


































Food Science and Nutrition Studies 

ISSN 2573-1661 (Print) ISSN 2573-167X (Online) 

Vol. 3, No. 3, 2019 

www.scholink.org/ojs/index.php/fsns 

96 
 

Original Paper 

Sugar Spectra of Syrups Produced from Different Tuber 

Starches via Crude Enzymes and Amyloglucosidase Sources 

Okafor D.C.1*, Agunwah I.M.1, Ezegbe C.C.2, Ekeoma C.L.1 & Onuegbu N.C.1 

1 Department of Food Science and Technology, Federal University of Technology, Owerri, Imo State, 

Nigeria 

2 Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University 

Awka, Anambra State, Nigeria 

* Okafor D.C., Department of Food Science and Technology, Federal University of Technology, Owerri, 

P. M. B. 1526 Owerri, Imo State, Nigeria  

 

Received: November 12, 2018   Accepted: November 24, 2018   Online Published: August 19, 2019 

doi:10.22158/fsns.v3n3p96        URL: http://dx.doi.org/10.22158/fsns.v3n3p96 

 

Abstract 

Syrup production was done via enzyme hydrolysis. Enzymes used were crude enzymes from malted 

sorghum, wheat and millet and exogenous enzyme by name amyloglucosidase (AMG) which hydrolyzed 

Cassava (Manihot esculenta,), water yam (Dioscorea alata) and potato white (Ipomoea batatas L) 

starches. Syrup sugars were determined using high performance liquid chromatography (HPLC) and 

the sugar profile found are fructose; glucose, sucrose, maltose, D-xylose, and D-Raffinose which 

manifested as a result of the interaction between starches and enzymes. The sugar Fructose was in the 

range of 17.34 ± 0.651 g/l to 28.16 ± 0.982 g/l, Glucose sugar was in the range of 6.09 ± 0.165 g/l to 

177.04 ± 1.229 g/l. The highest glucose yield (177.04 ± 1.229 g/l) was observed in Cassava starch 

reaction with the commercial enzyme –AMG. Sucrose content was in the range of 5.78 ± 0.180 g/l to 

21.59 ± 0.536 g/l, Maltose (23.71 ± 0.125 g/l to 48.04 ± 0.125 g/l) was the most predominant sugar in 

all syrups gotten from the starch and crude enzymes interaction. The hydrolysis of starches using 

different enzyme sources yielded sugar spectra of different sugars concentrations with each starch 

source predisposed to the natural activity of the enzyme peculiar to their variety or cell structure. 

D-xylose and D-Raffinose were in the range of 0.004-0.225 g/l which is very small in quantity 

compared to other sugars seen while no D-stachyose was detected.  

Keywords 

Amyloglucosidase, Crude, Enzymes, Hydrolysis, Starches, Sugars 

 



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1. Introduction 

Root and tuber crops are among the most important group of food crops in many tropical African 

countries. In Nigeria for instance, cassava (Manihot esculenta) is the most important of these crops in 

terms of total production, importance and economic value (Okoye et al., 2008). Cocoyam (Colocasia 

esculenta), which belongs to the Araceae family, ranks third after cassava and yam (Onyenweaku & 

Okoye, 2007). According to a report by Ogunniyi (2008), Nigeria is the world’s largest producer of 

cocoyam, accounting for about 40% of total world output as recorded by the food and agriculture 

organization in 2007 (FAO, 2007). Despite this, Nigeria and other developing nations are beset by the 

problem of lack of proper storage facilities for these tubers and as such, a large number of these tubers 

in the order of millions of tons are destroyed through pest infestation, deterioration, physical damage to 

the tubers, pilfering etc. (Omemu et al., 2005). In order to recover the losses resulting from these 

wastages, it is important to expand the processing range of these tubers with particular focus on 

converting them into value-added products. One of the processing methods that can reduce wastage of 

these tubers is converting them into syrups for multipurpose usages and applications in food and 

beverage industries, as well as in the pharmaceutical industries. Again, with the demand on cane sugar 

as a result of increasing need by the teeming population and industries who seek to satisfy nutritional 

and commercial requirements, there is deficient supply of cane sugar as the quantity produced in the 

country cannot meet up with the increasing demand. Hence the need to source for alternative sources of 

sugar and this is what syrup production provides. 

