CALCIUM 5'-RIBONUCLEOTIDES

Calcium 5'-ribonucleotides are calcium salts of natural 5'-ribonucleotides, usually comprising disodium 5’-guanylate (GMP) and disodium 5’-inosinate (IMP), but in the calcium form. 
These compounds occur naturally in animal and plant tissues and are involved in various metabolic processes. 
In food, they are primarily used for their umami-enhancing properties and are often found in combination with monosodium glutamate (MSG) to boost flavor intensity.

CAS Number: 80146-85-6
Synonyms:
Calcium 5'-ribonucleotides,Calcium inosinate and guanylate,Calcium salts of 5’-ribonucleotides
E634,Calcium IMP + GMP,Flavor enhancer E634

Introduction
Calcium 5'-ribonucleotides are important flavor enhancers widely used in the food industry to intensify savory or umami taste. 
They are calcium salts of nucleotides inosine monophosphate (IMP) and guanosine monophosphate (GMP), naturally occurring in many living organisms as key molecules involved in genetic coding and energy metabolism.

The unique taste-enhancing properties of these compounds have made them a valuable additive in processed foods, particularly in Asian cuisine, soups, snacks, and instant meals. 
Their synergistic effect with monosodium glutamate (MSG) amplifies the perception of umami flavor, thus reducing the required quantity of MSG while maintaining or improving taste quality.

Chemical Structure and Properties
Molecular Structure
Calcium 5'-ribonucleotides are formed by calcium ions (Ca²⁺) coordinating with the phosphate groups of 5'-ribonucleotides:
Inosine monophosphate (IMP): A purine nucleotide containing hypoxanthine as its base
Guanosine monophosphate (GMP): A purine nucleotide containing guanine as its base
The general chemical formula varies slightly based on the nucleotide and hydration state, but they share a common ribose sugar and phosphate backbone.

Physical Properties
Appearance: Typically white to off-white crystalline powder
Solubility: Moderately soluble in water; insoluble in organic solvents such as ethanol and ether
Melting Point: Decomposes at temperatures above 200°C
Stability: Stable under dry conditions but can hydrolyze or degrade in aqueous solutions at high temperatures or extreme pH

Chemical Properties
Calcium 5’-ribonucleotides retain the phosphate group of nucleotides, enabling them to bind calcium ions.
Their pKa values vary with the nucleotide base but generally exhibit acidic phosphate groups and basic nitrogenous bases, which contribute to their ionic interactions in solution.
These compounds participate in flavor enhancement primarily due to their ability to activate specific taste receptors on the human tongue, especially synergizing with glutamate receptors.

Occurrence in Nature
IMP and GMP are natural metabolites found in various animal and plant tissues, playing a crucial role in nucleic acid metabolism and energy transfer. 
Foods rich in nucleotides include:
Meat and fish
Mushrooms
Yeast extracts
Certain vegetables like asparagus and peas
Calcium 5'-ribonucleotides, however, are industrially produced salts designed for food additive applications, not directly extracted as pure forms from natural sources.

Production and Synthesis
Industrial Production
The commercial production of calcium 5’-ribonucleotides involves several key steps:
Extraction of Nucleotides: Nucleotides (IMP, GMP) are usually extracted from yeast or other microbial fermentation broths or obtained from hydrolyzed RNA-rich materials.
Purification: Crude nucleotide mixtures are purified through filtration, crystallization, or chromatography to isolate the desired nucleotide monophosphates.
Calcium Salt Formation: The sodium or free acid forms of IMP and GMP are neutralized with calcium hydroxide or calcium carbonate to form the calcium salts.
Drying and Milling: The resultant calcium 5’-ribonucleotide salts are dried and milled into powder for food additive use.

Chemical Synthesis
Chemical synthesis of nucleotides is complex and generally not commercially viable for food additive purposes. 
Biotechnological fermentation and extraction remain the dominant methods.

Mechanism of Flavor Enhancement
Umami Taste and Taste Receptors
Umami, considered the fifth basic taste, is characterized by a savory, brothy, or meaty flavor. 
The human tongue detects umami through specific taste receptors:
T1R1/T1R3 heterodimer: A G-protein coupled receptor responsible for detecting glutamate and nucleotides.
Synergistic effect: Calcium 5’-ribonucleotides (IMP, GMP) enhance the sensitivity of this receptor to glutamate, leading to a stronger umami perception than glutamate alone.

Synergy with MSG
Calcium 5’-ribonucleotides and monosodium glutamate (MSG) act synergistically, meaning their combined effect on flavor enhancement is greater than the sum of their individual effects. 
This allows food manufacturers to use lower amounts of MSG, which is beneficial due to consumer concerns regarding MSG intake.

