Pondering Over Pasteurization

Pasteurization is a mild heat treatment used to  destroy  the pathogenic bacteria that spoil food.  Even though so many technologies of preservation are used, pasteurization remains paramount.

Three different methods of pasteurization

Vat pasteurization where milk is heated at 63-degree Celcius for thirty minutes, and then cooled, this is mostly used for cheese and yogurt processing.

HTST process where milk is heated at 72-degree Celcius for 15 seconds and then cooled. It is the most widely used method of heat treatment.

UHT process where milk is heated at 140-degree Celcius for 4 seconds and then cooled this method has the highest shelf life.

There can small changes in temperature according to the product or process.

The continuous pasteurization is carried out by passing food through plate heat exchangers in four stages.





Components of HTST pasteurizer

Process of pasteurization

 In a plate heat exchanger counter-current flow is used,  Gaskets are provided to prevent leakage. It consists of a series of metal plates that are closely packed and are corrugated to increase the turbulence of liquids. The function of the plate heat exchanger is to heat raw milk to a certain temperature (60-deg) with the help of pasteurized milk. 

And then this is sent to the heater where it is heated to pasteurization temperature and is held in the holding tank for a predetermined time, so that pasteurization is complete, and passed to the cooler. And then pasteurized milk is sent to the chiller where the temperature is further reduced to about 5-deg Celsius.


To kill pathogens in food that are responsible for spoilage and increase shelf life of the product.

 Around the world with food technology

Louis Pasteur along with his great contributions, to science, has found the pasteurization process without which beverage preservation in industries around the world, would be incomplete even today. This was the basic for different advanced preservation techniques of today.

Antioxidants for health

Peanuts are rich in antioxidants and flavonoids, that perform the removal of free radicals, thereby preventing diseases. Snack on peanuts as they have a nutrition profile as healthy as almonds. You can have a hand full of them every day.

Pasteurization for life

To get rid of any hindrance in your path to success, you need to destroy a few self-created obstacles procrastination, self-doubt, a pessimistic attitude that can bring down enthusiasm, and delay success.

An interesting piece of information

pasteurization was found to extend the shelf life of red wine, but later it was also widely used for milk.

Ode Not Poetic To Ohmic Heating

Ohmic heating is a process of heating food though passing an alternating electric current that results in rapid yet uniform heating of the product.

Conventional heating leads to loss of nutrients or overheating, but in ohmic heating, due to internal heat generation, efficient heating with no energy loss happens.

The main aim is to kill pathogens in food, and also preserve the nutritional and sensory properties of food to the maximum level possible.

The food acts as an electrical resistor and is heated by the dissipation of electrical energy. In short,

V = IR works here.        

An ohmic heating system consists of

The  main factors that influence the ohmic heating process are electrical field strength, residence time and electrical conductivity of food, viscosity, temperature, voltage gradient which influence temperature generation and ohmic heating efficiency.


It is used for processing heat-sensitive liquid foods that contain large particulates like fruit juices, soups, syrups, sauces, protein-rich foods like eggs that denature when thermally processed.

Around the world with food technology

Different companies that make pulpy orange juice, Puddings with fruit slices, soups, and processed egg have ohmic heating as a part of their processing.

Antioxidants for health             

Onions contain a high amount of vitamin c and quercetin a flavonoid that contributes to the antioxidant activity that prevents oxidative stress and cell damage. Include onions as you always do and make sure you stay healthy and safe.

Four red onions isolated on white backgroun

Ohmic heating for life

Have an optimistic approach in life that even stress would have very little effect on your mental and physical well being like the effect Ohmic heating has on food.

An interesting piece of information

The ohmic heating system was first introduced by APV baker limited New Delhi, India for heating particulate food products.

Nano world

Nanotechnology deals with materials with a particle size of 1-100 nm that have unique properties, unlike their macro scale counterparts, and these peculiar characteristics are used to develop new and improved products.


Nanotechnology has two wide applications in food processing

Food nanostructured ingredients and food nano sensing.

Nanoparticles are used in food additives, carriers for smart delivery of nutrients, anticaking agents, antimicrobial agents, fillers for improving mechanical strength to food packaging material.

Food Nano sensing is applied to achieve better food quality and safety evaluation.

