UNIT V: Advanced Processing, Waste Management & Food Safety
1. Dried and Dehydrated Products
Drying: Usually refers to drying under natural sunshine (uncontrolled conditions).
Dehydration: Drying under controlled conditions of temperature, humidity, and airflow (artificial).
Principles of Drying
- Moisture Reduction: Reducing moisture content from >80% to <5% (for fruits) or <15-20% (for dried soft fruits like dates/figs).
- Water Activity (aw): Reducing aw below 0.6. (Bacteria need >0.9; Molds need >0.7).
Methods of Drying
- Sun Drying: Spreading fruit on trays/roofs.
Pros: Cheapest method.
Cons: Slow, hygienic risk (dust/insects), weather-dependent, poor color (browning).
Examples: Raisins (Kishmish), Figs, Dates. - Solar Drying: Using solar dryers (glass/poly-sheet covered boxes) that trap heat (Greenhouse effect). Faster and more hygienic than open sun drying.
- Mechanical/Tray Drying (Cabinet Dryer): Fruit is placed on trays in a heated cabinet. Hot air (usually 60–70°C) is blown over the fruit. Most common industrial method.
- Spray Drying: Liquid juice is sprayed as a fine mist into a hot air chamber. The mist dries instantly into powder.
Example: Fruit juice powders, Mango powder. - Freeze Drying (Lyophilization):
Mechanism: Sublimation. Fruit is frozen, then placed in a vacuum. Ice turns directly into vapor without melting into water.
Quality: Best retention of shape, flavor, and nutrients. Rehydrates perfectly.
Cost: Very expensive. Used for high-value exports (e.g., Strawberry slices for cereal).
Flow Chart for Dehydration:
Selection → Washing → Peeling/Slicing → Sulphuring (SO2 fumes to prevent browning) → Drying → Sweating (Equalizing moisture in bins) → Packaging.
2. Nutritionally Enriched Products
Types of Enrichment
- Fortified Juices/Beverages:
Adding Vitamin C (Ascorbic acid) to apple/grape juice (which naturally lack it).
Adding Calcium to orange juice.
Adding Protein (Whey isolate) to fruit smoothies. - Functional Foods: Products containing "Bioactive compounds" that promote health beyond basic nutrition.
Example: Probiotic Fruit Drinks (Juice + Lactobacillus bacteria). - Fruit Bars/Leathers: Mango leather (Aam Papad) fortified with soy protein or iron.
- Blended Beverages: Mixing nutritious but poor-tasting juices (Aonla/Aloe Vera) with tasty juices (Guava/Pineapple) to improve palatability and nutrition.
Example: Aonla + Ginger + Honey.
3. Fermented Fruit Beverages
Major Fermented Products
- A. Wine: Fermented juice of Grapes (usually Vitis vinifera).
Alcohol Content: 7% to 15%.
Yeast Used: Saccharomyces cerevisiae var. ellipsoideus.
Types:
Red Wine: Fermented with skin (skin gives color and tannins).
White Wine: Fermented without skin (juice only).
Sparkling Wine (Champagne): Contains trapped CO2 (fizzy). - B. Cider: Fermented juice of Apples. Alcohol Content: 4% to 8%. Common in Himachal Pradesh and J&K.
- C. Perry: Fermented juice of Pears.
- D. Vinegar: Produced by a double fermentation:
Alcoholic Fermentation: Yeast turns Sugar → Alcohol.
Acetic Fermentation: Bacteria (Acetobacter) turns Alcohol → Acetic Acid (Vinegar).
Standard Vinegar contains 4% Acetic Acid. - E. Fenny: Distilled liquor made from Cashew Apple or Coconut. (Goa GI Tag).
4. Packaging Technology (Advanced)
A. Aseptic Packaging (Tetra Pak)
Process: The product (Juice) and the package (Carton) are sterilized separately. The filling is done in a sterile environment.
Material: A 6-layer laminate (Paper + Polyethylene + Aluminum foil).
Benefit: Long shelf life (6 months) at Room Temperature without preservatives.
