Dr Kedibone Modika and Tebogo Pitse, agricultural economists on the Agricultural Analysis Council, have a look at how the flavor, color and tenderness of pork trade all the way through the freezing and thawing procedure.
Meat consists of about 60% to 70% of naturally happening water. This makes meat and its merchandise extra liable to microbial spoilage and chemical reactions that may negatively have an effect on high quality traits reminiscent of color, texture and flavour.
Freezing meat is due to this fact an effective way to keep its dietary price and stay it from spoiling via principally decreasing the velocity of microbial spoilage and deterioration.
Relying at the lower, form of meat and packaging, raw meats could also be preserved within the freezer and stay at a top quality for anyplace from one to twelve months.
the benefits of freezing meat
Meals protection
Freezing has been confirmed to lower probably damaging micro organism, which will also be the supply of meals poisoning. So long as meat is saved in an acceptable approach and correct instructions are adopted for thawing and cooking, frozen meat may be very secure.
The few outbreaks of foodborne sicknesses related to frozen meat and different meals point out that some, however no longer all, human pathogens are killed via the freezing procedure.
Advanced meat texture
It can be interesting to meat fanatics to buy a steak from the store and cook dinner it instantly. Then again, analysis has proven that freezing the steak and cooking it later if truth be told improves the tenderness of positive cuts.
Freezing has been proven to motive muscle fibres to swell and rupture, leading to advanced tenderness. To end up this, the Agricultural Analysis Council’s (ARC) meat science group assessed loin steaks for tenderness the usage of the Warner-Bratzler (WB) shear pressure check, which measures the pressure had to shear the beef.
The steaks have been elderly for 3, six and 9 days previous to freezing. The steaks have been then thawed and cooked sooner than the check. Contemporary steaks have been cooked instantly after garage/getting old and examined. The effects confirmed the steaks that have been frozen-thawed previous to cooking have been extra comfortable (decrease WB) than the contemporary steaks (see Graph 1). As well as, prolonged getting old sessions coupled with freezing are extra beneficial to meat tenderness.
Disadvantages of freezing meat
Greater meat discoloration
Everyone knows that color is frequently seen as the #1 issue utilized by customers when buying pork, rather then value. Shoppers most often keep away from meat that has discoloured and search for a ravishing, vivid cherry-red color when purchasing meat. Subsequently, keeping up a vivid cherry-red color is a commonplace fear for the beef trade in attracting customers.
Frozen thawed meat loses this vivid cherry-red color all the way through thawing. That is because of the leaching of myoglobin exudate of meat all the way through thawing. (Myoglobin is a protein that provides meat its color.) It has additionally been proven that myoglobin loses its herbal qualities all the way through freezing and thawing, which is to present meat its vivid, cherry-red color.
There could also be accumulation of metmyoglobin, which provides meat a brownish color. Myoglobin and metmyoglobin concentrations have been measured the usage of a Minolta color meter.
Frozen-thawed meat has an excessively top focus of metmyoglobin and a low focus of myoglobin, and this worsens as the beef is saved/elderly for prolonged sessions sooner than freezing. Metmyoglobin is the reason for the feature brown colouration that most often seems at the floor of the beef.
Greater drip/purge
Drip loss is an important meat high quality feature within the meat trade. It’s the fluid this is misplaced from meat all the way through thawing. When meat is frozen, ice crystals are shaped throughout the construction of the beef, and those crystals rupture the fibres and fluid drips out all the way through defrosting.
The reddish fluid that seeps out all the way through defrosting incorporates water, iron and proteins from the beef. The fluid loss frequently reasons dehydration and nutrient loss in frozen meat. This may make frozen-thawed meat drier than contemporary meat, relying at the length and means of freezing.
This side is economically adverse because of loss yield (weight) and lack of soluble vitamins. It additionally reasons the beef to have an unattractive look. Frozen-thawed meat has as regards to 6% drip loss when compared with contemporary meat’s 2,4% after the beef has been saved for 3 days (see Graph 2).
Significance of right kind labelling
Even if frozen-thawed meat has the benefit of being extra comfortable than contemporary meat, different high quality traits reminiscent of color, drip loss and flavour are compromised, as defined above.
Subsequently, labelling is vital to tell the shopper that they’re purchasing meat with some compromised high quality traits. Medical research have confirmed that buyers are ready to pay additional for superior-quality meat merchandise with assured tenderness at the side of leanness, juiciness and flavour.
Consistent with the Executive Gazette of 21 April 2023, foodstuffs that have been frozen and thawed for next sale should no longer be labelled contemporary. Those foodstuffs should point out ‘in the past frozen’ at the package deal.
To authenticate that this meat labelling law is adhered to, the ARC’s meat science group has installed position a technique that may distinguish the variations between contemporary and frozen-thawed meat.
This technique makes use of a proteomics option to assess proteins which can be denatured (proteins that experience their feature houses destroyed) via freezing. Initial effects have proven that the protein myoglobin, which contributes to the cherry-red color, was once noticed to lower in frozen-thawed meat when compared with contemporary meat.
This displays that this protein is misplaced all the way through defrosting. Subsequently, via labelling, customers will make an educated selection.
The perspectives expressed in our weekly opinion piece don’t essentially replicate the ones of Farmer’s Weekly.
E mail Dr Kedibone Modika at [email protected].