Effect of Rice Chilling on Drying, Milling, and Quality Characteristics

2020 ◽  
Vol 36 (5) ◽  
pp. 767-776
Author(s):  
Soraya Shafiekhani ◽  
Griffiths G Atungulu
Keyword(s):  
High Temperature ◽  
Cold Storage ◽  
Storage Temperature ◽  
Rice Yield ◽  
Quality Characteristics ◽  
List Type ◽  
Milled Rice ◽  
Heated Air ◽  
Rough Rice

HighlightsThis study experimentally simulated drying of rough rice subjected to various cold storage/chilling conditions.The rice was dried using slightly-heated air and high temperature air with procedures set to mimic those practiced by commercial systems.The moisture removal, drying rate constant, material state transition, milling and quality characteristics of rice upon drying conditions was investigated.The study provides important reference information for growers and rice processors using the relatively new rice cooling technology.Abstract. High temperature (field heat) and moisture content of freshly harvested rough rice promote excessive respiration and microbial growth. Therefore, the rice risks significant deterioration of quality due to delayed drying at peak harvest time when drying capacity becomes limited. The U.S. rice industry has identified that cooling/chilling the rice prior to drying to remove the excess heat, immediately after harvest, significantly preserves the quality of milled rice. This study experimentally simulated drying of rough rice after cold storage/chilling. The rice was dried using slightly-heated air and high temperature air with procedures set to mimic those practiced by commercial systems. Rough rice at moisture contents (MCs) of 16%, 19%, and 21% (wet basis) were stored at storage temperature (Ts) of 10°C, 15°C, and 20°C for up to 4 months. Following retrieval, the samples were dried at drying temperature (Td) of 35°C, 45°C, and 60°C and relative humidity (RH) of 20%. Each drying run comprised of two 20-min drying passes with the rice tempered at the drying Td for a duration of 4 h following every drying pass. Following the drying, the rice was conditioned in an equilibrium MC chamber (T=26°C, RH=56%) to 12.5% MC and then milled to evaluate milled rice yield and quality characteristics. The highest percentage points of MC removal (6.77% points) occurred following drying at air temperature of 60°C for samples with initial MC at 21% and stored at 20°C. Drying with air at 60°C decreased head rice yield (HRY) especially for samples with initial MC at 21% and stored at 10°C (HRY=51.4% versus those at 45°C and 35°C, HRY=55.95% and HRY=58.8%, respectively). Drying air temperatures studied (35°C, 45°C, 60°C) had no significant effect of causing discoloration of samples within the range of the studied initial MCs and storage temperatures. Peak and final viscosities of samples with different initial MCs (16%, 19%, and 21%) stored at 20°C followed by high temperature air drying (60°C) were significantly different from those of samples stored at 10°C and 15°C. The results provided insight into the drying, milling, and quality characteristics of rice after cold storage/chilling. The information provide foundation for development of new recommendations to improve quality of milled rice. Keywords: Conventional drying, Cooling/chilling, Milling quality, Rough rice, Storage.

Prediction of Rice Milling Yield and Quality Attributes during Storage Using Regression Analyses

2019 ◽  
Vol 62 (5) ◽  
pp. 1259-1268
Author(s):  
Soraya Shafiekhani ◽  
Jung Ae Lee ◽  
Griffiths G. Atungulu
Keyword(s):  
Hybrid Rice ◽  
Storage Temperature ◽  
Rice Yield ◽  
Storage Conditions ◽  
Milled Rice ◽  
Yield And Quality ◽  
Head Rice ◽  
Rough Rice ◽  
Milling Yield