The nanostructured food ingredients offer improved taste, texture, and consistency, shelf life, and also help to reduce wastage of food. Nano carriers are utilized as the delivery system to carry food additives in food products as these are better absorbed effectively, than the large size micro particles. It is used in the development of improved colloids, biopolymer matrices, emulsions and formation of encapsulation.

The properties of an ideal delivery system able to deliver the active compound, precisely at the target place,

ensure availability at the target time, and specific rate,

efficient to keep active compounds at suitable levels for a long time.

Nano sensors are used for pathogen detection in food industries. with high sensitivity, they ensure better levels of food safety.  

Around the world with food technology                           

    Food packaging finds a new way with silver nanoparticles being used for providing a barrier against microbial spoilage in carbonated beverages.

Antioxidants for health

Nutmeg is rich in antioxidants including plant pigments, phenolic compounds that help fight free radicals and thus prevent us from diseases.

Nanotechnology for life

If you want to master an art you got to observe every minute detail of it because every tiny piece of information will have its importance.

 Little drops of water make a mighty ocean. 

With  a tiny yet consistent effort, you can even learn something you have never tried before say you can learn a new language or Calligraphy during these lockdown days or anything that interests you may be  singing, dancing, sketching. 

An interesting piece of information

 Nano wine is engineered and it has nano capsules of different flavors in the same wine so you can taste many flavors in one drink.

MAP Of Food Technology

MAP is modifying the atmosphere inside the food package, so the shelf life of food is extended along with providing a barrier that prevents deterioration.

These are three main gases, involved in creating the special modified atmosphere. A gas balloon reaches a great height when left to fly isn’t it? Same way MAP extends the freshness of food for long time as compared to air packaged food.

  1. Oxygen                       

2. Carbon dioxide

3. Nitrogen 

The change in concentration of the gases results in the ideal atmosphere.

 A minimum level of oxygen is maintained in food packaging as it results in oxidation of food into constitutive parts and oxygen also leads to the rancidity of fats and oils.

Nitrogen is inert but acts as a cushion and prevents the package from collapsing.

Carbon dioxide is responsible for preventing spoilage due to bacteria and fungi. It also retards the growth of moulds and aerobic bacteria.

This modified atmosphere is created either by passive modification or active packaging.

Passive modification where the respiring product, is placed in a polymeric package and hermetically sealed.

The product’s respiration characteristics,  packaging material permeability must be in such a way that a beneficial modified atmosphere is established successfully.

Active modification is of two types

Gas flushing

 The air is replaced by passing a stream of gas. The air gets diluted and the pack is sealed, the oxygen level in the package is about 2-5%.

Compensated vacuum

Here, a vacuum is first applied to remove the air, and then the desired gas or gas mixture is introduced in the food package.

Active packaging

 Certain additives are incorporated into the package to modify the headspace atmosphere.  For e.g oxygen scavengers or carbon dioxide absorbents are used along with the moisture barrier offered by the package.

Storage temperature is very important in extending the shelflife of MAP products. Ideally, 0-5 degrees Celsius is used as storage temperature for most products.


 Extended shelf life.

Improved preservation.

Increased flexibility of packaging and distribution.

Around the world with food technology                   

Companies around the world today, use MAP for perishable food products like fruits, vegetables, and raw meat but McDonald’s introduced the application of MAP technology for bulk packaging of lettuce to be distributed to their retail stores.

Antioxidants for health

No doubt, this fruit is the first love of every fruit lover. It has the power to indulge all our senses and takes our taste buds to an exotic journey with every bite. This super food is none other than mango, it almost contains a dozen antioxidant compounds, including catechins, mangiferin, anthocyanin that are the need of the hour.

MAP for life

Even for us, it is very vital to modify our inner atmosphere so that we give time for self-exploration, and do what gives us peace of mind, along with boosting our creativity, that imbibes every cell in our body with happiness.

If you cannot go out, go in and make sure you stay strong, stay home and stay safe.

An interesting piece of information

Freshness can be doubled or even tripled with MAP. Hard cheese has a shelf life of about three weeks when air packed, but it lasts fresh for about 10 weeks with MAP.

Lift Your Buying Spirit By Reading Labels

Food labeling is the simplest way through which food manufacturer communicates useful information to the buyer so that they can make their buying decision in a much easier and smart way. 

