密封包装米飯におけるＡおよびＢ型ボツリヌス菌の毒素産生に及ぼすｐＨの影響と芽胞の耐熱性

As it is obliged that cultivars, location and year of production should be displayed on bag of milled rice grains, technology to identify them by the objective methods is indispensable. Milled rice grains produced at the several agricultural experiment stations were subjected to the RAPD method. Each DNA was extracted by CTAB method and amplified by PCR method using 10 mer primers. It became possible to identify the rice cultivars using milled rice grains as samples by the electrophore-sis of the PCR products among the dominant 10 rice cultivars in Japan.

Rice is a staple food in many countries. The price of rice depends on the qualities that are often quantified based on color, size, and presence of some regional color information. In the Philippines, the National Food Authority released the National Grain Standards for milled rice grains to facilitate the uniform classification of rice. The standards specify the grades: Premium and Grade 1-5 to grade milled rice grain samples based on the number of immature, red, fermented, chalky grains, and others, present in the sample. This study aimed to design and develop a standalone system capable of grading rice samples using grain validation, color and area analysis, and support vector machines with adaptive boosting. The image acquisition platform was created to provide a constant lighting setting and an enclosed staging platform capable of extracting an average of fifty grain images per sample. Seven support vector machine classifiers boosted with adaptive boosting, one chalky classifier, one grain size classifier, were created, trained, and tested. Feature vectors for the SVMs were histogram of gradients features and the color histogram properties: mean, skew, and dominant. The evaluation of the device resulted with an overall micro-average precision of 0.8667 and a micro-average recall of 0.8667 with an Fl-Score of 0.8667.

Rice is a very important item of food and commerce in Sierra Leone and so information o n the quality of available rice grains can serve as a useful indicator for the technical status and level of competitiveness in the local rice industry . During this study a n objective evaluation was conducted to measure and characterize the quality of rice grains available in the local markets of Sierra Leone. A total of 315 randomly selected rice samples from 45 markets selected from the four major cities of Sierra Leone (Makeni, Bo, Kenema and Freetown, representing urban communities from the northern, southern, eastern and western parts of the country , respectively ) were evaluated. Quality evaluation involved measurement of moisture content, number of paddy (unmilled rice kernels) in 1 kg of milled rice and other quality factors normally used for the grading of milled rice. Rice samples were then graded based on criteria adapted from the Philippines Rice Grading Standards for milled rice grains. The results showed that the quality of all grain samples evaluated was generally poor, with 63.2% of the samples failing to meet the criteria set for Grade III rice quality ( meaning that the quality level was worse than grade III ) . Quality measures obtained for imported samples appeared to be superior to that obtained for the local samples in terms of higher proportions of superior grades (grade II or better ) . Comparison of measures of grading factors revealed that among the four cities considered in this study, grains from Kenema were of the lowest quality . Further examination of grade limiting factors revealed that the most critical factors responsible for poor quality outcomes in grain sample were (i) the number of paddy in 1kg of milled rice and (ii) the moisture content of grains . The study provided quantitative measures of the quality status of rice grains available in Sierra Leone , as well as a means of identifying the major binding constraints to rice grain quality, in terms of the grade limiting factors. It is speculated that t he low quality of rice grains observed in this study could be the result of avoidable quality defects that may be linked to an undeveloped national system for rice milling and handling .

A possible mechanism of mineral responses to elevated atmospheric CO2 in rice grains

ABSTRACT: Chemometric formulas for predicting amylose content (AC) and protein content (PC) were developed based on the surface and overall physical properties of single‐cooked milled rice grains as predictive variables. The formula with 8 predictors for AC determination exhibited the highest accuracy (coefficient of determination: R2= 0.952, standard error of calibration: SEC = 1.77) for calibration and the lowest standard error of prediction (SEP = 2.07) for unknown samples (AC: 0 to 30%). The formula with 7 predictors was effective in enhancing the prediction accuracy (SEP = 1.32) among non‐waxy samples in a narrow range of AC (15 to 20%). The formula with 8 predictors for PC determination showed a higher accuracy (R2= 0.449 and 0.470) for both calibration and prediction than that of a conventional 3‐grain method (R2= 0.168 and 0.124). It was possible to accurately determine AC using physical measurement of single grains instead of chemical analysis.

