By Ibrahim Abd- Elghaney Mohamed B. Sc. Science, Tanta University (1996). High Diploma (Sugar Technology Research Institute, Assuit University, 2002). Master of Science in Sugar Technology Sugar Technology Research Institute (STRI), Assuit University (2012).
Supervised by Prof. Dr. Aref A.M.Aly Prof. of Inorganic Chemistry, Faculty of Science, Assuit University, Prof. Dr., Samir Y. El-Sanat Prof. of Food Science and Technology, Faculty of Agriculture, Kafr -El sheikh University Chem. Mohamed M. El-Tabak Vice president of Delta sugar factories 2012
“Sugar is made in the field, not in the factory” So, the quality of beet plays an important role in the sugar manufacture. Sugar technologists often use an old statement regarding a sugar factory’s goal: “The sugar factory does not make sugar, it separates nonsugars”
Melassigenic coefficient of nonsugars NaOHCaCO 3 NaClKClBetaineKNaCaMg Invert sugar 4.612.882.582.481.031.000.950.660.610.19 At least 4.61 kg of sugar is lost to molasses for each kg of NaOH. Generally,,,,,,,,,,,,, Each kg (ton or pound) of non sugars carries about 1.5 kg (ton or pound ) of sugar into molasses.
Increase sugar yield (i.e. increasing juice purity by one unit results in an increases of sugar yield by approximately 1.5%). Decrease molasses yield and sugar loss to molasses (i.e. increasing juice purity by one unit results in a decrease of sugar losses in molasses by about 0.2% OB).
The amount of NSE depends on beet quality. With processing healthy beet, an efficiency of 20 to 30% is usually expected, but processing damaged beet may result in a nonsugar elimination of 10 to 15%.
A - Removable nonsugars (RNS): 1 – Non sugars (NS) that react with lime to produce a precipitate oxalates, phosphates, and sulfates. Na 2 C 2 O 4 + Ca (OH) 2 → CaC 2 O 4 ↓+ 2NaOH K 2 C 2 O 4 +Ca (OH) 2 → CaC 2 O 4 ↓+ 2KOH Then the sodium and potassium hydroxides react with CO 2 during carbonation to form alkaline carbonates, which increase the solubility of the CO 2 in the second carbonation: 2NaOH +CO 2 →Na 2 CO 3 +H 2 O 2KOH +CO 2 →K 2 CO 3 +H 2 O
2 - NS that do not react with lime but are destabilized (Colloids like: pectin, protein).
Nonsugar elimination (NSE) of the evaporation station
3 - NS that do not react with lime but are decomposed as invert sugar, ammonium salts, and glutamine (one type of amino acids).
B - Non removable nonsugars (NRNS): 4- NS that do not react with lime under any circumstances (NRNS) e.g Raffinose, betaine, and amino acids. Raffinose Betaine
Nitrogen fertilization of sugar beet should be managed to produce high root tonnage with high sucrose concentration and purity levels with minimal top growth. The economic yield of sugar beet, thus closely relates to the sugar accumulation process. On the other hand, root quality as TSS, sucrose and juice purity were significantly decreased by increasing nitrogen rates. Excess nitrogen in the soil can both reduce sucrose content and increase nitrate impurities that lower sucrose recovery. Agronomic factors (Nitrogenous fertilizers)
Response of sugar beet to increasing nitrogen fertilizer amounts. Example for a120 kg N /ha optimum application.
۩ Beet growers must control the addition of nitrogen fertilizer, where it not only increases most of the major nonsugars, in particular α- amino nitrogen resulting in lower crystalizable sugar and alkalinity, but it also has detrimental effects on sugar content, marc, invert sugar, lime salts, color and raffinose.
۩The higher the nitrogen used, the higher is the raffinose content, where it influences the crystal habit of sucrose and highly molassigenic. ۩In European factories the beet which has 50 mg /100 g beet α-amino nitrogen is rejected.
Introducing the simple new equation for predicting the true sucrose values of sugar beet as a promising tool, to minimize the losses in readement of sugar recovery (%) of the sugar factories was suggested. The effect of both hot and cold liming (% NS) addition on the juice purification efficiency, sugar recovery, and sugar losses to molasses.
In addition, in this work correlations between the uncontrolled addition of nitrogen fertilizer and the beet sugar content, purity of raw juice, alkalinity coefficient, impurity value, and raffinose formation were studied.
