DESC:TECHNICAL FIELD
The present technical disclosure relates generally to the formulation for delaying oxidation of oil and fats during frying. In particular, the present disclosure relates to the plant-based formulation which improves the stability of the frying oils and fats.

BACKGROUND
Oil and fats are the most important components of our daily diet. Oil and fats when encountered by moist air at room temperature ultimately undergo oxidation and hydrolysis reactions which cause them to turn rancid, acquiring a characteristic disagreeable odor. Oils with higher degree of unsaturation are more prone to oxidation. The oxidation of unsaturated fatty acids makes oils unacceptable to consumers. Oxidation causes food to lose flavor, quality, color and can even cause foods to become toxic. This mostly occurs when oils are in direct contact with heat, light, oxygen, and metals. The oxidation of oils leads to the formation of hydro peroxides and organic compounds such as aldehydes, ketones and acids which can cause undesirable odor and flavor.

In order to prevent this oxidation many antioxidants are used which scavenges free radicals, thereby inhibiting oxidation of oil. These antioxidants are also added to the daily life edible oils and fats for the purpose of prolonging shelf life and inhibiting oxidative rancidity of the oil and fats. In the prior art different types of the antioxidant were used to increase the shelf life of the oil. They are classified as oxygen scavengers, free radical scavengers, enzyme inhibitors and the like.

The antioxidant can be synthetic antioxidants or the natural antioxidant. Synthetic antioxidants like butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), propyl gallate (PG) and tert-butyl hydroquinone (TBHQ) are the ones commonly used in edible oils to provide shelf life to refined edible oils. These synthetic antioxidants have been the conventional products in the food antioxidant market due to the advantages of high yield, low price, and strong oxidation resistance. However, these synthetic antioxidants come with many disadvantages like their volatility and tendency to decompose at higher temperature making them less suitable for deep fat or oil fried foods. A major drawback of using these antioxidants is that its effectiveness only lasts for 4 - 5 hours while frying, it requires frequent additions of these during frying process. Prolonged exposure to high doses of TBHQ, BHA, and the like can be carcinogenic and affect the immune system. These synthetic antioxidants are banned in some countries due to adverse health issues.

With a growing shift towards clean label ingredients and with increased awareness among customers about the side effects of synthetic additives and health issues caused due to consumption of the synthetic additives; there is a rise in demand for natural food ingredients. Therefore, the search for safer, healthier, and green antioxidants is a trend in the field of food processing. In recent years, the use of natural antioxidants has attracted a great deal of attention from food technologists.

As natural antioxidants are extracted from plants, they are safe for the environment as well as to human being. The natural antioxidant has attracted extensive attention due to its good oxidation resistance and safety, and it shows an optimistic development prospect.

Conventionally, most research work has focused on the antioxidant properties of the individual components of natural antioxidants, but there is lack of research on the formulation with more than one plant-based antioxidant which shows the better antioxidant property with the synergistic effect of each component.

Therefore, there is a need to provide a plant-based formulation that can effectively control the oxidation of vegetable oil during frying and does not decompose itself into any harmful compounds.

OBJECTS
Some of the objects of the present technical disclosure, which at least one embodiment herein satisfies, are as follows:

An object of the present technical disclosure is to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

Another object of the present technical disclosure is to provide a plant-based natural antioxidant formulation which increases the frying stability of vegetable oil.

Still another object of the present technical disclosure is to provide the optimized plant-based antioxidant formulation which is suitable for a wide range of vegetable oils.

Still another object of the present technical disclosure is to provide plant-based antioxidant formulation which ameliorates the problems associated with the prior art antioxidant formulations.

Other objects and advantages of the present technical disclosure will be more apparent from the following description, which is not intended to limit the scope of the present technical disclosure.

SUMMARY
This summary is provided to introduce the plant-based formulation as an antioxidant /thermal stabilizer to prevent the oxidation of the vegetable oil during frying. Specifically, the present invention relates to novel and natural antioxidant formulation which is suitable for a wide range of vegetable oils. The summary is neither intended to identify essential features of the present technical disclosure nor is it intended for use in determining or limiting the scope of the present technical disclosure.

In an embodiment of the present technical disclosure, a novel antioxidant formulation prepared from natural active ingredients in the form of plant extracts, which offers safer and healthier oil preservation is provided. The formulation is optimized to determine the effective concentration of these extract which shows the synergistic antioxidant activity.

