Oligosaccharide Content and Composition of Legumes and Their Reduction by Soaking, Cooking, Ultrasound, and High Hydrostatic Pressure

Abstract

Oligosaccharides, including raffinose, stachyose, ciceritol, and verbascose, are commonly found in legumes and often result in flatulence in humans. Effects of soaking, soaking with ultrasound (47 MHz), soaking with high hydrostatic pressure (HHP, 621 MPa), and subsequent cooking on the oligosaccharide content of lentils, chickpeas, peas, and soybeans were investigated. Legumes were soaked for 3 or 12 hr in water, soaked for 1.5 or 3 hr with ultrasound, or soaked for 0.5 or 1 hr with HHP. Oligosaccharides of lentils and chickpeas were mainly composed of raffinose, ciceritol, and stachyose, while those of peas and soybeans were raffinose and stachyose. Verbascose was the minor oligosaccharide in lentils and peas and was absent in chickpeas and soybeans. Ciceritol was not detected in peas and soybeans. Total oligosaccharide content of raw legumes ranged from 70.7 mg/g in yellow peas to 144.9 mg/g in chickpeas. Soaking was effective for the reduction of oligosaccharides in the tested legumes. Compared with soaking for 3 hr, soaking legumes with ultrasound for 3 hr in all tested legumes or soaking legumes with HHP for 1 hr, with exception of soybeans, appeared to be more effective for the reduction of oligosaccharides. The effect of cooking on the reduction of oligosaccharide content of presoaked legumes was evident in lentils, while oligosaccharide content of chickpeas, peas, and soybeans was either unchanged or even increased by cooking after presoaking, with or without ultrasound, probably due to the leaching of other soluble components and the release of bound oligosaccharides during cooking. During soaking or cooking of legumes, raffinose leached out faster than other oligosaccharides.

Dietary Content and Gastrointestinal Function of Soybean Oligosaccharides in Monogastric Animals

“…A more significant decrease in the levels of raffinose and stachyose was observed in seeds soaked under ultrasound and under high hydrostatic pressure. The lowest content of raffinose (1.03%) and stachyose (1.30%) was noted in cooked seeds soaked under ultrasound for 3 h (Han & Baik, 2006). Cooked seeds soaked under high hydrostatic pressure contained the largest amounts of oligosaccharides.…”

“…Oligosaccharides, next to sucrose, are the most widely distributed water-soluble carbohydrates in the plant kingdom (Han & Baik, 2006). Oligosaccharides (the name is derived from the Greek word oligos, meaning a few) are compounds that yield only monosaccharide units upon complete hydrolysis (Kadlec et al, 2001).…”

“…Depending on the number of monosaccharide residues, oligosaccharides are classified as trisaccharides, tetrasaccharides and so forth. The main group of oligosaccharides present in SBM are the raffinose family oligosaccharides (RFOs), so named after the first member of this homologous series of -galactosides, which are characterized by the presence of (1→6) links between the galactose moieties (Han & Baik, 2006). In addition to raffinose, this group comprises stachyose, verbascose and ajugose, which consist of 1, 2 and 3 (1→6) linked units of galactose bonded through (1→3) to terminal sucrose (Kadlec et al, 2001).…”

Kırmızı ve Yeşil Mercimekten Elde Edilen Diyet Liflerinin Karakterizasyonu ve Fonksiyonel Özellikleri

“…Rafinoz ve stakiyoz baklagillerde yüksek oranlarda görülen oligosakkarit çeşitleridir [7,24]. Mercimeklerin oligosakkarit içeriği pek çok araştırmacı tarafından probiyotik özellikleri ile ilişkilendirildiğinden bu çalışmada tespit edilebilen yüksek rafinoz içeriği mercimek unlarının ve izole edilen çözünür diyet liflerinin sağlık üzerine olumlu etkileri hakkında öngörüde bulunabilmeyi sağlar nitelikte görülmektedir.…”

Dynamics of Some Hydrolytic Enzymes During the Sprouts Production from Lentil Seeds (Lens Culinaris)

“…on the other hand, legumes in particular lentil have been reported to contain adequate amounts of antinutrients such as phytic acid, condensed tannins, protease inhibitors (trypsin and chymotrypsin), α-amylase inhibitors and lectins (3). Moreover, the digestibility of legume protein and legume starch is limited by the presence of oligosaccharides such as raffinose, stachyose and verbascose (11,12,15,16,21). they are not metabolized by humans and can cause flatulence, diarrhoea and indigestion (14).…”