European beet rootEgyptian beet rootIndicators 18.11 a 17.65 b Sugar polarity (% ) 3.86 b 6.18 a Potassium ( mmol / 100 g beet) 1.01 b 3.88 a Sodium ( mmol / 100 g beet) 1.85 b 4.22 a α–amino nitrogen (mmol / 100 g beet ) 88.24 a 76.54 b Quality of beet( %) 109.40 b 310 a Reducing sugar (mg /100 g beet) 72.72 b 450 a Raffinose (mg /100 g beet) 92.12 a 84.40 b Raw juice purity (%) 2.65 a 2.40 b Alkalinity coefficient (mmol / 100 g beet) 6.11 b 12.10 a Impurity value (g/100gm sugar) 1.53 b 3.54 a Loss of molasses% on beet 15.98 a 13.51 b Sugar yield (%OB)
Period (10 days) α-Amino nitrogen mmol /100 g beet Apparent Sucrose ( % ) True Sucrose ( %) Raffinose ( %) Reducing sugar ( %) Others # ( %) 14.84 a 15.28 g 14.67 g 0.35 d 0.24 d 0.02 d 24.5 ab 16.87 f 16.16 f 0.41 cd 0.28 bcd 0.02 d 34.18 bcd 17.72 e 16.91 e 0.47 ab 0.34 ab 0.0 f 44.32 bc 18.37 e 17.58 e 0.46 bc 0.33 abc 0.0 f 54.14 bcd 19.29 d 18.5 d 0.44 bc 0.3 bc 0.05 a 64.08 bcd 19.89 cd 19.14 cd 0.44 bc 0.28 cd 0.03 c 74.3 bc 20.89 ab 20.05 ab 0.49 ab 0.33 abc 0.02 d 84.23 bcd 21.07 a 20.31 a 0.45 bc 0.3 bc 0.01 e 94.01 cd 20.36 abc 19.53 bc 0.47 ab 0.32 abc 0.04 b 104.07 bcd 20.41 abc 19.57 bc 0.49 ab 0.33 ab 0.02 d 113.79 d 20.32 bc 19.4 bc 0.52 a 0.37 a 0.03 c Over all mean 4.2219.1318.350.450.310.02
True sucrose ( Y )Apparent sucrose ( X) Identification 3.3083.524 Sample variance -0.307- 0.189 Kurtosis 0.459 Standard Error of Kurtosis -0.812- 0.853 Skewness 0.231 Standard Error of Skewness 18.368819.1475 Mean 109 Count 1.818671.87713 Standard Deviation 18.8819.6400 Median 0.174200.17980 Standard Error of Mean 2002.202087.08 Sum 13.8814.30 Minimum 21.1522.16 Maximum The determination of true sucrose of sugar beet is based on the following simple equation: Y = (AX) + B, where: Y is a true sucrose, A and B are coefficients and X is the apparent sucrose.
A chart illustrating the apparent and true sucrose concentration
Invert sugar Melanoidins are usually produced in the process either by alkaline degradation of monosaccharides or either reaction with amines in the Maillard reaction :
After the juice has been decalcified, 100-150 ppm SO 2 is normally added to deal with the residual amount of monosaccharides.
Period (10 days) Sugar polarity (%) α-amino N (% sugar) Max. α-amino N (% sugar) αN increasing (% sugar) Pol decreasing (%) 114.02 g 0.967 a 0.20.767 a 5.8 a 215.17 f 0.839 b 0.20.639 b 4.8 b 316.31 e 0.716 c 0.20.516 c 3.9 c 417.11 d 0.709 c 0.20.509 c 3.8 c 517.72 c 0.654 cd 0.20.454 cd 3.4 cd 618.17 b 0.628 d 0.20.428 d 3.2 d 719.33 a 0.624 d 0.20.424 d 3.2 d 818.99 a 0.624 d 0.20.424 d 3.2 d 919.05 a 0.586 de 0.20.386 de 2.9 de 1019.09 a 0.597 de 0.20.397 de 3.0 de 1119.25 a 0.551 e 0.20.351 e 2.6 e Over all mean 17.66 (B) 0.681 (A) 0.20.481 (A) 3.6 (A) Mean of 2005- 2010 # 18.30 (A) 0.508 (B) 0.20.308 (B) 2.3 (B)
Dutton and Bowler found that, an increase in amino nitrogen concentration in roots of 100 mg N/100g sugar decreased sugar percentage by about 0.8%. Pol decreasing (%) = 0.80 % × (increasing in α-amino nitrogen % sugar). For optimum returns for grower and processor they suggested that the aim should be to set an upper limit of 150 mgN/100 g sugar for mineral soils and 200 mgN/100 g sugars for organic soils.