The formulation of the present invention is a combination of rosemary extract, tocopherols, lecithin, and ascorbic acid in an effective concentration that aids in increasing the frying stability of vegetable oil. The resultant formulation when added to frying oil slows down the oxidation process and, they do not breakdown into unsafe products during frying. The resultant formulation significantly enhanced the frying stability of oil during deep fat frying.

According to this invention, there is provided a plant-based formulation for enhancing frying stability of a vegetable oil; said formulation comprises:
a) rosemary extracts in an amount of 40 to 60% w/w;
b) rosemary oleoresin in an amount of 5 to 10% w/w;
c) lecithin in an amount of 2 to 10% w/w;
d) ascorbic acid an amount of 1 to 5% w/w;
e) mixed Tocopherol an amount of 8 to 15% w/w; and
f) glycerides an amount of 45 to 70% w/w.

In at least an embodiment, rosemary extracts comprises 50% carnosic acid

In at least an embodiment, rosemary oleoresin comprises 8% carnosic acid.

In at least an embodiment, the formulation comprises 2 to 6 % of 50% carnosic acid and 12 to 18% of 8% carnosic acid.

In at least an embodiment, the formulation comprises 4 to 5 % of 50% carnosic acid and 15 to 16% of 8% carnosic acid.

In at least an embodiment, the amount of lecithin in an amount of 6 to 7% w/w;

In at least an embodiment, the amount of ascorbic acid an amount of 3 to 4% w/w.

In at least an embodiment, the amount of mixed Tocopherol is 10 to 11%w/w.

In at least an embodiment, the glycerides comprise mono and di glycerides in an amount of 55 to 65% w/w.

According to this invention, there is provided a process for preparing a plant-based formulation, wherein said process comprises the following steps:
i. taking rosemary oleoresin with 8% carnosic acid in a vessel and adding rosemary extract with 50.0% carnosic acid to said vessel followed by mixing thoroughly with an agitator rod to obtain a mixture;
ii. adding ascorbic acid and a portion of mono and diglycerides to said mixture followed by mixing to obtain a blend;
iii. transferring said blend to a ball mill to grind and obtain a second mixture having particle size in the range of 200 to 250 micro meter;
iv. adding lecithin to said second mixture followed by blended for 30 to 90 minutes to obtain a mass;
v. adding mixed tocopherol and a portion of mono and diglycerides followed by mixing to obtain a pre-formulation; and
vi. passing said formulation through a homogenizer to obtain the formulation.

DETAILED DESCRIPTION
The invention will now be described with embodiments which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.

One or more embodiments are provided so as to thoroughly and fully convey the scope of the present invention to the person skilled in the art. Numerous details, are set forth, relating to specific processes, and methods, to provide a complete understanding of embodiments of the present invention. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present invention. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present invention, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present invention. As used in the present invention, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present invention is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.

Ratios, concentrations, amounts, and other numerical data may be presented herein in a range format. It is to be understood that such range format is used merely for convenience and brevity and should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a concentration range of about 0.01-10 % should be interpreted to include not only the explicitly recited limits of about 0.01% to about 10% but also to include sub-ranges, such as 1-9%, 1.5-9.5% and so forth, as well as individual amounts, including fractional amounts, within the specified ranges, such as 1.25%, and 5.55% for example.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure, the preferred methods, and materials are now described.

The various embodiments of the present disclosure describe a formulation prepared from the plant extract which is used as an antioxidant and thermal stabilizer.

The conventional synthetic antioxidant used in vegetable oil are effective only for 4 - 5 hours while frying, it requires frequent additions of these antioxidants during frying process. Prolonged exposure to high doses of the conventional synthetic antioxidant can be carcinogenic and affect the immune system.

In an aspect of the present disclosure, in order to overcome the above referenced problems and to provide various advantages elaborated in the subsequent section, a plant-based antioxidant formulation is disclosed.
In one of the embodiments, the present disclosure disclosed the plant-based antioxidant formulation comprising rosemary extract along with the source of tocopherols, lecithin, and ascorbic acid in a particular concentration.

In one of the embodiments, the formulation composition is:
• Rosemary extract (50% carnosic acid) – 4.20%
• Rosemary oleoresin (8% carnosic acid) – 15.40%
• Lecithin – 6.40%
• Ascorbic acid -3.20%
• Mixed Tocopherol- 10.80%
• Mono and di glycerides -60.0%
The excipient used is mono and diglycerides. Mono and diglycerides have GMP status as per CODEX and FSSAI, when used in the respective food category of Fats and oils.

