Juliano et al. - 1993 - Grain Quality Evaluation of World Rices

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(100:2 w/w) using a Labconco or King digestor. Samples were digested for 20 min or until they were completely clear and then cooled. Water was added up to the 20-ml calibration mark (at room temperature) to dissolve the digest. We transferred a portion of thoroughly mixed solution to the 8-ml sample cup of the AutoAnalvzer for the colorimetric analysis. Blanks and standards were run with the samples. The following reagents were used for the colorimetric ammonia assay: Citrate/tartrate. Na tartrate (600 g) and Na citrate (200 g) were dissolved in about 2500 ml distilled H 2 O. NaOH (80 g) was dissolved in 500 ml distilled H 2 O. We combined the two solutions, added distilled H 2 O to make 4 liters, and shook it well. Alkaline phenate. NaOH (553 g) was dissolved in about 2000 ml of distilled H 2 O. Eighty-nine percent pure phenol (1060 ml) was slowly stirred into the solution while it cooled in an ice bath. Distilled water was added to make 4 liters. It was mixed well, and then stored in a refrigerator. Hypochlorite. Commercial "chlorox" bleach (about 5% by weight NaOCl) was used. 10% sulfuric acid. Instead of H 2 O, 10% sulfuric acid was used for blank wash. Concentrated H 2 SO 4 (100 ml) was added to about 700 ml distilled H 2 O in a 1000-ml volumetric flask. It was cooled, made up to volume, and then shaken. Apparent amylose content The modified simplified assay of Juliano et al (1981) was used. Milled rice flour (100 mg) was weighed in duplicate in 100-ml volumetric flasks. We then added 1 ml of 95% ethanol, washing down any sample adhering to the flask, followed by 9 ml of 1 N NaOH. The suspension was heated in a boiling water bath for 10 min to gelatinize the starch and then cooled for 1 h at room temperature. Samples were diluted to volume with distilled H 2 O and mixed well. Portions of the starch solution were transferred into AutoAnalyzer cups. The amylose-iodine blue color was determined at 608 nm at 78 samples/h (Juliano and Pascual l980). A calibration curve was made with each set of unknown samples by plotting the absorbance of check milled samples against their known amylose content. Iodine solution prepared daily consisted of 3 ml 0.2% I 2 in 2% KI and 1 ml 1 N acetic acid diluted to 100 ml. The amylose contents of check milled samples were obtained from 95% ethanol-defatted milled rice flour (reflux 18-24 h) using standard 6 Grain quality evaluation of world rices
mixtures of 70 mg waxy rice flour (amylopectin), 10 mg amylose + 60 mg waxy rice, 20 mg amylose + 50 mg waxy rice, 25 mg amylose + 45 mg waxy rice, and 30 mg amylose + 40 mg waxy rice in 100 ml 0.09 N NaOH. Undefatted check samples could be used for the calibration curve of undefatted milled rice. Results were expressed on a dry weight basis. Reagents: NaOH, 1 N. Forty grams anhydrous NaOH were dissolved in 1 liter of distilled H 2 O. NaOH, 0.09 N. Nine milliliters 1 N NaOH were diluted into 100 ml with distilled H 2 O. Acetic acid, 1 N. Glacial acetic acid (57.75 ml) was dissolved in distilled H 2 O in a 1-liter volumetric flask and made up to volume. Iodine solution 0.2% I 2 in 2% KI. Two grams iodine and 20 g KI were dissolved in distilled water in a 1-liter volumetric flask and made up to volume. In the study, AC was classified as waxy 0-5.0%, very low 5.1-12.0%, low 12.1-20.0%, intermediate 20.1-25.0%, and high >25.0% to allow for nonwaxy contamination of waxy rice. Alkali spreading value The method of Little et al (1958) was used. Six whole-grain, milled rice samples were placed in duplicate square plastic boxes (R.P. Cargille Laboratories, Inc., 4.6 × 4.6 × 1.9 cm) containing 10 ml of 1.7% KOH, arranged so that the grains did not touch each other. The boxes