Abstract. Regression analyses were performed to determine the storage conditions that exhibited the best outcomes for long-grain, hybrid milled rice yield and quality. This study evaluated mold population on rough rice, milled rice discoloration, and head rice yield (HRY) after storage of rough rice in airtight conditions at moisture contents (MCs) of 12.5%, 16%, 19%, and 21% wet basis and temperatures of 10°C, 15°C, 20°C, 27°C, and 40°C at two-week intervals for 12 weeks. The experiment used a popular long-grain hybrid rice cultivar (XL745). Rice lots were procured from fields with and without conventional treatment of the field with fungicide for plant disease management. Field treatment and no field treatment were considered as a block, and a Mann-Whitney test was conducted to determine effect. The response surface method, an extension of second-order polynomial regression, was used to examine optimal treatment conditions. Mold population and milled rice discoloration from a combination of storage conditions were predicted using regression models. The first-order and second-order terms of temperature indicated a nonlinear relationship between temperature and ln(discoloration). The MC was positively associated with ln(discoloration), but the degree of impact may change with temperature because the interaction term was significant. From the model evaluation (R2 and lack-of-fit test), the discoloration level is expected to be 57% (49% to 66% confidence interval) under conditions of 20% MC, 40°C, and nine weeks of storage for samples procured from fungicide-treated rice fields. This discoloration change is substantial compared to the initial discoloration of 9%. At high temperature (40°C) and MC (21%), discoloration started immediately after two weeks of storage. Anaerobic storage conditions impeded mold growth, especially at high storage temperature (40°C). Low mold populations were observed in rice stored at low MC (16%). According to the regression model, the critical storage temperature that may lead to discoloration is between 27°C and 40°C. Pre-harvest fungicide treatment of rice in the field for disease control significantly improved the HRY but had no significant influence on mold population or discoloration. This study suggests a range of storage conditions to prevent losses in milling yield and quality of rice. In addition, the studied storage conditions mimicked the typical conditions for on-farm, in-bin drying and storage in the U.S. Mid-South, especially for the top layers of rice inside the bin, and therefore provide an important reference for growers and rice processors using in-bin structures to manage the quality of long-grain hybrid rice. Keywords: Discoloration, Head rice yield, Mold population, Regression analysis, Rice quality, Rice storage.

Physical Integrity of Long-Grain Hybrid, Pureline, and Medium-Grain Rice Kernels as Affected by Storage Conditions

2020 ◽  
Vol 36 (4) ◽  
pp. 579-588
Author(s):  
Zeinab Mohammadi Shad ◽  
Griffiths Atungulu
Keyword(s):  
Sodium Chloride ◽  
Storage Temperature ◽  
Rice Yield ◽  
Storage Conditions ◽  
List Type ◽  
Milled Rice ◽  
Physical Integrity ◽  
Head Rice ◽  
Head Rice Yield ◽  
The Impact

Highlights Rice kernel physical integrity diminished at higher storage temperature and moisture content. Variation in rice kernel physical integrity was noticeable among rice cultivars. Fungal attack lessened rice kernel physical integrity. Abstract . Rice kernel physical integrity directly correlates with rice milling yield and quality. In this study, the impact of storage conditions on rice kernel physical integrity was examined by assessing changes in head rice yield (HRY) and kernel microstructure. Long-grain hybrid (XL753), long-grain pureline (Roy J), and medium-grain (Titan) rice were stored at different storage moisture contents (16% and 21% MCs, wet basis), storage temperatures (20°C, 30°C, and 40°C), and storage durations (4, 8, 12, and 16 weeks); the samples were also treated with antifungals, sodium chloride, and natamycin. Results show that kernel physical integrity was highly dependent on the rice storage environment. At the same storage conditions, the physical integrity of medium-grain cultivar was significantly higher than that for the two long-grains. Generally, the long-grain hybrid rice exhibited more resilience to breakage than pureline under the same storage conditions. An average of 4% reduction in HRY was seen for the three cultivars when 16% MC rice was stored at 40°C compared to at 20°C; however, the HRY reduction was 12% for rice stored at the highest MC (21%). Decreases in kernel physical integrity were also associated with unique microstructural changes in rice kernels. Sodium chloride treatment of rice kernels significantly and negatively impacted their physical integrity during storage compared to natamycin treatment and untreated control samples. Multiple regression models, developed for each cultivar were applicable for predicting changes in rice kernel physical integrity as a function of studied storage conditions and antifungal treatments. Keywords: Antifungal treatment, Head rice yield, Microstructure, Milled rice quality, Storage, Rice kernel physical integrity.