A dozen of the mandatory information

  1. The name – Name of the food product is the first and foremost because it says it all.
  2. Ingredients list must include the word ‘ingredients’ along with different ingredients used for producing the product listed in descending order of weight. 
  3. Quantitative Ingredient declaration or QUID 

There must be a quantitative representation denoted in percentage that is placed next to the different ingredients in the list giving information about how much percentage of different ingredients are used.  

 4. Net quantity is the weight or volume of the product without the packaging given in metric units.

5. Instruction for use

General instruction on how to use/prepare the food before consumption given by the manufacturer.

6. Product durability indication

This is of two types 

  1. Best before: This is used for pre-packaged food. The food is of the best quality when used before this date.
  2. Use by: This is used on perishable foods where spoilage is easy when used after the use-by date.

7. Storage condition

For dry product                 

Store in a cool, dry place

For a fridge product

keep refrigerated

For frozen product

Store frozen below-18 degree Celsius

Do not refreeze once thawed.

8. The business name and address of the business operator is provided.

9. Country of origin

 It becomes mandatory when the food is produced in a country and sold in some other country.

10. Food allergens

Mentioning food allergens are helpful to customers when making the right choice of food in case of intolerance to a certain type of food.

11. If a health claim is made about the product, say high fiber or cholesterol-free, nutrition information should be provided.

12. Alcohol strength must be provided if a drink contains alcohol.


  1. It gives knowledge to the consumer about the food they buy.

2. It helps buyers to make better-informed choices.

3. It helps consumers to use and store food safely.

Around the World with food technology

Nutrition labeling is of great interest all over the world because it provides an opportunity to highlight and revitalize healthy eating and thereby completes the full circle of healthy eating by helping customers make better and smarter food choices.

Antioxidants for health

Lemon is a great source of vitamin C and flavonoids that are known to remove free radicals from our body that help prevent diseases and promote well being. It is great to use frozen lemon with peel, you can grate it over your hot soup and get to enjoy the trio of health, taste, and flavor.

Labelling for life 

It is great to be aware of one’s own strengths and weaknesses, but we should not judge or label any person for who they are, because we never know what they lived through and it is a fact that everyone gets better with time. 

An interesting piece of information

Sulfites are considered incidental ingredients and may not be listed on the ingredient list on a food label. Even though there are about 14 allergens, only eight of them are subject to food allergen labeling and consumer protection act. (FALCPA)

Kindling The Power Of Food Enzymes

Health is one of the greatest gifts from God, and it takes a lot of effort to maintain good health. It is very necessary because the body is the temple where your soul resides. Health and happiness are interrelated. 

 Food enzymes are catalysts that speed up the biochemical reactions in our bodies. If biochemical reactions in the body take place properly, good health is a guaranteed outcome.

A small list of enzymes present in fruits 

  1. Pineapple contains a protein-digesting enzyme called bromelain, it has a powerful ability to break down proteins.
  2. Papaya contains an enzyme called Papain, which aids in the digestion of protein, it is used in food industries, for the tenderization of meat.
  3.  Apricots contain a treasure-trove of enzymes, one of the chief enzymes called invertase, facilitates quick energy absorption by breaking down sucrose into glucose and fructose. 
  4. Kiwi contains an enzyme called actinidin that breaks down protein, gluten, and gelatin. 
  5. Avocado contains an enzyme called lipase, that breaks down dietary fat. Guava also contains a lot of healthy enzymes. If not avocado or kiwi, you can go for Guava as it contains oxidizing enzymes, namely, Ascorbic acid oxidase, Polyphenol oxidase, and Peroxidase.

How do enzymes work?

Lock and key model explains, that the enzyme has a specific place(active site) where the substrate fixes itself to form the temporary enzyme-substrate complex that further gives the final product. 

Induced fit theory where during the formation of the enzyme-substrate complex, the enzyme undergoes a change in shape to fit the substrate and regains its original shape when the product is formed.

Substate strain theory 

Here the substrate is strained due to the change in the shape of the enzyme, and this strained substrate leads to the formation of the product. 

A synergy of induced fit theory and substrate strain theory explains enzyme action.

Application: Every food industry from bread to wine uses a specific enzyme for processing.