However, over the years, commercially produced enzymes have been used for syrup production which 

not only is expensive and not readily accessed or available in Nigeria and other tropical countries but 

also very difficult to preserve because they are heat labile. Hence this paper is geared towards 

producing syrup using an alternative source of enzyme other than the exogenous source. The main 

objectives of this paper is to produce sugar syrups by enzyme hydrolysis with exogenous and 

endogenous enzymes [amyloglucosidase (AMG) and crude enzymes from millet, sorghum and wheat 

respectively] and to determine the sugar spectra present in the syrups produced using high performance 

liquid chromatography (HPLC). The quality and state of this paper is new, different and interesting in 

that it will help us to ascertain the ability of tropical malted grains such as wheat, millet, and sorghum 

in hydrolyzing the starches extracted from tropical tubers and roots (cassava, water yam, and potato) 

and the extent of their hydrolysis as when compared to the action of the exogenous enzyme 

(Amyloglucosidase) hydrolysis on these starches. It will advance the knowledge of crude enzymes in 

the field of Food Science and Technology. 

 

2. Materials and Methods 

2.1 Raw Material Collection 

The cassava (Manihot exculenta) tuber known as TME 419, yam (Dioscorea alata ) tuber commonly 

known as water yam, and potato white (Ipomoea batatas L), white colored sorghum (Sorghum vulgare) 



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with varietal name fara-fara, millet (Pennisetum glaneum) known as Ex - Borno and wheat (Triticum 

eastivum) Ex - Jos used were gotten from the Department of Crop Science Michael Okpara University of 

Agriculture Umudike, Abia State, Nigeria. The equipment and some chemicals used for this research 

were all of analytical standards gotten from the department of food science and technology, Federal 

University of Technology Owerri, Imo state and the International Institute of Tropical Agriculture (IITA) 

Ibadan, Oyo state, Nigeria. The exogenous enzyme amyloglucosidase used was gotten from Novo 

Nordisk of Denmark. The solvents used for HPLC analysis are HPLC grade and are gotten from E-Merck 

(Darmstadt, Germany). Other chemicals are also of analytical grade and are gotten from Sigma Aldrich 

(Steinheim, Germany). 

2.2 Preparation of Starch  

The method described by Ige and Akintunde (1981) was used. Starch extraction was carried out from 

the fresh cassava tubers. The tubers were washed, peeled and milled into slurry. The slurry was 

properly stirred and allowed to settle for about 6 hours. After settling of the cassava slurry, a 

heterogeneous mixture was observed, the top part o of the mixture was a transparent liquid and the 

bottom part was a white thick liquid which is starch. The supernatant was decanted and the sediment 

which contains the starch was filtered with muslin cloth and oven-dried at 45-55ºC for 30 minutes to 

produce the dry starch, which was later milled to produce a fine powder. This procedure was followed 

in preparing starch from potato roots and water yam tubers 

2.3 Production of Crude Enzymes 

By malting the grains [Fara fara (sorghum vulgare, a variety of guinea corn) Ex -Borno (Pennisetum 

glaneum a variety of millet) and Ex -jos (Triticum eastivum a variety of wheat)], enzymes were 

developed in them. These enzymes are crude enzymes. The malting was prepared according to the 

method described by Subramanian et al. (1992). The grains were carefully sorted to separate dirt, stones 

and other contaminants. The cleaned grains were soaked in water at a grain to water ratio of 1:3 The 

grains were washed and soaked/steeped separately in portable water for 24 hours and the water were 

changed every 6 hours interval to undergo air rest of 10 mins. They were spread on a jute bag in a room 

for the commencement and completion of sprouting at an ambient temperature (35ºC). 250 ml of water 

for every 500 g of grain was sprinkled every 6hours interval on the grains to enhance sprouting (Figure 1). 

It was germinated for 24 hours before the emergence of grain rootlets after which they were dried in an 

oven at 45ºC to stop the germination. Dry milling was done using a machine and was sieved to a 

fineness of flour using a 5.3 um aperture size sieve to get the malted cereal which contains the crude 

enzymes developed during malting of the grains. 