scholarly journals Evaluasi Penyimpanan Spermatozoa Ayam Pada Suhu 5⁰C, 26⁰C Dengan Pengencer Infuse NaCl, Glukosa 5% dan 10%

2021 ◽  
pp. 10-19
Author(s):  
Asnawi Asnawi ◽  
Maskur Maskur ◽  
Adji Santoso Dradjat
Keyword(s):  
Cold Storage ◽  
Room Temperature ◽  
Storage Temperature ◽  
Room Temperature Storage ◽  
C Storage ◽  
Better Than ◽  
Temperature Storage

The purpose of this study were to compare the quality of spermatozoa stored at 26⁰C, 5⁰C using diluents of NaCl, 10% glucose and 5% glucose. The spermatozoa of a rooster was collected and divided into 6 parts, each 2 tubes diluted in a ratio of 1:1 using NaCl, Glucose5% and Glucose 10%, then each 3 tubes with different diluents were stored at 26⁰C and 5⁰C. Observations of motility, viability and abnormalities of spermatozoa were carried out half an hour, 1 hour after dilution, followed every 2 hours until the ninth hours. The results showed that spermatozoa stored for 9 hours at a temperature of 26⁰C with a physiological diluent of NaCl, 10% Glucose and 5% Glucose each were different (P, < 0.05) with motility 50 ± 0.0%, 42 ± 10.95. % and 34±8.94%, respectively. At storage temperature of 5⁰C for 9 hours, physiological NaCl, 10% glucose and 5% glucose were significantly different (P<0.05) with motility 58.00±10.95%, 46.00±8.94% and 38.00±, respectively. 10.95% in a row. The viability of spermatozoa at 26⁰C storage with 5% glucose diluent was better than 10% glucose and physiological NaCl (P<0.05), 58.93±1.27%, 42.93±1.48% and 33.43±1.27% , while the physiological NaCl diluent and 10% glucose were not significantly different (P>0.05). At 5⁰C storage the viability of spermatozoa in the three diluents was not significantly different, with values of Glucose 10%, Glucose 5% and physiological NaCl 52.57±5.15%, 52.21±5.02% and 48.14±8.09%, respectively. Spermatozoa abnormalities at storage temperature 26⁰C and 5⁰C for 9 hours using physiological NaCl diluent, 5% glucose and 10% glucose, were not significantly different and varied between 5 to 10%. Finally, it can be concluded that at room temperature storage less than 4 hours the quality of spermatozoa was better with 5% glucose diluent, while for cold storage beyond 4 hours the quality of spermatozoa with NaCl diluent was higher

scholarly journals Gibberellin4+7, Benzyladenine, and Supplemental Light Improve Postharvest Leaf and Flower Quality of Cold-stored `Stargazer' Hybrid Lilies

1998 ◽  
Vol 123 (4) ◽  
pp. 563-568 ◽  
Author(s):  
Anil P. Ranwala ◽  
William B. Miller
Keyword(s):  
Cold Storage ◽  
Storage Temperature ◽  
Postharvest Quality ◽  
Flower Longevity ◽  
Flower Bud ◽  
Leaf Injury ◽  
Leaf Chlorosis ◽  
Bud Opening ◽  
Flower Quality