B. Retort Pouching
Flexible pouches made of Aluminum + Plastic laminate.
Food is sealed inside and then heated (retorted/autoclaved).
Advantage: Replaces metal cans ("Flexible Cans"). Lighter weight, easy to open. used for Ready-to-Eat curries or fruit pulps.
C. Vacuum Packaging
Air is sucked out before sealing.
Prevents oxidation and aerobic microbial growth.
Used for dried fruits and nuts.
D. Active Packaging
The package interacts with the food.
Oxygen Scavengers: Sachets inside the pack absorb O2 to prevent rancidity.
Ethylene Scrubbers: Sachets absorb ethylene to delay ripening.
5. Processing Waste Management
Fruit processing industries generate 30–50% waste (peels, stones, cores), which creates pollution. This waste can be converted into "Wealth".
Utilization of Waste by Crop
- 1. Mango:
Peel: Extraction of Pectin (jelly making) and dietary fiber.
Kernel (Seed): Contains 8–10% fat (Mango Kernel Oil) used in confectionery as a cocoa butter substitute. Also rich in starch. - 2. Citrus (Orange/Lime):
Peel:
Essential Oil: Extracted by cold pressing (flavoring agent).
Pectin: Citrus peel is the richest source of pectin.
Candied Peel: Preserved in sugar. - 3. Apple:
Pomace (Solid residue after juicing): Dried and used for Pectin extraction or Animal Feed. - 4. Banana:
Pseudostem: Fibre extraction for paper/textiles.
Peel: Biogas production or composting. - 5. General Waste:
Biogas: Anaerobic digestion of organic waste produces Methane (fuel).
Composting: Vermicomposting to produce manure.
6. Food Safety Standards
Ensuring food is safe for human consumption is a legal requirement.
A. FSSAI (Food Safety and Standards Authority of India)
- Established under the Food Safety and Standards Act, 2006.
- It replaced all older orders (like FPO, PFA).
- Role: Sets science-based standards for food items, regulates manufacturing, storage, and distribution to ensure safety.
- Mandatory: Every food business operator (FBO) must have an FSSAI license/registration.
B. Codex Alimentarius
- "Food Code" established by FAO and WHO (United Nations).
- Sets International standards for food safety and fair trade.
- Important for Exports. If you want to export mango pulp, you follow Codex standards.
C. HACCP (Hazard Analysis and Critical Control Point)
Crucial for Exams. A preventive system to ensure food safety.
It does not test the final product; it monitors the process to prevent errors.
The 7 Principles of HACCP:
- Conduct a Hazard Analysis: Identify where things can go wrong (e.g., bacteria at filling stage).
- Determine CCPs (Critical Control Points): Steps where control can be applied to eliminate the hazard (e.g., Pasteurization temperature).
- Establish Critical Limits: (e.g., Temp must be ≥ 95°C).
- Establish Monitoring Procedures: (e.g., Check temp every 10 mins).
- Establish Corrective Actions: (e.g., If temp drops, re-pasteurize).
- Establish Verification Procedures: (e.g., Lab test the final juice).
- Record Keeping: Maintain documentation of all checks.
D. ISO 22000
An international standard that combines HACCP with quality management and general management principles for food safety, all within a risk-based, process-oriented approach.
It is the international standard for Food Safety Management Systems (FSMS), providing a framework for organizations in the entire food chain (farm-to-fork) to control hazards, ensure safe food, and improve performance.
It helps businesses demonstrate consistent ability to provide safe food, applicable to any size organization from producers to retailers, and is certified to build stakeholder confidence
📚 References
Srivastava, R.P. & Kumar, S. (2002). Fruit and Vegetable Preservation: Principles and Practices. International Book Distributing Co.
Lal, G., Siddappa, G.S. & Tandon, G.L. (1986). Preservation of Fruits and Vegetables. ICAR.
Potter, N.N. & Hotchkiss, J.H. (1995). Food Science. CBS Publishers.
FSSAI Website & Manuals (for regulatory updates).