TEXTURE PROFILE METHODS

1. TEXTURE PROFILE METHODS

2. Texture Profile • Provides quantitative description of attributes important to food texture • Developed in 1960s in analogy to “flavor profiling” of A. D. Little (1940s) • Civille and Szczesniak (1973) and Civille and Liska (1975) instrumental to development

3. Initiated by understanding that texture was: • A sensory property, more than just a force-deformation relationship • Made up of many parameters; most are tactile, some are visual or aural • May be described by imprecise terminology • Had characteristics that appear in predictable orders

4. Definitions: Texture • The visual or tactile surface characteristics of something (Webster's definition 3b) • is a sensory attribute, perceived by the senses of touch, sight and hearing (Brennen) • Sensory manifestation of the structure of inner makeup in terms of their: • 1.Reaction to stress measured as mechanical properties by kinesthetic sense in the muscles of the tongue, jaw and lips. • 2.Tactile properties measured as geometrical or moisture properties by tactile nerves in surface of the skin of lips or tongue (Meilgaard, Civille, Carr, 1991)

5. Szczesniak (1963) developed set of textural characteristics related to popular terms

6. Geometrical Properties

9. Also, things happen in predictable order

10. Visual Geometric and Surface properties FIRST BITE MECHANICAL GEOMETRICAL Fracturability Any geometric properties depending upon the product Viscosity Firmness MASTICATION (early) MECHANICAL GEOMETRICAL Fracturability Any geometric properties depending upon the product Firmness Viscosity MASTICATION (late) MOISTURE BREAKDOWN FAT MOUTH-COATING Type Rate Adsorption Release Release Mouth- Type Amount coating SWALLOWING Ease of Throat-Coating RESIDUAL MOUTH-COATING THROAT-COATING GENERAL FEEL ON: Type Amount Type Amount Mouth Throat

11. In texture profile analysis attributes are defined • Order and method of processing is considered

12. Texture Profiling Method The sensory analysis of the texture complex of a food in terms of its mechanical, geometrical, fat and moisture characteristics, the degree of each present, and the order in which they appear from first bite through complete mastication.

13. Panelists • Selected based on ability to discriminate known textural differences • Interviewed to determine interest, availability, and attitude • Trained using a variety of products • May be introduced to underlying textural principles, mechanical forces, strains, etc

14. Character notes • Mechanical, geometric, moisture • Intensity/scaling • Such as 15 cm line scale

15. Order of appearance Prior to mastication First bite First chew Chew down Residual phase

16. Objectives • To eliminate problems with subject variability • To allow direct comparison of results with known materials • To provide a relationship with instrument measures • How • Specific rating scales • Specific reference materials • Meaningful term definitions

17. TPA: The Method • Panelists rate each of the selected attributes according to a standard scale • Scales available for hardness, fracturability, chewiness, guminess, adhesiveness, and viscosity • Scales are quantitative but do not measure a physical quantity or indicate quantitative relationships

18. For Example: Standard Hardness Scale Panelists need to be trained on the scale

19. Specified sensory techniques Hardness Place sample between molar teeth and bite down evenly, evaluating the force required to compress the food Cohesiveness Place sample between molar teeth, compress and evaluate the amount of deformation before rupture

20. Viscosity Place a spoon containing sample directly in front of mouth and draw liquid from spoon over tongue by slurping, evaluating the force required to draw liquid over the tongue at a steady rate. Springiness Place sample either between molar teeth (if it is a solid) or between tongue and palate (if it is a semi-solid) and compress partially; remove force and evaluate the degree and speed of recovery

21. Adhesiveness Place sample on tongue, press it against palate and evaluate force required to remove it with tongue. Fracturability Place a sample between molar teeth and bite down evenly until sample crumbles, cracks or shatters; evaluate force with which sample moves away from teeth.

22. Chewiness Place sample in mouth and masticate at one chew per second and at a force equal to that required to penetrate a gumdrop plus or minus one second; evaluate the number of chews required to reduce sample to a state ready for swallowing. Gumminess Place sample in mouth and manipulate with tongue against palate; evaluate amount of manipulation necessary before sample disintegrates

23. Each attribute has series of 9 standrds Texture Attribute Scale Standard Hardness Low Cream cheese Medium Frankfurter High Hard candy Adhesiveness Low Vegetable oil Medium Marshmallow topping High Peanut butter

24. Texture Attribute Scale Standard Fracturability Low Corn muffin Medium Ginger snap High Hard candy Cohesiveness Low Corn muffin Medium Dried fruit High Chewing gum

25. Texture Attribute Scale Standard Denseness Low Whipped topping Medium Malted milk balls High Fruit jellies Wetness Low Crackers Medium Ham High Water

26. Texture Attribute Scale Standard Adhesiveness to lips Low Tomato Medium Breadstick High Rice cereal Roughness Low Gelatin dessert Medium Potato chip High Thin bread wafer

27. Texture Attribute Scale Standard Cohesiveness of mass Low Licorice Medium Frankfurter High Bread dough Moisture absorption Low Licorice Medium Potato chip High Cracker

28. Texture Attribute Scale Standard Adhesiveness to teeth Low Clam Medium Graham cracker High Jujubes Hardness Low Marshmallow Medium Bread dough High Nougat

29. Example: Terminology for Oral Texture of Cookies

30. Surface Place cookie between lips and • evaluate for: • Roughness: Degree to which surface is uneven (smooth-rough) • Loose particles: Amount of loose particles on surface (none to many) • Dryness: Absence of oil on the surface (oily to dry)

31. First Bite Place one third of cookie between incisors, bite down and evaluate for: • Fracturability: Force with which sample ruptures (crumbly to brittle) • Hardness: Force required to bite through sample (soft to hard) • Particle Size: Size of crumb pieces (small to large)

32. First Chew Place one third of cookie between molars, bite through and evaluate for: • Denseness: Compactness of cross section (airy to dense) • Uniformity of Chew: Degree to which chew is even throughout (uneven to even)

33. Chew Down Place one third of cookie between molars, chew 10 to 12 times and evaluate for: • Moisture Absorption: Amount of saliva absorbed by sample (none to a lot) • Type of Breakdown: Thermal, Mechanical, Salivary (multiple choice, no scale) • Cohesiveness of Mass: Degree to which mass holds together (loose to cohesive) • Tooth Pack: Amount of sample stuck in molars (none to a lot) • Grittiness: Amount of small, hard particles between teeth during chew (none to a lot)

34. Residual Swallow sample and evaluate residue in mouth for: Oily: Degree to which mouth feels oily (dry to oily) Particles: Amount of particles left in mouth (none to a lot) Chalky: Degree to which mouth feels chalky (not chalky to very chalky)

35. Quantitative Descriptive Analysis: General Approach Panelists (10-15) meet to try product and similar products Panelists develop list of attributes pertinent to that group of products

36. Rubbery Sticky Gritty Gooey Chewy Hard Cohesive Firm Falls apart Tender Elastic Sandy Softness Springy All terms may be reduced to a smaller subset, similar terms agreed upon, redundant terms eliminated

37. Develop relative standards for select attributes Some may already be published, or they may need to be developed Provide panelists with scales and test standards

39. Panelists trained with standards 1 2 3 4 5 6 7 8 9

40. Test product of interest evaluated for texture attribute, with standards as reference