(a)(i) Discuss the modern processing technologies to improve quality of meat and meat products. (10 marks) (a)(ii) Packaging is…

(a)(i) Modern Processing Technologies to Improve Meat Quality

Modern technologies aim to improve safety, tenderness, colour, flavour and shelf life while reducing chemical additives.

1. Improving tenderness and eating quality: electrical stimulation of carcasses soon after slaughter speeds up rigor and prevents cold shortening; controlled chilling and ageing (dry or vacuum ageing) allow natural proteolysis; mechanical tenderisation (blade or needle), injection and tumbling with brine or marinades improve juiciness; and enzymes such as papain or bromelain are used for tough cuts.
2. Non-thermal preservation: high-pressure processing (HPP, 400–600 MPa) inactivates vegetative pathogens (Listeria, Salmonella, E. coli) in ready-to-eat products without cooking; irradiation (gamma rays, electron beam or X-rays at low kGy doses, permitted for meat and poultry under the Atomic Energy (Radiation Processing of Food and Allied Products) Rules, 2012) reduces pathogens and parasites and extends shelf life; pulsed electric field (PEF) treatment tenderises meat and speeds curing and marination; and cold plasma, ultraviolet light and organic-acid sprays are used for surface decontamination.
3. Thermal technologies: sous-vide cooking in vacuum packs at controlled low temperature, ohmic and microwave heating, and retort processing of shelf-stable products.
4. Restructuring and value addition: binding meat pieces with transglutaminase or salt-soluble proteins to make uniform products; emulsion technology for sausages, nuggets and patties; and incorporation of fibre, plant extracts (antioxidants) or reduced salt and fat for healthier products.
5. Hurdle technology: combining mild barriers (low water activity, pH, mild heat, preservatives, packaging) to produce shelf-stable traditional products such as meat pickles and dried meat.
6. Quality assurance: HACCP, rapid detection methods (PCR, biosensors), and traceability systems.

(a)(ii) Packaging for Marketing of Meat and Meat Products

Packaging protects meat from microbial contamination, moisture loss, oxidation and physical damage, and at the same time carries the brand, labelling and information that sell the product.

Traditional packaging: meat in India is still mostly sold fresh in wet markets, wrapped in leaves (banana, sal), newspaper, cloth or polythene bags, or carried in earthen or metal containers; traditional products such as meat pickles are stored in glass or ceramic jars. These methods are cheap and locally available, but give little protection against contamination and spoilage, allow no labelling or branding, and do not meet modern food safety expectations.

Modern packaging:

1. Overwrap trays: foam or plastic trays wrapped in oxygen-permeable film for retail display of fresh meat, keeping the bright red oxymyoglobin colour for a few days.
2. Vacuum packaging: removes air before sealing in low-permeability film; greatly extends refrigerated life of primal cuts and processed meats; skin (vacuum skin) packaging improves appearance.
3. Modified atmosphere packaging (MAP): high-oxygen mixtures (about 70–80% O₂ with 20–30% CO₂) keep red meat bright red, while low-oxygen mixtures (CO₂ with N₂) are used for poultry and cured products; CO₂ inhibits spoilage bacteria.
4. Active packaging: oxygen scavengers, carbon dioxide emitters, moisture absorbers and antimicrobial films.
5. Intelligent (smart) packaging: time–temperature indicators, freshness indicators and RFID tags for traceability.
6. Retort pouches and cans for shelf-stable ready-to-eat meat products, and edible or biodegradable films for sustainability.

Role in marketing: attractive, hygienic retail packs build consumer confidence and brand identity; portion packs and ready-to-cook products offer convenience; longer shelf life allows wider distribution through supermarkets, e-commerce and exports; and labels provide the information required under the FSS (Labelling and Display) Regulations, 2020 (name, ingredients, nutrition, dates, the non-vegetarian symbol and FSSAI licence number). Packaging thus lets organised processors command premium prices compared with loose meat.

(b)(i) Abattoir Effluent Treatment

Abattoir effluent contains blood, fat, dung, paunch contents, hair and cleaning water, and has very high BOD, COD, suspended solids, oil and grease, nitrogen and pathogenic organisms. Blood alone has a very high BOD, so blood recovery at source is the first step. Treatment is needed to meet the discharge standards for slaughterhouses notified by CPCB under the Environment (Protection) Rules, 1986, and the consent conditions of the State Pollution Control Board.

