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Ten novel breeding lines of quinoa (Chenopodium quinoa Willd) suitable to be grown in the Pacific Northwest of the United States were developed and utilized for extrusion processing. Understanding how a particular breeding line performs during food processing and which properties determine its performance can promote the use of quinoa as an ingredient in value‐added products, such as extruded snacks. In this study, extrusion characteristics of the whole seed flours of the novel quinoa breeding lines were evaluated using a co‐rotating twin‐screw extruder at two temperatures (110°C and 125°C), three screw speeds (200, 350, and 500 rpm), and a moisture content of 18% (w.b.). The expansion ratio (ER) ranged from 1.15 to 2.33 and was negatively influenced by the fat content in the flours. Breeding line 11WAQ‐104.88 (WAQ10) exhibited the greatest potential for use in direct expanded foods as it had the highest ER for all conditions studied. Strong correlations were found between ER and pasting properties of the flours, proving the usefulness of the pasting test for flour quality evaluation before extrusion processing. The results demonstrate the potential of using quinoa for producing direct expanded food products and highlight the importance of selecting specific breeding lines for desired product characteristics. Practical Application: This study provides the extrusion processing characteristics of 10 new quinoa breeding lines. Based on the information gained, it will be easier for the food industry, including breeders as well as processors, to select the right quinoa variety based on their requirements, and may further help to enhance the use of quinoa. [ABSTRACT FROM AUTHOR]

Ten advanced breeding lines of quinoa were evaluated for their physicochemical and functional characteristics. These novel breeding lines were used in two model foods, including cookies and cooked grains, to understand the influence of their characteristics on the product quality. The cookies were baked using whole quinoa flour, and the quality attributes of texture, physical dimensions, and color were measured. The whole quinoa grains were cooked with water at a 1:4 (w/w) grain‐to‐water ratio, and quality attributes including water uptake (WU‐G), bulk density (BD‐G), and cooking loss (CL‐G) were measured. Significant differences in the quality of both products as an impact of the breeding lines were observed. In baked cookies, the WAQ2 variety produced cookies with the lowest diameter, whereas cookies prepared with WAQ1 were significantly softer than other varieties. In terms of cooked quinoa, WAQ8 exhibited the highest WU‐G while WAQ1 showed the highest CL‐G. Correlations were observed between flour characteristics and final product quality. Cookie height was negatively correlated with protein content, whereas the water solubility index (WSI) of flours had a positive effect on the cookie hardness. The cooking characteristics of quinoa grains were found to be correlated with the thermal properties of whole quinoa flour. The results of this study will help determine the advanced breeding lines for release as commercial varieties and will also provide food processors with information to find suitable quinoa varieties for different food applications. Practical Application: New quinoa breeding lines have been developed to be grown in the climate conditions of Washington State. These varieties were characterized to find correlations with food quality for cookies and cooked grains. The results from this study will help farmers navigate among the quinoa varieties and help commercial food producers use the optimal quinoa variety for their specific food products. [ABSTRACT FROM AUTHOR]

This study investigated the decontamination efficacy of washing treatments for whole fresh apples by using washes containing surfactants, lauric arginate, sodium dodecyl sulfate, and Tween 20, combined with peracetic acid (PAA), followed by hot air impingement drying. Whole fresh apples of selected varieties (Gala and Granny Smith) were inoculated with Listeria innocua (7 log CFU/mL) by using a dipping method, and then dried and subjected to wash treatments with selected washing solutions (H2O, PAA, PAA–lauric arginate, PAA–sodium dodecyl sulfate, and PAA–Tween 20), followed by hot air impingement drying at two different temperature and time conditions, 93°C for 60 s or 121°C for 25 s. The H2O and PAA wash followed by hot air impingement drying led to a maximum 1.5-log reduction of L. innocua on the fruit surface. Adding surfactants increased the effectiveness of washing and drying treatments, resulting in an approximate 2.2-log reduction. Surfactants increased the spreadability and evaporation rate of the washing solutions. Posttreatment changes in apple firmness were assessed during a 21-day storage at 4 and 21°C. The hot air impingement drying had no adverse effect on the firmness of the apples and did not show any further reduction in L. innocua. Washing apples with solutions containing surfactants combined with PAA followed by hot air impingement drying helped to reduce the microbial loads to some extent and may help to reduce drying times significantly. Hot air impingement drying had no adverse effects on the quality of the apples. Surfactants increased the spreadability and evaporation rate of the washing solutions. Apple surface irregularities protect the microorganisms from wash treatments. Applied treatments resulted in a maximum 2.2-log reduction of L. innocua. [ABSTRACT FROM AUTHOR]

