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Eight treatment combinations for the formulation and heating of fresh ground pork were investigated: four raw fat levels (4, 9, 18, 23%) and two internal end point temperatures (71° and 77°C). In the raw state, ground pork containing 4 or 9% fat contained less cholesterol, more moisture and was judged to be more red than samples containing 18 or 23% fat. Tenderness, juiciness and amount of mouthcoating in­ creased as fat level in the cooked patties increased. Internal end point temperature (71° or 77°C) did not affect sensory scores of cooked pork patties. Cooked patty cholesterol content (wet weight) did not differ among the four fat levels. High-fat ground pork re­ tained less cholesterol than low-fat ground pork.

BACKGROUND: It is well known that the foaming properties of egg white protein are significantly reduced when a small amount of yolk is mixed in the white. To improve foaming properties of yolk-contaminated egg white protein, soy protein isolate (SPI) and egg proteins were modified to make basic proteins, and effects of these modified proteins on egg white foaming were evaluated in a model and an angel cake system. RESULTS: SPI and egg yolk proteins were modified to have an isoelectric point of 10, and sonication was used to increase protein dispersibility after the ethyl esterification reaction. However, only the addition of sonicated and modified SPI (SMSPI) showed improvement of foaming in the 5% egg protein model system with 0.4% yolk addition. SMSPI was then used in making angel food cake to examine whether the cake performance reduction due to yolk contamination of the white would be restored by such alkaline protein. Cake performance was improved when cream of tartar was used together with SMSPI. CONCLUSION: Basic soy protein can be made and used to improve egg white foaming properties and cake performance. Copyright © 2012 Society of Chemical Industry

Soymilk made from lipoxygenase-free soybeans had less cooked beany aroma, less cooked beany flavor and less astringency and was rated darker and more yellow than that made from soybeans with normal lipoxygenase. Sensory descriptive panelists noted no differences between lipoxygenase-free and normal soybeans for milky flavor, wheat flavor, thickness, chalkiness or aftertaste. Tofu made from lipoxygenase-free soybeans had less cooked beany flavor than that made from normal soybeans. There were no differences in cooked beany aroma, raw beany aroma, raw beany flavor, wheat flavor, astringency, hardness, darkness or yellowness. Native-born Japanese, Chinese and U.S. descriptive panelists differed in responses to flavor, texture and color of soymilk and tofu.

Consumer preference and acceptance sensory tests and volatile flavor analyses of apple cider (irradiated and pasteurized with potassium sorbate) were conducted in 2001 (599 panelists) and 2002 (577 panelists). In 2001, irradiated cider was preferred at 2 locations, whereas at the other 2 locations, neither sample was preferred. In 2002, the acceptability rating was 6.24 for irradiated cider and 6.41 for pasteurized cider, rating on a 7-point hedonic scale (1 = dislike very much; 7 = like very much). Acceptability of the pasteurized cider was significantly higher at 1 location. In both years, ciders with higher levels of esters and other compounds typical of apple flavor had higher preference and acceptability ratings.

Papayas, rambutans, and Kau oranges were irradiated at 0 (control) and 0.75 (irradiated) kGy and stored for 2 and 9 days to determine the effect of X-irradiation on objective and sensory quality attributes. Irradiation at 0.25 kGy, as a minimum dose, has been approved as a quarantine treatment for the export of tropical fruits grown in Hawaii. The effects of irradiation and storage on specific sensory attributes were dependent on the specific fruit. Aroma and flavor tended to be more intense in the irradiated fruit. Firmness decreased as a result of irradiation and storage, though significant only in rambutans. The color of the rambutans and oranges were significantly affected by irradiation. Irradiation did not contribute to significant changes in the ascorbic acid and carotenoid contents, pH, titratable acidity, and total soluble solids. Adaptation of X-ray irradiation as a quarantine treatment should enhance the marketability of tropical fruits.

A descriptive analysis panel developed terms to describe aroma and flavor of soymilk. Panelists evalu- ated a commercial soymilk and soymilks processed with beans from the normal or lipoxygenase-free lines. Descrip- tors used to describe "beaniness" were "raw as hexanal" for flavor or aroma, "grassy" flavor, and "sweet as green floral" flavor. High correlations were found among these attributes. Judges were consistent in the use of terminology. "Beaniness" for the normal soymilk was described by the terms "raw aroma as in hexanal" and "raw flavor as in hexanal," while "beaniness" for soymilk from the lipoxygenase-free line was described by the terms "sweet as green floral" and "grassy" flavors.