Experiments were conducted to evaluate storage temperature, storage irradiance and prestorage foliar sprays of gibberellin, cytokinin or both on postharvest quality of Oriental hybrid lilies (Lilium sp. `Stargazer'). Cold storage of puffy bud stage plants at 4, 7, or 10 °C in dark for 2 weeks induced leaf chlorosis within 4 days in a simulated consumer environment, and resulted in 60% leaf chlorosis and 40% leaf abscission by 20 days. Cold storage also reduced the duration to flower bud opening (days from the end of cold storage till the last flower bud opened), inflorescence and flower longevity, and increased flower bud abortion. Storage at 1 °C resulted in severe leaf injury and 100% bud abortion. Providing light up to 40 μmol·m-2·s-1 during cold storage at 4 °C significantly delayed leaf chlorosis and abscission and increased the duration of flower bud opening, inflorescence and flower longevity, and reduced bud abortion. Application of hormone sprays before cold storage affected leaf and flower quality. ProVide (100 mg·L-1 GA4+7) and Promalin (100 mg·L-1 each GA4+7 and benzyladenine (BA)) effectively prevented leaf chlorosis and abscission at 4 °C while ProGibb (100 mg·L-1 GA3) and ABG-3062 (100 mg·L-1 BA) did not. Accel (10 mg·L-1 GA4+7 and 100 mg·L-1 BA) showed intermediate effects on leaf chlorosis. Flower longevity was increased and bud abortion was prevented by all hormone formulations except ProGibb. The combination of light (40 μmol·m-2·s-1) and Promalin (100 mg·L-1 each GA4+7 and BA) completely prevented cold storage induced leaf chlorosis and abscission.

X-Ray Detection of Fissures in Rough Rice Kernels

2017 ◽  
Vol 33 (5) ◽  
pp. 721-728 ◽  
Author(s):  
Zephania R. Odek ◽  
Bhagwati Prakash ◽  
Terry J. Siebenmorgen
Keyword(s):  
Rice Yield ◽  
X Rays ◽  
Milled Rice ◽  
Substantial Impact ◽  
X Ray ◽  
X Ray Imaging ◽  
Head Rice ◽  
Rough Rice ◽  
Head Rice Yield ◽  
Rice Drying

Abstract. X-ray imaging is a viable method of fissure detection in rough rice kernels owing to the ability of X-rays to penetrate hulls, thus allowing visualization of internal rice kernel structure. Traditional methods of fissure detection are only applicable for brown and milled rice, and therefore cannot be used to study fissures developed during rough rice drying. In this study, the fissure detection capability of an X-ray system was evaluated and the relationship between head rice yield (HRY), as measured through laboratory milling, and the percentage of fissured rough rice kernels was determined. Long-grain rice lots of various cultivars were dried using heated air at 60°C, 10% relative humidity (RH) for five drying durations to produce different degrees of fissuring, and then milled to determine HRY. A strong linear correlation (R2 = 0.95) between HRY and the percentage of fissured rough rice kernels after drying was determined. This correlation confirms the substantial impact that kernel fissures have on milling yields. Overall, these findings show the effectiveness of X-ray imaging in rough rice fissure detection, which could allow for drying research that may provide a better understanding of kernel fissuring kinetics. Keywords: Fissures, Grainscope, Head rice yield, Rice drying, X-ray imaging.

Effect of Storage Moisture Content on Milling Characteristics of Rough Rice

2019 ◽  
Vol 62 (4) ◽  
pp. 1011-1019
Author(s):  
Bhagwati Prakash ◽  
Terry J. Siebenmorgen ◽  
Kristen E. Gibson ◽  
Shweta Kumari
Keyword(s):  
Moisture Content ◽  
Rice Yield ◽  
Surface Lipid ◽  
Milled Rice ◽  
Financial Return ◽  
Head Rice ◽  
Rough Rice ◽  
Head Rice Yield ◽  
Milling Characteristics ◽  
The Mean