 



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Figure 1. Flow Diagram for Production of Malted Grains (Wheat, Millet and Sorghum) 

 

2.4 Procedure for Syrup Production Using Exogenous Enzyme Application (Amyloglucosidase) 

The method described by Osuji and Anih (2011) and Okafor et al. (2018) was used. The mash water to 

be used for the syrup production was prepared to a pH of 11 with aid of calcium hydroxide. 20 grams 

of the starch samples were weighed respectively into clean pots. Slurry was made by adding 250 ml of 

the mash water respectively into the weighed starches. The temperature of the slurries was raised to 

45ºC, after which 20 grams of the amylogucosidase enzyme was added to each of the slurries, the 

slurries were stirred and maintained at that temperature for 20 minutes. Temperature was raised to 55ºC, 

they were stirred and allowed to rest for 10 minutes. Iodine tests were carried out by adding 2 drops of 

iodine to a few drops of the samples on a ceramic tile. The temperature of the slurries was raised to 65ºC 

and maintained for 1 hour. Another iodine tests were carried out. Temperatures were further raised to 

90-93ºC and maintained for another 1 hour. The slurries were then boiled for 5 minutes, after which 

iodine tests were carried out. The samples were then cooled to 60ºC by placing them in an ice water bath. 

The pH of the samples was checked. After hydrolysis, the liquors were boiled for 10 minutes to denature 

enzymes. The converted slurries were then filtered across a double-layered muslin cloth. The samples 

were then evaporated and concentrated through evaporation using a water bath, and then packaged. 

2.5 Procedure for Syrup Production Using Crude Enzyme Application from Malted Cereals 

The method described by Okafor et al (2018 and 2019) was used. The mash water to be used for the 

syrup production was prepared to a pH of 11 with aid of calcium hydroxide. 20 grams of the starch 

samples were weighed respectively into clean pots. Slurry was made by adding 250ml of the mash 



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water respectively into the starches. The temperature of the slurries was raised to 45ºC, after which 3 

grams of the malted grains respectively was added to each of the slurries, the slurries were stirred and 

maintained at that temperature for 20 minutes. Temperature was raised to 55oC, they were stirred and 

allowed to rest for 10 minutes. Iodine tests were carried out by adding 2 drops of iodine to a few drops of 

the samples on a ceramic tile. The temperature of the slurry was raised to 65ºC and maintained for 1 hour. 

Another set of iodine test were carried out. Temperatures were further raised to 90-93ºC and maintained 

for another 1 hour. The slurries were then boiled for 5 minutes, after which iodine tests were carried out. 

The samples were then cooled to 60ºC by placing them in an ice water bath. The pH of the samples was 

checked, after hydrolysis, the liquors were boiled for 10 minutes to denature enzymes. The converted 

slurries were then filtered across a double-layered muslin cloth. The samples were then evaporated and 

concentrated through evaporation using a water bath, and then packaged. This same procedure was 

repeated for 6, 9, 12, 15 and 20 grams of the malted cereals respectively on each of the three starches.  

2.6 Determination of Brix Level  

The apparent Brix was determined using a portable digital handheld refractometer (VBR32T 

Bellingham and Stanley UK Brix/ATC 0-32%). The digital refractometer was cleaned with a clean 

wiper and standardized with distilled water at 20ºC until the brix value reads zero. Two drops of syrup 

sample at 20ºC was dropped on the lens (sensitive surface) of the refractometer and measured. The 

syrups with the highest brix level were chosen for the sugar spectra analysis using high performance 

liquid chromatography.  

2.7 Determination of Sugar Spectra with High Perfomance Liquid Chromatography Using Refractive 

Index Detector (Hplc-Ri) 

Determination and quantification of specific sugars was performed according to method of Zielinski et 

al. (2014) using HPLC with Refractive Index detector (Waters e2695, USA; 2414 RI Detector) with 

Sugar Analysis 300 x4.6mm column. The analysis was performed at 35ºC with a flow rate of 1 ml 

min-1using isocratic elution with 75% acetonitrile (AcN): 25% water (H2O) mixture as a mobile phase. 