Jams were produced from fruit of eastern thornless blackberries (Black Satin, Chester, Hull Thornless, and Thornfree cultivars) harvested by hand or machine, of a blend of imported fruit from Yugoslavia and Mexico, and of Marion blackberries from Oregon. Jams were evaluated by 12 trained panelists for color, spreadability, consistency, sweetness, blackberry flavor, off-flavor, and seediness. Jams made from hand-harvested Marion, and Black Satin were the most red-purple in color. Machine-harvested Chester fruit yielded the firmest jam and was among the jams rated with the thickest mouthfeel. Jams of hand-harvested Thornfree and Black Satin fruit were rated sweetest. No differences were noted among cultivars in seediness or blackberry flavor. Jam of Marion, Black Satin, and Chester fruit had less off-flavor than the imported fruit blend and Thornfree; however, the intensity of off-flavor was scored low in all jams. Jams made from hand-harvested blackberries were less seedy and had more intense blackberry flavor than machine-harvested fruit.

Fibers were produced from soy protein isolate by both wet-spinning and extrusion. In the wet-spinning process, aged, alkaline protein solution was forced through a spinnerette into an acid coagulating bath. In the extrusion process, a twinscrew extruder forced a protein isolate-water mixture through a die. The physical properties of the fibers were measured at various water activities. The fibers produced by both methods were brittle and lacked tensile strength (tenacity). The addition of glycerol reduced brittleness in extruded fibers. Zinc and calcium ions decreased the brittleness of wet-spun fibers. The tenacity of soy fibers was significantly improved by post-spinning treatments, including acetic anhydride, acetaldehyde, glyoxal, glutaraldehyde, a combination of glutaraldehyde and acetic anhydride, and stretching. The best extruded fibers were produced with a mixture of 45% soy protein, 15% glycerol, and 40% water, finished with a combination of glutaraldehyde and acetic anhydride and then stretched to 150% their original lengths. The best wet-spun fibers were produced with a 19.61% soy protein suspension at pH 12.1; coagulated in a 4% hydrochloric acid solution that contained 3.3% sodium chloride, 3.3% zinc chloride, and 3.3% calcium chloride; and followed by treatment with 25% glutaraldehyde and stretching to 170% their original lengths.

Fresh ‘Tristar’ strawberries were treated by electron beam irradiation to determine the effects on postharvest quality attributes and shelf life. The intensity of red color rated by sensory panelists decreased as irradiation dosage increased from 0 to 2 kGy. Hunter ‘L’ values were higher for fruit treated with 2 kGy than for 0 and 0.5 kGy. Instron firmness values were lower for all irradiated fruit than for control fiuit. Panelists rated irradiated fruit less firm than nonirradiated fruit stored 1, 2 and 4 days. An increase in off-flavor was noted among all treatments stored 6 and 8 days. Irradiation suppressed fungi on stored berries. Irradiation doses of 1 and 2 kGy extended shelf life 2 and 4 days, respectively. Electron beam irradiation technology has excellent potential for extension of shelf life of fresh strawberry fruits.

It is well known that the foaming properties of egg white protein are significantly reduced when a small amount of yolk is mixed in the white. To improve foaming properties of yolk-contaminated egg white protein, soy protein isolate (SPI) and egg proteins were modified to make basic proteins, and effects of these modified proteins on egg white foaming were evaluated in a model and an angel cake system.SPI and egg yolk proteins were modified to have an isoelectric point of 10, and sonication was used to increase protein dispersibility after the ethyl esterification reaction. However, only the addition of sonicated and modified SPI (SMSPI) showed improvement of foaming in the 5% egg protein model system with 0.4% yolk addition. SMSPI was then used in making angel food cake to examine whether the cake performance reduction due to yolk contamination of the white would be restored by such alkaline protein. Cake performance was improved when cream of tartar was used together with SMSPI.Basic soy protein can be made and used to improve egg white foaming properties and cake performance.

Dry- and wet-milled corn germ flour at levels of 0, 2.5 and 5% were added to ground pork of three fat percentages. Raw patties were analyzed for fat, moisture and protein contents and for color. Selected patties, broiled to 77°C, were evaluated for proximate composition, total cooking loss, color and Instron compression. Dry- and wet-milled germ flour addition at the 5% level decreased cooking losses 9 and 7.5%, respectively, when compared with control patties. Instron compression values decreased as the amount of dry-milled germ flour increased. The yellow color (b-value) increased and lightness (L-value) decreased with addition of wet-milled corn germ flour.