Nuña bean, also known as "popping" bean, belongs to the group of common beans (Phaseolus vulgaris, L.). Originated in Andean mountains, nuña beans is an important food crop in several South American countries, including Bolivia, Ecuador, and Peru, where it is consumed primarily as a snack. Nuña beans are highly nutritious and have a distinctive nutty flavor, which makes them potentially desirable ingredients in food applications, such as extruded snacks. Thus, the goal of this study was to evaluate the performance of whole seed nuña bean flour during extrusion cooking. Expansion characteristics of whole nuña bean flour were investigated using a twin‐screw extruder. Three levels of moisture contents of 15%, 18%, and 21% (wet basis), three barrel temperatures of 120, 140, and 160 °C, and three screw speeds of 150, 200, and 250 rpm were evaluated, with a die diameter of 3.15 mm. The expansion ratio (ER) ranged from 1.41 to 3.03, within the extrusion conditions studied. The moisture content and screw speed were found to have the most significant impact on the ER. Lower temperature and higher screw speed resulted in higher ER. The maximum ER of 3.03 was observed at a moisture content of 15%, a barrel temperature of 120 °C, and a screw speed of 250 rpm. Nuña bean flour exhibited good expansion properties at relatively low temperatures, which highlights its potential for use in extruded food applications such as nutritious snacks. Practical Application: There is increasing consumer demand for more nutritional snacks and cereals. Nuña bean flour exhibited potential for use in such nutritious products. This provides the industry with an alternative source of protein and fiber for inclusion in expanded food products. [ABSTRACT FROM AUTHOR]

Large amounts of water used in the apple packing process, the presence of organic matter, and difficult-to-clean equipment are vectors for contaminating apples with foodborne pathogens, such as Listeria monocytogenes. There is a need to develop new cleaning methods for fresh apples and evaluate their antimicrobial efficacy. A series of surfactants of different chemical properties (cationic lauric arginate [LAE], anionic sodium dodecyl sulfate [SDS], and nonionic Tween 20 [T20]) alone and combined with peracetic acid (PAA) were evaluated for their efficiency in the removal of L. innocua, a surrogate of L. monocytogenes, from fresh apples. Whole fresh apples were inoculated with L. innocua (7 log CFU/mL) by a dipping method, dried, and subjected to wash treatments with selected cleaning solutions (water, PAA, PAA-LAE, PAA-SDS, and PAA-T20). The contact angle between the cleaning solutions and the surface of the apples was measured. The antimicrobial activity of the cleaning solutions and the efficacy of the cleaning treatment were evaluated by enumeration of L. innocua from treated apples and visualized by scanning electron microscopy. Stem bowl and calyx cavities of the apple harbored higher bacteria concentrations (∼4.82 log CFU per apple), compared with the equatorial section (∼2.66 log CFU per apple). Addition of 0.1% of selected surfactants led to a significant decrease in surface tension of cleaning solutions and allowed better spreading on the apple surface. Surfactants combined with PAA solution resulted in higher L. innocua reduction compared with PAA alone; however, their efficacy was limited. The most effective cleaning solution was PAA-T20, with reduction of approximately 2.2 log. Scanning electron microscopy imaging confirmed that most bacteria were harbored inside the surface irregularities. PAA alone and with surfactants caused damage and deformation of bacteria cells. Cleaning apples with PAA combined with surfactants may improve microbial safety in whole apples; however, the efficiency of the decontamination treatment can be reduced because of variations in apple morphology. [ABSTRACT FROM AUTHOR]

The industrial apple packing process begins with submerging the harvested or stored apples into the water dump tank and carrying them by water flumes through various washing steps before drying and packing. Constant introduction of organic matter and water recirculation introduces the risk of apples being cross-contaminated with pathogenic bacteria such as Listeria monocytogenes . This study investigated the relationship between the apple peel microstructure and attachment of bacteria in an aqueous environment. Whole fresh apples of three varieties (viz., Gala, Golden Delicious, and Granny Smith) were inoculated with L. innocua , a surrogate strain of L. monocytogenes , by submerging the apples into the inoculum solution containing ∼10 6  CFU/mL level. Apples were carefully turned around in the inoculum for 10 min simulating industrial dump tank and fumes conditions. Attachment of L. innocua , to different apple peel sections, was demonstrated using scanning electron microscopy (SEM). Textural characteristics varied considerably among apple varieties. Generally, the apple peel was covered with an amorphous layer of wax, disrupted by microcracks, lenticels, and occasionally overlaid with various types of epicuticular wax platelets. Listeria innocua attached primarily to the apple peel in the stem bowl and calyx sections, embedding in the microcracks, lenticels and on the surface of the trichomes. Bacteria were difficult to locate on the smooth peel surface in the equatorial section of the apples. Results provide valuable information on Listeria attachment on apples which can be used in developing new intervention methods of microbial decontamination. [ABSTRACT FROM AUTHOR]