All samples were centrifuged at 4,000 rpm for 10 min (Hermle Labnet Z323) and the supernatant was 

filtered through a 0.22 μm PES membrane (Sartorius Stedim Biotech, Germany). Then the filtrate was 

diluted 10 times before direct injection into the HPLC. The sugars seen and detected were recorded.  

2.8 Statistical Analysis 

Data were expressed as mean ± standard deviation (SD) from two parallel measurements. The analysis 

of variance (ANOVA) and least significant difference (LSD) were performed with the SPSS 20.0 

software (SPSS Inc.) significance difference was defined at Ɵ = 0.05.  

 

3. Results and Discussion 

3.1 Brix Reading of Syrups Produced with Crude Enzymes  

Increase in the brix level of the syrups confirms that there was an interaction between the starches and 

enzymes. From the refractometer readings at different concentration for each of the crude enzyme used, 



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it was observed that the potato white starch with millet crude enzyme at all concentrations gave the 

highest brix level (Table 1). All other starch sources (cassava and water yam starches) on the millet 

crude enzyme gave their highest degree brix at 15 grams concentration. When sorghum crude enzyme 

was used in the hydrolysis, cassava starch was the only starch that gave a reading of 3.0 0BX at 0gram 

concentration of the crude enzyme as against all starch sources that gave zero reading at the 0gram 

concentration of the sorghum crude enzyme. Cassava had degree brix level of 3.0 without any enzyme 

treatment this can be attributed to the variety used and other substances in the multi component matrix 

in which the starch occurs naturally as the gelatinized starch has lost its crystallinity thereby 

accelerating its hydrolysis. Also, since this variety TME 419 gives higher tonnage yield and higher 

starch content as opposed to other cassava varieties which are lower in starch content, it is possible that 

some hydrolysis took place by inherent enzyme in the peel as starch extraction processes took place 

(Tester et al., 2004). Cassava, water yam and potato white starches gave their highest brix level of 16.0, 

13.5 and 15.0 respectively at the 15 grams concentration of the sorghum crude enzyme treatments 

(Table 1). For wheat enzyme treatments, potato white starch set the pace at all concentrations of the 

crude enzyme giving its highest degree brix level at 15 grams concentration of the crude enzyme. All 

starch sources when treated with different crude enzymes gave their best/highest degree brix readings 

at 15 grams concentration of the crude enzyme (Table 1). As a result of the high brix level at this 

concentration, only syrups produced at the 15 gram concentration of the crude enzyme was subjected to 

sugar spectra analysis using HPLC.  

 

Table 1. Brix Reading of Syrups Produced with Crude Enzyme Application at Different 

Concentrations for Different Starch Sources 

Sources of Enzymes Sources of carbohydrates Quantity of crude enzymes applied (Grams) 

  0.0 3.0 6.0 9.0 12.0 15.0 20.0 

Millet Cassava starch 0.0 7.0 9.0 12.0 13.6 15.40 15.30 

 Water yam starch 0.0 9.5 11.3 12.5 13.5 15.0 14.8 

 Potato white starch 0.0 10.5 11.8 13.8 15.5 18.5 18.0 

Sorghum Cassava starch 3.0 9.5 11.9 13.5 14.5 16.0 15.8 

 Water yam starch 0.0 7.4 8.1 10.5 11.7 13.5 13.10 

 Potato white starch 0.0 8.5 9.8 11.5 13.7 15.0 14.8 

Wheat Cassava starch 0.0 6.3 8.5 10.7 12.6 14.7 14.0 

 Water yam starch 0.0 8.5 9.8 10.6 11.3 12.8 12.4 

 Potato white starch 0.0 11.3 12.6 15.0 19.0 25.0 24.8 

 

3.2 Sugar Spectra of Syrups as a Result of Effect of Only Starch Source Interaction 

For fructose, interaction between the starches showed that, water yam starch gave the highest mean 

yield of fructose (11.95 g/l) followed by cassava starch (7.55 g/l) while potato white starch gave the 



