Effect of Germination and Fermentation on Carbohydrate Composition of Australian Sweet Lupin and Soybean Seeds and Flours

Abstract

This study investigated the effect of germination and fermentation on the composition of carbohydrates in Australian sweet lupin. Specifically, the amount of sugars (sucrose, fructose, and glucose), starch, oligosaccharides (verbascose, stachyose, and raffinose), and dietary fiber were measured in germinated lupin seeds and fermented lupin flour, and compared with those in soy. High performance liquid chromatography coupled with refractive index was employed for quantitation of sugars, starch, and oligosaccharides, and gas chromatography coupled with a flame ionization detector was used for quantitation of simple sugars in total, and soluble, and insoluble dietary fiber. The enzyme activities of α-amylase and α-glucosidase were compared before and after germination or fermentation. The α-amylase activity in germinated lupin increased to ∼17 nmol/mL/min/0.1 g and in germinated soy∼32; in fermented lupin, the activity increased to ∼52, while in fermented soy it decreased to ∼20. In general, germination or fermentation decreased the oligosaccharide content, and increased the total sugar in samples (p < 0.05). Total oligosaccharides in lupin after uncontrolled germination were reduced by 98% to 6 mg/g, and after controlled germination reduced by 44% to 86 mg/g. Fermentation with yogurt culture lowered the content of total oligosaccharides due to 94% decrease in stachyose. Total oligosaccharides in soy flour prior to fermentation were 180 mg/g and significantly decreased to ∼124 mg/g in fermented soy. Germination did not affect the starch content. There was no significant change in the amounts of total, soluble, and insoluble dietary fiber after germination or fermentation of lupin except for galactose, which was significantly reduced in germinated lupin seeds. Soluble dietary fiber in germinated soy significantly increased. Germination and fermentation are simple and effective techniques to reduce the oligosaccharides while maintaining the composition of dietary fibers.

Physicochemical, Microbiological and Functional Properties of Camelina Meal Fermented in Solid-State Using Food Grade Aspergillus Fungi

“…The starch content of 0.18% in UCAM increased (p < 0.05) to 1.13% in ASCAM, 0.94% in AFCAM and 1.03% in COCAM. This result is in line with an earlier finding [47] which reported an increase in the starch content of soy flours after fermentation. However, fermented flours are typically known to have lower starch and higher sugar contents [37,48], thus, more studies are needed to investigate the variations in results.…”

Improvement of soybean cultivars for natto production through the selection of seed morphological and physiological characteristics and seed compositions: A review

“…A reduction on total oligosaccharides from 180 to ~124 mg/g in fermented soybean flour was observed by Kaczmarska et al (). Fermentation reduced mainly the glucose level, which could be used as a carbon source by microorganisms (Kaczmarska et al, ). Fermentation with B. subtilis natto can remove anti‐nutritional factors such as protease inhibitors (trypsin inhibitors), which inactivate digestive proteases (Gillman, Kim, & Krishnan, ; Zhang et al, ); and soybean protein subunits (Glycinin and β‐conglycinin) that are well known as potential food allergens (Weng & Chen ).…”

“…After fermentation, there are not significant changes in the fat and fiber contents of soybean. However, the carbohydrates almost disappear (Kaczmarska, Chandra‐Hioe, Zabaras, Frank, & Arcot, ; Kanno & Takamatsu, ). A reduction on total oligosaccharides from 180 to ~124 mg/g in fermented soybean flour was observed by Kaczmarska et al ().…”

“…However, the carbohydrates almost disappear (Kaczmarska, Chandra‐Hioe, Zabaras, Frank, & Arcot, ; Kanno & Takamatsu, ). A reduction on total oligosaccharides from 180 to ~124 mg/g in fermented soybean flour was observed by Kaczmarska et al (). Fermentation reduced mainly the glucose level, which could be used as a carbon source by microorganisms (Kaczmarska et al, ).…”

The Growth of Different Probiotic Microorganisms in Soymilk from Different Soybean Varieties and their Effects on Anti-oxidant Activity and Oligosaccharide Content

“…Cheng, Thompson, & Brittin, 1990;Peng & Guo, 2015;Wang, Kraidej, & Hesseltine, 1974). Fermentation also lowers the content of the oligosaccharides, namely verbascose, stachyose and raffinose, which cause flatulence (Battistini et al, 2018;Gote, Umalkar, Khan, & Khire, 2004;Kaczmarska, Chandra-Hioe, Zabaras, Frank, & Arcot, 2017). Fermented soymilk is easily digestible and has antioxidant properties that prevent cancer (Jooyandeh, 2011;Takagi, Kano, & Kaga, 2015;Telang, Joshi, Sutar, & Thorat, 2010;Vij et al, 2011;Ziaei & Halaby, 2017).…”