Chemical, physical and sensory properties of cooked frankfurters of three fat levels with 0 and 3.5% dry-milled corn germ (DMG) flour and 0 and 3.5% wet-milled corn germ (WMG) flour added were investigated. As fat level increased, cooking losses increased and Instron compression values decreased, in cooked frankfurters with DMG and WMG flours. Addition of DMG flour decreased fat content and lightness (L) and increased yellowness (b-value) of cooked frankfurters. Sensory evaluation indicated that DMG flour in frankfurters decreased tenderness, juiciness and cured flavor intensity. The addition of DMG flour increased chewiness of frankfurters. WMG flour addition decreased fat and protein contents and lightness (L) and increased hue angle (due to higher b), Instron compression values and cooking loss. Cured flavor intensity decreased and off-flavor intensity increased with the addition of WMG flour to frankfurters.

Corn gluten meal and zein at levels of 0, 2.5 and 5% were added to ground pork of three fat percentages. Raw patties were analyzed for fat, moisture, protein contents and color. Selected patties, broiled to 77°C, were evaluated for proximate composition, total cooking loss, color and Instron compression. Five percent zein added to ground pork reduced cooking loss 4.2% when compared with ground pork without zein. Addition of corn gluten meal to pork did not influence yield. Instron compression values increased with the addition of zein and corn gluten meal. Increased fat altered the hue (increased hue angle due to increased b) of the interior of the cooked pork patties. Zein addition also increased the lightness of cooked pork patties. The addition of zein to ground pork patties decreased sensory tenderness and pork flavor intensity and increased off-flavor intensity.

Fresh Tristar' strawberries were irradiated with electron beam irradiation at 0, 1, and 2 kGy. Fruit firmness decreased as irradiation dose increased. Water-soluble pectin increased and oxalate-soluble pectin decreased at 0 and 1 day after 1 and 2 kGy irradiation. Fruit firmness correlated with oxalate-soluble pectin content. Total pectin and nonextractable pectin were not affected by irradiation. The oxalate-soluble pectin content and firmness of irradiated strawberries increased slightly at the beginning of 2°C storage and then decreased as storage time increased. No changes occurred in water-soluble pectin, nonextractable pectin, or total pectin during storage.

Two Escherichia coli O157:H7 strains, SEA 13 B88 gfp 73ec and B6-914 gfp 90ec, together with two bacteria, three yeasts, and two molds that were randomly selected from a collection of microorganisms found on apples or in apple cider, were inoculated into apple cider and subjected to electron beam irradiation at several doses between 0.0 and 2.3 kGy at the Iowa State University Linear Accelerator Facility. The D-values for the E. coli O157:H7 strains ranged between 0.25 and 0.34 kGy; the D-values for most of the normal flora from apples ranged between 0.24 and 0.59 kGy. By taking into account possible variations in treatment conditions, it was calculated that irradiation at 2.47 kGy should achieve a 5-log reduction of E. coli O157:H7 in apple cider at the 95% confidence level. Naturally occurring yeasts might survive such irradiation treatment.

The successful incorporation of fresh fruit and vegetables in the diet of astronauts in space would require that these products are free of foodborne pathogens and retain desirable quality characteristics during storage, This study evaluated 200 or 500 ppm sodium hypochlorite, 5% (w/v) hydrogen peroxide (H 2 O 2 ); and 1% (w/v) PRO-SAN, a biodegradable foodgrade sanitizer, for inactivating pathogenic bacteria on whole tomatoes and improving the shelf-life of these products. Tomatoes were inoculated with a 5-strain mixture of nalidixic-acid-resistant Escherichia coli O157:H7 or Salmonella spp (∼ 10 8 CFU/tomato) to facilitate selective isolation of the pathogens from inoculated tomatoes without interference from the natural microflora. The inoculated tomatoes were immersed for 4 min in distilled water (control) or in each sanitizer at ambient temperature (23 C) then rinsed for 5 s in fresh distilled water. Some of the treated tomatoes (non-rinsed) were stored at 23°C for 8 days. Viable pathogens on tomatoes were evaluated immediately after treatment and at set intervals during storage. Non-inoculated tomatoes were exposed to basically the same treatments then subjected to visual, chemical, and physical analyses at set intervals during storage at ambient temperature. PRO-SAN consistently reduced initial populations of each pathogen on tomatoes by more than 3 log cycles. Log reductions from washing tomatoes with water, sodium hypochlorite and H 2 O 2 ranged from 1.60 to 2.37 for Salmonella and 1.07 to 2.79 for E. coli O157:H7. Populations of Salmonella survivors on tomatoes remained relatively constant during storage; however, significant decreases in E. coli occurred only on PROSAN-treated tomatoes at day 8 of storage (P

