2018 ACS BOK – DOMAIN 7 – Assessment and Evaluation of Cheese – Complete Re-Cap by Crystal Schroeder ACS CCP

Common Defects to identify– Listen , Look , Smell, Touch, Taste

– Judging in Competition and Communicating Assessments

Domain 7–Day 3

Good Morning Cheese Study Group–Today we look further into the evaluation and assessment aspect of Domain 7 which naturally leads into a discussion of defects that might be found in cheeses.

PLEASE NOTE: There are two valuable links to use for further study at the bottom of this posting.

Domain 7 – Day 4 Here is the assessment recap from an ACS call in 2014.

CHEESE ASSESSMENT & EVALUATION
– Principles of Sensory Analysis
o Review: 5 senses used for sensory analysis
 Sight
 Smell
 Taste
 Touch
 Sound
o Sensory Analysis used to determine various characteristics of cheese
 These characteristics are linked, so a textural characteristic will be determined by sight and touch; a flavor characteristic determined by smell, taste, and touch (or mouthfeel)
o Each characteristic depends on the ideal qualities of any given cheese
 Each family has ideal qualities and possible defects
 A cheese that carries certain characteristics could be ideal for certain cheeses but defects for others (i.e. eyes are good in some Swiss-type cheeses like Emmentaler, but may be considered a defect in a Gouda or Cheddar)

– Applying the Senses in Cheese Evaluation
o SIGHT: Used mainly for body or texture, color, and eye formation
 BODY characteristics
• may indicate proper or improper curd knitting, moisture control, or proteolytic/lipolytic breakdown
• Creamy, curdy, open, smooth, eyes, firm, crumbly
 COLOR characteristics
• may indicate proper or improper animal feed, curd knitting, or seasonal fluctuation of milk
• Acid-Cut (a color characteristic that is dull, lifeless, or “bleached,” which may imply issues with acid control), mottled, seamy (a color/textural characteristic that shows up as definitive curd lines or “seams,” implying lack of curd knitting or mechanical openings developed), unnatural, wavy
• Colors like white, ivory, butter yellow, golden, orange, flecked, ashed
 EYE FORMATION
• can be ideal or a defect
• if meant to develop eyes, a lack thereof is a defect, while if not meant to develop eyes, their presence may indicate unwanted contamination from gas formers
• Blind (lack of eyes), irregular, overset (imbalanced), one-sided, uneven
 APPEARANCE: Exterior Defects
• Exterior defects indicate age and ripeness based on textural, color and visual cutes; this will indicate flavor development, especially giving clues on overripeness
• RIND: Cracks in the rind, blemishes, unwanted mold growth, slipskin
• SHAPE: Flat or collapsed (uneven turning in affinage), bulging or bloating (unwanted gas formers develop cracks, fissures or eyes)
• TEXTURE: Overripe, excessively runny
 APPEARANCE: Interior Defects
• Interior defects indicate age and ripeness based on textural, color and visual cues; this will indicate flavor development, especially giving clues on overripeness
• COLOR: Too light or too dark (unripe or overaged; also caused by excessive exposure to air)
• TEXTURE: Dry paste (overaged or exposed to air), over-liquified paste (overaged, excessive proteolysis)
o TOUCH/TEXTURE
 OPENNESS: Interior Defects
• Excessive mechanical openings indicate the overproduct of gases in the paste
• for cheeses with a desired open texture (Emmentaler, Jarlsberg) this is not a defect, but in other cheeses this may indicate cross-contamination in animal feed or production facilities
• openness may also indicate improper curd knitting, too little pressing, or improper acid and temperature controls
 OTHER TEXTURAL DEFECTS
• Brittle, greasy, gummy, lumpy, mealy, spongy
o SMELL/ODOR
 Smell is closely linked to flavor through the retronasal effect, which allows volatile scent compounds to hit the back of our throats and flow back up to our taste buds
 Many odors come from volatile compounds that can be helpful or, more often, result in odor and flavor defects (i.e. sulfur, methyl ketones or “cowy” odor/flavor)
o TASTE/FLAVOR
 FLAVOR characteristics
• can be ideal or a defect
• based on five taste buds: sour, salty, sweet, bitter, umami; various compounds relate to each
o Sour is acidity, such as lactic acid
o Salty is from salts, sodium chloride or mineral salts
o Sweet, bitter and umami come from the break down of proteins into peptides and further into amino acids; common compounds such as butyric acid (like body odors), diacetyl (buttery) or methanethiol (cabbage or other cruciferous vegetables)
• most often related to too little or too much of certain flavor characteristics, or to issues in the development and aging of the cheese (i.e. excessive free fatty acid development;
• Acid (too much or too little), barnyard, bitter, rancid, malty, metallic, sour, yeasty
• Flavor and texture are linked in the mouth with mouthfeel, a combination of how something taste with how it feels in the mouth
o SOUND
 Sound in sensory analysis comes mainly from thumping large wheels of cheese as they age, i.e. Emmentaler, Gruyere, Comte, Parmigiano Reggiano
 The sound of a wheel of cheese will determine its interior texture, especially if it has developed unwanted openings in the paste; affineurs can also tell ripeness from thumping the wheels

– Sensory Analysis Environment
o In order to properly assess cheese, conditions must be ideal:
 Proper lighting, ventilation, temperature
 Proper handling practices
 Proper sanitation practices
 Tools & Equipment, i.e. triers, knives, Natamycin spray to prevent mold growth
 An understanding of the standards by cheese type in order to determine positive qualities and defects

– REVIEW: Defects by Family
o Desireable Traits: Aroma & Flavor, Texture, Appearance
o Defects: Aroma & Flavor, Texture, Appearance

– Origin of Defects
o Milk
 Composition: Chemical properties of milk used for cheesemaking; can change with seasonality, breed
 Quality: Animal feed, dairy farm and environment, packaging (i.e. cardboard taste from packaging containers)
o Production
 Improper Moisture Content (too little syneresis, not enough heat, not enough stirring, not enough pressing)
 Improper Acid Development (excess acid -> too short texture or not enough curd knitting; too little acid -> flabby flavor, potential pathogen growth)
 Calcium Phosphate (too little “glue” can keep curds from knitting and forming a strong protein-fat structure)
 Proteolysis & Lipolysis (too little or too much can cause lack of flavor or textural development, or excessive flavor and overripening)
 Microbiological Contaminations (growth of gas formers, pathogens and indicator organisms can create mechanical openings, blowing, improper eye development; yeasts and molds can grow on the wrong type of cheese and create flavor and odor defects)
o Distribution & Storage
 Shipping (without proper refrigeration or packaging, cheese can develop defects at final destination)
 Packaging (too little packaging can cause textural issues, and foreign materials can create hazards)
 Storage (improper refrigeration can create textural and flavor defects; squishing or contamination can happen at any point in the chain)