Many research papers on crop water requirements of vegetables have been produced since the publication of the FAO56 guidelines in 1998. A review of this literature has shown that determination of crop evapotranspiration (ET c ) using the K c -ET o approach, i.e., the product of the specific crop coefficient (K c ) by the reference evapotranspiration (ET o ), is the most widely-used method for irrigation water management. Consequently, a review was made to provide updated information on the K c values for these crops. The reviewed research provided various approaches to determine K c in its single and dual versions. With this purpose, actual crop ET (ET c act ) was determined with lysimeters, or by performing the soil water balance using measured soil water content and computational models, or by using Bowen ratio energy balance and eddy covariance measurements, or by using remote sensing applications. When determining the basal K c (K cb ), the partitioning of ET c act was evaluated using different approaches, though mainly using the FAO56 dual K c method. Since the accuracy of experimentally-determined K c and K cb values depends upon the procedure used to compute ET o , as well as accuracy in determining and partitioning of ET c act , the adequacy of the measurement requirements for each approach was carefully reviewed. The article discusses in detail the conceptual methodology relative to crop coefficients and the requirements for transferability, namely distinguishing between actual and standard K c and the need to appropriately use the FAO segmented K c curve. Hence, the research papers selected to update and consolidate mid-season and end-season standard K c and K cb were those that computed ET o with the FAO56 PM-ET o equation; and that also used accurate approaches to determine and partition ET c act for pristine, non-stressed cropping conditions. Under these experimental conditions, the reported K c and K cb values relative to the mid-and end-season could be considered as transferable standard K c and/or K cb values after adjustment to the standard climate adopted in FAO56, where average RH min = 45% and average u 2 = 2 m s −1 over the mid-season and late season growth stages. For each vegetable crop, these standard values were then compared with the FAO56 tabulated K c and K cb values to define the updated values tabulated in the current article. In addition, reported ancillary data, such as maximum root zone depth, maximum crop height, and soil water depletion fraction for no water stress, were also collected from selected papers and tabulated in comparison with those given for the crops in FAO56. The presentation of updated crop coefficient results is performed by grouping the vegetables differently than in FAO56, where distinction is made according to their edible parts:(1) roots, tubers, bulbs and stem vegetables; (2) leaves and flowers vegetables; (3) fruit and pod vegetables; and (4) herbs, spices and special crops, with most of them being newly introduced herein. The updated K c and K cb of veget...

This study reviews the abundant research on FAO56 crop coefficients, published following introduction of the FAO56 paper in 1998. The primary goal was to evaluate, update, and consolidate the mid-season and end-season single (K c ) and basal (K cb ) crop coefficients, tabulated for many field crops in FAO56. The review found that the prevalent approach for estimating crop evapotranspiration (ET c ) is the FAO56 K c -ET o approach, i.e., the product of the K c and reference evapotranspiration (ET o ). The FAO56 K c -ET o approach requires use of the FAO56 PM-ET o grass reference equation with appropriate crop-specific K c and/or K cb . Reviewed research provided various approaches to determine K c and K cb and used a variety of actual crop ET (ET c act ) measurements. Significant attention was placed on accessing the accuracy of the field measurements and models used in these studies. Accuracy requirements, upper limits for K c values, and related causal errors are discussed. Conceptual approaches relative to K c transferability requirements are provided with focus on standard crop conditions and use of the FAO56 segmented K c curve. Papers selected to update K c ∕K cb used the FAO56 PM-ET o , provided accurate measurements to determine and partition ET c act , and satisfied transferability requirements. Selected observed K c and K cb values were converted to standard, sub-humid climate as adopted in FAO56. Observed values, with respect to tabulated FAO56 K c and K cb , were used in consolidating updated values for crops within general categories of grain legumes, fiber crops, oil crops, sugar crops, small grain cereals, maize and sorghum, and rice. Ancillary data, e.g., maximum root depth and crop height, were also collected from selected literature and tabulated. Results showed good agreement between updated and original tabulated FAO56 K c and K cb , confirming the reliability of the FAO56 values. This indicates change in the K c (ET c /ET o ratio) of crops has not occurred due to climate change during the past ≈sixty years. New K c ∕K cb data for crops, not included in FAO56, are also now presented for several oil crops and pseudocereals. The approach adopted for rice differs from FAO56 because consideration was given to the numerous rice water management practices currently used and, thus, K c ∕K cb values for the initial season of rice were also presented. The review also observed that many research papers did not satisfy the adopted requirements in terms of ET o method and/or the accuracy of ET c act determinations and, therefore, could not be used. Thus, emphasis is placed on adopting improved accuracy and quality control in future research aimed at determining K c data comparable to presented values. The transferability of standard K c and K cb has been assured for the values tabulated herein. Improved future applications of the FAO56 K c -ET o method should consider remote sensing observations when available, particularly in defining crop growth stages at given locations.