Around the world with food technology 

The keto trend 

Ketosis is a natural process that happens when you stop eating carbs. As a result, the ketone level increase in your body. In this, your body uses fat and proteins as fuel instead of carbohydrates. This is one good way to reduce your extra weight to eat fewer carbs and substitute with fat and protein. But it is not good when excess ketones accumulate in the blood. Be sure to get help from your Dietician before planning your keto diet. 

Antioxidants for life 

 A combination of fruits will work as a superfood, plus it serves as a great source of free radical scavengers, that help you stay fit. 

Stay fit, stay home, and stay blessed.

Enzymes for life 

Motivation, encouragement, and kindness in words can work miracles as they speed up the soul, pouring a lot of happiness into it. If you can’t give anything, give hope!

An interesting piece of information 

Bee pollen is a superfood, as it contains 5000 unique enzymes it helps in strengthening our immune system 

Joyful Journey To Space

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“Space foods”     

I want to take all my readers on a space journey to explore space foods and the technologies involved. I hope all my readers would enjoy this journey so let us give it a start…

Have you ever wondered what Astronauts in space eat? Come let’s explore together.

There are special rules for space foods

1. Minimize the crumbs.

2. Minimize packaging and thrash volume.

3. Minimize the weight of the food.

Applications at space

Rehydratable foods : Most foods in space was packaged in a dehydrated form and thus rehydrated before consumption(hot  cup noodles is one fine example ) these foods are packed in special containers to help them last longer dehydration or removal of water is done to prevent spoilage due to microorganisms and extend shelf life.

  The straws used for consumption of liquid food in space has a special one-way valve to prevent the liquid from escaping when not in use. (eg) soups, ravioli and even fruits and fish and eggs, chicken, cheese cereals, etc are packaged dehydrated form and rehydrated before consumption.

Freeze-dried foods

freeze-drying is a process of dehydrating frozen food under vacuum condition so that the moisture content in food directly changes to gaseous form without having to undergo the intermediate liquid state through sublimation the  food product thus maintains good quality and acceptance.

Thermostabilized foods

The foods that are heated to high  temperatures to prevent bacterial growth and are packaged in bimetallic or aluminium cans or flexible retort pouches for instance mushrooms, tomatoes, eggplant are few examples of thermostabilized foods.

Intermediate moisture foods

These are technologies that does not remove water completely but here the water is restricted to an amount to keep the food at desired texture but the percentage of water in IMF foods does not support microbial growth  and the water content in IMF foods ranges from  15 to 30 % thus the water present is chemically bound to salt or sugar and thus not available for microbial growth and prevents spoilage due to micro-organisms dried peaches, pears and apricots are some examples of IMF foods in space.

Vacuum packaging

Some foods are consumed in natural form but there is an interesting technology that is involved here too. Here the air is completely removed from the packaged food.  The package is sealed so that food stays fresh for a long time.

Condiments  are made available suspended in oil or dissolved in water pepper is suspended in oil while salt is dissolved in water these liquid salt and liquid pepper are stored polyethylene bottles.

Modified atmospheric packaging

Bread sandwiches are not possible in space  as the bread slices tend to float so food scientists at NASA developed tortillas – a flatbread made of wheat flour to serve the purpose they kept it fresh up to  one year by the use of oxygen scavengers which helps in removing the oxygen in the package and thus creating a modified atmosphere. Ethylene is an example of oxygen scavenger.

Food irradiation

Some foods are exposed to radiation to kill mould or bacteria on food also to extend its shelf life. Exposure of ionizing radiation in the form of x rays, gamma rays and electron beam to destroy microorganisms. Safety limits of radiation are set according to the type of food and the purpose of irradiation.

Around the world with food technology

NASA’s  first scientist to eat food in space was John Glenn. First food to be eaten in space was Apple sauce. In the second space program NASA food scientists included Shrimp, Cocktail, Chicken, Vegetables and Pudding .

Antioxidants for health

Jackfruit is rich in vitamin-C that is essential for preventing us from diseases and also help boost up our body’s metabolism.

Indian space foods

Food scientists at  DRDO and CFTRI Mysore are exploring new technologies to make available the specialties of  Indian cuisine. DRDO has created initial success in biscuits, pastries and  dried juice and lemon rice with a list of  innovative technologies which are to be later discussed in the blog. Food scientists has formulated even chicken biryani which is supplied to astronauts and it has a shelf life of up to one year.