1. In-plant measures: collection of blood for processing, dry removal of dung and paunch contents, separate drainage of clean water, and water-saving equipment.
2. Preliminary and primary treatment: screens to remove solids, fat traps, equalisation tank, and sedimentation or dissolved air flotation (DAF) to remove fat and suspended solids.
3. Secondary treatment: anaerobic treatment (anaerobic lagoons or upflow anaerobic sludge blanket reactors), which removes much of the BOD and produces biogas, followed by aerobic treatment (activated sludge, extended aeration or aerated lagoons).
4. Tertiary treatment: filtration, disinfection by chlorination or UV, and nutrient removal before discharge or reuse for irrigation.
5. Sludge handling: sludge from primary and secondary treatment is digested or composted and used as manure.

(b)(ii) Processing of Condemned Carcasses into Meat-cum-Bone Meal

Condemned carcasses, organs and trimmings unfit for human food are processed by rendering, which sterilises the material, separates fat (tallow) and produces a dry protein meal. Carcasses of animals that died of anthrax or other notifiable diseases must not be rendered; they are incinerated or deep-buried.

Methods:

1. Wet rendering: raw material is cooked with live steam under pressure in a digester (autoclave); fat floats and is drawn off, and the residue (tankage) is pressed and dried. It gives good-quality fat but a lower-quality meal with loss of solubles.
2. Dry rendering (batch): material is chopped and cooked in its own fat in a horizontal steam-jacketed cooker with an agitator, first under pressure to sterilise and then under vacuum or at atmospheric pressure to drive off moisture; the cooked mass is drained and pressed (expeller) to separate tallow.
3. Continuous dry rendering: raw material is fed continuously through a cooker and presses, giving higher throughput, better hygiene and lower energy use.

Steps common to all methods: collection and crushing to a small particle size; cooking and sterilisation (a widely used standard is at least 133°C at 3 bar pressure for 20 minutes with particle size not more than 50 mm); separation of fat; drying of the greaves to less than about 10% moisture; grinding, sieving and removal of metal; and packing. The meal typically contains about 45–55% protein, with calcium and phosphorus from bone.

Rendering reduces but does not reliably destroy prions, so many countries prohibit feeding ruminant-derived meat-and-bone meal to ruminants. The meal is used in poultry, pig and pet foods where permitted, and as an organic fertiliser; tallow is used for soap and industrial purposes.

(c) Industrial Casein: Classification and Manufacture of Acid Casein

Classification of industrial casein from skim milk:

1. Acid casein, precipitated by lowering pH to the isoelectric point (about 4.6): mineral acid casein (hydrochloric or sulphuric acid) and lactic acid casein (natural souring or lactic starter).
2. Rennet casein, precipitated by the enzyme rennet (chymosin) as calcium paracaseinate; high in ash; used for casein plastics (galalith) and cheese analogues.
3. Co-precipitates, in which casein and heat-denatured whey proteins are precipitated together by heat and calcium chloride or acid.
4. Caseinates, derived products made by neutralising acid casein with alkali: sodium, potassium, calcium and ammonium caseinates, which are water-soluble and used in foods.

Industrial (technical) acid casein is used for adhesives and glues, paper coating, paints, leather finishing and textile fibres, while edible grades are used for caseinates and food products.

Manufacture of acid casein:

1. Skim milk with less than about 0.1% fat is used, because fat lowers quality.
2. Precipitation: the milk is warmed to about 30–35°C and dilute acid (hydrochloric or sulphuric acid, or lactic starter) is added with stirring to bring the pH to 4.5–4.7.
3. Cooking: the curd–whey mixture is heated to about 45–50°C to firm and aggregate the curd.
4. Separation: the whey is drained off using screens, decanters or centrifuges.
5. Washing: the curd is washed two or three times with clean water to remove acid, lactose and salts, which improves colour and keeping quality.
6. Pressing or dewatering: to about 50–55% moisture.
7. Drying: in tunnel, fluid-bed or attrition driers at controlled temperature to about 8–10% moisture.
8. Grinding, sieving, tempering and packing in moisture-proof bags.

Quality: protein at least about 90% on a dry basis, moisture not more than about 10–12%, fat not more than about 1.5%, low ash and free acid, good colour, and freedom from burnt particles and contamination.