NMR spectroscopy and its components and nuclei in meat sciences

 NMR:

It is a nuclear magnetic resonance and used for chemical, physical and biological properties of matter. They have low- and high-resolution NMR. In low resolution, peaks are not properly clear and overlapped with each other that create issues in determine complex structure. In high resolution NMR, peaks are clear. There are two types of NMR nuclei.

1.     NMR Active Nuclei

·       They spin and they are in odd numbers such as 31P, 1H, 13C etc.

2.     NMR Inactive Nuclei

·       They do not spin and they are in even numbers such as 12C

Principle:

The nuclei that have positively charged when magnetic field with wavelength of radio waves is applied then they absorb energy and spin and move from ground state to excited state and then return to ground state with same wavelength and emit the energy and these waves tells about the results.

Components:

·       Magnet (Produce magnetic field)

·       Detector (Detect the signals)

·       Radio Frequency Transmitter

·       Receiver (Show the results)

NMR in Meat Sciences:

31P NMR Nuclei:

Phosphorus 31 nucleus is widely used in NMR spectroscopy because it is naturally available and can be applied in meat sciences for detecting various factors. I.e., species, genotypes, slaughtering and further dietary supplements for determining different meat parameters. Firstly, qualitative studies for comparing post mortem metabolism rates in different muscles. Proved that high rates in porcine muscle as compared to ovine and bovine muscles.

Research compares the post mortem metabolism in 3 different compositions of rabbit muscles. Results shows that the metabolic rates were highest in oxidative muscles and lowest in glycolytic ones. Different parameters were observed i.e., pH (decrease was more significant in glycolytic than oxidative muscles). Temperature Effect was more significant in oxidative than the glycolytic. Thus, conclude that rates increase by raising temperatures. Others factors like genetics, feeding and slaughter procedures were also observed to determine meat quality and post mortem processes. Now a day this technique is an essential tool to determine these factors.

Generally, meat is classified into 3 types Normal, PSE and DFD meats depending upon water holding capacity and pH. PSE results due to short term stress and increases post mortem rates of temperature and glycolysis on the other hand DFD due to long term stress and decreasing glycogen rates. NMR technique will help in easy differentiation between these meats within no time. i.e., 30 min of post mortem thus this will help in predicting the final quality of meat.

31P NMR will measure intracellular pH on the basis of Hesselbach equation other hand NMR spectroscopy will determine both intracellular and extracellular pH. However, limitations lie in determining the pH of post mortem muscles by NMR Spectrometry, as it shows dependency of pk values on two factors ionic strength and temperature.  As these factors are difficult to calculate in post mortem quality of muscles because ionic strengths at different points in post mortem is not clearly known. However, pH determination by 31 phosphorus is more advantageous and non-destructive method as it will take measurements on same tissue location as well.

1H NMR Nuclei:

1H NMR Spectroscopy has high sensitivity but shows difficulty in separating single resonance because of interaction of water in large amount i.e., Biological Systems. However, this technique is beneficial in intact carcasses.

Now a day’s consumers consider meat color its quality and freshness indicator. Meat color is available in 3 myoglobin states. (Deoxymyglobin, Oxymyoglobin and Metmyoglobin). 1 H NMR Spectroscopy is used to determine the auto oxidation of myoglobin in 2 different bovine muscles samples. i.e., Methyl group peak is taken as oxidation indicator. Furthermore, both samples show different rates of auto oxidation.

13C NMR Nuclei:

13C technique is less sensitive as compared to 1H and 31P NMR spectroscopy. 13C NMR has few applications in meat technology but main focus is on muscle glycogen which is considered an important factor in post mortem anaerobic analysis.

 

 

Reasons behind losses of guava and their treatments

 Losses of Guava

Fresh guava keeps at room temperature for one or two days. After 4 days there is 6% weight loss of guava due to room temperature that start causing guava loss and spoilage will start from 5^th day.

Loss due to Diseases:

There are two main diseases such as Algal leaf spot and fungal disease on guava. In algal leaf spot, there are orange color spots on leaves caused by algae due to humid conditions and when it become mature, its color will change into purple. They also attacked branches, stems and guava. In fungal disease, there are patches of dark color on the surface of guava caused by fungus due to wet weather.

Treatments:

For Algae control, use fertilization, Promote air circulation and irrigation. For fungal control, fungicides will be used.