Lime % N.S Specification 73%72%71%70%69%67%65% 86.3 Raw juice purity % 2.86 N.S in Raw juice % on Beet 89.3 ab 89.5 a 89.3 ab 89.0 bc 88.8 c 88.7 cd 88.5 d Thin juice purity % on Beet 2.16 cd 2.11 d 2.16 cd 2.22 bcd 2.27 abc 2.29 ab 2.34 a N.S in Thin juice % B 0.70 ab 0.75 a 0.70 ab 0.64 bc 0.59 cd 0.57 de 0.52 e N.S Elimination in juice purification %B 24.48 a 26.22 a 24.48 a 22.38 b 20.63 bc 19.93 cd 18.18 d Juice purification efficiency% 82.8 ab 83.1 a 82.8 ab 82.2 bc 81.9 c 81.7 cd 81.3 d Recovery% 3.0 a 3.2 a 3.0 ab 2.7 bc 2.5 cd 2.4d e 2.2 e Gain in purity 37.2 a 39.7 a 37.2 ab 33.5 bc 31.0 cd 29.8 de 27.3 e Sugar increasing (Ton/ day) 3.02 cd 2.99 d 3.05 cd 3.15 bcd 3.21 abc 3.25 ab 3.31 a Sugar loss to Molasses % on Beet
Lime % N.S Specification 81%80%78%75%71%68%65% 86.3 Raw juice purity % 2.86 N.S in Raw juice % on Beet 89.8 ab 90.2 a 89.9 ab 89.6 bc 89.3 c 88.9 d 88.4 e Thin juice purity % on Beet 2.04 d 1.96 e 2.02 de 2.09 cd 2.16 c 2.25 b 2.36 a N.S in Thin juice % B 0.81 ab 0.90 a 0.84 ab 0.77 bc 0.70 c 0.61 d 0.50 e N.S Elimination in juice purification %B 28.32 b 31.47 a 29.37 ab 26.92 bc 24.48 c 21.33 d 17.48 e Juice purification efficiency% 83.7 ab 84.4 a 83.8 ab 83.3 bc 82.8 c 82.0 d 81.1 e Recovery% 3.5 ab 3.9 a 3.6 ab 3.3 bc 3.0 c 2.6 d 2.1 e Gain in purity 43.4 b 48.3 a 44.6 ab 40.9 bc 37.2 c 32.2 d 26.0 e Sugar increasing (Ton/ day) 2.89 d 2.77 e 2.86 de 2.96 cd 3.05 c 3.18 b 3.34 a Sugar loss to Molasses % on Beet
A chart illustrating the development of thin juice purity with lime % N.S. addition during hot and cold liming.
A chart illustrating the development of the juice purification efficiency with lime % N.S. added during hot and cold liming.
A chart illustrating the decrease in the sugar loss to molasses % on beet with lime % N.S. added during hot and cold liming.
Solubility of Calcium Hydroxide Only dissolved CaO can react with nonsugars. CaO is slightly soluble in water, but its solubility improves in the presence of sucrose (formation of a Calcium saccharate ion) Ca (C 12 H 22 O 11 ) 2. CaO solubility increases further in impure sugar solutions, which favors sugar technological applications.
CCCCold liming is more effective: Because of decreasing temperature increases the solubility of CaO in the juice. That leads to increase the reaction of lime with nonsugars, i.e. (the solubility of CaO in a 14% sucrose solution at 40°C, is 1.5% by mass, but at 80°C, it is about 0.5%).
I.Beet growers must control the addition of nitrogen fertilizer, where it not only increases most of the major nonsugars, in particular α-amino nitrogen resulting in lower crystalizable sugar and alkalinity, but it also has detrimental effects on sugar content, marc, invert sugar, lime salts, color and raffinose.
II.Introducing the simple new equation predicting the true sucrose values of sugar beet as a promising tool to minimize the losses in readement of sugar recovery % of the sugar factories. On the other hand,,,,,, The present investigation could be helpful for setting up accurate parameters for purchasing the sugar beet in sugar factories.
III.The using of cold liming is better than that of hot liming due to: Sugar recovery, gain in purity, removable non sugar (RNS), and consequently N.S.E, is higher than that of hot liming. Meanwhile,, Lime salt content (Hardness), sugar color and sugar losses in molasses are less than that of hot liming.
IV.Reducing sugars, betaine and raffinose should be included in quality assessments more regularly. V.The necessity of manufacturing sugar beets just after harvesting to reduce sugar losses during manufacturing and prevent degradation of sucrose to invert sugar and colored compounds, which decrease the crystallization of sucrose.