Progress 01/01/08 to 12/31/08
OUTPUTS: Two graduate (M.S.) students, a postdoc researcher, and a lab manager were involved in this project utilizing facilities in the School of Food Science in Univ. of Idaho. Research topics for the students' degree were derived from this project. Results from the research have been presented in a food science international conference (Institute of Food Technologists (IFT)) and prepared for publication in peer-reviewed scientific journals. Provisional patent applications have been made using data from this project. PARTICIPANTS: (1) Murali Krishna, Graduate (M.S.) student, School of Food Science (SFS), Univ. of Idaho (UI) (2) Nageshwar Tammineni, Graduate (M.S.) student, SFS, UI (3) Ho Jin Kang, Post-doc researcher, SFS, UI (4) Kathy Hendrix, Lab technician, SFS, UI (5) Caleb I. Nindo, Assistant Professor, SFS, UI (6) Shyam S. Sablani, Assistant Professor, Biological Systems Engineering (BSE), Washington State Univ. (WSU) (7) Florian Dasse, Grad student, ENSAR, Rennes, France (8) Luis Bastarrachea, Grad student, BSE, WSU (9) Sumeet Dhawan, Grad student, BSE, WSU TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
A. Development of biopolymer films from potato peels, trout skin gelatin, and apple peels (1) Potato peel-based films: As processing pressure increased, the G' and the viscosity (at 90 C at 30 min) of the solution prepared with 10 passes increased. Those values of the solution prepared at 207 MPa increased as the number of passes increased. Water diffusivity and WVP decreased with low levels of glycerol. The water vapor permeability (WVP) increased as the glycerol content increased irrespective of the pressure and the number of pass. (2) Trout skin gelatin-based films: The G' values did not change dramatically (0.1-1.2 Pa), while the viscosity values increased steadily with time from 12 to 24198 Pa-s at 90 C. Tensile strength, % elongation at break, elastic modulus, water vapor permeability, % solubility, and CIELAB coordinate L*, a*, and b* values were 25.9 MPa, 17.3 %, 790.5 MPa, 2.7 g-mm/kPa-h-m2, 86.1 %, 88.5, -1.0, 2.6, respectively. (3) Apple peel-based films: The G' and viscosity decreased significantly with increasing processing pressure. The viscosity decreased from 644 to 468 kPa-s as the pressure increased from 138 to 207 MPa at 90 C. The monolayer water content decreased with increasing content of glycerol from 23 to 33%. Further increase in glycerol content did not change the monolayer water content. The water diffusion coefficient was highest at the intermediate level of glycerol content. WVP and oxygen permeability increased with increasing level of glycerol, while processing pressure did not influence the gas barrier properties of the films. The film prepared at 207 MPa was less stiff and strong, but more stretchable than those prepared at 138 and 172 MPa. B. Inhibition of Listeria monocytogenes by potato peel-based films with oregano essential oil An oil concentration of 30 µL/mL produced clear zones of inhibition. When the oil was incorporated into the PP film matrix, it continued to be active against Listeria monocytogenes at 10^4-10^6 CFU/plate. Films with 2% and 4% oil concentration produced clear zones of inhibition. The WVP values decreased significantly from 3.5 to 2.7 g-mm/kPa-h-m^2 as the concentration of oil increased from 0 to 2% in the film. As the concentration of oil in the film increased from 0 to 2%, TS and EM values decreased significantly from 6.3 to 2.9 MPa and 257.0 to 107.0 MPa, respectively. C. Physical and moisture barrier properties of fish gelatin films from extrusion Edible films with 1:0.2 and 1:0.25 ratios were successfully extruded with the temperatures of 110 and 120 C, a screw speed of 250 rpm, a liquid feed rate of 11 g/min, and a solid feed rate of 9 g/min. The 1:0.25 ratio extruded films had the highest % elongation (158.4%), while 1:0.2 ratio casted films had the highest tensile strength (26.4MPa). The WVP was higher for extruded films than casted films at the same gelatin-glycerol ratio, with WVP of 5.61 g-mm/(kPa-h-m2) being the lowest among the extruded films. The Tg of extruded films increased as temperature of the extrusion increased. The 1:0.2 films extruded at 110 C had the lowest Tg of 12.4 C.
- ABSTRACTS: 1. Hendrix, K.M., Jin, T., and Min, S. 2008. Development of mustard meal co-product-used biopolymer edible films for food packaging. Institute of Food Technologists Annual Meeting. 053-14. June 30, 2008, New Orleans, LA.
- 2. Hendrix, K.M. and Min, S. 2008. Biopolymer films from trout skin gelatin and commercial deep sea fish gelatin compared to whey protein films. 053-11. June 30, 2008, New Orleans, LA.