The consumption of resistant starch (RS), which can increase satiety and reduce calorie intake, may help ameliorate lifestyle‐related diseases such as diabetes, hypertension, and obesity. The identification of genes or quantitative trait loci (QTLs) may facilitate improvement in the amounts and properties of RS in cereals such as rice. A genome‐wide association mapping of the RS content in milled rice grain was carried out to identify QTLs in a rice germplasm collection. The RS contents among 105 rice accessions ranged from 0.3 to 2.42%, and the apparent amylose content (AAC) was positively correlated with the RS content (R2 = 0.75). Four QTLs were detected, and each explained a total phenotypic variation of 10–13%. Two of these, on chromosome 6, were identified at the Waxy gene locus encoding granule‐bound starch synthase I and starch synthase IIa. The other two QTLs, on chromosomes 8 and 9, were close to candidate genes encoding the starch debranching enzyme isoamylase I and ADP‐glucose pyrophosphorylase small subunit 1, respectively. The results of this study should improve our understanding of the genetic basis of RS in milled rice and may assist plant breeders attempting to develop new rice varieties and food processors working to develop functional foods.

Using Check-All-That-Apply (CATA) method for determining product temperature-dependent sensory-attribute variations: A case study of cooked rice

Pathum Thani 1 (PTT1) is a photoperiod-insensitive, aromatic Thai rice variety that is grown year-round. The rice from some locations is often priced lower than others due to sub-standard grain quality. This study sought to determine the limiting grain quality characteristic(s) in dry season PTT1 and their distribution across Thailand's irrigated rice regions. To do so, we evaluated the milling and physical quality of milled rice grain of dry season PTT1 from 24 provinces in 5 regions in Thailand. Sixty-seven paddy rice samples were collected and evaluated for head rice yield, chalkiness, whiteness, and translucency. Head rice yield varied by region, with the highest (48.1%) found in samples from the Central region, compared to 34.5-39.7% elsewhere. Head rice chalkiness was the physical quality that varied more widely among the provinces within each region than among regions, with chalkiness at a level that would adversely affect price in more than one-half of the samples. Contrary to the general perception that chalky grain is less resistant in milling, head rice yield actually increased with total chalkiness, expressed as % chalky grain by weight. The total chalkiness correlated negatively with translucency, while the head rice chalkiness correlated positively with whiteness. Grain chalkiness was identified as the grain quality attribute of PTT1 rice that varied with location; this directly affected the price of milled rice grain, as well as indirectly through its relationship with head rice yield and visual appearance of the milled rice grain.

Evaluation of the Effect of Acetylsalicylic Acid on Clostridium botulinum Growth and Toxin Production

The combined effect of low temperature and low pH on survival of, and growth and toxin formation from, spores of Clostridium botulinum

Rice is a staple food of human and can be a main source of arsenic (As) exposure. This study was conducted to i) investigate the concentrations of total, inorganic and bioaccessible of As in raw rice, ii) investigate the effects of rice processing before human consumption on the concentrations of As in rice, and iii) evaluate the potential health impacts of As exposure through rice consumption. A total of 208 polished and non-polished samples sold in the local markets of Bangkok were collected. The total As concentrations in polished (0.0878 to 0.2949 mg kg-1, n = 154) and non-polished (0.1187 to 0.51722 mg kg-1, n = 54) were determined. The percentages of inorganic As to total As in rice were 58% and 52% in polished and non-polished rice, respectively. Approximately 25% of total As in 8% DOP rice grain were significantly reduced compared to the total As in non-polished rice (0% DOP) (p < 0.01). Only 3-time washing could significantly decrease total As concentration in polished rice (p < 0.05) by approximately 29%. Washing did not effectively remove As from non-polished rice grain. Rice washed for 3 times and then cooked with the traditional and modern cooking method using an aluminum pot and an electric rice cooker, respectively, had approximately 60% and 21% of total As reduction comparing to the raw rice. Cooked rice from both cooking methods had significantly lower As bioaccessibility than the raw rice. The deterministic and probabilistic risk assessment results of bioaccessible As exposure through the consumption of modern cooked rice indicated a negligible non-carcinogenic effects in the majority of children, adolescents, and adults as the hazard quotients in all groups were less than 1. Adults were susceptible population to carcinogenic effects especially from the non-polished rice consumption. The average cancer risk which was approximately 1.12×10-4 exceeded the acceptable cancer risk of 1×10-4. Three important factors affecting the health risk levels were rice ingestion rate, individual body weight, and As concentration in cooked rice.