Loss due to Insect pests:

Insect pests are major factor on the production loss of guava. Major insect pests are fruit fly, bark eater caterpillar, fruit borer, white fly and stem borer. Fruit fly cause infestation by laying egg on the surface of fruit that damage the skin and then damage the guava that cause guava loss. Guava losses due to fruit fly are 20-50% in different places but in Punjab 19-41%. Fruit borers cause infestation by laying eggs on the fruit and damage the skin and also damage the guava pulp and the guava infected by fungi and bacteria that cause unpleasant odor and excreta production in guava. Guava losses due to fruit borers are 11-14%. Whiteflies is also called sucking pests that cause infestation by sucking the sap of leaves and secrete the white sticky material which affect the overall appearance of guava plant. It weakens the plant and damage all the fruit. Guava losses due to whiteflies are 80% because of continuous infestation of whiteflies. Caterpillar cause infestation by eating the bark of tree which will die small trees. In large trees, it affects more when more bark is eaten by caterpillar. This causes the drying of branches and leaves which in term causes the fruit to fall down. Guava losses due to caterpillar are 40-50%.

Treatments:

Fruit fly control is very difficult because of high reproduction rate that’s why it can be minimize by insecticides. For fruit borer control, use insecticides and pesticides sprays and cover with polythene bags. For whiteflies control, neem oil and tobacco extract sprays are used. For caterpillar control, use insecticides and fungi such as Aspergillus candidus.

Process of RO plant

RO Plant

Reverse osmosis is a process used to purify contaminated water by passing through different membranes to make it safe for consumption. These steps are performed.

• Ø  Chlorination for disinfection
• Ø  Sand Filtration
• Ø  Carbon Filters
• Ø  Cartridge filters for removal of suspended particles
• Ø  Antiscalant Dosing
• Ø  Hardness reduction by Softening
• Ø  Mineral Dosing
• Ø  Ozonation
• Ø  UV treatment

Step 1 Addition of chlorine:

It is added in raw water to disinfect water and ultimately kill the microbes 4ppm solution is used.

Step 2 Sand Filter:

It removes all the suspended particles if some particles are still there then carbon filters are used. This filter removes the prior added chlorine. If chlorine is not fully removed it will chock the Ro membranes and ultimately destroy them. So, carbon filters are used made up of activated carbon or charcoal. Cartridge filters are of 0.5 microns used to remove the dust and other solid particles from the water. i.e., dust, sand, and dirt further for safety purposes as well. 10 to 15 days’ change is strictly recommended.

Step 3 Antiscalant Dosing:

0.301-micron size of Ro membranes called reverse membranes. Feed Pump takes raw water by the impeller of the high-pressure pump (low to high movement) this impeller will speed up the Reverse osmosis process. Then the water goes in RO membranes having 4 membranes. Before going to RO membranes there is Antiscalant dosing done to prevent it from scaling and rusting issues to the Ro membranes. As water stays in it in 24 hours during processing so to enhance the shelf life of these membranes Antiscalant dosing is performed. Now, this is called product water or Distilled water. Raw water TDS was 550 now DI water has TDS up to 30 to 40. If we consume this water, it will leach out minerals from our body because it has deficiency thus it is hazardous.

Step 4 Mineral Dosing:

 Now, this water is mineral dosed with salts i.e., Calcium Chloride, Magnesium Sulfate, and Sodium Bicarbonate. These 3 salts are added according to national and international standards. Now check TDS concentration it should be up to 120 to 130.

Step 5 Ozonation:

Now ozonation in product tank by ozone diffuser to kill microbes and pungent smell. In this tank, product water is stored and filled in bottles.

Step 6 Bottle Filing:

Bottles used for filling should also be disinfected if issues in bottles disturb the quality of water. Thus, treat bottles with oxonia chemical and then hot water treatment to remove residues of chemical and finally cold water this is done to provide a sudden shock to it to kill microbes. Bottles are filled and further passed through the UV panel. Capper will seal the bottles. If any suspended particles are found during UV observation, then waste the entire product. Thus, it's crucial to properly perform all steps to avoid any mishap. Bottes are filled 100 times then expire. The tank will be filled in 1 hour give 2000-liter product and fill up to 100 bottles in one hour.

Overall Observations:

In the RO plant, there was a proper check and balance. Plant and personal hygiene were up to the mark. Proper machinery setup was installed for purification. Personals and Visitors were following proper SOPs. i.e., Mask, Cap, and Slippers. Thus, Quality and Safety were properly ensured in each processing step which ultimately results in a Quality product (Drinking Water).