Direct steam injection (DSI) processing with pH adjustment was investigated to enhance the functionality of pea-rice protein isolate blends (PR). Protein slurries at concentration of 5% (w/w) of commercial pea and rice protein isolates in the ratio of 2:1 (w/w) across a range of steam temperatures (66–107 °C) and pH values (2 −1 1) were studied. After DSI treatment, the PR were freeze-dried to obtain the final dry protein powder. Based on protein solubility profiles, the optimal DSI processing conditions were 107 °C and pH 11. Available lysine was not reduced (P > 0.05) in the blend. Solubility (from 3 to 41%, at pH 7), emulsifying activity index (from 5.9 to 52.5 m 2 /g), foam stability (from 68.2 to 82.8%), and oil holding capacity (from 1.8 to 4.9 g/g) values increased (P < 0.05) compared to the untreated PR. DSI can modify the functionality of PR without affecting the essential amino acid composition. [ABSTRACT FROM AUTHOR]

Screw profile design is crucial to the amount of shear and mechanical energy that is imparted on the material being extruded. A genetic algorithm model, in combination with a neural network fitness function, was developed to predict screw profile design. Model was then used to predict the necessary screw profiles along with the necessary process conditions needed for different target products. Predicted screw profiles and extrusion conditions produced expected values of pressure, motor torque, specific mechanical energy (SME), expansion ratio (ER), water absorption (WAI), and water solubility (WSI). Neural network models displayed high R2 values (>0.979) for the process responses of pressure, motor torque, and SME, and slightly lower R2 values for product responses of ER (0.935) WSI (0.900), and WAI (0.847). This demonstrates the possibility for quick predictions of optimum screw profile designs for achieving desired characteristics in the final extrudates. • Screw profile design is crucial to the amount of energy imparted to the raw materials. • Arranging the order of screw elements can be complex and difficult. • A genetic algorithm model with a neural network fitness function was developed. • The developed model determined a screw profile that resulted in desired levels of energy. [ABSTRACT FROM AUTHOR]

Adequate surrogate identification is critical for validating in-plant thermal process controls for Salmonella inactivation in different food matrices. This study compared the thermal inactivation parameters (D- and z-values) and evaluated the heat resistance of Enterococcus faecium (8459) as a surrogate for a 5-serovar Salmonella cocktail in cornmeal. The cornmeal was spray inoculated with the respective bacteria to achieve ~9 log CFU/g population and set to the desired moisture contents (16, 22, and 28% w.b.). The inoculated cornmeal was then heat-treated at pre-determined temperatures (60, 64, and 68 °C) in sealed aluminum thermal-death-time disks in hot water baths for pre-determined time intervals. Injury-recovery media [brain heart infusion (BHI) agar overlaid with xylose lysine deoxycholate (XLD) agar for Salmonella or BHI agar overlaid m-enterococcus agar for E. faecium ] were used for microbial enumeration to account for thermally injured bacterial cells. The D-values of Salmonella in cornmeal at 16, 22, and 28% moisture content were 37.5, 8.4, and 2.4 min at 60 °C, 19.9, 3.5, and 1.1 min at 64 °C, and 10.1, 1.4, and 0.5 min at 68 °C, respectively. The D-values of E. faecium in cornmeal at 16, 22, and 28% moisture content were 140.4, 18.9, and 3.3 min at 60 °C, 78.4, 7.1, and 1.6 min at 64 °C, and 37.3, 2.8, and 0.8 min at 68 °C, respectively. The z-values of E. faecium and Salmonella in cornmeal at 16, 22, and 28% moisture content were 13.9, 9.7, and 12.5 °C, and 14.0, 10.4, and 11.7 °C, respectively. These results indicated similar or higher thermal resistance (D-values) and equivalent thermal sensitivity (z-values) of E. faecium compared to Salmonella at different moisture contents and respective temperatures (P ≤ 0.05). Therefore, E. faecium could be used as a surrogate for Salmonella during thermal process validation of cornmeal processing. • E. faecium showed higher thermal resistance (D- values) in cornmeal compared to Salmonella. • Thermal sensitivity (z-values) of E. faecium and Salmonella were similar at different moisture contents (16, 22, and 28%, wb). • E. faecium can be considered as fail-safe Salmonella surrogate for the thermal process validation of cornmeal. [ABSTRACT FROM AUTHOR]