The effect of varied processing variables (yam slice thickness, drying temperatures and type of drying) were investigated to determine their effects on the proximate and some functional properties of yam flour. The ...The effect of varied processing variables (yam slice thickness, drying temperatures and type of drying) were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values (6.20%-6.87%) followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.展开更多
Cucumeropsis mannii, an underutilized oil seed was processed into raw full fat and defatted seed flours and its chemical, functional properties and anti-nutritional factors were determined using standard techniques. T...Cucumeropsis mannii, an underutilized oil seed was processed into raw full fat and defatted seed flours and its chemical, functional properties and anti-nutritional factors were determined using standard techniques. The effects of sample concentration and pH on the foaming properties of the seed flours were determined. The results showed that the full fat and defatted seed flours contained the following in g/100 g sample; 5.0 and 5.1; 45.8 and 1.0; 39.4 and 78.7; 3.45 and 4.40; 1.50 and 3.05; 4.85 and 7.75 for moisture, crude fat, protein, ash, crude fibre and carbohydrate, respectively. The most abundant mineral elements in the seed flour (mg/100 g) are potassium (198.5), followed by nickel (30.0) and magnesium (28.4). The water absorption capacity, oil absorption capacity, foaming capacity and stability, least gelation concentration, emulsion capacity and bulk density are 55.5% and 125.0%; 128.8% and 184.0%; 10.5% and 17.0%; 3.0% and 1.5%; 16.0% and 10.0 g/mL; 85.0 and 115.0 mL/g; 0.42 and 0.25 g/mL, respectively. Defatting influenced the functional properties. The foaming capacity is dependent on sample concentration and pH. The protein solubility of the full fat and defatted seed flours was minimum between pH 3 and 4 and maximum at pH 11. The anti-nutritional composition of the seed flour revealed the following: tannic acid, 1.54 mg/100 g; phytin phosphorus, 0.70 rag/g; phytic acid, 2.48 mg/g; oxalate, 1.85 mg/g; alkaloids 1.97% and saponin 0.50%. The seed flours (full fat and defatted) have potential as nutrient supplement, thickeners and emulsifiers in food system.展开更多
GM1 is a common ganglioside pentasaccharide present on mammalian cell surface.It has been shown to play important roles in cellular communications and initiation of β-amyloid aggregation.In order to synthesize GM1,an...GM1 is a common ganglioside pentasaccharide present on mammalian cell surface.It has been shown to play important roles in cellular communications and initiation of β-amyloid aggregation.In order to synthesize GM1,an efficient synthetic route was developed via a [3+2] strategy.The GM3 trisaccharide acceptor bearing an azido propyl group at the reducing end was prepared using the traditional acetamide protected sialyl thioglycosyl donor,which gave better stereoselectivity than sialyl donors protected with trichloroacetamide or oxazolidinone.The glycosylation of the axial 4-hydroxyl group of GM3 by the disaccharide donor was found to be highly dependent on donor protective groups.Donor bearing the more rigid benzylidene group gave low glycosylation yield.Replacing the benzylidene with acetates led to productive coupling and formation of the fully protected GM1 pentasaccharide.Deprotection of the pentasaccharide produced GM1 functionalized with the aminopropyl side chain,which will be a valuable probe for biological studies.展开更多
文摘The effect of varied processing variables (yam slice thickness, drying temperatures and type of drying) were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values (6.20%-6.87%) followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.
文摘Cucumeropsis mannii, an underutilized oil seed was processed into raw full fat and defatted seed flours and its chemical, functional properties and anti-nutritional factors were determined using standard techniques. The effects of sample concentration and pH on the foaming properties of the seed flours were determined. The results showed that the full fat and defatted seed flours contained the following in g/100 g sample; 5.0 and 5.1; 45.8 and 1.0; 39.4 and 78.7; 3.45 and 4.40; 1.50 and 3.05; 4.85 and 7.75 for moisture, crude fat, protein, ash, crude fibre and carbohydrate, respectively. The most abundant mineral elements in the seed flour (mg/100 g) are potassium (198.5), followed by nickel (30.0) and magnesium (28.4). The water absorption capacity, oil absorption capacity, foaming capacity and stability, least gelation concentration, emulsion capacity and bulk density are 55.5% and 125.0%; 128.8% and 184.0%; 10.5% and 17.0%; 3.0% and 1.5%; 16.0% and 10.0 g/mL; 85.0 and 115.0 mL/g; 0.42 and 0.25 g/mL, respectively. Defatting influenced the functional properties. The foaming capacity is dependent on sample concentration and pH. The protein solubility of the full fat and defatted seed flours was minimum between pH 3 and 4 and maximum at pH 11. The anti-nutritional composition of the seed flour revealed the following: tannic acid, 1.54 mg/100 g; phytin phosphorus, 0.70 rag/g; phytic acid, 2.48 mg/g; oxalate, 1.85 mg/g; alkaloids 1.97% and saponin 0.50%. The seed flours (full fat and defatted) have potential as nutrient supplement, thickeners and emulsifiers in food system.
文摘GM1 is a common ganglioside pentasaccharide present on mammalian cell surface.It has been shown to play important roles in cellular communications and initiation of β-amyloid aggregation.In order to synthesize GM1,an efficient synthetic route was developed via a [3+2] strategy.The GM3 trisaccharide acceptor bearing an azido propyl group at the reducing end was prepared using the traditional acetamide protected sialyl thioglycosyl donor,which gave better stereoselectivity than sialyl donors protected with trichloroacetamide or oxazolidinone.The glycosylation of the axial 4-hydroxyl group of GM3 by the disaccharide donor was found to be highly dependent on donor protective groups.Donor bearing the more rigid benzylidene group gave low glycosylation yield.Replacing the benzylidene with acetates led to productive coupling and formation of the fully protected GM1 pentasaccharide.Deprotection of the pentasaccharide produced GM1 functionalized with the aminopropyl side chain,which will be a valuable probe for biological studies.