 

 

 

 

 

Challenges faced by beverage industry

 

Beverage

A beverage is a drink used for consumption purposes. During the last couple of years’ beverage industry has shown significant growth. i.e. creating a variety of products juices, syrups, milk products, and squashes. Pakistani people consume the non-alcoholic beverage. Among all the beverages soft drinks, fruit juices, coffee, and tea are prevalent in Pakistan. However, there are some issues/ challenges faced by the beverage industry in Pakistan.

Challenges faced by the beverage industry of Pakistan

·       Climate Change and Water Challenges

Climate Change is affecting the beverage industry i.e. Droughts and Natural Disasters. Not accessibility of clean water. However, water is the key ingredient making 90% of the beverage composition. Moreover, water protection, sustainability, efficiency, and conservation are core focuses for beverage industries. This will ultimately reduce their additional cleaning and operational costs. Hence increasing their profit margin.      

·       Growing Demand for Sustainability

Sustainability is a major issue as there is no proper waste treatment, i.e. water used in processing has not had a particular fate. Research has shown that almost 50% of the water waste is produced by the beverage industry. i.e. Bottle washing process. They require large quantities of freshwater for rising and cleaning purposes. Moreover, this water wastage is a debate for a long time. One of the main causes of water wastage is that they did not reuse the water and washing and cleansing require huge expenses of water. Thus by reducing the cost of water and energy, investing this cost in developing new processing technologies would be more beneficial.

·       Health Considerations

Research has shown that now consumers are more aware of health and related disorders. As beverage manufactures are known for adding sugars and artificial sweeteners to their products. This will increase the risk of diabetes, CVDs, and obesity. Moreover, product labeling and compositional requirements are a major concern of consumers. Thus industrialists who are not considering these points will ultimately go in loss and less benefit in the markets. Thus greater taste and creating nutritional alternatives is a challenge for industry growers.

·       Lack of Transparency

Consumer desires to know everything from farm to fork. Industries are lacking transparency means weak bonds and trust issues about brand imaging. Thus manufacturers need to fulfill the expectation of consumers for trust-building and engage more customers. Moreover, large brands like Murree Brewery, Nestle Pakistan, and Shezan International have covered such gaps but local brands are still lacking to create a constant image. This will lead to a lack of transparency across the supply chain as well.

Debate on Plastic

Plastic is a great debate for a long period as it adversely affects the ecosystem and aquatic life as well. Research has shown that around 22 billion water bottles are wasted in each water and most are thrown in water streams i.e. oceans, which release a chemical BPA that causes serious health issues like cancer. Thus beverage industries are shifting to other plastic alternatives to reduce such issues. Green business and eco-friendly packaging systems should be used. Nestle took the initiative to use 100% reusable packaging by 2025. While other beverage industries are still lacking this and using plastic as a packaging material.

·       Authenticity and traceability in beverages

The consumer expects or demands the labeling and source of origins. Beverages are more targeted to food frauds issues. Adulteration or mixing of other undesirable materials which do not match the official standards and labeling and are considered as a non-authentic beverage. Issues are reported in some fruit juices, coffee, tea, and some alcoholic and non-alcoholic beverages. Adulterations from false means possess serious health issues. Thus these points should be taken into considerations.

·       Tackling Allergens Managements

Some allergens are also reported in drinks that cause life-threatening reactions to the allergen person. Moreover, legislation has been passed all over the world to ensure safety by proper labeling of products. Those manufacturers not accompanying these protocols will face serious legal issues. Some common allergens reported are barley, egg protein, gluten, soy lecithin.

·       Meeting Standards and Regulations

Every year many beverages are recalled from the market or banned due to not following proper standards and regulations by officials. Basic reasons are cross-contamination, plastic contamination, adulteration, and allergens addition, and not maintaining proper protocols. Excessive mineral addition is also not required i.e. chlorine, fluorine, iron, etc. They are required in an acceptable range. i.e. Drinking water acceptable chlorine levels are 4 milligrams per liter. Thus to safeguard the quality of beverages manufacturers must ensure hygiene and safety at every production step. Industries that do not follow these regulations will go in loss and bear serious consequences.

How the milling of an apple affects the flavor and color profile of its juice and how we can avoid these effects and give recommendations

Apple Malus domestica is a common fruit consumed widely. It is a rich source of minerals, monosaccharides, fibers, and active compounds i.e. phenolic compounds and vitamin C. Apple juice extraction consists of several processes i.e. preparation, milling, pressing, clarification, filtration, concentration, pasteurization, additives, and finally packaging. Apple juice, cider has higher phenolic contents thus more chances of oxidation.   