This study investigated the effects of broadband and selected infrared (IR) wavelength treatments of rough rice on microbial inactivation. Rough rice was treated at different IR wavelengths and product‐to‐emitter distances (110, 275, and 440 mm) followed by tempering at 60°C for 4 hr. The total mold and aerobic plate counts (APC) on non‐treated and treated samples were determined. Significant total mold reductions of 1.14 and 3.11 log CFU/g were obtained after IR heating using broadband and selected wavelengths, respectively (p < .05). The most significant reduction of APC using selected IR wavelength was 1.09 log CFU/g; the broadband IR wavelength had no effect on the mean APC. The IR treatments followed by tempering step resulted in greater reductions of total mold counts and APC (4.03 and 3.50 log CFU/g) in comparison to IR treatments without tempering (3.11 and 1.09 log CFU/g). Overall, bacteria showed more resistance to IR treatments than molds.

Mycotoxigenic fungal contamination of corn poses significant health-related risks to consumers (Shad and Atungulu, 2017; Atungulu et al., 2018). The most prevalent mycotoxins that contaminate corn in the United States include aflatoxins, fumonisins, and deoxynivalenol (Abbas et al., 2002; Mohammadi Shad et al., 2019b; Robens & Cardwell, 2003; Wu et al., 2011). Chauhan et al. (2016) conducted a study on fungal infection, and aflatoxin contamination in corn collected from the Gedeo zone in Ethiopia and found that Aspergillus (75%), Fusarium (11%), Penicillium (8%), and Trichoderma (6%) were the predominant genera of fungi that contaminated the corn grains. Aflatoxins (produced by Aspergillus), deoxynivalenol, and fumonisins (produced by Fusarium) were also found in locally grown corn in 18 African nations during 2007 and 2008 (Probst et al., 2014). Lane et al. (2018) also found that Fusarium was the most abundant genus after exploring the fungal microbiome of corn during hermetic storage in the United States and Kenya.

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Background The popularity of grain‐based ethanol production, especially via dry‐grind bioethanol from corn and subsequent accumulation of low‐value coproducts, especially dried distillers grain with solubles (DDGS), has emphasized the need to add value to the process by recovering different corn components for potential food, feed, and industrial applications prior to ethanol fermentation. Findings Modification in corn processing, including the fractionation process, has manifested in variation in product yield such as ethanol. However, the value‐added products thus obtained boost their quality, potentially increasing the profitability of dry‐grind corn ethanol process. Corn oil, being the most valuable corn component, presents itself as an attractive candidate for front‐end and tail‐end separation of germs. Although the corn oil does not take part in starch fermentation into ethanol, the implication of the front‐end degermination in dry‐grind corn process on downstream product recovery is an essential consideration in bioethanol yield. Process improvement has taken a further step to increase the ethanol yield and rate by processing alpha‐amylase corn, providing critical nutrients and superior yeast. Conclusions Corn ethanol production, quality of coproducts, germ separation, and oil recovery have been enhanced with component recovery either before or after fermentation. However, the economic aspects of the corn bioprocessing advancements need to be further evaluated for commercial implications. Significance and novelty This review summarizes the current knowledge about the significant corn processing methods. It critically reviews germ fractionation, its role in the processing parameters, and the potential for increased value‐added products such as corn oil.