- 3. Kang, H.J., Jin, T., and Min, S. 2008. Development of a potato peel-based edible film using high-pressure homogenization, ultrasound treatments and irradiation. Institute of Food Technologists Annual Meeting. 053-02. June 30, 2008, New Orleans, LA.
- 4. Kang, H.J. and Min, S. 2008. Antioxidant activity of a potato peel extract as a natural antioxidant. Institute of Food Technologists Annual Meeting. 096-47. June 30, 2008, New Orleans, LA.
- PAPER & PAPER IN PROCEEDINGS: 1. Min, S. and Choi, Y. J. 2009. Microbial Modeling in Quantitative Risk Assessment for the Hazard Analysis and Critical Control Point (HACCP) System: A Review. Food Sci Biotechnol.
- 2. Min, S.C., Kim, Y.T., and Han, J.H. 2009. Packaging and the Shelf Life of Cereals and Snack Foods. In: Robertson, Gordon L., editor. Food Packaging and Shelf Life: A Practical Guide. Oxford, UK: CRC Press, Taylor & Francis Group.
Progress 01/01/07 to 12/31/07
OUTPUTS: 1. Antioxidant activity of potato peels was determined as a background study for developing edible biopolymer edible films from potato peels. 2. Biopolymer films were developed from potato peels and fish skin gelatin. 3. Extrusion conditions were determined for producing whey protein films.
PARTICIPANTS: Kathy Hendrix, Department of Food Science and Toxicology, University of Idaho, Moscow, ID. Ho Jin Kang, Department of Food Science and Toxicology, University of Idaho, Moscow, ID. Armando McDonald, Department of Wood Chemistry & Wood Composites, University of Idaho, Moscow, ID. Tony Jin, Food Safety Intervention Technologies Research, United States Department of Agriculture, Wyndmoor, PA.
TARGET AUDIENCES: Potato and trout process industries.
1. Antioxidant activity of a potato peel extract as a natural antioxidant: The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and the 2- thiobarbituric acid reactive substances (TBARS) value test were conducted to determine antioxidant activity of potato peels. The results from the TBARS test indicated that a potato peel extract is a potential material to be used as a natural food antioxidant. 2. Development of edible biopolymer edible films: A potato peel solution was treated by homogenization at high-pressure (22,000 psi, 25-50 C), ultrasound (400 W, 24 kHz, 120 micrometer, 30-60 C, 30 min), or gamma-irradiation (10-20 kGy) to obtain small biopolymer particles in the solution. A fish skin gelatin solution was prepared with tout skin-extracted gelatin and commercial fish gelatin (6.8% (w/w)). The solutions were heated to 90 C for 30-60 min. After cooling, 10-100% (w/w) glycerol of potato peel was added to form a film-forming solution. Films were formed
by casting degassed film-forming solutions and their film properties of tensile properties, water vapor permeability, water solubility, and color (lightness) were measured. The film properties of the potato peel-based film produced from the homogenized (22,000 psi) film-forming solution were better than those of the films from the solutions treated by ultrasound or irradiation. The tensile strength, % elongation at break, and elastic modulus, water vapor permeability, and solubility of the film were 4.9 MPa, 14.4%, 101.7 MPa, and 27.4%, respectively. The fish gelatin films exhibited better film properties compared to the WPI films, with the exception of solubility. The tensile strength, % elongation at break, elastic modulus, and water vapor permeability of the films were 10.6 MPa, 6.2 %, 313.7 MPa, and 3.5 g-mm/kPa-h-m2, respectively, for trout skin films, 23.0 MPa, 37.3 %, 600.5 MPa, and 2.3 g-mm/kPa-h-m2, respectively, for commercial fish gelatin films. Trout gelatin films and
commercial fish gelatin films had 76.4 and 100% (w/w) soluble matters, respectively, as compared to WPI at 19% soluble matter. Fish gelatin films have slightly better clarity than WPI films. Potato peels and fish (trout) skin waste have potential value as protein and natural product sources that can be utilized to form biopolymer films for practical applications in the food industry. 3. Production of whey protein edible films by extrusion: Extrusion was investigated for producing whey protein films in a large scale. A co-rotating twin screw extruder (Haake-Leistritz Micro-18, Sommerville, NJ) was used to produce the films. The screw speed and the production temperature were controlled at 200-300 rpm and 120-150 C, respectively. We identified temperature profiles in barrel, screw type, screw speed, production rate (wet feed and dry feed), water content, and plasticizer (glycerol) content as major variables in producing whey protein films by extrusion. Whey protein-based sheets
containing 48.8% glycerol (dry basis) were obtained at screw speeds of 200, 225, 275, and 300 rpm. Feed rates were proportionally decreased or increased depending on the screw speed.
- No publications reported this period