Space food technology for life

Dream is like the air you breathe. Even a dream to live at zero gravity and eat earth’s delicious food comes true with courage and faith and these incredible food technologies. So have a dream that travels beyond the horizon because if your intentions are right, the universe will help to transform it into a reality .

Some interesting information

  1. TANG one  of the well-known juice brands became famous when it was supplied to astronauts  in the space shuttle it served as a vitamin C  supplement.
  2. As the space shuttle is shielded from Cosmic rays the scientist does not get enough of the sunshine vitamin so special care should be taken to provide vitamin D in the diet of space scientist.

Introducing Irradiation

 Food is always related to energy. But for a change today, we will relate it to ionising radiations.   

‘The energy emitted by radioisotopes keeps our body’s energy level high.’ I am sure the sentence must have surprised most of you. But it is a fact from a food engineer’s point of view. 

The method of preserving food by the use of different radiations emitted by radioisotopes is known as food irradiation.

There are three types of ionising radiation potentially used to treat food.

  1. Electron beams. 
  2. X rays.
  3. Gamma rays (Occurs from the radioactive decay of (Cesium 137 or Cobalt 60)

The radiation treatment given to food can be classified based on the purpose of irradiation and the type of food irradiated into three types. 

  1. Radappertization is where the food is sterilized(harmful microbes destroyed) by ionizing radiation. Above(10 kGy) eg: Hospital diets, enzyme preparations, prepared meals.
  2. Radurization: It is done to target specific pathogens or reduce the number of microbes. (1 -10 kGy) eg: seafood, raw meat. 
  3. Radicidation: It helps to extend shelf life and inhibit sprouting in vegetables. (up to 1 kGy) eg: Potato, Onion, Garlic. kGy is decimal multiple of SI unit of absorbed dose of ionising radiation and specific energy


It is used in the preservation of fruits and vegetables, seafood, red meat, spices and seasonings, and seeds like alfalfa.

Labeling: The FDA requires that irradiated foods bear the international symbol for irradiation. Look for the Radura symbol along with the statement ” Treated with radiation or treated by radiation on the food label.

Around the world with food technology

Belgium consumes the highest percentage of irradiated food in the world. About 49% of the irradiated food produced is consumed in Belgium. 

Irradiation for life 

Even the intense radiation, when used at the right level, proves beneficial to ensure food safety and extend the shelflife of perishable products. In life, even the hardest situation has its set of advantages. It is up to us how we utilize it. Even the locked down has created a situation where we have plenty of time to spend with our loved ones which were, almost a dream for many of us a couple of weeks ago. 

Antioxidants for health 

 Red guava is a powerhouse of antioxidants with anthocyanins, ascorbic acid or vitamin c and many other phenolic compounds that help us stay healthy and resistant to diseases. It also helps strengthen our nerves. It is perfect to say it is Indian blueberry. 

An interesting piece of information 

  1. The FDA has evaluated the safety of irradiated food for more than 30 years and found the process to be safe.
  2. ‘I think that more consumers would choose irradiated food if they fully understood the process and the results so that they were comfortable with it.’ – says an expert & professor in agriculture and life science.

Hello! To Hurdle Technology

Hurdles are obstacles in life. But today, we will be discussing a different perspective of hurdles.  

Hurdle technology is also called combined preservation or a combination of technologies.

  Now think of the Mario game, which was one of the favourite games, we all played. In every stage, there would be different challenges say a gunfire, or a water jump, or a dragon that super Mario has to overcome, as he proceeds to higher levels, there would be a combination of these obstacles put together to win the stage and go to the next one. 

Now in hurdle technology, the same thing happens, but here we create obstacles for the pathogens in food. Food technologists create an intelligent mix of hurdles to ensure food is safe and shelf-stable with minimal loss in nutrients. 

The different parameters like temperature, water activity, PH, redox potential, preservatives are maintained in such a way that it creates an environment difficult for pathogens to survive.

These hurdles or preservation methods are of three types.

  1. Physical – Heating, Cooling, Drying, Special packaging.
  2. Physicochemical – Ethanol, carbon dioxide, oxygen, salt, organic acids.  
  3. Microbial – Antibiotics, bacteriocins, beneficial microbes.


The microbes respond in different ways. 

   Homeostasis is when the action of microbes is disturbed so that they dont multiply.

