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During rough rice drying, gradients of moisture content and glass transition temperature cause thermal and mechanical stresses inside the kernel. These stresses eventuate to kernel fissuring during the milling process. In this study, convective drying of Hashemi (long grain) rough rice was applied to investigate the effect of continuous and stepwise changes in air temperature on stress cracking index and process duration. Toward this objective, the concepts of glass transition and analysis of moisture contents distributions within the rice kernel were determined through a numerical modeling of mass transfer. For stepwise temperature change, the drying experiments were conducted at temperatures above the glass transition temperature. Results indicated that the stress cracking index under stepwise temperature change conditions (i.e., within the rubbery state) was reduced compared to the continuous mode probably due to a drip in the moisture content gradients created inside the kernels during the drying process. Moreover, the drying duration significantly was shortened when the kernel was dried within the rubbery state due to faster diffusion moisture within the kernel. [ABSTRACT FROM AUTHOR]

Reliable prediction of the risk of mycotoxin contamination in post-harvest wheat will aid in improvement of the quality and safety. To establish the relationship between Fusarium pseudograminearum mycotoxins and CO 2 production, changes in their respective concentrations were monitored for the artificial contamination of wheat under different values of water activities (0.84 a w , 0.92 a w , and 0.97 a w ) and temperatures (20 ℃, 25 ℃, and 30 ℃). Water activity played a significant role in all these processes. CO 2 concentration together with moisture content and temperature were used as the main parameters to establish DON and ZEN contamination prediction models. The prediction accuracy for DON was 98.15 % (R 2  = 0.990) and 90.74 % for ZEN (R 2  = 0.982). These models were combined with T/RH/MC/CO 2 multi-parameter integrated sensors to form an early warning system, which offers a great prospect to minimise the risk of DON/ZEN contamination in post-harvest wheat., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Heat stress during the grain-filling period is the main abiotic stress factor limiting grain yield and quality in wheat ( Triticum aestivum L.). In this study, 64 wheat genotypes were exposed to heat stress during reproduction caused by delayed sowing in two growing seasons. Grain yield, 1000 grain weight (GW), grain hardness (GH), and grain-quality related traits were investigated. Heat stress caused a significant decrease in GW through reducing starch content (SC) and a non-compensating rise in protein content (PC), and thereby resulted in lower yield. In addition, significant increases in flour water absorption (WA), Zeleny sedimentation volume (ZT), ash content (AC), lipid content (LC), loaf volume (LV), wet gluten content (WG), dry gluten content (DG), gluten index (GI), and amylopectin content (APC) were found following heat stress. In contrast, decreases in grain moisture content (MC) and amylose content (AMC) induced by heat stress were observed. The heat-tolerant genotypes were superior in grain yield, GW, SC, AMC, and MC. While the sensitive genotypes contained higher PC, LV, GI and AMP. A group of wheat genotypes characterized with a higher yield, AMC, GW, and SC as well as lower PC, WA, GH, ZT, and LV; and was found to be the most heat tolerant by principal component analysis. Lighter weight and smaller grains produce a smaller starchy endosperm with lower quality (less amylose) and higher grain protein content in heat stress compared to normal conditions. Heat stress caused by delayed sowing improves some of the baking-quality related traits., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Compost was tested as a medium for organic container-grown crops. Nitrogen (N) loss during composting of separated cow manure (SCM) was minimized using high C/N (wheat straw, WS; grape marc, GM) or a slightly acidic (orange peels, OP) additives. N conservation values in the resultant composts were 82%, 95% and 98% for GM-SCM, OP-SCM and WS-SCM, respectively. Physical characteristics of the composts were compatible with use as growing media. The nutritional contribution of the composts was assessed using cherry tomato (Lycopersicon esculantum Mill.) and by means of incubation experiments. Media were either unfertilized or fertilized with guano (sea-bird manure). Plant responses suggest that N availability is the main variable affecting growth. Unfertilized OP-SCM and WS-SCM supplied the N needed for at least 4 months of plant growth. Root-galling index (GI) of tomato roots and number of eggs of the nematode Meloidogyne javanica were reduced by the composts, with the highest reduction obtained by OP-SCM and WS-SCM, at 50% concentrations. These composts, but not peat, reduced the incidence of crown and root-rot disease in tomato as well as the population size of the causal pathogen, Fusarium oxysporum f. sp. radicis-lycopersici. [Copyright &y& Elsevier]

Abstract: Chemical inactivation of aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) in maize grain by means of 1N aqueous citric acid was confirmed by the AFLATEST™ immunoaffinity column method, high performance liquid chromatography (HPLC), and the Ames test (Salmonella-microsomal screening system). The AFLATEST™ assay showed that aflatoxins in the maize grain with an initial concentration of 29ng/g were completely degraded and 96.7% degradation occurred in maize contaminated with 93ng/g when treated with the aqueous citric acid. Aflatoxin fluorescence strength of acidified samples was much weaker than untreated samples as observed in HPLC chromatograms. On the other hand, the Ames test results indicated that the mutagenic activity of acidified samples was greatly reduced compared with that of untreated samples based on his−→his+ reversions in the Salmonella TA100 strain. Chemical inactivation appears to be a promising method of removing aflatoxin from food commodities. [Copyright &y& Elsevier]

The objective of this research is to evaluate drying methods that have the potential of adding value to green asparagus especially for use as ingredient in instant foods or as a nutraceutical product. Five drying methods were used: namely, tray drying (TD), spouted bed (SB) drying, combined microwave and spouted bed drying (MWSB), Refractance Window (RW) drying and freeze-drying. Asparagus spears with diameters between 9 and 12 mm were blanched in 85°C water-bath for 3 min, sliced into 2–4 mm thickness (or pureed for RW drying), then dried to moisture content less than 0.1 db. MWSB drying produced asparagus particles with good rehydration and color characteristics, and was the fastest among the methods where heated air was used. When using MWSB drying, the power level of 2 W/g and 60°C heated air resulted in highest retention of total antioxidant activity (TAA). TAA of asparagus was enhanced after RW and freeze-drying, with the TAA values being significantly higher than for heated air-drying methods. In all cases, the tip portion of asparagus retained more TAA after drying than either middle or basal parts. The highest amount of ascorbic acid was retained in the product after RW drying, followed by freeze-drying, MWSB and SB drying. TD resulted in the least retention of ascorbic acid. [Copyright &y& Elsevier]