The Meat We Eat is a course designed to create a more informed consumer about the quality, safety, healthfulness and sustainability of muscle foods and address current issues in animal agriculture in developed and developing countries.
Packaging
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The Meat We Eat
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Week 4
This week we'll learn about meat quality, fabrication, and packaging.
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Chad Carr, Ph.D.
[BLANK_AUDIO]
Hello friends, and welcome back to this, our fifth week of The Meat We Eat.
Today we're going to discuss packaging.
Predominantly, we'll concentrate on fresh meat packaging technology
that we utilize here in the US and internationally.
As we think about packaging fresh red meat, the thing that is the most important
to a consumer's perception and their ultimate buying,
of this product at retail, is its color.
That is the most important parameter, and so, as
we look here, as the color as it associates with
the appearance of the product, how it kind of ties
in with the odor of the product possibly at retail.
All of those things certainly do serve as an indication of spoilage, but, as
a whole, there's some things that we do relative to packaging that are, we could
have two products that are exactly comparable
in terms of their level of spoilage, bacterial
growth, and we can still yet have
some differences in terms of color and perception.
So, collectively, consumers, they associate color with freshness.
All right.
That is the, the key take home parameter here.
So if we think about how fresh meat is generally marketed at
retail, particularly in this country, we'll
concentrate on these different kinds of packaging
methods, kind of hit on some of the positives and negatives that they
offer relative to shelf life and consumer buying experiences as a whole, okay?
So, in many full service retail grocers here in the U.S., there's
kind of been a, a renaissance if you will to, to have full service.
Okay?
And so with that, if we're going to have a full
service meat case, most likely, those cuts that if we come up
and we say, I want that steak, and I want a little,
package of ground beef from over in this area of the case.
Those products as they're drawn out by some worker at
our retail establishment, that'll probably be wrapped in butcher paper, okay?
And so, collectively, as we think about this product that we have
purchased from a full service case, I like it because it gives
me the feeling that certainly, I mean, we're, we're having some report
here with someone who has some knowledge about the product that they're selling.
There's some excellent customer service there you would hope.
So there's a good feeling associated with buying this product, and it kind of
gives you an old school butcher shop feel just like the slide says there.
But, likely, most of the butcher paper
that would be utilized, let's say at retail,
probably, and I mean we could have some
higher quality butcher paper be utilized, but, for
the most part, it might be line, unlined or thinly lined, and so it probably
won't be, offer exceptional shelf life either within
the refrigerator or frozen shelf life either, okay?
So, this certainly is how meat retail products were
marketed in this country for, for quite a long time.
With full services cases, and as I've
stated, there's been some renaissance with that.
Okay?
So, then, as we further think about re,
retail meat marketing, for years and years, and still
honestly probably the predominant method, a fresh retail meat
marketing would be utilization of polyvinyl chloride overwrap.
And so with that, we would have fresh meat that would be placed in a Styrofoam
tray, and then it would be overwrapped with an oxygen permeable PVC film.
And so, I haven't mentioned this yet, but, as we think back to what we said
was important to consumers relative to retail meat
purchasing decisions for fresh meat products, color is everything.
Oxygen is both the friend and enemy of fresh meat color at retail.
It is.
So we'll talk about how that works in just a second, but like it states here on
the slide, a huge positive in terms of
utilizing PVC overwrap is that it is oxygen permeable.
It allows fresh meat like we see in this
picture her to have an oxygenated red desirable oxymioglobin pigment.
Okay?
Which is very desirable.
But, with time, we will see that color start to change as that myoglobin
compound, as it oxidizes with continued exposure to oxygen.
So, that, as we talk about color, we'll hit on it more here in just a little bit.
Other positive and negatives that we would have of
utilizing a PVC tray is just like it states.
We have something that's pretty big, and we've got it in this PVC tray.
Tray could be kind of flimsy, and it could lead to some purge
drip if we've not done a very good job securing the PVC
overwrap around our tray, but it does prevent surface dehydration just like
it states, but that's just probably not real much shelf life impact there.
Just kind of prevents some dehydration, all right?
So, this is utilized very extensively within the U.S., all right?
To kind of get at what we were talking about relative
to color, we can see this document or this figure here.
So when we cut steaks off an intact roast,
initially, those stakes would look like we see here.
It would be the oxymyoglobin.
All right.
It is yet to be oxygen aided, and it would look purple in color.
