Physicochemical property changes in germinated brown rice flour from different storage periods of paddy rice

This study revealed that the storage duration (2, 4, 6, 8, 10 and 12 months) of paddy rice and pH (3 and 6.8) of steeping water during germination were significantly influenced the physicochemical properties of germinated brown rice flour (GBRF). GBRF obtained at pH 3 vs. 6.8 provided the highest both reducing sugar content and free gamma‐aminobutyric acid (GABA) content (99.8 vs. 54.2 mg per 100 g flour respectively) as the paddy rice was stored for 8 months. The peak viscosity of GBRF obtained at pH 3 and 6.8 exhibited the lower values than that of non‐GBRF throughout the storage. From the principal component analysis, reducing sugar had a positive correlation with α‐amylase activity whereas a negative correlation was found with peak viscosity. GBRF from paddy rice stored for 8 months and germinated at pH 3 possessed the highest free GABA content, 50 times of the non‐GBRF, which can be further utilised in functional and healthy foods.     

Effect of Storage Conditions on 2–Acetyl-1–pyrroline Content in Aromatic Rice Variety, Khao Dawk Mali 105

ABSTRACT: The effect of package and temperature on 2–acetyl-1–pyrroline content in milled aromatic rice during storage was investigated. 2 -Acetyl-1 -pyrroline content was decreased faster at higher storage temperature. However, fat acidity of rice was increased during storage and inversely correlated with 2–acetyl-1–pyrroline content at an early stage of storage. The difference in 2–acetyl-1 -pyrroline recovery from the samples, which were extracted with ethanol at 40 °C and 75 °C, revealed that the starch bound and free forms of 2–acetyl-1–pyrroline may occur in aromatic rice. These results suggested that the biosynthesis of 2–acetyl-1 -pyrroline before starch structure formation in rice kernel could play a key role in the aroma quality of aromatic rice.     

Germination Conditions Affect Selected Quality of Composite Wheat-Germinated Brown Rice Flour and Bread Formulations

Abstract: Brown rice has been reported to be more nutritious after germination. Germinated brown rice flours (GBRFs) from different steeping conditions (in distilled water [DI, pH 6.8] or in a buffer solution [pH 3] for either 24 or 48 h at 35 °C) were evaluated in this study. GBRF obtained from brown rice steeped at pH 3 for 48 h contained the highest amount of free gamma aminobutyric acid (GABA; 67 mg/100 g flour). The composite flour (wheat-GBRF) at a ratio of 70 : 30 exhibited significantly lower peak viscosity (PV) (56.99 – 132.45 RVU) with higher alpha-amylase activity (SN = 696 – 1826) compared with those of wheat flour (control) (PV = 136.46 RVU and SN = 1976). Bread formulations, containing 30% GBRF, had lower loaf volume and greater hardness (P < 0.05) than the wheat bread. However, the hardness of bread containing 30% GBRF (except at pH 6.8 and 24 h) was significantly lower than that of bread containing 30% nongerminated brown rice flour (BRF). Acceptability scores for aroma, taste, and flavor of breads prepared with or without GBRFs (30% substitution) were not significantly different, with the mean score ranging from 6.1 (like slightly) to 7 (like moderately). Among the bread formulations containing GBRF, the one with GBRF prepared after 24 h steeping at pH 3 had a slightly higher (though not significant) overall liking score (6.8). This study demonstrated that it is feasible to substitute wheat flour with up to 30% GBRF in bread formulation without negatively affecting sensory acceptance. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 30% germinated brown rice flour in a wheat bread formulation without negatively affecting sensory acceptance. In the current United States market, this type of bread may be sold as frozen bread which would have a longer shelf life. Further study is thus needed.     