Extending shelf life of foods by replacement of synthetic antioxidants with sustainable natural products like essential oils and plant extracts have attained wide spread interest as a green technology deprived from any toxicity. The invention is a combination of naturally proven antioxidants at certain concentration is found to have synergetic effect in enhancing the frying stability of vegetable oil. The combination is suitable for broad range of oil including the saturated, mono unsaturated and poly unsaturated fatty acids for deep fat frying. In order to optimize a composition, the ingredients were analyzed individually and in several combinations. Several trials were done to optimize the ingredients in the formulation. The ingredients which gave better antioxidant activity in oil and whose synergetic effect contributed for enhancing the frying stability on vegetable oil were then selected. The formulation includes rosemary extracts as the major ingredient followed by mixed tocopherols, soy lecithin and ascorbic acid.

Rosemary extract is a natural antioxidant used as food additive. It is extracted from the leaves and flowers of Rosmarinus officinalis L. In the current invention’s formulation, the inventors have used Rosemary extract with 50% carnosic acid and Rosemary oleoresin with 8.0% carnosic acid content. The active components for antioxidant property in rosemary extract are carnosic acid (CA), carnosol, rosmarinic acid and rosmanol which play a significant role in delaying the degradation/oxidation of food. The extract plays a vital role in controlling the lipid oxidation during storage and frying. It delays the formation of secondary oxidation products like aldehydes and ketones during deep fat frying. The extract has another advantage that on heating it degrades to phenolic compounds which accounts for the frying stability. On heating, carnosic acid is converted to carnosol and subsequently, rosmanol, epirosmanol and 7-methylepirosmanol, which are phenolic compounds that further remain active as antioxidants scavenging the free radicals during frying (5). That is the degradation products of rosemary extracts are non-toxic unlike other hetero carbons forms produced during deep frying when using synthetic antioxidants like TBHQ, BHT, BHA or Propyl gallate. Rosemary extracts are also an approved additive in different food categories in various countries like European Union, Australia and New Zealand.

The natural antioxidant for vegetable oil is able to provide better thermal stability when compared with the common synthetic antioxidants. These stabilizers for frying are a composite of natural active ingredients in the form of plant extracts, which offers sustainable, safer and healthier oil preservation. The combination of rosemary extract with mixed tocopherol was found to be very effective in controlling the reaction chain. There are literature supporting our research that combinations of ascorbic acid, green tea and mixed tocopherols attributed to higher stability (6). It was observed that a synergistic effect of multiple compounds resulted for the increase in thermal stability in vegetable oil during deep fat frying. These antioxidants when used as a combination gave better result than any single antioxidant. Antioxidants like rosemary extract, ascorbic acid and mixed tocopherols have high frying stability when compared to the synthetic antioxidant TBHQ, which is reported to degrade even below 1800C. Other than the antioxidant property, these bio-active compounds act as immunity boosters without any health complications.

According to this invention, there is disclosed a method of preparation of the formulation of this invention as detailed below.
Method of preparation: Current Invention’s Formulation (Formulation A) Initially, rosemary oleoresin with 8% carnosic acid is taken in vessel and to this; rosemary extract with 50.0% carnosic acid is added and mixed thoroughly with an agitator rod to obtain a lump free uniform paste. To this mixture ascorbic acid and a quarter portions of mono and diglyceride (1/4th of the total) is added. This blend is then passed through a bench top ball mill that rotates at a constant speed. Rotating in the horizontal axis ball mill ease coarse grinding and hence reduces the particle size of the material put inside. Stainless steel balls with a diameter of 1.4.0cm are added along with the raw materials. The ratio of balls to material is 1:1, both balls and ingredients occupying about half a portion of the cylindrical vessel. High pressure is generated inside the ball mill by the collision of balls, thereby allowing coarse grinding within the container. This method has the advantage that the reduced particle size of rosemary powder and ascorbic acid increases the solubility of the blend in vegetable oil. The process is continued for an hour . Lecithin is then added to the mixture and is again blended for an hour at constant rpm. Lecithin is a proven emulsifier which also contributes to the antioxidant property along with the other ingredients. Addition of lecithin largely helps in stabilizing the formulation. Next, mixed tocopherol is added as per the ratio and the remaining portion of mono and diglycerides is added finally. The whole ingredients are then allowed to blend for 30 minutes. The formulation is then removed and passed through a high pressure homogenizer (Gea Niro Soavi- Panda plus- Italy) in order to enhance the product nature and stability. Homogenization also reduces the emulsion size. It is then transferred to storage containers.

