0:00:00.000,0:00:08.099
The topic of today's lecture is Contemporary development of processing of raw materials of animal origin

0:00:08.099,0:00:12.098
with emphasis on meat quality evaluation.

0:00:12.098,0:00:19.963
The lecture is part of Module 4: Precision Livestock Farming, that is a part of the ISAGREED project.

0:00:19.963,0:00:26.962
This presentation was supported by Erasmus+ KA2 Cooperation Partnerships Grant

0:00:26.962,0:00:32.294
"Innovation of the content and structure of study programmes in the field of management

0:00:32.294,0:00:36.393
of animal genetic and food resources using digitalization".

0:00:38.393,0:00:47.158
As part of the lecture, we will first clarify what we mean by the term raw material and list raw materials of animal origin.

0:00:47.158,0:00:52.590
We will talk in more detail about one of them, namely meat.

0:00:52.590,0:01:00.589
We will list the attributes of meat quality and what factors influence meat quality.

0:01:00.589,0:01:04.588
Next, we will move on to carcass evaluation

0:01:04.588,0:01:10.587
and the possibilities of evaluating meat quality using selected techniques.

0:01:11.586,0:01:16.585
Under the term raw material, we generally include any material of natural origin.

0:01:16.585,0:01:21.584
These raw materials can be obtained from animals or from plants,

0:01:21.584,0:01:30.916
or they can also be material of "non-living" origin, such as various minerals, metals, oil or coal.

0:01:31.916,0:01:39.914
Raw materials of animal origin include any material originating from or produced by animals.

0:01:39.914,0:01:46.080
It can serve directly for human nutrition, such as meat, milk, honey or eggs,

0:01:46.080,0:01:56.744
possibly for further processing and use, e.g. in the textile industry, such as wool, leather, feathers or silk.

0:01:57.744,0:02:05.809
Next, we will focus more on one of the essential products of animal origin: meat.

0:02:05.809,0:02:11.475
Meat is important in human nutrition, mainly because it is one of the main protein sources.

0:02:11.475,0:02:17.473
From the graph on the right, it can be seen that since 1960,

0:02:17.473,0:02:21.473
the global production of meat has been continuously increasing;

0:02:21.473,0:02:27.471
while in 1960, it was approximately 75 million tons per year,

0:02:27.471,0:02:34.170
today the production is many times higher and is approximately 350 million tons per year.

0:02:34.170,0:02:42.168
This rise is related to the increase in the global population but also to the improvement

0:02:42.168,0:02:45.734
of the economic situation in certain regions,

0:02:45.734,0:02:53.433
where people can afford to consume meat in larger quantities than in the past.

0:02:53.433,0:03:01.431
The improvement of the economic situation is also related to the fact, confirmed by various research,

0:03:01.431,0:03:08.430
that meat quality is the main criterion influencing consumer decisions on the market.

0:03:09.430,0:03:12.996
Meat quality is a relatively broad term.

0:03:12.996,0:03:17.595
Meat quality attributes can be divided into several categories,

0:03:17.595,0:03:26.093
including Nutritional parameters (as protein and fat content, fatty acid profile and mineral content),

0:03:26.093,0:03:36.524
sensory parameters (as texture, colour, juiciness, aroma or odour, taste and marbling),

0:03:36.524,0:03:44.023
safety parameters (as microbiological status, drug residues and heavy metal content),

0:03:44.023,0:03:54.454
technological parameters which are related to meat processing (as shear force, pH values, drip loss, fat content and water content)

0:03:54.454,0:04:01.020
and last but not least ethical aspects as sustainibility and animal welfare.

0:04:02.019,0:04:09.018
Related to this is the fact that there are really many factors, whether internal or external,

0:04:09.018,0:04:12.517
that can affect the quality of meat in some way.

0:04:12.517,0:04:21.782
Among the internal factors we can include the genetics of the animals, which is also related to their breed affiliation,

0:04:21.782,0:04:29.781
slaughter weight and status of animal which includes its age, condition and health.

0:04:29.781,0:04:37.312
There are many important external factors, as nutrition, lairage condition, climate,

0:04:37.312,0:04:45.077
animal handling, social environment, transport, pre-slaughter handling, slaughter procedure,

0:04:45.077,0:04:51.210
post-slaughter handling (e. g. ageing time) and finally culinary aspects.

0:04:51.210,0:04:58.108
One of the important parameters of meat performance evaluation is dressing percentage

0:04:58.108,0:05:05.640
which represents the percentage of a carcass weight of an animal relative to its live weight.

