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Anthocyanidins, prepared by the acid hydrolysis of black bean and blackberry anthocyanins, were deposited in C18 solid-phase extraction (SPE) cartridges from four different manufacturers. The amoun...

The effects of composition, temperature, and storage time on the textural attributes of a starch–sucrose gel system were determined by means of textural profile analysis (TPA) tests. Mixtures of high amylose corn starch, sucrose, and water were jet cooked at temperatures of 110–150 °C, rapidly cooled to gels on a refrigerated belt, and stored at 1 °C. Treatment temperature, storage time, sucrose/starch ratio and water added/solids ratio were used as independent variables. The ranges of sucrose, starch, and water added were 0–14.9, 14.4–33.6, and 48.3–77.8 g/kg, respectively. All four independent variables were found to be significant in second order response surface equations, describing all textural attributes but adhesiveness. Hardness, fracturability, gumminess, and chewiness were exponentially related to quadratic functions of the variables while resilience, cohesiveness, and springiness were linearly related. Adhesiveness values were low and independent of the variables. In general, values of textural attributes increased with temperature and storage time, and were inversely related to sucrose/starch ratio and water added/solids ratio.

A series of unsaturated branched esters were purified by preparative gas chromatography and their odor thresholds were determined using sensory panel methods. In general, unsaturated branched esters had higher odor thresholds than their saturated counterparts. Double bond position and configuration had marked influences on the odor threshold. In most cases, the addition of a double bond in the C-2 position of the acid resulted in significantly higher odor thresholds while the addition of a double bond in positions further away from the acid carbonyl had a smaller effect on the odor threshold. Ethyl 2-methyl-4-pentenoate had the lowest odor threshold (0.01 μL/10 3 L) of the esters tested while methyl (E)-2-methyl-2-butenoate (methyl tiglate; 130 μL/10 3 L) had the highest odor threshold.

Three anthocyanins were isolated from the acidified methanol extracts of UI 911 black beans (Phaseolus vulgaris L.) using solid phase extraction and preparative high-performance liquid chromatography . The anthocyanins were characterized using chromatographic and spectroscopic methods as delphinidin 3-glucoside (56%), petunidin 3-glucoside (26%), and malvidin 3-glucoside (18%). The monomeric anthocyanin content was 213 ± 2 mg/100 g of black beans (moisture content was 10.04 ± 0.02%). Keywords: Black beans; antioxidants; pigments; anthocyanins; electrospray ionization mass spectrometry

Dry small white beans (Phaseolus vulgaris) were ground and processed through a twin-screw extruder using three screw configurations of increasing energy intensity. Products were made over a moisture range of 150-250 g/kg, and barrel temperatures of 56-184°C. Results were examined by means of response surface methodology. Extrudate properties were significantly dependent (P < 0.10) on both the screw configuration and extrusion conditions used. In general, as the energy intensity of the configuration increased, expansion ratio, starting viscosity and hot viscosity increased, while bulk density, ending viscosity, and trypsin inhibitor activity decreased. All properties could be mathematically described as a function of the feed moisture content, the die temperature, and the specific mechanical energy consumption (SME) in Wh/kg, as determined on an 'as is' basis. R2 and overall P values ranged from 0.708-0.999 and 0.001-0.40, respectively. Residual trypsin inhibitor activity in the extruded products was low (

Fresh pimento pulp waste was dehydrated in a pilot Arnold dehydrator to give meals rich in the red xanthophylls, primarily capsanthin. Xanthophyll content of the dehydrated meal ranged from 896 to 1114 mg/kg. Dejuicing of the pimento pulp prior to dehydration decreased charring during drying as well as the quantity of water to be evaporated. Carotenoid losses during dehydration ranged from 17 to 22% for xanthophyll and 0 to 10% for carotene. Although the unprotected pimento carotenoids were rapidly lost during storage either alone or in admixture with dehydrated lucerne, addition of the antioxidant ethoxyquin proved to be very effective in preventing carotenoid storage losses. Levels of 1% pimento meal should be adequate in poultry diets when fed in combination with lucerne meal.