The other formulations tried included the below:

Formulation B- A blend containing Rosemary extract 50%CA* (4.2%), Rosemary oleoresin 8% CA (15.4%), Lecithin (6.4%), Mixed tocopherols (10.8%) (Without Ascorbic acid)

Formulation C- A blend containing Rosemary extract 50%CA* (4.2%), Rosemary oleoresin 8% CA (15.4%), Lecithin (6.4%), Ascorbic acid (3.2%) (Without Mixed tocopherols)

Formulation D- A blend containing Rosemary extract 50%CA* (4.2%), Rosemary oleoresin 8% CA (15.4%), Lecithin (6.4%), Mixed tocopherols (10.8%) and citric acid (3.2%) (Without ascorbic acid but replaced with citric acid)
* CA- Carnosic Acid
The excipient used is mono and diglycerides in all the formulations and is added accordingly to adjust the entire content to obtain 100.0%

Preparation of Formulation B
Initially rosemary oleoresin with 8% carnosic acid is taken in vessel and to it; rosemary extract with 50.0% carnosic acid is added and mixed thoroughly with an agitator rod to obtain a lump free uniform paste. To this mixture quarter portions of mono and diglyceride (1/4th of the total) is added. This blend is then passed through a bench top ball mill that rotates at a constant speed. Stainless steel balls with a diameter of 1.4cm are added along with the raw material. The ratio of balls to material was 1:1. The process is continued for an hour. Lecithin is then added to the mixture and is again blended for an hour at constant rpm. Next, mixed tocopherol is added as per the ratio and the remaining portion of mono and diglycerides is added finally and blended for another 30.o minutes. The formulation is then removed and passed through a high pressure homogenizer. It is then transferred to storage containers.

Preparation of Formulation C
Initially rosemary oleoresin with 8% carnosic acid is taken in vessel and to it; rosemary extract with 50.0% carnosic acid is added and mixed thoroughly with an agitator rod to obtain a lump free uniform paste. To this mixture ascorbic acid and quarter portions of mono and diglyceride (1/4th of the total) is added. This blend is then passed through a bench top ball mill that rotates at a constant speed. Stainless steel balls with a diameter of 1.4cm are added along with the raw material. The ratio of balls to material was 1:1. The process is continued for an hour. Lecithin is then added to the mixture and is again blended for an hour at constant rpm. The remaining portion of mono and diglycerides is added finally and blended for another 30.0 minutes. The formulation is then removed and passed through a high pressure homogenizer. It is then transferred to storage containers.

Preparation of Formulation D
Initially rosemary oleoresin with 8% carnosic acid is taken in vessel and to it; rosemary extract with 50.0% carnosic acid is added and mixed thoroughly with an agitator rod to obtain a lump free uniform paste. To this mixture citric acid and quarter portions of mono and diglyceride (1/4th of the total) is added. This blend is then passed through a bench top ball mill that rotates at a constant speed. Stainless steel balls with a diameter of 1.4cm are added along with the raw material. The ratio of balls to material was 1:1. The process is continued for an hour. Lecithin is then added to the mixture and is again blended for an hour at constant rpm. Mixed tocopherols and the remaining portion of mono and diglycerides is added finally and blended for another 30.0 minutes. The formulation is then removed and passed through a high pressure homogenizer. It is then transferred to storage containers.

Frying study
As the antioxidant/ thermal stabilizer, the current invention is helpful in stabilizing the frying oil, frying study was planned in various types of vegetable oil, based on their fatty acid composition. The global consumption of vegetable oil reveals that, palm olein oil accounts for the major share in frying industry. Palm olein oil is generally considered to have both saturated and unsaturated fatty acids and is the most widely consumed oil for frying followed by various other oils. Hence the frying trial was conducted with Refined Bleached and Deodorized (RBD) palm olein oil (PO). Another vegetable oil selected was sunflower oil (SFO), being unsaturated oil the trial was conducted with the same. A positive control of vegetable oil with synthetic antioxidant TBHQ was done simultaneously. TBHQ was selected due to its acceptance in refineries and large scale manufacturing units. It was also found that TBHQ was the most common antioxidant used as per regulations like CODEX, FSSAI and EU. Other antioxidants like BHA, BHT or propyl gallate can also be used. The maximum concentration of synthetic antioxidant that can be used in vegetable oil is 200mg/kg. It can be used in single or in combination with one another but strictly the limit is restricted to 200mg/kg ie: 200ppm only.

