Evaluation experience and sensory evaluation method of food aroma products

The application effect of flavors requires scientific, reasonable and accurate evaluation methods. It is necessary to standardize the descriptive terms of flavors. At the same time, it is necessary to carry out systematic training for the sensory evaluation team. In addition, it is necessary to establish scientific and reasonable evaluation methods and evaluation forms. Next This paper briefly introduces the flavor evaluation method, and takes the sensory evaluation method of meat flavor as an example to talk about flavor evaluation.

01. Specification for descriptive terminology of fragrance
Top fragrance. The aroma characteristics that people can smell first are usually composed of spices with better aroma diffusion, which are formed by the volatilization of substances with lower boiling points in the essence. The top fragrance requires a soft, elegant and distinctive aroma. Body scent. It is mainly aroma, which can be felt immediately after the top fragrance, and the main aroma of the essence volatile from various fragrance components. Body fragrance requires consistency and stability over a long period of time, and body fragrance requires richness and mellowness. base incense. After the top fragrance and body fragrance of the essence are exerted, the final fragrance left behind is composed of fragrances with large molecular weight, high boiling point and low volatility.

Fragrance requires no distortion and has a certain fragrance time. Taking meat flavor as an example, the words describing aroma similarity include aroma simulation, meat aroma, chicken fat aroma, fresh corn, roasted corn, inconspicuous meat taste, etc.; the words describing aroma preference include light, strong, fresh, Mature, prominent fatty aroma, etc.; Words describing the softness of aroma include softness, roundness, full meaty, coherent aroma, etc.; Words describing aroma intensity include direct aroma, long-lasting aroma, rich broth, etc.; The sense of soup, aftertaste and aftertaste is long and lasting, with bad smell, bad smell, sour taste, corruption and so on.

02. Evaluation methods of fragrances in different forms
1. Liquid flavor (water-soluble, oil-soluble)

Method 1: Use an electronic nose to seal the sample to be tested to measure its stability.

Method 2: Dip a small amount of essence with scented paper, first smell the top fragrance of the essence, smell the body fragrance of the essence after 10 minutes, and smell the bottom fragrance of the essence after 40 minutes. Based on personal experience and comprehensive evaluation, the students will be graded one by one, out of 10 points.

2. Paste flavor

Method 1: Use an electronic nose to seal the sample to be tested to measure its stability.

Method 2: For the paste flavor, the evaluation is mainly carried out in two aspects: smell and taste. The specific method is as follows: configure the flavor to be evaluated into a 100 ℃ boiling water solution (salt (w/w) 1.5%; sugar (w/w) 1.8%) to 0.5%. 2% solution, smell the aroma first, and evaluate its taste through the following aspects.

1. The overall feeling of taste when entering;

2. Persistence in the mouth;

3. The aftertaste left in the mouth after swallowing.

Here are some more specific methods:

(1) Fruit essence: add 0.05% essence in sugar and acid water, stir well and taste. Sugar and acid water contains 5~10% white sugar and 0.03~0.05% anhydrous citric acid.

(2) Low-acidity fruit flavors (such as bananas, strawberries, etc.) and spice types (vanilla, meatloaf, cinnamon, etc.): add 0.05% flavorings to the sugar water and stir evenly to taste. Sugar water contains 5~10% white sugar.

(3) Brown chocolate, vanilla, coffee, etc.: add 0.05% essence in sweet milk, stir well and taste. The milk solution contains 5~10% white sugar.

(4) Sweet flavor: 10% sugar, 0.1% citric acid

(5) Salty flavor: 0.2% flavor is added to 0.5% salt water to taste. For more complete tasting, add 0.2% MSG plus 0.02% I+G plus 0.1% maltodextrin.

Method 3: The method of evaluating the taste of the flavor by adding the flavor to the product. Taking meat flavor as an example, the recipe for meat products is as follows. Pork (chicken breast) 30%, salt 1. 5%, sugar 1. 8%, monosodium glutamate 0. 3%, carrageenan 0. 3%, phosphate 0. 5%, protein powder 4%, starch 10%, flavor to be tested 0. 3%, water 51. 3%. Make it into meatballs or brine square legs for evaluation.

