• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.793-796
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• 2015

The in-vitro starch digestibility of white and brown rice flours was continuously characterized from a rheological point of view. Specifically, the in-vitro viscosities of the rice digesta samples were monitored under simulated oral, gastric, and intestinal conditions. A trend of decreasing viscosities in all the digesta samples was observed during the in-vitro digestion. After cooking, the brown rice sample exhibited lower viscosity than that of the white rice flour due to the presence of more non-starch components. A similar tendency was observed during the simulated oral and gastric digestions. However, the viscosity crossover between the white and brown rice samples was observed during intestinal digestion. In addition, the amount of glucose released from the brown rice flour was significantly lower than that from the white rice flour. Thus, the slower rate of starch hydrolysis in the brown rice flour could be related to its in-vitro rheological behaviors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1310-1315
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• 2016

Germinated brown rice (GBR) has received great attention due to its enhanced nutritional value. Brown waxy rice was germinated at $30^{\circ}C$ for 10 h, 20 h, or 30 h with 95% humidity. The color, texture, digestibility, and sensory characteristics of waxy rice cake made by GBR were evaluated. Pasting viscosity of rice flour was substantially reduced, whereas ${\gamma}$-amino butyric acid content increased with an increase in germination time. Lightness of rice cake with GBR was lower than that with brown rice, whereas the redness and yellowness of rice cake were higher after germination. For textural properties, the hardness, gumminess, and chewiness of rice cake with GBR were lower than those with brown rice, and decreased hardness was more prominent with an increase in germination time. The in vitro starch digestibility of rice cake was elevated by germination, showing an increase in rapidly digestible starch content and decrease in resistant starch content. In the sensory evaluation, the overall acceptability of rice cake with brown rice and GBR was greater than that with white rice, whereas it was reduced with an increase in germination time.

• Journal of the Korean Society of Food Culture
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• v.21 no.2
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• pp.171-178
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• 2006

Tarakjuk with different amylose content was made up using roasted rice flours that consisted of the highest enzyme-resistant starch (RS), while differential scanning calorimetry (DSC) was also utilized to measure the gelatinization temperature of these roasted rice flours in order to establish cooking temperature of tarakjuk. The following qualities of tarakjuk with different amylose content were studied: color, viscosity, spreadability, starch fractions involving total starch (TS), rapidly digestible starch (RDS), slowly digestible starch (SDS) and RS, in vitro starch digestibility (IVSD) and sensory properties. During experimentation, it was found that as the amylose content of the rice flour decreased, the L value of tarakjuk decreased, whereas a value increased significantly (p<0.05). Also, while viscosity showed to increase significantly (p<0.05), on the opposite end, the property of spreadability decreased. TS ranged from $15.95{\sim}17.31%$, RDS $9.36{\sim}10.16%$, SDS $5.46{\sim}6.91%$ and RS $0.33{\sim}1.07%$, on a dry basis. Although the amylose content of rice flours decreased, IVSD increased, however showing no significant difference. When testing the sensory properties of tarakjuk, color and viscosity increased, whereas clumpiness decreased. Ilpum tarakjuk showed the highest score for nutty taste and overall acceptance levels. In fact a high correlation was shown between nutty taste and overall acceptance level (p<0.01), which leads one to believe that nutty taste is a prime factor that greatly influences overall acceptance. Furthermore, viscosity was positively correlated with both a and b values, however negatively correlated with L value (p<0.05). Moreover, roasted nutty taste and overall acceptance were positively correlated with a value (p<0.05), respectively. In conclusion, the above results suggest that tarakjuk could be made by choosing the appropriate rice flour based on the nutritional or sensory purpose.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1609-1613
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• 2013

An experiment was conducted to determine the apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) of phosphorus (P) in copra expellers (CE), palm kernel expellers (PKE), and cassava root (CR). Eight barrows (initial BW of 40.0 kg, SD = 4.5) were individually housed in metabolism crates. A replicated $4{\times}3$ incomplete Latin square design was employed involving 4 dietary treatments, 3 periods, and 8 animals. Three experimental diets contained 40% CE, PKE or CR as the only source of P. A P-free diet mainly based on corn starch, sucrose, and gelatin was also prepared to estimate the basal endogenous loss of P. The marker-to-marker method was used for fecal collection. Values for the ATTD of P in the CE and PKE were greater than in the CR (46.0 and 39.7 vs -14.0%; p<0.05). However, the STTD of P did not differ greatly among the test ingredients (56.5, 49.0, and 43.2% in the CE, PKE, and CR, respectively). In conclusion, the ATTD of P values in CE and PKE were greater than that in CR, but the STTD of P did not differ greatly among CE, PKE, and CR.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.356-361
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• 1998