Performance Evaluation of Top-Spray Fluidized Bed Coating for Healthy Coated Rice Production

Coating with top-spray fluidized bed at inappropriate operating condition not only provides low product quality but also leads to low coating efficiency and improper energy consumption. The objective of this study was therefore to study the effects of superficial air velocity (Vf), atomization air pressure (Ap), and recycled exhaust air (Ra) on the performance of top-spray fluidized bed coating (TSFBC) in terms of product quality, coating efficiency (CE), and energy consumption for producing turmeric extract coated rice (TECR). The experimental results showed that the operation of TSFBC without Ra provided the final moisture content (MC) of TECR lower than 12 % (wet basis (w.b.)) for all Vf’s and Ap’s. The lowering final MC of TECR below 11.8 % (w.b.) led to the fissure of all TECR kernels. The Ra with 80 % could significantly reduce the number of fissured kernels and the energy consumption of electric heater by 41.7–46.5 %. The operation of TSFBC at low Vf, i.e., 2 m/s, resulted in high number of uncoated white rice kernels (UCWR) for all Ap’s and Ra. When the Vf was increased to 2.5 or 3 m/s, the number of UCWR was significantly reduced and the value of CE was higher than that at 2 m/s. At such both velocities, the Ap and Ra insignificantly affected the CE but the Ra slightly affected the number of UCWR.     

Germination Conditions Affect Physicochemical Properties of Germinated Brown Rice Flour

ABSTRACT:  Germinated brown rice has been reported to be nutritious due to increased free gamma-aminobutyric acid (GABA). The physicochemical properties of brown rice (BR) and glutinous brown rice (GNBR) after germination as affected by different steeping times (24, 36, 48, and 72 h depending on the rice variety) and pHs of steeping water (3, 5, 7, and as-is) were determined and compared to those of the nongerminated one (control). As the steeping time increased or pH of steeping water decreased, germinated brown rice flours (GBRF) from both BR and GNBR had greater reducing sugar, free GABA and α-amylase activity; while the total starch and viscosity were lower than their respective controls. GBRFs from both BR and GNBR prepared after 24-h steeping time at pH 3 contained a high content of free GABA at 32.70 and 30.69 mg/100 g flour, respectively. The peak viscosity of GBRF obtained from both BR and GNBR (7.42 to 228.22 and 4.42 to 58.67 RVU, respectively) was significantly lower than that of their controls (255.46 and 190.17 RVU, respectively). The principal component analysis indicated that the important variables for discriminating among GBRFs, explained by the first 2 components at 89.82% of total explained variance, were the pasting profiles, α-amylase activity, and free GABA.     

Sepsis Encephalopathy Is Partly Mediated by miR370-3p-Induced Mitochondrial Injury but Attenuated by BAM15 in Cecal Ligation and Puncture Sepsis Male Mice

BAM15 (a mitochondrial uncoupling agent) was tested on cecal ligation and puncture (CLP) sepsis mice with in vitro experiments. BAM15 attenuated sepsis as indicated by survival, organ histology (kidneys and livers), spleen apoptosis (activated caspase 3), brain injury (SHIRPA score, serum s100β, serum miR370-3p, brain miR370-3p, brain TNF-α, and apoptosis), systemic inflammation (cytokines, cell-free DNA, endotoxemia, and bacteremia), and blood–brain barrier (BBB) damage (Evan’s blue dye and the presence of green fluorescent E. coli in brain after an oral administration). In parallel, brain miR arrays demonstrated miR370-3p at 24 h but not 120 h post-CLP, which was correlated with metabolic pathways. Either lipopolysaccharide (LPS) or TNF-α upregulated miR370-3p in PC12 (neuron cells). An activation by sepsis factors (LPS, TNF-α, or miR370-3p transfection) damaged mitochondria (fluorescent color staining) and reduced cell ATP, possibly through profound mitochondrial activity (extracellular flux analysis) that was attenuated by BAM15. In bone-marrow-derived macrophages, LPS caused mitochondrial injury, decreased cell ATP, enhanced glycolysis activity (extracellular flux analysis), and induced pro-inflammatory macrophages (iNOS and IL-1β) which were neutralized by BAM15. In conclusion, BAM15 attenuated sepsis through decreased mitochondrial damage, reduced neuronal miR370-3p upregulation, and induced anti-inflammatory macrophages. BAM15 is proposed to be used as an adjuvant therapy against sepsis hyperinflammation.     