Materials: TBHQ, French fries, RBD palm olein oil and refined sunflower oil were procured directly from the manufacturer. Both oils were analysed for its basic quality parameters (peroxide value less than 2meqO2/Kg oil) and also checked for the presence of any synthetic antioxidant. Deep fryers with temperature controller (Akasa deep fryers, Akasa International, New Delhi), Testo 270 (Testo India Pvt. Ltd. Pune), electronic balance (Mettler Toledo, USA), Rancimat (Metrohm, USA) and glass wares were the other materials used for the study. All the reagents used are analytical grade, purchased from authorised manufacturers.

Frying Methodology:
The frying process is done by frying suitable product (french fries) in an electric fryer having a capacity of 7.0 liters at controlled temperature
About 4.0 liters of vegetable oil was filled in chamber.
Respective antioxidants (as given above) were added to the oil before the onset of frying. The oils in the chambers were allowed to attain a temperature of 1800C.
200.0g of French fries were fried in each batch for a continuous cycle. Each cycle was for 6 min, 4 minute frying and 2 minutes to attain the temperature.
Continuous frying was carried until TPC of oil reached 20.0%.

Parameters analysed:
The quality parameters of frying oil namely TPC, Free Fatty Acid, Peroxide value, Totox Value and para-anisidine value were analyzed as per AOCS methods, at periodic intervals to check its degradation. TPC content was analyzed using calibrated equipment – TESTO 270. Oxidative stability or extend of degradation of the fried oil were further analyzed using Rancimat instrument - Metrohm 743 following the AOCS method. All the parameters analysed where in triplicate determinants and the mean was calculated.

Experiment 1 with RBD Palmolein oil:
Here the experiment was done with RBD Palm olein oil as the frying medium with the below antioxidant/ formulations.
1- 200ppm TBHQ
2- 200ppm current invention’s formulation (Formulation A)
3- 200ppm Formulation B
4- 200ppm Formulation C
5- 200ppm Formulation D
Experiment 2 with Sunflower oil:
Here the experiment was done with Refined sunflower oil as the frying medium with the below antioxidant/formulations.
1- 200ppm TBHQ
2- 200ppm current invention’s formulation (Formulation A)
3- 200ppm Formulation B
4- 200ppm Formulation C
5- 200ppm Formulation D
Result and Discussion
There are a number of complex series of reactions occurring in fats and oils during deep fat frying. This is mainly due to hydrolysis, oxidation of oil due to the presence of moisture in the food fried and a greater extend of chemical reactions caused due to the polymerization of vegetable oils. The quality of the fried food depends to a larger extend on the quality of the oil used for frying. There are both chemical and organoleptic changes in the fried product, when a poor quality of oil is used in frying.

The formulations were compared with the most widely used synthetic antioxidant TBHQ at the same concentration. The purpose of trial with formulations B, C and D was to optimize the effect of each minor component like ascorbic acid and mixed tocopherols. The study could also further confirm the synergetic mechanism which attributed for the frying stability. As rosemary extracts are the proven natural ingredient with a high potential of antioxidant properties, the concentration of this ingredient was kept constant in all the formulation. Another ingredient lecithin have a crucial role in stabilizing the emulsion hence the study did not alter the concentration of lecithins in the formulations.

Formulation A, the current invention’s formulation contains rosemary extracts, soy lecithin, ascorbic acid and mixed tocopherols as ingredients. Formulation B was made without ascorbic acid so as to find the effect of ascorbic acid in current invention’s formulation. Next, formulation C was made without mixed tocopherols so that it can prove the efficacy in the experiments. Finally, formulation D was made with citric acid replacing the ascorbic acid. This formulation on frying studies can clearly demonstrate the synergetic effect and inevitable presence of ascorbic acid –mixed tocopherol combination in the formulations.