were covered and incubated for 23 h at 30 °C. Grain appearance and disintegration were visually rated after incubation, based on the following numerical scale: Description Score Grain not affected 1 Grain swollen 2 Grain swollen, collar incomplete or narrow 3 Grain swollen, collar complete and wide 4 Grain split or segmented, collar complete and wide 5 Grain dispersed, merging with collar 6 Grain completely dispersed and intermingled 7 Check samples with scores of 2-7 were run with each analysis. A rating of 5.5-7.0 was classified in this study as low final gelatinization temperature (55-69 °C); 3.5-5.4, intermediate (70-74 °C); 2.6-3.4, intermediate-high; and 1.0-2.5, high (74.5-80 °C). Materials and methods 7
Page 2 and 3: Grain Quality Evaluation of World R
Page 4 and 5: Contents Foreword vii Abstract viii
Page 6: Russia 61 Spain 62 Summary 63 Afric
Page 9 and 10: Abstract P hysicochemical data on p
Page 12 and 13: Introduction D ata bases are availa
Page 15: Table 2. Classification of properti
Page 20 and 21: Gel consistency Rice flour prepared
Page 22 and 23: excessive pressure on the load cell
Page 24 and 25: Asia I n 1989, Asia produced 449.3
Page 27 and 28: Most Bangladeshi rice varieties are
Page 29 and 30: Cambodia A nnual rough rice product
Page 31 and 32: Type III, high-AC rice, has low wat
Page 33 and 34: Iran T he rough rice production in
Page 35 and 36: The Korean varieties had low-interm
Page 37 and 38: Serendah Kuning had high AC, with e
Page 39 and 40: all had low AC (except for Khaupher
Page 41 and 42: Philippines T he Philippines produc
Page 43 and 44: elatively low AC (Y.C. Teng, Counci
Page 45 and 46: other market samples had low AC, ex
Page 47 and 48: Summary Medium grains predominate i
Page 49 and 50: Grain length and width were negativ
Page 51: Table 6. Protein content and classi
Page 54 and 55: (Dalrymple 1986). A market sample o
Page 56 and 57: ack ( r = 0.89*) and peak viscosity
Page 58 and 59: IRRI analyses confirmed Webb's phys
Page 60 and 61: BraziI A nnual rough rice productio
Page 62 and 63: long, slender grain and translucenc
Page 64 and 65: Rices from Paraguay had mostly high
Page 66 and 67: Venezuela R ough rice production in
Page 69 and 70:
Europe E urope produced 2.2 million
Page 72 and 73:
France F rance produced 96,000 t of
Page 74 and 75:
no aroma. A market sample of short-
Page 76 and 77:
low GT, and mainly soft GC (Table 7
Page 78:
Summary The japonica type varieties
Page 81:
Table 8. Protein content and classi
Page 84 and 85:
setback ( r = 0.92**, n = 12) and c
Page 86 and 87:
Suakoko 8, well-suited for cultivat
Page 88 and 89:
unpubl. data). Protein content was
Page 90 and 91:
Sierra Leone R ough rice production
Page 92 and 93:
Summary High-AC rices predominate i
Page 94 and 95:
Table 9. Classification of O. glabe
Page 96:
Table 11. Summary of protein conten
Page 99 and 100:
References cited Adewusi A O, Nyant
Page 101 and 102:
Juliano B O (1985) Criteria and tes
Page 103 and 104:
Acknowledgments The data on propert
Page 105 and 106:
France — Laboratoire de Cereales,
Page 107 and 108:
Sources of 1990 grain quality infor
Page 109 and 110:
Cross reference index of variety na
Page 111 and 112:
Acronyms of rice varieties/lines Co
Page 113 and 114:
H H H HSC IAC ICA ICTA IET IGP INIA
Page 115 and 116:
RP RPW RTN RU S SL SLU SML SPR SR T
Page 117:
Appendix Quality characteristics of
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Date Amy- Alkali Gel Amylograph vis
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Date Crop analyzed year (mo) (yr) A
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Crop year Date analyzed (mo) (yr) A
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Juliano et al. - 1993 - Grain Quality Evaluation of World Rices

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