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least fructose yield (5.78 g/l) irrespective of the enzymes used. For glucose, cassava starch gave the 

highest mean yield of glucose (48.47 g/l) followed by potato white starch (9.69 g/l) with water yam 

starch giving the lowest yield (3.80 g/l). For sucrose, potato white starch gave the highest mean yield of 

sucrose (11.01 g/l), followed by water yam starch (6.41 g/l) with cassava starch given the least yield for 

sucrose (3.16 g/l). For maltose, potato white starch gave the highest mean yield of maltose (26.09 g/l), 

followed by water yam starch (20.05 g/l) with cassava starch given the least yield for maltose (17.14 

g/l). For D-xylose, potato white starch gave the highest mean yield (0.0082 g/l), followed by water yam 

starch (0.0079 g/l) with cassava starch given the least mean yield for D-xylose (0.0047 g/l). For 

D-Raffinose, potato white starch gave the highest mean yield (0.1218 g/l), followed by cassava starch 

(0.0400 g/l), with water yam starch given the lowest mean yield for D-Raffinose (0.0198 g/l) shown in 

Table 2. Different sugars at variable concentrations indicated interaction that took place as a result of 

the inherent properties (genetic makeup) of the different starch sources  

 

Table 2. Effect of Starch Source Interaction on Sugar Spectra in Grams per Liter (g/l) 

Starch source Fructose Glucose Sucrose Maltose D-xylose D-Raffinose D-stachyose 

CS 7.5514 48.4675 3.1639 17.1416 0.0047 0.0400 0.0000 

WYS 11.9484 3.8013 6.4148 20.0471 0.0079 0.0198 0.0000 

PWS 5.7823 9.6994 11.0100 26.0931 0.0082 0.1218 0.0000 

Means with different alphabet superscript along columns are significantly different (p≥0.05) 

KEY: CS = cassava starch, WYS = water yam starch, PWS = potato white starch 

 

3.3 Sugar Spectra from Enzyme Interaction Only 

When the enzymes interaction only is considered without paying attention to the starch source, millet 

enzyme gave the highest total yield of fructose with mean yield of 14.76 g/l, followed by sorghum 

enzyme (8.76 g/l), wheat (5.14 g/l) and AMG enzyme with the lowest mean yield of 5.05 g/l. AMG 

enzyme gave the highest total yield of glucose (59.65 g/l) followed by millet enzyme (10.03 g/l), wheat 

(6.68 g/l) with sorghum enzyme with the lowest mean yield of 6.27 g/l. The wheat enzyme gave the 

highest total yield of sucrose (9.24 g/l), followed by millet enzyme (9.20 g/l), AMG (5.96 g/l) with 

sorghum enzyme giving the least yield (3.05 g/l). The wheat enzyme gave the highest total yield of 

maltose (28.53 g/l), followed by millet enzyme (20.37 g/l), sorghum (18.37 g/l) and AMG enzyme gave 

the lowest mean yield of 17.10 g/l. The AMG enzyme gave the highest total yield of D-xylose (0.0093 

g/l), followed by wheat enzyme (0.0073 g/l), sorghum (0.0063 g/l) with millet enzyme being the lowest 

(0.0047 g/l). The millet enzyme gave the highest total mean yield of D-Raffinose (0.0830 g/l), followed 

by wheat enzyme (0.0830 g/l), AMG (0.0463) while sorghum enzyme gave the lowest mean yield of 

0.0273 g/l (Table 3). The ability of this enzyme sources to liberate this sugar can be attributed to their 

diastatic power resulting from the amount of diastatic enzymes present in the malted grains which 

varies between the grains (John et al., 1998). 