(3) Powder flavor

For powder flavors, the evaluation is mainly based on the mouthfeel. The specific method is the same as the evaluation method 2 and method 3 of the paste flavor.

03. Notes on flavor review
1. Shake the liquid flavor and paste flavor well before the evaluation to prevent precipitation.

2. The fragrance to be reviewed should be placed in a cool and dark place before the review. After opening the package, it should be used as soon as possible. If the fragrance is not used up, if it is a liquid or paste fragrance, the cap must be tightly sealed after each use; if it is a powder Flavor, the bag mouth should be sealed to prevent loss of aroma, moisture absorption or deterioration.

04. Sensory evaluation method of meat flavor
The sensory properties of meat flavors

The sensory properties of meat flavor are a complex effect, mainly including the basic taste, aroma, taste, chemical sensory factors and other characteristics of the flavor.

The basic tastes include sour, sweet, bitter, salty, and umami, among which umami is a complex comprehensive taste that can enhance the meaty, taste, mildness, and persistence of food. Meat flavor requires no sour and bitter taste, low sweetness, and moderate fresh and salty taste.

The aroma is that the aroma of meat essence is composed of a variety of fragrant volatile substances. The aroma characteristics include the aroma of braised meat, barbecued meat, oily oil, and sauced meat, etc. It should have the following characteristics:

① Straight-forward feeling: that is, the aroma is punching the nose, which is derived from the strong smell of low boiling point and volatile spices;

② Imitation sense: the flavor should be the same or similar to the aroma of cooked meat that ordinary people eat in daily life;

③ Roundness: that is, the aroma is natural and soft, derived from amino acids, polypeptides, reducing sugars and fats, etc., and the special meat-derived aroma obtained by Maillard reaction;

Taste: The most important sensory characteristic of meat flavor is to have full meat flavor, good persistence, and long aftertaste.

Chemical sensory factors: chemical sensory factors are the feelings caused by some chemical substances in the essence, such as astringency, spicy, thorn, etc.

2. Types of Sensory Evaluation Methods
1. The two-point identification method selects the one corresponding to a certain special performance from the given two flavor samples A and B. For example, change the amount of MSG and choose the fresher one among the two flavor samples.

2. The two-point hobby method compares the two samples A and B to determine which one is better.

3. The three-point comparison method divides the two flavor samples of A and B into a group of three points such as (A, A, B) or (A, B, B), and selects the point that feels different among the three points, which can reduce the Errors caused by inaccurate judgment.

4. The three-point hobby method compares the selected one with the other two on the basis of the three-point comparison method, and selects the favorite one.

5. In the 1:2 point comparison method, firstly give A or B as the standard sample to the quality inspector, after fully memorizing its characteristics, then give A and B two kinds of samples at the same time, and choose the same one as the standard sample. kind. This method is generally used for production control.

6. The sequential method is a method of giving A, B, C, ... n flavor samples, and then recording them in order according to the strength of the flavor or the degree of preference.

7. Selection method: The method of selecting the best sample from samples A, B, C...M, and the number of samples must be more than 3.

8. Spousal method Given two groups of the same flavor samples A, B, C...

9. One pair comparison method When evaluating A, B, C... combination, and then select samples with a strong characteristic or preference from each group.

10. Scoring method The quality of the given flavor samples is evaluated on a numerical scale of 1 to 100 points, 1 to 10 points or -5 to 5 points.

11. Separate description and scoring method Comprehensively consider all the characteristics of meat flavor, such as aroma characteristics, strength, taste, and aftertaste, describe the characteristics and score them separately. Using this method can give a more comprehensive evaluation of the fragrance, which is generally carried out by professionals. The description content of meat flavor generally includes characteristic aroma, aroma simulation degree, meat taste, fat aroma, soup sense, etc.