An experiment was performed to determine if buckwheat intake would improve insulin sensitivity in in normal healthy ras and steptozoticin-induced diabetic Sprague-Dauley rats. For four weeks, rats were fed either corn starch as a cotnrol diet or buckwheat as an experimental diet. As a result, the insulin sensitivity and plasma glucose levels in normal rats were not significantly affected by buckwheat fedding. The insulin sensitivity was lower in diabetic rats than in normal rats(p<0.05). Buckwheat tends to decrease the final plasma glucose level and increase insulin sensitivity in diabetic rats, but there was no sifnificant difference. Another five-week experiment was conducted to determine protein digestibility and protein utility in normal healty rats ad streptozotocin-induced diabetic rats on a control diet or buckwheat diet. The diet composition in this experiment was the same as the preceeding experiment. In the cotnrol diet groups, the protein digestibility in diabetic rats was significantly lower than that in normal rats(p<0.05). Buckwheat reduced protein digestibility in both normal and disbetic rats(p<0.05). Interestingly, in buckwheat diet groups, protei digestibility in diabetic rats was similar to that in normal rats. Protein utility was significantly lower indiabetic rats than in normal rats. This phenomenon was observed as early as the first week of the feeding period. However, protein utility was not sifnificanlty altered in both normal and diabetic rats by buckwheat feeding. It follows that decreased protein digestibility and utility in diabetic rts are not further aggravated by buckwheat feeding, suggesting that buckwheat can be a feasible supplement food for the diabetic therapeutic diet.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.391-397
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• 1997

Six medium-framed steers, fitted with ruminal cannulas, were utilized in a $6{\times}6$ Latin square design with a $3{\times}2$ arrangement of treatments to determine the effects of sorghum hybrid and grain supplementation on nutrient digestibilities and passage rates and ruminal metabolism of silage-based diets fed to growing steers. The diets consisted of three wholes-plant silages (a high grain-containing, grain sorghum and middle-season, moderate grain-containing, and late-season, low grain-containing forage sorghums), each fed with or without 25% rolled grain sorghum. No significant interactions occurred between sorghum hybrid and grain supplementation for the digestion or passage rate criteria measured. Ruminal butyrate concentration was the only fermentation characteristic affected by a hybrid ${\times}$ grain supplementation interaction. The grain sorghum silage diets had the highest DM, OM, and ADF digestibilities; the late-season silage diets, the lowest. Digestibility of NDF tended to be highest (p < 0.10) for the grain sorghum silage, whereas starch digestibility was not affected by sorghum hybrid. Ruminal ammonia, acetate, propionate, butyrate, and total VFA concentrations were highest for the grain sorghum silage diets. Grain supplementation increased DM and OM digestibilities, but had no effect on digestibilities of NDF, ADF, and starch. Ruminal pH was decreased, but total VFA concentration and acetate : propionate ratio were not affected by grain supplementation.

• Korean Journal of Poultry Science
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• v.33 no.3
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• pp.239-248
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• 2006

Improvements in understanding the effects of dietary fermentable carbohydrates and their interaction with supplemental feed enzymes and the feed manufacturing process may lead to reductions in volatile organic compound (VOC) emissions from poultry manure. Starch digestibility has been improved by replacing ground wheat or barley with whole wheat or barley, but there was no consistent effect of cereal species or feed form on the pH value of the gizzard contents. Pelleting results in improvements in feed conversion from 0 to 12%. Starch digestibility has been reported to account for up to 35 % of the improvement in available metabolic energy as a result of xylase supplementation. Factors which affect starch utilization and non-starch polysaccharide (NSP) absorption include the presence of anti-nutrient facto. (ANF) in grains, the nature of grain starch, NSP and the digestive capacity of animals. Improvements in feed production technology have been made in enzyme stabilization, allowing some dry enzyme products to be pelleted after conditioning at up to $87.69^{\circ}C$ and liquid enzymes to be stored in the feed mill for up to low months prior to use. The soluble NSP, arabinokylans and beta-glucans are partially degraded into smaller fragments by enzymes. With fragmentation, the water holding capacity is decreased, which leads to a reduction in digesta moisture, wet feces, and dirty eggs from hens fed diets containing viscosity-inducing ingredients.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.15-22
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• 2005

