Sensory Evaluation and Product Development What is Sensory Evaluation? • The assessment of all of the qualities of a food item as perceived by the human senses. • IFT defines sensory evaluation as: • The scientific discipline used to evoke measure, analyze, and interpret human reactions to those characteristics of foods and beverages as they are perceived by the senses of sight, smell, taste, touch, and hearing. How is Sensory Evaluation Used? • In a food company, sensory scientists work closely with product developer’s to understand: • What consumers like and why. • If consumers can tell a difference when they change a product. • In academia, sensory scientists: • Try to understand how our senses work and how our senses respond to stimuli (both from food and chemicals). • Improve testing methodology. Why is Sensory Evaluation Used? • It reduces uncertainty and risks in decision making. • It ensures a cost-efficient delivery of new products with high consumer acceptability. • Human observers are good measuring instruments. • People can sometimes detect odorants at levels lower than what can be detected by an instrument. • Instruments can not measure liking. How Does Taste Work? • There are five basic tastes: • Sweet • Sour • Salty • Bitter • Umami • The Japanese word “umami" translates as "pleasant to the taste, agreeable, good, mild, savory, delicious."
• Sources of the taste include MSG, broth, and shiitake mushrooms.
Two Types of Sensory Panels • Trained Panels • Trained = one or more sessions • Expert = months of training • Objective: can determine differences or describe a product • Untrained/Consumer Panels • Determine preference, like/dislike, and can rank in order of preference Principles of Good Practice • Facilities should be well designed • White or off-white color • Lighting should be controlled • There should be good ventilation • Samples should be prepared properly • Temperature should be controlled and the same for all samples • Volume served should be equal for all samples • Samples should be served at equivalent shelf-life or time since • Samples should be labeled with random3-digit codes to avoid bias • Excuse panelists with: • Fever or common cold, skin or nervous system disorders • Poor dental hygiene or gingivitis
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• Emotional upset or work stress- they need to be able to concentrate 30-60 min limit on smoking 60 min no coffee Do not eat w/in 2 hrs of taste – • 10 a.m. - noon optimal time for test When most awake and mental powers are peaked
Sensory Evaluation Methods • Goal is to match the right test with the right question Question
Method
Are products different?
Discrimination Tests
If products are different, how are they different?
Descriptive Analysis
What is the acceptability of a product? Is one product preferred over another?
Affective/Hedonic Tests
Discrimination Tests • Basic Question: Are two products different from one another • Basic Setup • 25-50 panelists • Screened for acuity • Given triangle, duo-trio or paired comparison tests • Analysis is done using tables which compare results to chance – this analysis ensures that the difference was real and not because people chose the correct sample by luck/chance • Advantage • Quick and simple • Limitations • Limited results – only ‘yes they are different’ or ‘no they are not’
• EXAMPLE: Are two products different from one another? • Triangle Test: Choose the sample that is most different
• Duo-trio Test: Choose the sample that matches the reference • Paired
Comparison Test: Which sample is sweeter?