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Table 3. Effect of Only Enzyme Interaction on the Sugar Spectra in Grams per Liter (g/l) 

Enzyme source Fructose Glucose Sucrose Maltose D-xylose D-Raffinose D-stachyose 

AMG 5.0552 59.6484 5.9563 17.1053 0.0093 0.0463 0.000 

Millet 14.7637 10.0264 9.2048 20.3677 0.0047 0.0853 0.000 

Sorghum 8.7552 6.2730 3.0491 18.3693 0.0063 0.0273 0.000 

Wheat 5.1354 6.6763 9.2414 28.5333 0.0073 0.0830 0.000 

KEY: AMG = Amyloglucosidase 

 

3.4 Sugar Spectra as Shown by the Interaction of both Enzyme and Starch Sources 

When the interaction of both enzyme and starch sources are considered together, the sugars spectra are 

affected. Water yam starch and millet gave the highest mean yield of fructose (28.16 g/l), followed by 

the interactive effect of cassava starch and sorghum with mean yield of 17.34 g/l while potato white 

starch and wheat gave the lowest yield (10.49 g/l). The interactive effect between cassava starch and 

AMG enzyme gave the highest mean yield of glucose (177.04 g/l), followed by that of potato white 

starch and wheat enzyme with mean yield of (17.11 g/l), with water yam starch and millet giving the 

lowest glucose yield of 6.09 g/l. The interactive effect between potato white starch and wheat gave the 

highest yield of sucrose (21.59 g/l), followed by the interaction of water yam starch and AMG enzyme 

with yield of 13.9 g/l whereas cassava starch and wheat gave the lowest yield of 4.12 g/l. The 

interaction between potato white starch and wheat enzyme gave the highest yield of maltose (48.04 g/l), 

followed by the interaction effect between water yam starch and sorghum enzyme yielding (32.30 g/l), 

with cassava starch and AMG enzyme giving the lowest maltose yield (24.56 g/l). The interactive effect 

between potato white starch and AMG enzyme gave the highest yield of D-xylose (0.018 g/l), followed 

by the interaction of water yam starch and wheat enzyme yielding (0.0127 g/l), with cassava starch on 

all enzyme sources giving the lowest yield of 0.0047 g/l. The interaction effect between cassava starch 

and AMG enzyme gave the highest mean of D-Raffinose yield (0.0920 g/l), followed by the interaction 

effect between water yam starch and sorghum enzyme with mean yield (0.0390 g/l), while potato white 

starch and wheat enzyme gave the lowest yield of 0.2250 g/l.  

For fructose yield, there is no significant difference between cassava starch on wheat and water yam 

starch on AMG enzyme as, likewise no significant difference exists between water yam starch on wheat 

and potato white starch on sorghum. Other starch sources and enzymes are significantly different with 

respect to yield of fructose sugar.  

For glucose yield, cassava starch on millet and water yam starch on wheat are not significantly different, 

also potato white starch on millet and sorghum are not significantly different but all other starch source 

on all other enzymes are significantly different with regards to the glucose yield. For sucrose yield, 

water yam starch on millet, sorghum and wheat enzyme are not significantly different. All other 

starches on all other enzyme sources are significantly different. 



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For maltose yield, all starch sources on all enzyme sources are not significantly different. 

For D-xylose yield, cassava starch on AMG, millet, sorghum, and wheat enzymes are not significantly 

different, alongside water yam starch on AMG enzymes, and potato white starch on millet, sorghum 

and wheat while water yam starch on millet, sorghum, wheat and potato white starch on AMG are 

significantly different from all other starches on all other enzymes sources but are not significantly 

different in their yield of D-xylose. 

For D-Raffinose yield, cassava starch on wheat and water yam starch on AMG are not significantly 

different. Cassava starch on sorghum and potato white starch on millet, sorghum and wheat are not 

significantly different. Cassava starch on millet and potato white starch on AMG are not significantly 

different. Potato white starch on millet and sorghum are not significantly different, but cassava starch 

on AMG and potato white starch on wheat are significantly different from among all the starch sources 

and enzymes as shown in Table 4. The discussions agree with the results of the study conducted by 

other researchers. In fact, Osuji and Okafor (2013), Okafor et al. (2019) have worked on Soymilk and 

revealed the existence of significant differences among the sugar content of soymilk after different 

enzyme treatment using HPLC. Among the sugars identified include glucose, fructose, maltose, 

Raffinose, Xylose and stachyose. The presence of stachyose as identified in their work can be attributed 

to the action of the cell wall degrading enzyme used as opposed to this research where stachyose was 

not identified because the hydrolysis was mainly as a result of Oligosaccharide degrading enzymes.  

