Food Processing and Technology

Written and reviewed by Anjali Sharma, Biology & Home Science faculty at UniDrill (M.Sc. Botany, Banaras Hindu University · 8 years teaching). Based on NCERT Home Science Class XII (Human Ecology and Family Sciences Part I), Chapter 4.

Why does a jar of mango pickle outlast the mango?

A ripe mango on the counter is soft and spoiling within days. The same mango, cut, salted, mixed with oil and spices and packed in a jar, can last a year. Nothing magical happened. The pickle-maker changed the conditions that spoilage organisms need, and that is the whole subject of this chapter. Food processing is a family tradition in India (pickles, murabbas, papads) and a large modern industry, and understanding its principles lets you answer both exam questions and everyday ones, such as why leftover curry should not sit out on a warm kitchen counter.

Why food is processed, and why it matters now

People have dried grain after harvest since ancient times. Early processing aimed at better digestibility, palatability and a continuous supply of food. Improved transport, communication and industrialisation have since made consumer needs more varied. People now ask for fresh, organic, safer and healthier foods that have adequate shelf life, retain nutrients, have particular functional properties and texture, and are easy to package, store and transport. Everyday readymade foods range from biscuits, bread, pickles and papads to ready to eat curries and snacks.

India's position. India has moved from an agro-deficit to an agro-surplus country, which creates a need to store and process farm and garden produce. The Indian food industry ranks fifth in size and contributes nearly 6 per cent of GDP. Changing lifestyles, mobility and globalisation keep raising demand for new products.

FSSAI has laid down fortification standards for staples such as salt, wheat flour, milk and edible oils.

Four terms that sound alike

CUET loves to swap these four. Link each to its key verb.

Milestones in food technology

Pasteurisation is the process of treating milk to destroy disease producing organisms.

Beyond the textbook. For the exam: pasteurisation destroys disease producing organisms in milk, a major advance in food safety. In reality: pasteurisation is a controlled heat treatment that removes disease causing microbes without making the food sterile, which is why pasteurised milk still has to be kept cold and used within its date. Why it matters: "pasteurised" does not mean "will never spoil". Do not mix it up with canning, which was developed earlier by a different person.

Why food spoils

Foods undergo physical, chemical and biological deterioration, shown by spoilage, off flavours, poor texture, discolouration and nutrient loss. That makes food unfit or unsafe to eat. The chapter names the causes.

Microbial growth depends on nutrient availability, moisture, pH, oxygen level and the presence of inhibiting substances. Enzyme activity depends on pH and temperature.

Classes of food by perishability.

Five principles that prevent spoilage

Every method of preservation attacks one or more of the conditions that organisms and enzymes need.

The danger zone. Bacteria prefer protein rich foods such as meat, fish, poultry, eggs and dairy, which are called high risk foods. Bacteria grow at any temperature between 5 and 60 °C, a range called the danger zone.

Pause and predict: a pot of egg curry is left on a kitchen counter at about 30 °C for a whole afternoon. Is it in the danger zone, and is it a high risk food?

Check your answer: yes to both. 30 °C lies between 5 and 60 °C, and egg is a protein rich high risk food, so bacteria can multiply quickly. Keeping cooked food cold, below 5 °C, or hot, above 60 °C, keeps it out of the zone.

Beyond the textbook. For the exam: the danger zone is 5 to 60 °C. In reality: food safety guidance such as the WHO's advises that cooked food should not stay at room temperature for more than about two hours, and should be kept hot above 60 °C or refrigerated. Why it matters: the range tells you the temperature, and the two hour guidance tells you how long, which is what households use in practice.

Classes of processed food

Foods can be classified by the extent and type of processing. CUET asks example-to-class matching.

Two views. For the exam: processing adds value by improving storability, portability, palatability and convenience, and reduces the cook's preparation time. Another reading: nutrition scientists point out that foods high in energy, fat, sugar and salt and low in fibre, when eaten often, can push out whole grains, pulses, vegetables and fruits, which is why processing for health (lower Calorie, fortified, functional foods) has become a goal of the industry. Both views are part of the same story: what matters is which processed foods, and how much.

What a food technologist must know

Food production is seen in three stages. The skills needed grow at each.

Worked example: costing a home made pickle

The chapter's practical asks students to make a preserved product, cost it and label it. Costing includes food materials, energy, labour, and storage and packing material. Suppose a group makes 500 g of mango pickle.

$$\text{Cost per 100 g} = \dfrac{140}{500} \times 100 = 28$$

If the group wants a 25 per cent margin over cost:

$$\text{Selling price for 500 g} = 140 \times \left(1 + \dfrac{25}{100}\right) = 175$$

$$\text{Selling price per 100 g} = \dfrac{175}{500} \times 100 = 35$$

So the cost per 100 g is Rs 28 and the selling price is Rs 35 per 100 g, a profit of Rs 7 per 100 g. A common wrong step is to count only the raw materials (Rs 90) and forget energy, labour and packing, which gives a price that looks profitable but loses money.

Label checklist. A label should carry the name of the product, the name and address of the manufacturer, the ingredients in descending order of proportion, the net weight or volume, instructions for use if any, storage instructions, and the "Use By" or "Best Before" date. For example, a jar might list: mango, oil, salt, chilli powder, fenugreek, in that order if mango is the largest part by weight.

Careers and scope

The food industry covers processing and manufacture, research and development (changing existing products, developing new ones, studying markets, creating new technology), food safety and quality monitoring, quality control procedures, costing, and regulatory affairs. People may specialise in beverages, dairy, meat and poultry, seafood, fats and oils, stabilisers, preservatives and colours, food grains or additives. Professionals need knowledge of food science, food chemistry, microbiology, processing, safety and quality assurance, good manufacturing practices and nutrition, analysis of raw and cooked foods, product specification, sensory evaluation, industry practices, packaging and labelling, information technology, and cooking and recipe skills.

Food technologists work in food industries, quality control departments, hotels, hospitals, labelling and packaging industries, breweries and distilleries, soft drink, dairy, confectionery, fish and meat, fruit and vegetable, and grain, millet, rice and flour mills.

Career avenues listed in the chapter are production manager, project implementation, marketing and sales, sensory evaluation, quality assurance, research and development (product development), project financing, project appraisal, teaching and research, entrepreneurship development, consultancy and technical marketing of products.

Self employment. Food processing has long been a household or cottage activity: sweets, papads, murabbas, pickles, fried snacks, roasted and puffed cereals. Government gives incentives such as finance, training, infrastructure and marketing support, banks encourage women entrepreneurs, and states provide space. A venture can be high technology and investment heavy, or a low key unit such as salted peanuts, drinking water pouches, dehydrated products or pickles.

Industry snapshot (as given in the chapter).

Exam traps

60-second revision

Where this chapter connects

• Previous: Public Nutrition and Health shows why fortified and processed foods are tools against hidden hunger.
• Next: Food Quality and Food Safety covers the safety culture, standards and quality control that processed foods depend on.
• Same unit: Clinical Nutrition and Dietetics uses medical foods and tube feeds, which this chapter lists among processed foods.
• Related: Consumer Education and Protection explains why labels such as the "Best Before" date protect the buyer.