Descriptive Tests • Basic Question: How do products differ in all sensory attributes • Basic Setup • 8-12 panelists • Screened for acuity • Trained • Asked to rate intensity for all sensory attributes • Advantages • Detailed quantitative information • Limitations • Time consuming
Descriptive Tests
• Most food companies have a panel that is trained on each of their products • To train a panel takes several weeks to months • What does trained mean? • It means that the panelists are trained to evaluate products similar to how any instrument would give a reading • For example, a trained panel would be a given a sample of grape juice and would be able to rate the level of turbidity, color, viscosity, etc.. • Mean attribute ratings are calculated, statistics is used to determine if the means are significantly different
Affective Tests • Consumer Acceptance Tests • Basic Question: Are the products liked? • Basic Setup • 75-150 consumers per test • Screened for product use (Do they buy the product? And how often?) • Asked degree of liking (how much do they like it) and/or preference questions • Advantages • Provides essential information – Do they like it or not? • Disadvantages • May be difficult to get a representative sample of consumers
• Acceptance Tests • Used to measure how much people like a product
• There are several types of scales that can be used (9-Point Hedonic Scale Most Common)
• Preference Tests • The “Pepsi Challenge” type of test that is widely used in marketing research • Used to determine which product is preferred although people have the option to choose “no preference”
Role of Sensory in Product Development • Reduces risk in decisions about product development • Helps to meet consumer needs and demands • Useful in determining whether a product meets consumer expectations and if there is a potential for a product in the market place Types of New Products
Almost 105,000 new food and drink products were launched globally in 2006 (Rowan 2007) • That’s around 300 for every day of the year! • It is estimated that only around 30,000 – 50,000 will succeed (Brody and Lord 2000) • There are several general categories of new products • Completely new • Line extensions of current products • Same product but repositional • Improvements of current products The Product Development Team
The Product Development Process • In general, there are three phases of product development • Phase I: Product Definition • Phase II: Product Implementation • Phase III: Product Introduction Phase I: Product Definition • Strategic Plan • Identifies company’s current market position
• Identifies company’s desired/future market position • The strategic plan will help determine if the new product should be for an existing brand or an entirely new brand • For example, a company that is a leader in snack foods through its strategic plan may decide it wants to be a leader in snack foods AND beverages – so they will decide they need to develop (or purchase) a new beverage brand • Market Opportunity Assessment • This is used to determine what products are already in the market and where there is room for new products • For example, in the sample market on the right there are no carbonated 100% fruit juices – this presents an opportunity to a company that wants to enter the beverage market
• Product Definition • The product definition integrates many objectives to ensure that the final product is successful and meets the companies strategic plan • The product definition helps guide the product development team when choosing ingredients, processing, packaging, etc. • For example based on trends and demographic information, besides being a carbonated beverage with fruit juice, the marketing team might want the product should be:
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Natural For Tweens Contain exotic flavors Shelf-stable Etc.
Phase II: Product Implementation • Prototype Development • After the concept has been narrowed down, a product development scientist will work in the lab to develop one or more prototypes • The scientist will usually set up an experimental design to vary ingredients at defined intervals to see their effect on overall liking, flavor, texture, and color • Team Input • Consumer Testing • Once the product development scientist has refined their prototypes they will work with a sensory scientist to test them with consumers • Statistics is used to determine the optimal formula • Prototype Modifications • Based on the results of the consumer testing the product development scientist may need to refine their formula (make it sweeter or less sweet, change the flavor, etc.) • Depending on the size of the change, the product may need to be consumer tested again • When choosing the final formulation other considerations will be taken into account such as cost and feasibility • Scale-up and Trial • Once a final formula has been chosen, the product development scientist will need to go to the plant and “scale-up” the formula
• This means they will take the formula from the bench top (small batch process that makes a few servings) to the plant (large batch process that makes thousands of servings) • The product development scientist will be sure it runs properly on the equipment and that the processing parameters are correct (e.g. was the mixing time sufficient to properly mix all of the ingredients?) • Before being able to commercialize (send to market) the idea, several other activities need to occur: • The package needs to be developed • The nutrition information needs to be calculated • The label needs to be created • The product must meet regulatory approval • The shelf-life needs to be tested • Marketing needs to approve the product • Supply chain needs to be notified to order the ingredients • The new formula needs to be added to the schedule at the plant… Phase III: Product Introduction • Now the product is ready to be launched! • The product development scientist will need to oversee the first production run to be sure everything goes as planned • Product support will need to be in place to receive feedback from the plant about how the product is running and from consumers to know if they are satisfied Nationwide Launch • Can cost upwards of $25 million • Only 1-2% chance of success • Success measured by product life cycle • Launch of a new product, its length of time spent as a good selling item, the time required for sales to decrease, and its eventual removal from the market. • (ie) corn flakes