Abstract. Rough rice in the Mid-South U.S. is typically stored and milled at a moisture content (MC) between 12% and 13% on a wet basis. Drying harvested rice to lesser MCs requires increasingly greater energy and reduces the overall mass of rice, both of which translate into lesser financial return for the crop. Considering these disadvantages of drying and storing rice at lesser MCs, farmers and grain handlers have been interested in exploring storing rice at slightly greater MCs. The current study was undertaken to evaluate the effect of storing rice at five MCs (11%, 12%, 13%, 14%, and 15%) on milling characteristics, particularly surface lipid content (SLC), milled rice yield (MRY), and head rice yield (HRY); additionally, the effects of storing rice at two storage temperatures (25°C and 35°C) and several storage durations (up to one year) on milling characteristics were investigated. Five long-grain rice lots were harvested in 2016 and 2017 from several locations in Arkansas; rice from each lot was gently dried to the target MCs and then stored in sealed glass jars at selected temperatures. With an increase in storage MC, shorter milling durations were needed to achieve a given SLC, which could potentially reduce the cost of the milling operation. However, rice samples stored at greater MCs were observed to have lesser HRYs, which could reduce the economic value of rice. The mean HRYs of the 15% MC samples were 4.8 to 9.1 percentage points less than the mean HRYs of the 12% MC samples. This study quantifies the milling characteristics of rice when stored for various durations at different MCs and temperatures. Overall, these data will allow the rice industry to make informed decisions related to storage conditions of rice, specifically storage MC. Keywords: Head rice yield, Milling, Moisture content, Rice, Storage.

Effect of Different Packaging Methods and Storage Temperature on Microbiological and Physicochemical Quality Characteristics of Meatball

2010 ◽  
Vol 16 (3) ◽  
pp. 259-265 ◽  
Author(s):  
I. Yilmaz ◽  
M. Demirci
Keyword(s):  
Storage Time ◽  
Storage Temperature ◽  
Microbiological Quality ◽  
Thiobarbituric Acid ◽  
Quality Characteristics ◽  
Modified Atmosphere ◽  
Physicochemical Changes ◽  
Negative Factors ◽  
And Storage

The objective of this research was to determine physicochemical changes and microbiological quality of the different packaged meatball samples. Meatball samples in polystyrene tray were closed with polyethylene film (PS packs), vacuumed and modified atmosphere packaged, (MAP) (65% N2, 35% CO2), and held under refrigerated display (4 °C) for 8, 16 and 16 days for PS packs, vacuum and MAP, respectively. Microbial load, free fatty acids and thiobarbituric acid values of the samples tended to increase with storage time. Bacteria counts of the raw meatball samples increased 2 log cycles at the end of storage compared with initial values. Meatball samples can be stored without any microbiological problem for 7 days at 4 °C. Results from this study suggested that shelf-life assigned to modified-MAP and vacuum-packed meatballs may be appropriate. Meatball samples underwent physical deformation when they were packed before vacuum process. With these negative factors considered, MAP is superior to other two packs methods.

scholarly journals NIR Spectroscopy Detects Chlorpyrifos-Methyl Pesticide Residue in Rough, Brown, and Milled Rice

2020 ◽  
Vol 36 (6) ◽  
pp. 983-993
Author(s):  
Fatima S Rodriguez ◽  
Paul R Armstrong ◽  
Elizabeth B Maghirang ◽  
Kevin F Yaptenco ◽  
Erin D Scully ◽  
...  
Keyword(s):  
Pesticide Residue ◽  
Brown Rice ◽  
Nir Spectroscopy ◽  
List Type ◽  
Pesticide Level ◽  
Milled Rice ◽  
Near Infrared Reflectance ◽  
Independent Validation ◽  
Rough Rice ◽  
Rice Samples