  Metabolic exhaustion is when the microbes use all their energy to withstand the unfriendly environment, as a result, they die. 

  A stress reaction is when microbes become resistant and that leads to synthesis of stress shock proteins that helps the microbes to cope with the stressful environment.

Multi target preservation is when different preservation methods with different preservatives are used together instead of one prolonged treatment with only one preservative. For instance a particular microbe becomes resistant to heat, and we need freezing, the addition of acids or other mild techniques.

Application: It is used in the preservation of juices, pineapple slices, pickled fruits, and vegetables, paneer and other products.

The food becomes shelf-stable, taste, texture, flavour, and nutrients in food are retained, due to the use of different preservation methods, yet at a very low intensity.

Around the world with food technology 

Fermented seafood in japan, is preserved using hurdle technology. The main hurdles used are the addition of salt and vinegar. 

 Antioxidants for health

Honey has some beneficial plant compounds or polyphenols that help strengthen our immune system. Add honey to your diet, and stay energetic. It has anti-bacterial and antifungal properties that help in wound healing.

Hurdle technology for life 

We should make an intelligent mix of hope, love, peace, gratitude, positivity, and optimism to win over every difficult situation in life. Gratitude and a positive attitude will make you stronger and more resistant to hard times.

An interesting piece of information

1. Prasadam made out of wheat, jaggery, ghee, cashew, and badam.

 2. Godhi Huggi, a payasam like sweet made with wheat both developed by CFTRI, uses hurdle technology, so it has a shelf life of three months

Grandma’s Technology Of Food

Happy world health day! Do You have any idea who were the first food engineers in the world? Undoubtedly, it was our grannies who discovered food fermentation technology.  

Fermentation is the process of converting carbohydrates to alcohols or organic acids, using microorganisms like yeast or bacteria.

Fermented foods are gaining interest around the world because of the numerous health benefits they offer. 

All the fermented foods are a great source of probiotics and are a part of the traditional cuisines of different countries all over the world. 

What makes probiotics, a healthy choice of food is the age-old fermentation process, and the stains of active gut-friendly bacteria in the culture.

 Probiotics are a group of live beneficial microorganisms that are naturally present in our digestive system.

 Bacteria aren’t all bad.

Our body needs the right balance of good gut-friendly bacteria.

When bad bacteria outnumber good bacteria, illness occurs.

Lactobacillus and bifidobacterium are the most useful bacteria used for fermentation.

 The large scale fermentation process happens inside a fermenter with the help of a suitable nutrient medium under certain favourable conditions.


  1. It improves digestibility and gives the desired flavour and taste to food 

2. It ensures food safety by destroying pathogens in food.

3. It enhances various nutrients in food 

Around the world with food technology

Tapai is a popular dessert with a sweet and acidic taste with a mild alcoholic flavour. Fermenting cooked glutinous rice inside a banana leaf for two days makes a traditional dish, without which the people of Indonesia and Malaysia would never say Selamat Datang.  

Antioxidants for health  

Allicin in garlic is responsible for the antioxidant activity that strengthens the immune system. Add garlic to your diet, and ensure that you stay home, stay safe, and stay healthy.

Instant Rava dhokla recipe, I tried today


1&1/2 cup of Rava

1 cup of water 

1 cup of curd 

1 Tablespoon of oil

a teaspoon of Eno fruit salt 

2-Finely chopped green chilies 

 a teaspoon of turmeric powder 

 a small piece of ginger 

1/2 -Teaspoon of salt 

For tempering add cumin seeds, curry leaves and 2 green chillies, urad dhal, a little oil, and a teaspoon of water. 

Add the curd to the Rava and mix well, then add water, turmeric powder, ginger and green chili that is finely chopped.  

 Allow the batter to rest for 40 minutes. Steam cook for 10 mins and add the tempering, cut into slices and enjoy.

Fermentation for life

In life, many times we may feel that advice that elderly people give us is boring, but when we think about them seriously we will understand there is a lot of wisdom and goodness in their words that heal and improve our life the same way fermented food improves our health.

Old is gold.

An interesting piece of information

Black garlic or fermented garlic has two times the antioxidants present in raw garlic and, this browning is due to Millard’s reaction, which gives a sweet syrupy taste.

Probiotic food helps in the secretion of serotonin, the feel-good hormone.