Impact on Flavor of Apple Juice

Apple juice contains hundreds of compounds with are directly and indirectly affect the flavor and aroma profile of juices. Containing esters, alcohols, and aldehydes, and other compounds called damasceone, HMF, and furfural. During the milling of apples, undesirable compounds are formed due to enzymatic changes. Unsaturated fatty acids conversation takes place to form aldehydes and alcohols, through a series of lipoxygenase reactions, resulting in C6 compounds being synthesized. (ADH meditated this reaction). Esters are broken down into their successive components. Some compounds like hexanol and butanol provide flavor characteristics in apple juices Although some of the aroma-providing compounds are still unknown. Millard reaction affects the color and flavor of the juice adversely even during storage. Concentrated juices are more prone to undesirable changes if the temperature is above 5C. Poor storage conditions lead to compounds like HMF and furfural. A study has shown that under poor storage conditions of apple juices at 20C, HMF contents are high up to 100 mg per liter. Thus concentrated juices are stored in proper conditions to avoid such circumstances. However, polyphenols impart an astringency effect. Thus excess polyphenols result in undesirable flavor (astringent effect). Astringency and bitterness mainly depend on acidity and cultivar. Bitter apples have more flavan-3-ols contents than non-bitter apples. Juices have less degree of polymerization than fruit pulp itself because procyanidins extraction and solubility decreases for large polymers in juices.  

Avoid

• ·       Millard reaction is inhibited by the addition of Sulphur dioxide. It will effectively stop the very first reaction between the Glucose molecule and charged lysine. Thus as a result further undesirable compounds will not be formed. i.e. HMF, Furfural, Melanoidin
• ·       To prevent the Millard browning storing the juice at lower temperatures. i.e. Rapid cooling of juice is beneficial after heating

Impact on Color of Apple Juice

Apple Juice color relate to PPO on the phenolic contents. The final color of juice depends on the chlorogenic acid. Thus in coupled oxidation reaction secondary oxidation products are formed. Colored oxidation products are extracted from the juice during pressing which increases the golden color of the apple juices. The visual color of juice also depends on light scattering through cloud particles which is considered as turbid juice or hazy juice. Quinones formed during the oxidation of polyphenols are mainly responsible for brown pigments. Research has shown that heating of apple juice forms slight color products possibly due to precipitation bonded quinones and proteins. Thus presence of polyphenol causes turbidity in juices. These include not sediment substances, pectin, hemicellulose, proteins, and solubilized starch. Research has shown that the more phenolic content more the degree of turbidity. Apple primarily contains phenolic acids, catechins, procyanidins, and dihydrochalcones, etc. Moreover, the composition may vary among different cultivars. Complex formation between pectin and procyanidins affects the stability of the apple juice during storage and processing. After pressing apple juice is of pale color and after oxidation of polyphenols color of apple juice changes to yellow-brown color. Chlorogenic acid is mainly called phenolic acid.  However, other compounds like phloridzin and epicatechin impart yellow-orange color in apple juices. A study has shown that these compounds impart 25% of color in juice. Procyanidins are responsible for the other 50% and give a brown color to the apple juices. However, there is a possibility that the chlorogenic acid might break into its further components i.e. caffeic and quinic acid. This will happen in extreme conditions by depectinizing enzymes. Its level may fall up to 10 mg per liter which is undesirable.

Avoid

• ·            Some undesirable color changes may be reduced by the addition of salt i.e. Ascorbate
• ·            Reducing the temperature below 2°C prevents the activity of polyphenol oxidase PPO enzyme
• ·           High Acidic conditions would also be beneficial as they will lower the pH up to 3
• ·      Reducing the substrate concentration will also be helpful. i.e. Tanning process will mask the active sides of procyanidin thus reducing its activity
• ·          Formation of big size polymers i.e. Polymerization
• ·       Oxidized products removal which eventually causing color changes. i.e. by adsorption onto the pulp
• ·       Avoid procyanidins to produce insoluble compounds by adding enzymes. i.e. amylolytic and pectinolytic. Thus haziness or cloudiness is avoided in the juice and thus forms a clear apple juice

Recommendation

In order to avoid the non-enzymatic browning (PPO polyphenol oxidases) different methods are proved beneficial i.e. chelating agents react with metal thus forming stable and water soluble compounds (EDTA, Carboxylic acid), Acidulates that will lower the pH (Citric and Malic acids). An antioxidant will prevent binding the oxygen (Ascorbic Acid and Maclurin) etc. Moreover, using unripe grape and lemon juice is also helpful in preventing undesirable reactions and complex brown pigments.