A pilot-scale process for preparing high-protein, low fiber (

Using broiler chicks, the nitrogen corrected metabolizable energy (ME) was determined for wheat bran, pelleted wheat bran, and three pelleted wheat brans to which either NaOH, NH4OH, or HCl were added prior to pelleting, and wheat bran treated with a commercial cellulolytic enzyme concentrate (Pectinol 41P). The dry matter ME values were 1612, 1659, 1645, 1703, 1770, and 2132 kcal/kg, respectively. The ME values for the HCl-pelleted bran and Pectinol 41P-treated bran were both significantly higher than that of the untreated bran and significantly different from each other (P=.05). There was no significant improvement in ME from the other bran treatments. The ME was also determined for three wet alkaline processed wheat millrun protein concentrates containing oh a dry matter basis 27, 27, and 24% protein, .9, 1.0, and 1.1% crude fiber, and 47, 51, and 49% starch, respectively. The millrun concentrates were found to contain 3803, 3882, and 3770 kcal ME/kg, respectively. The average ME value of the millrun concentrates was about 96% higher than the ME of the original wheat millrun.

Pilot scale ultrafilter units were tested for use in concentrating and Purifying soluble alfalfa leaf protein solutions. Tubular and hollow fiber type units with noncellulosic membranes were employed. Operating temperature was generally maintained at 10° C because of microbial growth and precipitation of the heat labile protein at higher temperatures. Higher permeation rates and lower protein losses were obtained with the tubular unit. Concentrating the clarified alfalfa juice to 1/10 of the original volume produced protein concentrates containing about 50% crude protein and 10% ash. Diafiltration of the clarified alfalfa juice until the permeate volume was 10 times the original sample volume resulted in products containing 70–76% protein. Although diafiltration removed more than 86% of the orthodihydroxy phenolic compounds, the dried protein products were tan colored.

A prototype leaf stripping machine and a conventional forage harvester with a raised header were used to obtain high protein lucerne (alfalfa) fractions. The stripped lucerne leaves and lucerne tops contained 26.2 and 27.2% protein, respectively. Pilot-scale extraction of the ground leaves and the ground tops resulted in leaf protein concentrate (LPC) yields of 18.8 and 20.0%, respectively, compared with 12.8 and 15.7% for the appropriate whole lucerne control. LPC yields as high as 27.4% were obtained by the addition of lucerne solubles to the lucerne tops prior to grinding. Low LPC yields (4.0–8.0%) were obtained from the lucerne stem fraction. After processing, the press cake fraction from the leaf-enriched feed materials still contained over 17% protein.

ADSTRACTA twin screw press was used to dewater ground alfalfa feed material. The dewatering behavior of the ground alfalfa and the yield of leaf protein concentrate (LPC) were determined. Grinding signifi-cantly increased the extraction of juice, solids, and nitrogen from the feed alfalfa, the dry matter content of the resultant press cake, and the yield of LPC. The average yield of LPC was 15.2 percent of the ground alfalfa feed weight (dry basis), an increase of 62 percent compared to a chopped unground alfalfa control. The yield of LPC and other processing results were approximated by appropriate multiple linear equations. The yield of LPC was dependent on the temperature, dry matter, fiber and protein contents of the feed alfalfa. The yield of juice was dependent on the feed alfalfa fiber and dry matter contents.

Leaf protein concentrate (Pro-Xan) production requires cell maceration for protein release. Alfalfa cell rupture was studied with a commercial scale vertical hammer mill with respect to feed rate, hammer-wall clearance, type and number of hammers, agitation rate, energy input, and juice recycle. Degree of cell rupture was measured by comparing the amount of true protein nitrogen liberated by cell maceration to that present in the raw material. Degree of cell rupture, degree of cell rupture per unit of energy input, and mass of protein released were optimized independently with respect to operating parameters by the linear programming technique known as the Simplex method.

The leafy tops of kenaf plants grown as a paper pulp crop were analysed to assess their potential value as a feedstuff. Procedures were investigated for incorporating ammonia nitrogen into the material to enhance its nutritive value. Nitrogen thus fixed was stable during subsequent hot-air drying of the product.