extraction, and chloroform-methanol extraction (1 1, v/v), respectively (70). The seed oil was rich in total monounsaturated fatty acids and contained 74—75% oleic acid (Table 9). The total saturated fatty acids were... 

Derivation From the seeds of the castor bean, Ricinus communis (Brazil, India, the former U.S.S.R., U.S.). They are cold-pressed for the first grade of medicinal oil and hot pressed for the common qualities, approximately 40% of the oil content of the bean being obtained. Residual oil in the cake is obtained by solvent extraction. Chief constituent Ricinolein (glyceride of ricinoleic acid). 

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