Extrusion with enzyme treatment improved processing characteristics and physiological activity of whole grains, strongly suggesting industrial potential of whole grains for production of cereal-based functional foods containing activated nutraceuticals. Physicochemical properties of whole grains prepared by extrusion were characterized in terms of vitamin, mineral, and resistant starch contents, gelatinization, and digestibility in comparison with those of raw and roasted grains. Extrusion increased grain gelatinization, with degree of gelatinization in extruded barley being seven times higher than that of raw barley. Extrusion improved digestibility of whole grains in comparison with those of raw and roasted grains. Dispersibility of starch was improved through extrusion, while content of resistant starch decreased. Release of ${\beta}-sitosterol$ present in whole grains increased 13-fold when both extrusion and enzyme treatment were used.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.56-65
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• 1992

The complete nucleotide sequence of the Bacillus circulans F-2 RSDA gene, coding for raw starch digesting a-amylase (RSDA), has been determined. The RSDA structure gene consists of an open reading frame of 2508 bp. Six bp upstream of the translational start codon of the RSDA is a typical gram-positive Shine-Dalgarno sequence and the RSDA encodes a preprotein of 836 amino acids with an Mr of 96, 727. The gene was expressed from its own regulatory region in E. coli and two putative consensus promoter sequences were identified upstream of a ribosome binding site and an ATG start codon. Confirmation of the nucleotide sequence was obtained and the signal peptide cleavage site was identified by comparing the predicted amino acid sequence with that derived by N-terminal analysis of the purified RSDA. The deduced N-terminal region of the RSDA conforms to the general pattern for the signal peptides of secreted prokaryotic proteins. The complete amino acid sequence was deduced and homology with other enzymes was compared. The results suggested that the Thr-Ser-rich hinge region and the non-catalytic domain are necessary for efficient adsorption onto raw substrates, and the catalytic domain (60 kDa) is necessary for the hydrolysis of substrates, as suggested in previous studies (8, 9).

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.5
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• pp.580-587
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• 2010

An experiment was conducted to evaluate the effect of dietary water-soluble carbohydrate extract from Renga renga lily (Arthropodium cirratum) and a commercial product, $Frutafit^{{\circledR}}$ (both fructans) on the performance, organ weights, ileal digestibility and gut morphology of male Cobb broiler chickens. There were six treatment groups: a negative control with no supplements, a positive control supplemented with 45 ppm Zn-bacitracin, and four test diets each supplemented with Renga renga lily extract or Frutafit at 5 or 10 g/kg diet. Supplementation with low levels of Renga renga lily extract and Frutafit in the diet did not affect productive parameters, whereas the inclusion of a high level of Frutafit had a negative effect on BWG and FI compared with birds fed the negative control diet. The addition of an antibiotic to the diet significantly improved (p<0.05) the BWG and FCR of broilers. Apparent ileal digestibility of dry matter, starch, protein and fat was not affected (p>0.05) by supplementation with both levels of lily extract and the low level of Frutafit. The apparent ileal digestibility of dry matter, protein and fat was decreased (p<0.05) by the high level of Frutafit. The apparent metabolisable energy (AME) of the diets fed the high level of Frutafit was approximately 0.2 MJ/kg DM lower than that of the negative control group. The addition of Zn-bacitracin increased (p<0.05) the apparent ileal digestibility of fat. The relative weight of the liver was higher (p<0.05) in broilers supplemented with the high level of Frutafit than for negative control birds at 14 and 35 d of age. Feeding Renga renga lily extract or Frutafit had no effect on the gut morphology of birds on d 14 and 35. It can be concluded that dietary inclusion of fructans from the two sources used in this study affected broiler performance differently and in a dose-dependent manner.