Reducing Transfer of Salmonella and Aerobic Mesophilic Bacteria on Melon Rinds Surfaces to Fresh Juice by Washing With Chlorine: Effect of Waiting Period Before Refrigeration of Prepared Juice

Cantaloupes, honeydew melons and watermelons inoculated with Salmonella cocktail at 4.5, 3.8, and 3.2 log10 CFU/cm2, respectively, were sanitized with 200 ppm chlorine before rinds removal, cutting, and juice preparation. Efficacy of 200 ppm chlorine in reducing transfer of Salmonella, aerobic mesophilic bacteria, yeast and mold, and Pseudomonas from the melon surfaces to freshly prepared fruit juice was investigated including the effect of waiting period before refrigeration of the juices. The melon juice filtrates were refrigerated immediately or stored at room temperature (~22°C) for 3 and 5 h before refrigeration. Average Salmonella bacteria recovered in fresh melon juice prepared from unwashed whole cantaloupes, watermelon and honeydew melons was 1.4, 0.5, and 0.4 log10 CFU/ml, respectively. Juices from unwashed inoculated melons had the highest bacterial populations and storage at an abusive temperature of 10°C led to proliferation. Holding these juices at room temperature for 5 h before refrigeration allowed Salmonella bacteria to increase by 0.5–0.8 log in cantaloupe juice and 0.3–0.5 log in watermelon and honeydew juices. No Salmonella bacteria was determined in fresh juices prepared from melons washed with chlorinated water. The results of this study showed that washing melons with 200 ppm chlorine before juice preparation and immediately refrigerating the juice will minimize the chances of Salmonella proliferation

Molecular Level Comparison of Water Extractives of Maple and Oak with Negative and Positive Ion ESI FT-ICR Mass Spectrometry

Soluble extractives in wood function to protect living trees from destructive agents and also contribute to wood color and fragrance. Some extractive components have biological activities with medical applications. They also play important roles in wood processing and related applications. To increase the knowledge of wood chemistry, maple and oak were extracted by water. Ultraviolet/visible (UV/vis) spectroscopy indicated the presence of a phenolic compound, resorcinol, in maple extractives having higher molecular mass and more aromatic components than oak extractives. Negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS) identified thousands of formulas in the two samples in the m/z range of 200 to 800. They mainly fall into the lignin-like, carbohydrate-like, and tannin-like compound categories. The top 25 peaks (ie, formulas) with the highest relative magnitude in negative ESI represented nearly 50% of the summed total spectral magnitude of all formulas assigned in the maple and oak extractives. Furthermore, the base peak (ie, most abundant peak) accounted for about 14% of the total abundance in each wood sample. Literature comparisons identified 17 of 20 formulas in the top five peaks of the four spectra as specific bioactive compounds in trees and other plants, implying the potential to explore utilization of maple and oak extractives for functional and medicinal applications. The various profiling of the top 25 peaks from the two samples also suggested the possible application of FT-ICR-MS for detecting chemical markers useful in profiling and identification of wood types and sources

Effects of Particle Size on the Morphology and Water- and Thermo-Resistance of Washed Cottonseed Meal-Based Wood Adhesives

Water washing of cottonseed meal is more cost-efficient and environmentally friendly than protein isolation by means of alkaline extraction and acidic precipitation. Thus, water-washed cottonseed meal (WCSM) is more promising as biobased wood adhesives. In this work, we examined the effects of the particle size on the morphology and adhesive performance of WCSM. Pilot-scale produced and dried WCSM was treated by three grinding methods: (1) ground by a hammer mill and passed through a 0.5-mm screen, (2) further ground by a cyclone mill and passed through a 0.5-mm screen, or (3) further ground by a ball mill and passed through a 0.18-mm screen. Micro-morphological examination revealed two types of particles. The filament-like particles were mainly fibrous materials from residual linters. Chunk-like particles were more like aggregates or accumulations of small particles, with proteins as the major component. Further grinding of the 0.5-mm Hammer product with the Cyclone and Ball mill led to more fine (smaller) particles in the WCSM products. The impact of further grinding on the dry and soaked adhesive strengths was minimal. However, the decrease of the hot and wet strengths of WCSM products by the additional grinding was significant (p ≤ 0.05). Data presented in this work is useful in developing the industrial standards of WCSM products used in wood bonding

Potato Growth and Yield Characteristics under Different Cropping System Management Strategies in Northeastern U.S.

Cropping systems and management practices that improve soil health may greatly enhance crop productivity. Four different potato cropping systems designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo (SQ) standard rotation, along with a non-rotation (PP) control, were evaluated for their effects on potato crop growth, nutrient, and yield characteristics under both irrigated and non-irrigated (rainfed) conditions in field trials in Maine, USA, from 2004 to 2010. Both cropping system and irrigation significantly (p < 0.05) affected most potato crop parameters associated with growth and yield. All rotations increased tuber yield relative to the non-rotation PP control, and the SI system, which included yearly compost amendments, resulted in overall higher yields and a higher percentage of large-size tubers than all other systems with no irrigation (increases of 14 to 90%). DS, which contained disease-suppressive green manures and cover crops, produced the highest yields overall under irrigation (increases of 11 to 35%). Irrigation increased tuber yields in all cropping systems except SI (average increase of 27–37%). SI also resulted in significant increases in leaf area duration and chlorophyll content (as indicators of photosynthetic potential) and root and shoot biomass relative to other cropping systems, particularly under non-irrigated conditions. SI also resulted in higher shoot and tuber tissue concentrations of N, P, and K, but not most micronutrients. Overall, cropping systems that incorporate management practices such as increased rotation length and the use of cover crops, green manures, reduced tillage, and particularly, organic amendments, can substantially improve potato crop growth and yield. Irrigation also substantially increased growth and yield under normal field conditions in Maine, but SI, with its large organic amendments, was essentially a substitute for irrigation, producing comparable results without irrigation

Potato Growth and Yield Characteristics under Different Cropping System Management Strategies in Northeastern U.S.

Cropping systems and management practices that improve soil health may greatly enhance crop productivity. Four different potato cropping systems designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo (SQ) standard rotation, along with a non-rotation (PP) control, were evaluated for their effects on potato crop growth, nutrient, and yield characteristics under both irrigated and non-irrigated (rainfed) conditions in field trials in Maine, USA, from 2004 to 2010. Both cropping system and irrigation significantly (p < 0.05) affected most potato crop parameters associated with growth and yield. All rotations increased tuber yield relative to the non-rotation PP control, and the SI system, which included yearly compost amendments, resulted in overall higher yields and a higher percentage of large-size tubers than all other systems with no irrigation (increases of 14 to 90%). DS, which contained disease-suppressive green manures and cover crops, produced the highest yields overall under irrigation (increases of 11 to 35%). Irrigation increased tuber yields in all cropping systems except SI (average increase of 27–37%). SI also resulted in significant increases in leaf area duration and chlorophyll content (as indicators of photosynthetic potential) and root and shoot biomass relative to other cropping systems, particularly under non-irrigated conditions. SI also resulted in higher shoot and tuber tissue concentrations of N, P, and K, but not most micronutrients. Overall, cropping systems that incorporate management practices such as increased rotation length and the use of cover crops, green manures, reduced tillage, and particularly, organic amendments, can substantially improve potato crop growth and yield. Irrigation also substantially increased growth and yield under normal field conditions in Maine, but SI, with its large organic amendments, was essentially a substitute for irrigation, producing comparable results without irrigation