PPT On SENSORY TESTING

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SENSORY TESTING Presentation Transcript:
1.2.0 The stage in Food Product Development:
Idea Stage
Development Stage
Sensory Evaluation Stage
Consumer Sampling Stage
Shelf-life Stage
Packaging Stage
Market testing Stage
Commercialization Stage

2.PREPARATION FOR SENSORY TESTING

3.TESTING AREA
Special – minimized distraction
Quiet, comfortable environment
Air-conditioned, control humidity
Location – somewhere accessible by panels
Preparation area – no entry for panelist
Might gain info that would influence their judgement
Foreign odours and odours from food preparation –eliminate (including smoking)

4.TESTING SETUP
Panelists – independent judgements
Use individual booth (no communications)
Put partitions
Construct booths along the wall that divides room
Communication panelist –operator
Switch as a signal, bell, domed hatch, etc
Booths
Sink and tap built into each booth, for rinsing
May cause odour problem (recommend suction type)
Colour – off white, light gray (not influence judgement)
Descriptive analysis and panel training session
Round table – permits discussion and passing of standards

5.LIGHTING
Uniform
Not influence the appearance of product to be tested
If colour/appearance to be judged
Choose light carefully
Fluorescent light distort colour
If eliminate color differences –
Coloured lights are used (eg- red)
Still have intensity differences
Dimmed lights

6.TESTING SCHEDULE
Time of day influence results
Lunch – better results but may not be accurate (hungry)
Best time –
Late morning and midafternoon

7.PREPARING OF SAMPLE
Well equipped kitchen
Good ventilation system for removal of cooking odour
Sufficient counter space – serving and assembling samples for presentations
Food – normal state
Preparation fully depend on the sample

8.DILUTION AND CARRIERS
Most foods served – normally consumed
Dilution – hot sauces and spices
Bland white sauce, sugar syrup
Effect should be considered
Hydrocolloid gels – taste masking effect
Carriers
Not necessary – whipping cream, cheese spread, ketchup
Use of carriers – crackers for jam, sausage for ketchup, adds cost and efforts, difficult to select appropriate carrier
Carriers – source of experimental error –
Proportion of product to carrier may not be constant
Carrier –quality unconsistent
Nature of product – necessitate that it be tested with carrier
Eg – pie filling, pastry/ icing,cake/ etc

9.SERVING TEMPERATURE
Serve at temperature normally consumed
Discriminate test – better if slightly warmer/cooler. Eg – edible oil (44ºC)
Serving temperature:
Hot foods – 60 -66ºC
Ice cream - -1 to 2ºC
Methods of controlling temperature
Warming ovens with controlled temperature and humidity
Electrically heated beakers
Blocks of styrofoam – cut out to hold containers, help maintain temperature

10.UTENSILS
Serving utensils –
not impart any taste, odour
Identical containers – minimize bias
Colourless/white container
Disposable dishes
Odour testing – stemmed wine glasses

11.QUANTITY  OF SAMPLE
Discrimination test – 16ml liquid, 28g solid
Preference test – double the amount
Amount should be constant throughout test
Why quantity important?
Enough to taste back and forth, and decide
Spices – controlled quantity
Cheese bitterness – use quinine sulfate

12.NUMBER OF SAMPLES
Determined during preliminary testing
Things to consider when deciding numbers:
Type of product
Experience of judges
Motivation
Panelists lose desire first before lose their capability

13.CODING AND ORDER OF PRESENTATION
Presentation of sample of good quality just begore one of poor quality – second becomes lower than normal
Important to randomized/balanced – small number of samples and panelist, the order can be balanced so that every possible order occurs an equal number of time

14.RINSING
Provide an agent for oral rinsing between samples
Taste neutral water is preferred
Fatty food – warm water (more effective)
Removal of flavours – crackers, apples, celery and bread
Trained cheddar cheese panelist – rinse and wait for 5 minutes before another sample

15.INFORMATION ABOUT SAMPLE
Give as little info to panelist about sample
May influence result
Eg –tomato juice was told to be high quality, ratings were higher
This preconceived impression – expectation error
Person who are directly involved with the experiment should not be included on the panel