R. G. Koegel

LEACHATE CONDUCTIVITY AS AN INDEX FOR QUANTIFYING LEVEL OF FORAGE CONDITIONING

A method based upon measuring the conductivity of the leachate (LC) from mechanically conditioned forage was evaluated and used as an index for quantifying the extent of mechanical damage caused by various mechanical treatments. Relative to a Surface Area Index (SAI) method previously used, the LC method was simple, fast, and could be completed with readily available laboratory equipment (orbital shaker table, Waring® blender, and conductivity meter). The LC method differentiated various mechanical conditioning treatments more often and with greater sensitivity than the SAI method. The consistency of different Waring blender treatments was assessed to determine if it could be used as a standard treatment for normalizing leachate conductivity values.

Evaluating Longitudinal Shear as a Forage Maceration Technique

ABSTRACT ALFALFA can be dried rapidly if it is macerated and formed into a mat. Maceration must severely condition the plant for rapid drying and still maintain fiber length to insure mat strength. A maceration method which produces these physical qualities involves repeated shearing of the plant stem along its length. The effects of stem segment, plant maturity and harvest on the longitudinal shear properties of alfalfa were studied. Results indicate that longitudinal shear of alfalfa stems requires less than 1/10 the reported energy to shear alfalfa transversely. Therefore, energy requirements for maceration should be comparable with those of other alfalfa processes.

Physical Parameters of Macerated Alfalfa Related to Wet Strength of Forage Mats

ABSTRACT IN order to utilize the fast-drying properties of macerated forage mats, adequate wet mat strength must be produced to allow placing them intact on the forage stubble. Mat strength and drying rate are dependent upon, among other formation factors, adequate maceration. Methods were developed to determine physical parameters of macerated alfalfa, including specific surface area, quantity of long fibers, short particle length and material compliancy. The quantified physical parameters were then related to mat strength. Results indicate that wet mat strength decreases with the severity of the maceration. A surface area index, based on rate of water absorption, was found to be a good measure of severity of maceration, and can be used to predict mat properties and the other physical parameters measured.

Evaluation of a crushing-impact forage macerator

An experimental forage maceration device, consisting of a flail mower, two crushing rolls, and an impact rotor was fabricated and evaluated. Force applied to the crushing rolls flattened the tubular structure of the plant stem creating longitudinal cracks, thereby making the plant fiber more compliant and ribbon-like. Maceration occurred as the crushed plant material was struck by a finned rotor. Several factors were critical for producing well-macerated forage including impact rotor speed, specific crushing roll force, and feed rate into the crushing rolls. The specific energy required by the crushing-impact macerating unit, not including the flail mower, ranged from 0.56 to 2.28 kW.h/t. However, under typical feed rates, the impact macerator effectively processed third crop alfalfa at specific energy requirements from 0.56 to 1.01 kW.h/t.

Drum Drying of Plant Juice Protein Concentrates

ABSTRACT PLANT juice protein concentrates can be success-fully dried using a drum or roller dryer. Roll temperature, roll speed, and nip clearance affect performance. Drum temperatures of 110 °C to 130 °C are practical. Final moisture content is dependent on the drum speed at any given temperature. Throughput rates of 3.3 to 6.4 kg/m2 h are possible. Efficiency of the drum dryer is acceptable. Protein quality can be maintained.

Forage Harvester Orientation Mechanism to Reduce Particle Size Variation

A third set of feed rolls, one of which contains a cam-actuated combing mechanism, was placed between the normal feed rolls and the cutterhead of an experimental forage harvester. This mechanism was intended to orientate stems of forage, such as alfalfa, before being commutated by the cutterhead and thereby reduce particle size variation. When the 1:1 combing ratio was used as a control, the combing mechanism reduced the percent longs, shortened the geometric mean length, and lowered the geometric standard deviation of the particle size distribution. Increasing the combing ratio was beneficial up to the limit of 3:1. The percent longs were reduced by up to 48%, the geometric mean length was reduced by up to 29%, and the geometric standard deviation was reduced by up to 15% with a combing ratio of 3:1. However, the control forage harvesters consistently produced chopped material with fewer percent longs, shorter geometric mean length, and lower geometric standard deviation than the experimental machine. This may have been at least partially due to non-uniform feeding from the pick-up of the experimental machine. Net specific energy requirements of the combing mechanism and clean-off roll were less than 0.24 kWh/t.

Design Criteria for a Forage Plant Fractionation Press

ABSTRACT This paper relates the fractionation characteristics of macerated forage to the size and speed re-quirements for the fractionation press. The paper discusses the cone press as the configuration believed to be most suitable for dejuicing forages. An analysis of this configuration is performed to relate the physical dimen-sions of the press to the compression ratio, expected throughput, and coefficient of friction required to pre-vent slippage between the forage material and the confin-ing surfaces. Specifications for the compression ratio and energy requirements are then made based on an empir-ical study of the fractionation properties of macerated alfalfa compressed at various fixed rates of volume reduction.

Radial blade and anvil forage cutterhead.

ABSTRACT The specific energy and maximum force required to shear alfalfa stems with a knife and anvil mechanism were determined in a universal testing machine. Subsequently a small rotary cutterhead based on the same type of cutting was evaluated. Specific energy requirement and mean length of cut compared favorably with conventional cutterheads.

Heating Effects on Plant Juice Protein Recovery

ABSTRACT THE effect of post harvest heating on the recovery of and composition of alfalfa juice protein was evaluated. All materials were evaluated using a flotation system, a belt filtration system, and a combination belt-flotation system. Heating of the alfalfa resulted in deterioration of the crop material for juice protein pro-duction. Extractable solids in the juice decreased, pro-tein recovery decreased, and protein moisture increased. Nitrogen distribution in the recovered protein was also altered.