0:05:05.640,0:05:13.638
The shape of the carcass body depends on the technological processing and is specific depending on the species.

0:05:13.638,0:05:20.171
Average values of dressing percentage for selected categories are given in the table.

0:05:20.171,0:05:25.436
In cattle dressing percentage ranges between 50 – 60 %,

0:05:25.436,0:05:36.867
in pigs it is bit higher (between 65 – 80 %), in small ruminants on the contrary lower (about 50 %).

0:05:36.867,0:05:44.632
The highest values of dressing percentage are achieved in poultry, especially in turkey meat broilers,

0:05:44.632,0:05:48.132
where we reach values up to 85 %.

0:05:48.132,0:05:54.864
Relatively large ranges even within individual species are related to the fact

0:05:54.864,0:06:00.862
that dressing percentage always depends on the nutritional status of the slaughtered animal.

0:06:01.862,0:06:05.328
The SEUROP system is used in the European Union

0:06:05.328,0:06:11.794
to assess the quality of slaughtered animal carcasses and their subsequent monetization.

0:06:11.794,0:06:17.126
The name is derived from the designation of individual quality classes.

0:06:17.126,0:06:23.125
In the case of pigs, we distinguish a total of 6 classes according to lean meat content,

0:06:23.125,0:06:30.423
while class S is the best and includes pieces with a lean meat content at least 60 %;

0:06:30.423,0:06:39.422
on the other hand, if the carcass contains less than 40 % of lean meat, it is assigned to the worst class P.

0:06:40.421,0:06:50.419
In cattle, in addition to 6 classes according to muscle development, denoted by the letters S, E, U, R, O, P,

0:06:50.419,0:06:54.752
there are also five qualitative classes according to the fat cover,

0:06:54.752,0:07:00.751
where 1 is the best class with the minor proportion of subcutaneous fat,

0:07:00.751,0:07:09.149
and class 5, on the contrary, represents the highest fatness, which is currently undesirable,

0:07:09.149,0:07:13.981
as we do not have the same use for animal fat as it was in the past,

0:07:13.981,0:07:19.180
when animal fat was processed, e.g. for the production of soaps.

0:07:19.180,0:07:25.846
Here are presented several methods used nowadays for assessment of fat and muscle content.

0:07:25.846,0:07:33.844
It is for example  „fat o meter“, Henessy grading probe or computed tomography, but which is quite expensive.

0:07:33.844,0:07:39.410
The advantage is that it is possible to evaluate living animals.

0:07:39.410,0:07:45.109
On the processed carcass body, we distinguish parts of different values.

0:07:45.109,0:07:55.706
In general, the most valuable parts include the muscles located along the back of the animal and in its hind parts.

0:07:55.706,0:08:03.038
Depending on their characteristics, the individual parts are then suitable for various culinary treatments,

0:08:03.038,0:08:08.437
especially the length of the heat treatment – cooking or baking – needs to be adjusted.

0:08:09.437,0:08:15.436
The so-called marbling, which is determined by the content of intermuscular fat,

0:08:15.436,0:08:20.102
is very important for the taste and culinary properties of meat.

0:08:20.102,0:08:26.700
Marbling positively affects the texture, juiciness, aroma and taste of the meat.

0:08:26.700,0:08:35.099
Different scales are used to rate marbling; in general, the higher the degree of marbling, the higher the price of the meat.

0:08:35.099,0:08:42.497
The Japanese breed WAGYU is especially characterized by pronounced marbling.

0:08:42.497,0:08:51.362
In certain cases, the quality of the meat can be negatively affected by so-called technological defects.

0:08:51.362,0:08:56.161
The most common are known as DFD and PSE.

0:08:56.161,0:09:06.992
DFD means dark, firm and dry meat. It predominantly occurs in beef and lamb, sometimes also in pigs.

0:09:06.992,0:09:16.457
It is connected with long-term pre-slaughter stress (e.g. transport exhaustion) and depleted level of glycogen.

0:09:16.457,0:09:22.856
DFD meat is characterized by  high pH value and water holding capacity,

0:09:22.856,0:09:29.855
dark purple red colour, bland taste and smell undesirable for customers.

0:09:29.855,0:09:37.386
It has reduced shelf life and a greater ability to support microbial growth,

0:09:37.386,0:09:41.119
resulting in reduced storability.