Serious outbreaks of illness in 1996 and 1999 linked to contamination of apple cider by E. coli O157:H7 have contributed to intense public concern regarding the safety of fresh apple cider. In response to this concern, the Food and Drug Administration (FDA) has proposed more stringent regulations on the production of apple cider including a requirement to reduce microbial contaminants by 5 logs (Terpstra, 1997). Currently, FDA requires a warning statement on all fruit and vegetable juice products that have not been pasteurized (FDA, 1998). The safety concerns associated with fresh apple cider have contributed to a need to evaluate new approaches to cider processing to provide a safe product without sacrificing quality (Terpstra, 1997).

Processing treatments used to produce a microbiologically "safe" apple cider were evaluated to determine the impact of these treatments on the overall flavor characteristics. Apple cider with (0.1%) and without (0%) potassium sorbate was subjected to four processing treatments: untreated, irradiated at 2 kGy, irradiated at 4 kGy, and pasteurized. Volatile flavor compounds were isolated from the cider using solid-phase microextraction methods with gas chromatographic analysis. A trained descriptive analysis panel evaluated sensory attributes. The effects of the processing treatment were dependent on the presence of sorbate in the apple cider. Irradiation treatments resulted in a decrease in the content of esters characteristic of apple flavor and an increase in the content of alcohols and aldehydes formed through lipid oxidation reactions. The presence of sorbate reduced the effects of the irradiation treatments on these volatile flavor compounds. Sensory panelists, however, detected higher intensities of undesirable flavor attributes, including "cardboard flavor", and lower intensities of the desirable "apple flavor" in irradiated cider with added sorbate.

The objectives of this study were to determine if washing of whole apples with solutions of three different sanitizers (peroxyacetic acid, chlorine dioxide, or a chlorine-phosphate buffer solution) could reduce a contaminating nonpathogenic Escherichia coli O157:H7 population by 5 logs and at what sanitizer concentration and wash time such a reduction could be achieved. Sanitizers were tested at 1, 2, 4, 8, and 16 times the manufacturer's recommended concentration at wash times of 5, 10, and 15 min. Whole, sound Braeburn apples were inoculated with approximately 1 x 108 or 7 x 106 CFU per apple, stored for 24 h, then washed with sterile water (control) or with sanitizers for the prescribed time. Recovered bacteria were enumerated on trypticase soy agar. Washing with water alone reduced the recoverable population by almost 2 logs from the starting population; this can be attributed to physical removal of organisms from the apple surface. No sanitizer, when used at the recommended concentration, reduced the recovered E. coli population by 5 logs under the test conditions. The most effective sanitizer, peroxyacetic acid, achieved a 5-log reduction when used at 2.1 to 14 times its recommended concentration, depending on the length of the wash time. The chlorine-phosphate buffer solution reduced the population by 5 logs when used at 3 to 15 times its recommended concentration, depending on wash time. At no concentration or wash time tested did chlorine dioxide achieve the 5-log reduction.

Sensory and objective attributes of fresh fruit of five locally grown day-neutral strawberry (Fragaria × ananassa Duch.) cultivars (Tristar, Tribute, Mrak, Yolo, and Selva) were compared to those of California-grown strawberries available in the Iowa markets. `Tristar' and `Tribute' fruit were redder and more sour than fruit of other day-neutral cultivars, and `Tristar' fruit were the most juicy of the berries evaluated. `Tristar' and `Tribute' fruit had higher titratable acidity and lower Hunter L (lightness) values than those of other evaluated fruit. Sensory panelists rated the California-grown berries as the least red.

Eight treatment combinations for the formulation and heating of fresh ground pork were investigated: four raw fat levels (4, 9, 18, 23%) and two internal end point temperatures (71°C and 77°C). In the raw state, ground pork containing 4 or 9% fat contained less cholesterol, more moisture and was judged to be more red than samples containing 18 or 23% fat. Tenderness, juiciness and amount of mouthcoating increased as fat level in the cooked patties increased. Internal end point temperature (71°C or 77°C) did not affect sensory scores of cooked pork patties. Cooked patty cholesterol content (wet weight) did not differ among the four fat levels. High-fat ground pork retained less cholesterol than low-fat ground pork.