Applications in the Food Industry
Calcium 5'-ribonucleotides are extensively used as flavor enhancers in various food products to improve taste quality, especially by enhancing the umami flavor profile. 
Their applications include:
Processed meats: Sausages, ham, and meat-based snacks to improve savory notes.
Soups and broths: Instant soups and bouillons benefit from intensified flavor without excessive salt.
Snack foods: Chips, crackers, and savory snacks use calcium 5'-ribonucleotides for balanced taste.
Seasoning blends and sauces: Used in dry mixes and liquid sauces to boost flavor complexity.
Ready meals: Frozen and canned meals containing meat, fish, or vegetables often include these nucleotides for taste enhancement.
Instant noodles: Frequently incorporated into seasoning packets to maximize umami.

SAFETY INFORMATION ABOUT CALCIUM 5'-RIBONUCLEOTIDES

 
First aid measures:
Description of first aid measures:
General advice:
Consult a physician. 
Show this safety data sheet to the doctor in attendance.
Move out of dangerous area:
 
If inhaled:
If breathed in, move person into fresh air. 
If not breathing, give artificial respiration.
Consult a physician.
In case of skin contact:
Take off contaminated clothing and shoes immediately. 
Wash off with soap and plenty of water.
Consult a physician.
 
In case of eye contact:
Rinse thoroughly with plenty of water for at least 15 minutes and consult a physician.
Continue rinsing eyes during transport to hospital.
 
If swallowed:
Do NOT induce vomiting. 
Never give anything by mouth to an unconscious person. 
Rinse mouth with water. 
Consult a physician.
 
Firefighting measures:
Extinguishing media:
Suitable extinguishing media:
Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Special hazards arising from the substance or mixture
Carbon oxides, Nitrogen oxides (NOx), Hydrogen chloride gas
 
Advice for firefighters:
Wear self-contained breathing apparatus for firefighting if necessary.
Accidental release measures:
Personal precautions, protective equipment and emergency procedures
Use personal protective equipment. 
 
Avoid breathing vapours, mist or gas. 
Evacuate personnel to safe areas.
 
Environmental precautions:
Prevent further leakage or spillage if safe to do so.
Do not let product enter drains.
Discharge into the environment must be avoided.
 
Methods and materials for containment and cleaning up:
Soak up with inert absorbent material and dispose of as hazardous waste. 
Keep in suitable, closed containers for disposal.
 
Handling and storage:
Precautions for safe handling:
Avoid inhalation of vapour or mist.
 
Conditions for safe storage, including any incompatibilities:
Keep container tightly closed in a dry and well-ventilated place. 
Containers which are opened must be carefully resealed and kept upright to prevent leakage.
Storage class (TRGS 510): 8A: Combustible, corrosive hazardous materials
 
Exposure controls/personal protection:
Control parameters:
Components with workplace control parameters
Contains no substances with occupational exposure limit values.
Exposure controls:
Appropriate engineering controls:
Handle in accordance with good industrial hygiene and safety practice.
Wash hands before breaks and at the end of workday.
 
Personal protective equipment:
Eye/face protection:
Tightly fitting safety goggles. 
Faceshield (8-inch minimum). 
Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
 
Skin protection:
Handle with gloves. 
Gloves must be inspected prior to use. 
Use proper glove
removal technique (without touching glove's outer surface) to avoid skin contact with this product. 
Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. 
Wash and dry hands.
 
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:Dermatril (KCL 740 / Aldrich Z677272, Size M)
Splash contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:Dermatril (KCL 740 / Aldrich Z677272, Size M)
It should not be construed as offering an approval for any specific use scenario.
 
Body Protection:
Complete suit protecting against chemicals, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.
Respiratory protection:
Where risk assessment shows air-purifying respirators are appropriate use a fullface respirator with multi-purpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. 
 
If the respirator is the sole means of protection, use a full-face supplied air respirator. 
Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).
Control of environmental exposure
Prevent further leakage or spillage if safe to do so. 
Do not let product enter drains.
Discharge into the environment must be avoided.
 
Stability and reactivity:
Chemical stability:
Stable under recommended storage conditions.
Incompatible materials:
Strong oxidizing agents:
Hazardous decomposition products:
Hazardous decomposition products formed under fire conditions. 
Carbon oxides, Nitrogen oxides (NOx), Hydrogen chloride gas.
 
Disposal considerations:
Waste treatment methods:
Product:
Offer surplus and non-recyclable solutions to a licensed disposal company. 
Contact a licensed professional waste disposal service to dispose of this material.
Contaminated packaging:
Dispose of as unused product