 

Table 4. The Sugar Spectra of the Interactive Effect of Enzymes and Starches (g/l) 

Starch Enzyme Fructose Glucose Sucrose Maltose D-xylose D-Raffinose D-Stachyose 

CS AMG 0.1270d ± 0.010 177.0383a ±1.229 3.1607h ± 0.055 24.5643h ± 0.125 0.0047b ± 0.006 0.0920d ± 0.004 0.000 

 Millet 11.1170f ± 1.210 6.9790h ± 0.069 1.3996g ± 0.005 13.5533k ± 0.125 0.0047b ± 0.006 0.0160b ± 0.004 0.000 

 Sorghum 17.3413b ± 0.651 8.9627e ± 0.061 3.9877j ± 0.044 16.5993l ± 0.125 0.0047b ± 0.006 0.0390e ± 0.004 0.000 

 Wheat 1.6203c ± 0.451 0.8900i ± 0.014 4.1077e ± 0.105 13.8493i ± 0.125 0.0047b ± 0.006 0.0130f ± 0.004 0.000 

WYS AMG 14.8217c ± 0.563 1.0910f ± 0.020 13.9087f ± 0.128 23.5833f ± 0.125 0.0047b ± 0.006 0.0140f ± 0.004 0.000 

 Millet 28.1590a ± 0.982 6.0930j ± 0.165 5.7837h ± 0.180 0.5873d ± 0.125 0.0047a ± 0.006 0.0150e ± 0.004 0.000 

 Sorghum 1.5130j ± 0.265 5.9940g ± 0.025 3.9430h ± 0.128 32.3033j ± 0.125 0.0097a ± 0.006 0.0390e ± 0.004 0.000 

 Wheat 3.3000h ± 0.159 2.0270h ± 0.097 2.0237i ± 0.103 23.7143g ± 0.125 0.0127a ± 0.006 0.0110e ± 0.004 0.000 

PWS AMG 0.2170g  ± 0.003 0.8160c ± 0.075 0.7998b ± 0.004 3.1683a ± 0.125 0.0187a ± 0.006 0.0330b ± 0.004 0.000 

 Millet 5.0150i ± 0.265 17.1120d±0.389 20.431c ± 0.527 46.9623c ± 0.125 0.0047b±0.006 0.2250a±0.004 0.000 

 Sorghum 7.4113h ± 0.751 3.8623d ± 0.064 1.2167a ± 0.093 6.2053b ± 0.125 0.0047b ± 0.006 0.0040a ±0.0040 0.000 

 Wheat 10.4860d ± 0.854 17.1120b ± 0.389 21.5930d ± 0.536 48.0363e ± 0.125 0.0047b ± 0.006 0.2250c ± 0.004 0.000 

LSD  1.098 0.654 0.405 0.218 0.011 0.006 0.000 

KEY: CS = cassava starch, WYS = water yam starch, PWS = potato white starch, AMG = 

Amyloglucosidase. 



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4. Conclusion 

It is evident that enzyme hydrolysis by means of endogenous enzyme can hydrolyze starches to 

produce syrups. Sources of the starches hydrolyzed determines to a great extent the type of sugars to be 

produced in a hydrolysis, as the constituents enzymes developed in a particular malted grain and the 

cell structure of the starch source must be compatible to the intended end product (sugar) in that 

particular hydrolysis. The diastatic power of the grains developed during malting led to more 

production of maltose sugar by the crude enzymes. Food and beverage industries, institutions and, 

private investors should harness the opportunity of producing syrups from crude enzymes and choices 

as to what type of sugar they want to dominate the syrups affect their starch source and enzyme source. 

This can be achieved by choosing among the starches and enzymes that produce the best result for any 

particular sugar of interest. For a syrup rich in fructose water yam starch is the ideal starch and malted 

millet as source of enzyme, for a sucrose rich syrup, potato white starch is the ideal starch and malted 

wheat as the source of enzyme etc. This paper has established the fact that a particular sugar type can 

dominate all other sugars in syrup. This paper has provided alternatives on how a particular sugar can 

be obtained in syrup at different preferred or desired concentrations to meet consumer’s preferences 

using crude enzymes. 

 

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