Selection of Sensory Evaluation Method In the sensory evaluation of meat flavors, it is very important to select an appropriate method according to the purpose of use when performing a certain evaluation. Sensory evaluation methods are divided into the following four categories according to different purposes:

3. Sensory evaluation method
1. Methods of identifying differences: (1) Two-point identification method; (2) Two-point preference method; (3) Three-point comparison method; (4) Three-point preference method; (5) 1:2 point comparison method; ( 6) Spouse law; (7) Choice law.

Objectives: Trial-production improvement research, quality management, judgment of evaluator ability, judgment of quality of samples, determination of stimulus threshold and discrimination threshold.

2. Methods of determining the order: (1) sequential method; (2) general comparison method.

Objective: Trial-production improvement research, judgment of quality of samples, hobby investigation, judgment of hobby tendency, evaluation of evaluator's ability.

3. The method of evaluating quality: scoring method.

Purpose: trial production improvement research, quality expression, quality control, hobby survey.

4. Comprehensive evaluation method of characteristics: describe the scoring method separately.

Purpose: trial production of new products, improvement of flavor, comprehensive evaluation of products, training of evaluators.

4. Problems existing in sensory evaluation
Problems that should be paid attention to in sensory evaluation The problems often encountered in the sensory evaluation of meat flavors include fatigue effect, sequence effect, mark effect, position effect, contrast effect and tone change effect, etc., which all affect the sensory evaluation to a certain extent. Therefore, in order for sensory evaluation to be authentic and credible, these problems should be paid attention to and avoided.

Fatigue effect: refers to the phenomenon that if a stimulus continues for a long time, the sense of taste and smell will be weakened, resulting in loss of consciousness.

Order effect: The tendency to overvalue the stimulus that comes first or the stimulus that follows.

Marking effect: not related to the nature of the sample, but a tendency to influence judgment due to preference for sample markings. There are two types of marker effects: the common tendency of the majority and the subjective tendency of the individual. It is based on your name or capital letters of your unit and memory of personal experience.

Position effect: In the three-point test method or the five-point test method, there is a tendency for the test to have a particularly high number of choices when placed in a specific position that is not related to the quality of the sample.

Contrast effect: In taste, the first taste makes the second taste stronger or weaker.

Tone-shifting effect: the phenomenon in which the flavor of the flavor that is tasted first changes the flavor of the flavor that is tasted later.

V. Solutions to Sensory Evaluation Problems
In order to ensure the validity of the statistical analysis of sensory evaluation and reduce the adverse effects of these effects, the following items must be paid attention to in the sensory evaluation of meat flavors, namely:

(1) Select healthy people who feel normal to participate in the evaluation, and there are generally no less than 5 to 7 evaluators with certain experience;

(2) There should be a good evaluation environment, and the evaluation room should be quiet, well-lit, and free of peculiar smell. Before the evaluation, the host should explain the relevant requirements to the evaluators. During the evaluation, the evaluators should make independent judgments and not discuss with each other to avoid mutual interference.

(3) The prepared flavor samples are placed in the same container, and the number and location of the samples should be as consistent as possible.

(4) The number of samples to be evaluated at one time should not be too many, especially since meat flavors generally need to be evaluated for taste, it is easier to produce taste fatigue. The pairing method generally does not exceed 5 pairs, and the ranking method and the scoring method are preferably less than 7.

(5) Rinse the mouth after each tasting of a sample to remove residual irritation before proceeding to the next tasting. In addition, the sample code and location have a non-negligible impact on the actual evaluation results.

As an objective image, the position effect can be overcome in three ways:

(1) Evaluators should strive to improve their evaluation skills, including sensitivity and judgment.

(2) Use sequence neutral word coding (such as Chuan, Ge, Gan, Men, Gong, etc.).

(3) All samples are rotated at one time, the samples are placed in a circle, and the tasting order is random. After tasting, the data can be obtained by the pan-ratio method and the pairwise comparison method. The pan-ratio method refers to tasting all the samples generally (or tasting individual samples repeatedly) and scoring them respectively. The pair-wise comparison method is to compile all the samples participating in the evaluation into all combinations of two pairs, and the evaluators will taste them one by one without scoring. Can.

Source: Xiaoyan walking on the road of research coffee, please indicate the source when reprinting.