Okay, with time, with exposure to oxygen, it
will be oxygenated, and then we have a, with
that time, that product will bloom, is what's
called an industry, and it will become oxymyoglobin, okay?
Then as we continue to have this product, and it is
continually exposed to oxygen, it will oxidize, will have a change in
its iron status and will go from oxymyoglobin to metmyoglobin, which
is assumes this brown color that we see here in the corner.
So to kind of have a quick recap of what happens here.
If we have a roast, we cut a steak
off that roast that was just previously attached to
this roast, we roll it over, initially, the product
would look like you see there in the top corner.
With, it would look purple, and that would be deoxymyoglobin.
It has yet to be oxygenated.
When it's exposed to oxygen, it blooms, it oxygenates, it becomes red.
And then in the corner, would be with continued
exposure to oxygen, it will change from that bright, youthful,
cherry red to what we see with the brown
color in the corner, which is not desirable to consumers.
As we think about this concept that we talked about
on our first slide here, talking about how important color is
to consumers' perception of red meat at retail, it really
is the driving force of this slide that we have here.
So, some 30 years ago, 40 years ago, packers and retail
retailers in this country, they said, man, all we need to do, if
we just market retail red meat as vacuum sealed, then we have
really extended the shelf life of these products, and it does.
So, as we look at this picture here, if we take wholesale cuts, which we
do extensively, and we evacuate those products, we
have a barrier film for this plastic bag.
We evacuate the atmosphere, pull a vacuum, seal the product, that product
has exceptionally good shelf life, really, really good shelf life.
It can last a long time, all right?
If we took and we cut steaks out of these roasts, for instance, those
steaks would have exceptionally good shelf life, both fresh and frozen.
So that's an excellent situation for retailers in terms
of reducing their costs and maximizing all the value from
the products that they purchased, and consumers, in terms of
satisfaction at home, but there's one big problem with that.
When we vacuum seal this product, if we
think back to our previous slide, we discuss color.
When we vacuum seal this product, those species, which have more
myoglobin like beef and lamb, that product, it will lose its oxygenation.
Or if we never, if it's never been oxygenated, if
we have an entire intact muscle, the inside of it.
When we evacuate oxygen, then that product, it will look purple.
If we have retail steaks that are cut, and then we evacuate
the oxygen, and we vacuum seal it, they'll look purple on the surface.
Consumers, they don't know what that is.
They think that the product's unwholesome, or it's not fresh, and so retail
meat marketing of vacuum sealed products has been very marginal at best.
And so, with what the, the retail
meat industry and commercial meat packers in this
country decided upon is that we need to kind of meet in the middle here somewhere.
Okay?
With vacuum sealed products, we have exceptionally
good shelf life, but consumers won't buy.
Products that are offered in PVC overwrap, they
look desirable, youthful, wholesome and fresh, but those products,
they have a very, very short shelf life
due to the exposure to oxygen that they have.
So within the past 15 years, packers
and retailers, particularly our large integrated retailers that
we have in this country and internationally,
they've gotten with our major red meat processors
and poultry processors and say, okay, let's add a component to what we do in
terms of fabrication within our processing facilities,
and go ahead and have case ready packaging
via a modified atmosphere packaging system.
So how that works would be these two examples that we see here in this picture.
So let's say under USDA FSIS inspection, that we would have a facility
that would receive boxed beef wholesales, inside
rounds, rib eye rolls, strip loins, etcetera.
Those would come into another USDA
FSIS inspection facility, which whose predominant role
is to cut them into steaks, roasts, and to make grinds and ground beef.
All right?
With that being the case, those products then will go into retail ready
packages, possibly, like we'd see down here in this lower picture with the tray.
That's a tray flush system.
That would be one option.
So all, this would be occurring under federal inspection, and they, those
products, when they leave that facility, would leave in one of two ways.
They come in as box beef or box port,
possibly, and they would leave as retail ready packages.
Either as a tray flush system, where we put x number of products within this tray,
we evacuate the atmosphere, and then flush that with a different given atmosphere.
So that will have improved shelf life, as compared to PVC overwrap.
Or, the other option would be what you see in the corner, where we have products that
are packaged just like you would see at
many retailers in PVC overwrap, which is oxygen permeable.
But then we place those products inside a pillow pack or a
mother bag system in which we change the atmosphere in this entire bag.