HighlightsNIR spectroscopy detects quantitative and qualitative levels of chlorpyrifos-methyl residues in bulk rice.Levels of chlorpyrifos-methyl residues in bulk rice can be differentiated at 78% to 100% correct classification.Important NIR wavelengths for chlorpyrifos-methyl residue detection were identified.NIR spectroscopy can be used to detect maximum residue levels of chlorpyrifos-methyl pesticide in rice.Abstract. A rapid technique that uses near-infrared reflectance (NIR) spectroscopy for simultaneous qualitative and quantitative determination of the presence of varying concentrations of chlorpyrifos-methyl in bulk samples of rough, brown, and milled rice was established. Five rice varieties, free of pesticides, obtained from RiceTec Inc. and USDA-ARS Arkansas experimental field were used as rough rice samples and also processed to obtain corresponding brown and milled rice. Rice samples were treated with StorcideTM II containing varying levels of the active ingredient, chlorpyrifos-methyl: 0, 1.5, 3, 6, 9, and 12 ppm for rough rice, 0, 0.75, 1.5, 3, 4.5, and 6 ppm for brown rice, and 0, 0.1, 0.2, 0.4, 0.6, and 0.8 ppm for milled rice. Concentrations of chlorpyrifos-methyl were verified using gas chromatography-mass spectrometry analyses. A commercial NIR spectrometer (950-1650 nm wavelength range) was used to obtain spectra of bulk samples. Using partial least squares analysis for quantitative analysis, independent validation showed that chlorpyrifos-methyl residues in rough, brown, and milled rice are predictable with R2 ranging from 0.702 to 0.839 and standard error of prediction (SEP) of 1.763 to 2.374 for rough rice, R2 ranging from 0.722 to 0.800 and SEP of 0.953 to 1.168 for brown rice, and R2 ranging from 0.693 to 0.789 and SEP of 0.131 to 0.164 for milled rice. For qualitative analysis obtained using discriminant analysis, rough rice samples with concentrations of 0, 1.5, and 3 ppm pooled as low pesticide level (LPL) is distinguishable to 6, 9, and 12 ppm which were pooled as high pesticide level (HPL). Similarly, for brown and milled rice, the lower three concentrations pooled as LPL is distinguishable from the higher three concentrations pooled as HPL. Independent validation showed overall correct classifications ranging from 77.8% to 92.6% for rough rice, 79.6% to 88.9% for brown rice, and 94.4% to 100% for milled rice. Keywords: Food safety, Grain quality, NIR spectroscopy, Pesticide residue, Rice.

Understanding Pre- and Post-Milling Crack Formation in Rice Grain

2021 ◽  
Vol 64 (6) ◽  
pp. 1795-1804
Author(s):  
Prakash Oli ◽  
Mark Talbot ◽  
Peter Snell
Keyword(s):  
Crack Formation ◽  
Moisture Absorption ◽  
Rice Yield ◽  
Consumer Acceptability ◽  
Rice Grain ◽  
List Type ◽  
Head Rice ◽  
Before And After ◽  
The Impact

HighlightsCracking and subsequent breakage of rice kernels reduces the marketability and profitability of rice.Pre-milling cracks in rice kernels cause breakage during milling, thereby reducing consumer acceptability.Three types of post-milling cracks reported are: surface, internal, and Hanasaki cracks.Post-milling cracks can be minimized throughout the supply chain.Abstract. Rice is consumed as intact grain, and any broken grains are discounted from the main marketable product. Breakage of rice mainly arises from cracks formed in the endosperm before or after milling. The cracks are formed by stress gradients that arise due to moisture absorption or desorption by grains. As a result of such stress, cracks mostly develop in a direction perpendicular to the length of the grain, making it less physically resistant to the stresses of milling, handling, and soaking processes. Until now, research into rice cracking has mainly focused on minimizing breakage during milling, and no significant knowledge is available on the impact and mechanisms of post-milling cracking and/or breakage and its effect on the downstream quality of rice. This article aims to review the existing information on the causes of rice cracking before and after milling. Keywords: Breakage, Crack, Drying, Glass transition temperature, Hanasaki, Head rice yield, Rice, Tempering.

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