The dithizone method was applied for the determination of total mercury and organomercury in organomercury fungicides. Paper chromatography was applied for separation and identification of organomercury compounds in fungicide formulation. Gas chromatography with thermal conductivity detector was applied for the determination of D-D, EDB, DBCP, chloropicrin, DDVP, aldrin, dieldrin, chlorobenzilate, BHC isomers, nicotine sulfate, diazinon, heptachlor, VC-13, 2, 4-D ethyl ester, PCP, DBN, DCPA and PCNB in those formulation.An improved A. O. A. C. method by dithizone was applied for the determination of mercury residues in rice grains, fruits and tea leaves treated with organomercury fungicides. The amounts of mercury residues in raw rice grains treated with fungicide ranged from 0.04 to 0.84ppm, and influenced by mainly the lapse days after application. About 60% of mercury residues in raw rice grains was found in pollished grains and remaining 40% was in bran. The more high water solubility and hardly dissociated into ions the compounds has, the more uptake of mercury by rice plant from soil treated with those mercury compounds. Subsequently gas chromatography with electron capture detector was applied for the determination of organochlorine insecticides residues in various crops. The amounts of total BHC residues in raw rice grains treated with BHC dust ranged from 0.41 to 1.42ppm. Afterwards, from the similar purpose, on the relationship between the amounts of DDT and its derivatives residues in rice grains and apples and the history of application were examined under the field conditions.At finally, the biological concentration ratio (BCR) of the fourteen pesticides by fresh water fish, topmouth gudgeon were determined at the equilibrium condition under the continuous flow water system containing about 10ppb of those pesticides. These BCR obtained by this experiment were correlated to the octanol/water partition coefficient of individual compounds and inversely proportional to the water solubility. Therefore, it is able to predict the biological concentration potential of pesticide by means of these two physicochemical properties.

The influence of adding clostridial spores to silage was studied in 2 successive years. Direct‐cut, precision‐chopped herbages were infected with spores of Clostridium tyrobutyricum in doses varying from 0 to 106 g−l fresh material (FM), and ensiled in experimental silos. The material was treated with or without 4 ml formic acid (85%) kg−1 FM. Silo contents were studied after 4.20 (or 50) and 100 days of ensiling.Contents of dry matter, water‐soluble carbohydrate, nitrate as well as buffering capacity of FM varied between the 2 years at harvest, whereas the numbers of clostridial spores were about the same (< 102 g−1).Infecting the crop with clostridial spores negatively affected the quality of silage in the first year. After 50 days spore numbers in the silages had increased by 40 × 103 to 150 × 103 times in the infected silage, compared with 5 × 103 in the uninfected silage. No effect was seen in the second year.Silage with high spore counts showed no residual nitrate content. Formic acid improved silage quality from a chemical point of view but had no anti‐clostridial effect. Ensilability of a crop seems to be more important than the initial count of Clostridia for a successful ensiling process.

Effects of Storage Period, Milling Degree of Stored Brown Rice Grains, and Soaking of Milled Rice Grains on the Properties of Cooked Rice Grains

Quality controlling of brown rice by ultrasound treatment and its effect on isolated starch