And then, due to the oxygen transmission, right, of that PVC overwrap,
it allows the product to bloom and to be oxygenated at presentation at retail.
So, that’s how it works.
And just like I mentioned, either a tray flush system, we have
individual packages, we evacuate the atmosphere, we place, we replace it with
another given set of gases, or we replace the atmosphere within a
mother bag, and we get multiple retail packages out of that bag.
The gases that commonly are used in these different situations.
We'd have carbon dioxide and oxygen, a
lot of times will be used collectively together.
Or also, there's some utilization of carbon monoxide in super low levels, with
the inclusion of nitrogen as a filler gas, and that allows us to
have greatly improved shelf life that we would have as compared to conventional
PVC overwrap products due to the improved
shelf life stability utilizing those modified atmospheres.
As we think about the cascade of red meat and poultry products wh,
what would be offered for sale, collectively beef and lamb, they
would have greater shelf life, as compared to poultry, and as
a whole, whole muscle cuts will certainly have improved shelf
life, as compared to ground cuts aw increase the surface areas
through grinding.
It serves as a pro-oxidant, and it will decrease the shelf life
of ground products and variety meats due to a different fatty acid profile.
They tend to be more unsaturated collectively.
The fatty acid profile those as compared to whole
muscle cut, will have decrease shelf life as well.
So, that kind of quantifies differences between
species, and also organ meat and grinding.
So, collectively, if we want to maximize the shelf life of any
product that we're discussing here, we
want to have excellent temperature control.
And like we talked about in our previous lecture, if there are products
that are offered at a reduced price at retail due to some marginal
oxidation or metmyoglobin establishment on the surface of the product, they'd be an
awesome buy if you planned to, to go ahead and consume those pretty soon.
Okay.
So if we are going to freeze meat, let's say that we bought four
packages of pork chops and we could only eat two for this given weekend.
Things that we need to do to ensure that we'll be able to get all of
the value that we could out of these other two packages of pork chops that we
couldn't eat, before we freeze 'em, we need
to do everything that we can to evacuate
oxygen because it will really improve the frozen
shelf life of the products that we have.
So, we can either take wax paper and/or aluminum
foil and we can just cover that on our
PVC overwrap tray that we have because we do
not just want to freeze that product in PVC overwrap.
There's absolutely no barrier there whatsoever.
It'll oxidize really fast.
The best thing to do is, if we have the
ability to vacuum package those products, and if we do
that, if we've got a good seal on a correctly
vacuum packaged product, you got pretty darn long shelf life, actually.
It could, you know, I've eaten steaks that have been properly vacuum packaged that,
and frozen, they probably have been, six, seven years post-mortum and been okay.
That, that might be the exception of the rule, but,
they can certainly last a pretty extended period of time.
When we want to freeze meat from a food safety perspective,
we want to, freeze the product as rapidly as we can, allow
circulation around the product to maximize the, or minimize the amount of
time that we have prior to the for the product to freeze.
And then that way we will end up, we will cause smaller formation of ice
crystals, and it'll have less disruption of microfibrils
and will ultimately have improved palatability later on.
But do remember, just like it states here on this slide,
freezing is not a point of lethality relative to any pathogen.
It's not going to serve as a terminal end point there.
When we go to thaw these frozen products, we want to
do everything that we can to ensure that we minimize cross contamination.
So, don't thaw these products in the sink.
Ideally, what you'd like to do, is to either put them in the refrigerator
and allow them to thaw over a longer period of time, or, if you
do need to thaw the product over a shorter period of time, it's certainly
fine that they could be placed in
an area where you could minimize cross-contamination.
Run cold water over the outside of the product, and it can, it can work fine.
So, this right here is just kind of documenting, this is a USDA chart,
which documents approximate frozen shelf life of different products.
And, you can kind of see that, fresh meat, that's whole muscle, it could possible
have a pretty extended shelf life if we've got a good seal on the product.
We already mentioned some here about defrosting, but certainly,
like it's stating here, we don't want to do this
on the countertop for sure, or anywhere where we could
have cross-contamination, or we could cause cross-contamination, I could say.
Because that, like it states, will really
exacerbate microbial growth more at those advanced temperatures.
Freezing products, freeze them fast, and thawing products.
Be sure to minimize cross contamination and don't thaw them on the sink.
Okay?
Thank you all.
We'll see you later.
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