Background and objectives: Rice kernel discoloration during storage results in significant economic losses to rice growers and processors. This study aimed to elucidate the extent of chemical changes and microbial involvement on discoloration of rice kernels during storage. To segregate and/or diminish the effects of microbes, one lot of hybrid long-grain rice (XL753) samples was irradiated with nonthermal electron beam (EB) dose of 14 kGy. The irradiated and nonirradiated control samples of rice at a moisture content (MC) of 21% on a wet basis were stored at three temperatures (20, 30, and 40°C) for 8 weeks. Samples were taken every 2 weeks for microbial and chemical analyses. Findings: A negative relationship was noted between discoloration and microbial load. The trend of increasing discoloration and chemical properties such as free sugars, free fatty acid, and free 5-hydroxymethyl-2-furaldehyde (HMF), especially at higher storage temperatures and durations, suggested that biochemical changes were major drivers of the observed rice discoloration. The higher HMF in highly discolored rice (≥20%) explained nonenzymatic browning in the rice matrix during storage. Conclusions: From this study, it was drawn that the rice kernel discoloration was not directly related to the microbial load; the discoloration was seen in EBI rice even with 99% reduction in microbial load. However, it was clarified that the rice discoloration especially in EBI rice samples was related to the observed chemical changes, which were also storage temperature dependent. Significance and novelty: Milled rice discoloration during storage of rough rice is insufficiently understood. There is no information correlating changes in chemical attributes and microbial activity to discoloration of contemporary hybrid rice during storage. Therefore, the results of the current study provide important fundamental information and also suggest storage conditions required to arrest discoloration and maintain quality of contemporary milled hybrid rice. K E Y W O R D Schemical changes, microbes, postharvest treatments, rice kernel discoloration, storage | 825 MOHAMMADI SHAD et Al.

Abstract. The level of aflatoxin B1 (AFB1) in dairy cow feed ingredients and Total Mixed Rations (TMRs) procured at two farms for low- and high-yielding dairy cows were surveyed. Raw milk from the two groups of cows at each farm was sampled 24 h after feeding the cows with examined feedstuffs during both the rainy and the non-rainy season. The aflatoxin M1 (AFM1) level in the raw milk samples was measured 12-24 h later. The levels of AFB1 in feed and AFM1 in milk were determined by validated enzyme linked immunosorbent assay (ELISA). The influence of farm management and type of feeding system on aflatoxin occurrence were considered. AFB1 and AFM1 were detected in 100% of feed and milk samples, respectively. The average level of AFB1 in the feed ingredients and TMRs were in the range of 1.6-104.7 µg/kg and 11.0-56.0 µg/kg, respectively. The average level of AFM1 in milk samples was 77.0 ng/L. The average concentrations of AFB1 in feeds and AFM1 in milk procured in the rainy season were significantly greater than those procured in the non-rainy season (p&lt;0.05). Of the studied feed, maize silage was determined as the most contaminated feed ingredient in terms of AFB1 content. Furthermore, the AFM1 in 75% of milk samples obtained from high-yielding dairy cows and 25% of milk samples obtained from low-yielding dairy cows indicated AFM1 level higher than the maximum allowable Europe Commission limit of 50 ng/L. The results also showed that the occurrence of AFB1 in feed varied with farm feed management. The extent of translocation to AFMI in milk samples was dependent on type of cow, whether low- or high- milk yielding. This study suggests regular risk analysis and using good farm management practices are important to control aflatoxin contamination in feed and milk. Keywords: Aflatoxin B1, Aflatoxin M1, Dairy cows, Feed, Milk yield.