Control of Food Deterioration

Preventing Deterioration Biological (bacteria, yeast, mold, parasites)

- Apply proper heat treatment - CFR 21 (Code of Federal Regulations, FDA) sets heat treatment schedules for achieving appropriate kill levels (by order of magnitude) for key bacteria of risk in all types of products. - wet heat (steam) kills more effectively than dry heat.

Preventing Deterioration Biological (Bacteria):

- Apply proper irradiation, UV, or ozone treatment. - CFR 21 (Code of Federal Regulations, FDA) sets appropriate levels for application. - UV used to flash pasteurize juice, irradiation used on almost all spices coming into U.S. Ozone popular to kill listeria (kills cell membranes) in seafood plants.

Preventing Deterioration Biological (bacteria, yeast, mold)

- Bacteria grow at Aw > 0.850 - Yeast grow at Aw > 0.750 - Mold grow at Aw > 0.600 Control Aw by drying, salting, or adding sugar to a food.

Preventing Deterioration Physical

- Control temperature - keep refrigerated product refrigerated at appropriate temperatures; minimize free-thaw cycling of freezers ,pack frozen foods tightly and with a good moisture barrier to keep freezer burn low. - control emulsions - add stabilizers: agars & gums - Control light/UV exposure - opaque (brown) bottles to minimize skunking. - Control oxygen - modified atmosphere packaging with inert gas

Preventing Deterioration Biological (Bacteria, Viruses, Rodents, Insects)

- Discourage cross-contamination and maintain clean facilities with SSOPs (Sanitation Standard Operating Procedures). Maintain Employee GMPs (Good Manufacturing Practices, such as an employee hygiene plan). - Keep a PMP (Pest Management Plan) up to date and maintain indoor and outdoor spaces accordingly.

7. Physical Factors > Organoleptic Deterioration

- Loss of texture due to freeze-thaw cycling - Emulsion destruction (separation of oil and water phase in a product like mayonnaise). - discoloration (from oxidation of pigments)

Preventing Deterioration Chemical

- Obtain nitrites pre-measured as part of a salt/seasoning mix and obtain a letter of guarantee from supplier and certificate of analysis from a private lab showing that the product is what it claims to be (move liability onto someone else). - Use GMPs when handling cleaning chemicals, lubricants and solvents and inspect equipment and facility regularly.

Preventing Deterioration Biological (Prions)

- Only way to prevent is by Good Agriculture Practices (do not feed meat ingredients to vegetarian animals). - UK, EU, Japan, and US have all passed measures banning use of animal ingredients in ruminant feeds.

Preventing Deterioration Biological (Parasites)

- Parasites can also be killed by freezing - The Fish and Fishery Products Hazards and Controls Guide recommends a temperature below -4F for 7 days or -31F for 15h to kill the fish nematodes.

6. Chemical Factors > Safety Deterioration

- Residues of chemicals above FDA-approved limits - grease and paint chips from food processing machinery - overaddition of process aids and ingredients.

3. Biological Factors > Nutritional Deterioration

- Unwanted bacteria, mold and yeast in a food product can metabolize macronutrients into detrimental end-products - Spoilage bacteria can break down cell membranes and walls, resulting in oxidation of fatty acids (destruction of omega 3s) and destruction of vitamins that are oxygen sensitive.

What is food deterioration

- any adverse change of a food's attribute from an agreed upon measure of quality (subjective).

Preventing Deterioration Biological (Bacteria, yeast, mold cont....)

- control pH - bacteria, mold, and fungi can be inhibited by lowering the pH. Canned foods can be classified as low acid (pH>4.6) or acid (pH<4.6).

8. Physical Factors > Nutritional Deterioration

- light causes increased loss of vitamins A, C, and Riboflavin (B2) by oxidation.

1. Biological Factors > Safety deterioration Biological factor: bacteria

1). Bacterial safety deterioration manifests as illness, which can occur because of: A. Infection: Invasion, growth, and subsequent damage to the host's tissue. B. Intoxication: illness caused by ingestion of a toxin formed by bacteria before the food is eaten.

What are the types of food deterioration?

1). Organoleptic (quality) 2). Nutritional 3). Safety

What factors cause food deterioration

A). Physical Factors B). Biological Factors C). Chemical Factors

2. Biological Factors > Organoleptic Deterioration

A. Endogenous food enzymes -ie: polyphenoloxidase, trimethylamine oxidase (flesh toughens) B. Enzymes from Bacteria, yeast, and mold. - bacteria, yeast and mold release enzymes to digest the food for themselves to release nutrients. Causes food to break down, lose cell wall integrity of f+v- speed spoilage. C. Enhanced food spoilage from rodents/insects - food is exposed to the elements when packaging.storage or food itself is penetrated by vermin, allowing in deleterious physical and chemical elements.

1. Biological Factors > Safety deterioration Biological factor: prions

A. Prions-infectious agents consisting of a sequence of amino acids (protein), whose conformation (structure) has very low potential energy compared to that of similar proteins in the body. Somehow prions induce conformational change in these healthy proteins, resulting in all proteins adapting the prion conformation. Once changed, the proteins cannot achieve the higher energetic state ever again. Prions cannot be destroyed by enzymes, sanitizers, or by cooking temperatures.

1. Biological Factors > Safety deterioration Biological factor: protozoa, parasites

A. Protozoa -Cryptosporidium parvum (cow feces), Cryptosporidium hominis (human feces), and Toxoplasma gondii (cat feces) all have oocysts as part of their life cycle. All cause diarrheal symptoms. B. Parasites - Round Worms/nematodes, Flat worms/trematodes, tapeworm/cestodes.

1. Biological Factors > Safety deterioration Biological factor: molds, viruses

A. Toxic molds - some molds that grow in food products produce toxins that may cause cancer in humans. B. Viruses - 10-100 times smaller than bacteria, contain DNA but require host cell machinery to replicate. Usually originate from fecal contamination, causing diarrheal diseases. The majority of foodborne illness in the US is caused by one virus: Norwalk, causing 58% of US foodborne illnesses reported annually. Another virus sometimes in food is Hepatitis A.

5. Chemical Factors > Nutritional Deterioration

Harsh chemical conditions create unstable conditions for many vitamins, resulting in degradation.

4. Chemical Factors > Organoleptic Deterioration

Many colors (especially natural ones) are unstable and appear as different colors at different pH values . Addition of too much acid or base can ruin an unbuffered product.

1. Biological Factors > Safety deterioration Biological factor: pests

Pest safety deterioration manifests as A. Economic loss - direct food consumption by pests. B. Disease contamination - urine, feces left in food.

9. Physical Factors > Safety Deterioration

Physical conditions like high moisture and heat that favor flourishing of dangerous biological agents (mold, bacteria).