Optimal Operating Conditions to Produce Nutritious Partially Parboiled Brown Rice in a Humidified Hot Air Fluidized Bed Dryer

V-type amylose–lipid complexes present in partially parboiled rice can decrease starch digestibility. Formation of such complexes can be accomplished using high-temperature fluidized bed drying; the degree of the complexes depends on the thermal condition. The effects of drying media (hot air and humidified hot air), operating conditions (drying air temperature and relative humidity [RH]), and the initial moisture content on the degree of V-type crystallinity and subsequent starch digestibility (or glycemic index, GI) and brown rice texture were examined experimentally. The results showed that paddy drying with humidified hot air (HHA) requires a longer time than hot air (HA). Higher drying air temperature, RH, and initial moisture content of paddy yield higher degrees of starch gelatinization and V-type amylose–lipid complexes. The brown rice dried by HA or HHA had lower starch digestibility and a harder texture than the reference sample. Within the range of parameters studied, to obtain the lowest GI for the dried brown rice, paddy at an initial moisture content of 33% (db) should be dried by HHA at 150°C and 6.4% RH.     

Mevinolin, citrinin and pigments of adlay angkak fermented by Monascus sp

Adlay angkak a new developed product from an adlay substrate fermented by Monascus fungi can be used both as a natural coloring and a dietary supplement. However, not only useful secondary metabolites such as mevinolin and pigments are produced; the fungi also produce toxin substance called citrinin. This study conducted the cultivation of M. purpureus (ATCC 16365, BCC 6131, DMKU and FTCMU) and M. ruber TISTR 3006 on the adlay substrate for mevinolin, citrinin, pigments and glucosamine synthesis at room temperature (32-35 degrees C) for 28 days. The results elucidated that glucosamine levels expressed as the mold growth in solid-state fermentation corresponded as a relatively reliable indicator to the mevinolin, citrinin and pigments production. M. purpureus DMKU produced the lowest citrinin content of 0.26 ppm and the highest mevinolin content of 25.03 ppm with pigment concentrations expressed by absorbance at wavelengths of 400, 470 and 500 nm for yellow, orange and red pigments of 9.76, 3.03 and 3.43 units respectively and moisture content and pH of 83.51% and 6.54 respectively. This study suggested that M. purpureus DMKU has a potential for the production of adlay angkak within an authorized citrinin level.     

Effects of cooking, drying and pretreatment methods on texture and starch digestibility of instant rice

Instant rice produced from a conventional process consisting of the cooking, washing and drying steps possesses poorer eating quality compared with that of freshly cooked rice. The objective of this work was therefore to study the effects of cooking, pretreatment and drying methods on microstructure, textural properties and starch digestability of instant rice after rehydration; jasmine white rice was chosen as a test material. Conventional boiling method and electric rice cooking were selected as the methods to prepare cooked rice. In the case of boiling, cooked rice was frozen at −20 °C or cooled at 4 °C for 24 h prior to drying, while the cooked rice from an electric rice cooker was washed with ambient or cool water for 30 s prior to drying. After pretreatment the cooked rice was dried either by freeze drying or hot air drying at 80 °C. Based on the scanning electron microscopic results it was found that the cooking, pretreatment and drying methods all affected the rice morphology. The hardness and stickiness of instant rice after rehydration were lower for samples prepared from the rice cooker than those of freshly cooked rice, while both textural properties appeared to be improved significantly for the samples from boiling. The texture of the freeze-dried products was not different from that of the air-dried one. The freezing pretreatment provided the texture and glycemic index of instant rice after rehydration similar to those of the freshly cooked rice. On the other hand, the cooling pretreatment resulted in the harder texture and higher glycemic index of the samples.