0:09:41.119,0:09:47.118
On the contrary PSE meat is pale, soft and exudative.

0:09:47.118,0:09:55.816
This deffect predominantly occurs in pigs and poultry and it is usually connected with accute pre-slaughter stress.

0:09:55.816,0:10:06.981
A mutation in the ryanodine receptor (RYR1) in pigs (esp. pietrain, landrace breed),

0:10:06.981,0:10:16.245
which confers sensitivity to halothane and succinylcholine, has been identified as a major cause of PSE.

0:10:16.245,0:10:21.411
The typical characteristics of PSE meat are low pH value

0:10:21.411,0:10:32.709
shortly after slaughtering and a high temperature within muscles (above 37 °C) which leads to reduced proteolysis

0:10:32.709,0:10:40.174
and undesirable characteristics as pale colour and unability to hold its own tissue water.

0:10:42.174,0:10:47.173
There are many parameters assessed in meat quality evaluation,

0:10:47.173,0:10:56.171
including sensory attributes as colour, flavor and smell; physical attributes as water holding capacity,

0:10:56.171,0:10:59.670
intramuscular fat content (so called marbling)

0:10:59.670,0:11:06.969
and Warner-Bratzler shear force results as characteristic of meat tenderness);

0:11:07.102,0:11:15.867
microbiological characteristics as total viable content and bacterial contamination and chemical attributes

0:11:15.867,0:11:24.465
which characterize composition and nutritional content of meat as protein content, moisture and pH.

0:11:25.465,0:11:32.664
Meat quality assessment methods can generally be divided into objective and subjective ones.

0:11:32.664,0:11:37.496
Each of these groups has its advantages and disadvantages.

0:11:37.496,0:11:48.360
The advantage of objective methods, which include various laboratory tests is especially the accuracy of results,

0:11:48.360,0:11:53.693
on the contrary these methods are often cumbersome, time-consuming and expensive

0:11:53.693,0:11:56.459
(especially because special equipment is needed).

0:11:56.459,0:12:03.757
For sensory evaluation, which represents subjective methods, no special equipment is needed,

0:12:03.757,0:12:09.490
but results often depend on the experience of evaluators;

0:12:09.490,0:12:18.721
these methods have poor reliability and are difficult to quantify, which can be considered as their disadvantages.

0:12:18.721,0:12:26.053
The main techniques used nowadays for the evaluation of meat quality are spectroscopic techniques

0:12:26.053,0:12:33.052
( for example Near-Infared Spectroscopy, Raman Spectroscopy and Terahertz Spectroscopy),

0:12:33.052,0:12:40.783
Imaging Techniques (as Hyperspectral Imaging, X-ray imaging and Thermal Imaging),

0:12:40.783,0:12:50.382
Machine vision as camera shot, ultrasound imaging, nuclear magnetic resonance, computed tomography

0:12:50.382,0:12:57.680
and electronic nose based on electrochemical or piezoelectric senzors.

0:12:57.680,0:13:03.946
Electronic nose is  a technique that simulates the human olfactory system.

0:13:03.946,0:13:11.144
It is a promising technique for meat freshness detection, shows high potential in quality control.

0:13:11.144,0:13:19.009
This technique provides efficient, rapid, non-destructive, real-time, and environmentally friendly testing.

0:13:19.009,0:13:28.607
Can distinguish among microbiological, chemical, and physical contaminants in food without any sample preparation.

0:13:28.607,0:13:35.273
It is inexpensive, simple to use method with good reproducibility and repeatability.

0:13:36.272,0:13:44.271
Computer vision collects and analyzes spatial information gained from digital images of samples,

0:13:44.271,0:13:47.737
such as color, size, and surface structure.

0:13:47.737,0:13:57.168
Data analysis is composed of two main parts: image processing and image analysis.

0:13:59.168,0:14:04.534
Spectroscopy is considered one of the most promising nondestructive techniques.

0:14:04.534,0:14:10.699
It can be used for monitoring and detecting meat quality and microbial contaminations

0:14:10.699,0:14:18.697
(e.g. shear force, total viable content, intramuscular fat, total volatile basic nitrogen,

0:14:18.697,0:14:23.696
and thiobarbituric acid-reactive substances in beef;

0:14:23.696,0:14:32.361
total viable content and total volatile basic nitrogen in pork; and drip loss, moisture and water activity).

0:14:33.361,0:14:41.360
At this moment I would like to thank you for your attention. If you have any questions, you can use the e-mail listed here.