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

ack ( r = 0.89*) and peak viscosity ( r = –0.83*), and grain width
( r = 0.91*). Gel consistency and grain width exhibited very strong correlation
( r = 0.96**).
Mexico
M
exico
produced 506,000 t of rough rice in 1989 (FAO 1990b).
Annual consumption of milled rice per capita was 5.3 kg in
1979-81 (FAo 1984),5.3 kg in 1985 (RCMD 1989),
and 4.9 kg in 1986-88 (FAO 1990a). The principal varieties (based on
area planted) in 1983 were 46% Navolato A71, 17.3% Campeche A80,
8.2% IR8 (Milagro Filipino), and 5.8% CICA4 (Dalrymple 1986).
Culiacan A82, Navolato A71, CICA4, and Milagro Filipino (IR8) are
planted in the northwest and have long and medium grain, translucence,
and hard texture (L.L. Delgado, Instituto Nacional de Investigaciones
Forestales y Agropecuarias, 1990, pers. commun.). Those in the
Pacific Coast have high volume expansion on cooking: Milagro Filipino,
CICA8, Navolato A71, Campeche A80, Morelos A70, and Morelos
A83. Morelos A70, Morelos A83, and Morelos A88, varieties in the
Central Region, have medium to long grain, and high volume expansion.
Rices on the Gulf of Mexico coast have translucent grain and high
volume expansion (Milagro Filipino, Chetumal A86, Palizada A86,
CICA4, Campeche A80, and Cardenas A80). Those in the Southeast
have translucent grain, hard texture, and high volume expansion:
Palizada A86, Milagro Filipino, CICA4, CICA6, CICA8, Chetumal A86,
Campeche A80, Cardenas A80, and Sureste A90. Nine market samples
have 24-28% AC and low-intermediate GT (RCMD 1987,1989).
High-AC and then intermediate-AC rices predominated among
Mexican varieties (Appendix, Table 6). All of the varieties listed above
that were analyzed had high AC (except Cardenas A80 and Morelos
A70). Joachin A74 was the only low-AC rice. Among the five high-AC
rices, the upland variety Sureste A90 had the softest cooked rice. Longgrained
rices predominated over medium-grained and so did slendershaped
over medium-shaped types.
Cooked rice stickiness correlated significantly with cooked rice
hardness ( r = –0.77**, n = 18), AC ( r = –0.85**), and Amylograph setback
( r = –0.79**) and consistency ( r = –0.83**). Cooked rice hardness also
correlated with Amylograph setback ( r = 0.76**, n = 23) and consistency
( r = 0.77**), alkali spreading value ( r = 0.61**), and protein content
( r = 0.72**). Amylose content correlated with Amylograph setback
( r = 0.68**, n = 23) and consistency ( r = 0.68**) and so did alkali
42 Grain quality evaluation of world rices