Total Polar Compounds (TPC)
TPC, the total polar compounds in oil are the major quality parameter that is analyzed during frying. It is also an easy parameter that can be observed during frying. TPC in oil indicates the extend of total degradation of oil when it is used for deep fat frying. The TPC of oils were measured using the hand Testo instrument. TPC of oils is measured while at frying. This method is globally followed due to its ease of application and effective result. Hence many countries have set a fixed limit to monitor the frying oil quality, that the frying oil should not cross TPC above 25.0%. The formulation proved to be better in frying stability when compared with same concentration of the synthetic antioxidant TBHQ during the frying trial. Oils were checked each hour for TPC content.
The result proved that the current invention’s formulation could effectively control the Total Polar Compounds; hence a cut off of frying time was fixed when the TPC crossed 20.0% in any of the oil. When TPC crossed 20.0 in oil, the oil will be darker indicating the onset of degradation on continuous frying. Hence further frying was stopped beyond this limit. The data of frying studies of antioxidants –in RBD Palm olein oil is described below.
It can be observed that, current invention’s formulation at 200 ppm when added to RBD Palm olein oil gave remarkable effects during deep fat frying when compared with a control RBD Palm olein oil with 200 ppm TBHQ. Frying was carried for 10:00hrs at 1800C. When the TBHQ added oil crossed 20.5 in % TPC, RBD palm olein oil with current invention’s formulation reached only 15.5 in TPC content, which prove the effectiveness of antioxidant. The higher value of TPC shows the higher degree of oil oxidation which reflects to the decomposition of oil on frying at high temperature.
On a comparative basis it can be clearly seen that formulation C without mixed tocopherol attained a TPC value of 18.0 at 10:00 hrs of frying, whereas the formulation B with ascorbic acid reached 16.5 in TPC. From the results it is also very clear that the percentage of ascorbic acid did not play significant effect in controlling the TPC value in oil which can be related with the results of formulation D which is a citric acid added blend but contains mixed tocopherol. Formulation D reached only to a TPC value of 16.5% at 10:00 hrs which shows the presence of mixed tocopherol in the formulations helped in controlling the TPC.

The result of current invention’s formulation added sunflower oil also showed a same trend. Here the oil with 200 ppm TBHQ reached a % TPC cut of limit of 20.0 after frying for 8:00 hrs, were as the sunflower oil with current invention’s formulation attained only 16 in TPC content even after 8:00hrs. . Both Formulation B and Formulation D reached a TPC content of 17.0%, but in Formulation C the antioxidant blend without mixed tocopherol attained 18.0% after 8:00 hrs of frying. But the TPC content of all formulations were lesser than that of the TBHQ added oil. This shows the effective control of antioxidant formulation in vegetable oils and the role of mixed tocopherols in controlling TPC.
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Table:1 Total Polar Content during frying in RBD Palm olein oil
TOTAL POLAR COMPOUNDS (%)

Sample Frying Time in Hours
0 1 2 3 4 5 6 7 8 9 10
PO + 200ppm TBHQ 7.5 10.0 11.5 12.5 13.5 14.5 16.0 17.0 18.0 18.5 20.5
PO + 200ppm Current Invention’s Formulation (Formulation A) 8.5 11.0 11.5 12.0 12.5 13.0 13.5 14.0 14.5 15.5 15.5
PO + 200ppm Formulation B 8.5 11.0 11.5 12.0 13.0 13.5 14.0 14.5 15.5 16.0 16.5
PO + 200ppm Formulation C 8.5 11.0 12.0 12.5 13.0 13.5 14.5 16.0 17.0 17.5 18.0
PO + 200ppm Formulation D 8.5 11.0 11.5 12.0 13.0 13.5 14.0 14.5 15.5 16.0 16.5

Table:2 Total Polar Content during frying in Sunflower oil
TOTAL POLAR COMPOUNDS (%)

Sample Frying Time in Hours
0 1 2 3 4 5 6 7 8
SFO + 200ppm TBHQ 8.5 11.0 12.0 13.0 14.0 15.5 16.5 18.5 20.0
SFO + 200ppm Current Invention’s Formulation (Formulation A) 9.0 11.5 12.0 13.0 13.5 14.0 14.5 15.0 16.0
SFO + 200ppm Formulation B 9.0 11.5 12.0 12.5 13.5 14.0 15.0 16.0 17.0
SFO +200ppm Formulation C 9.0 11.5 12.5 13.0 14.0 14.5 15.5 16.5 18.0
SFO + 200ppm Formulation D 9.0 11.5 12.0 12.5 13.5 14.0 15.0 16.0 17.0

Free fatty acids (FFA)
Free fatty acids (FFA) are one of the quality indices for the frying oil. The presence of free fatty acids (FFAs) in oil is also an indication of insufficient processing, lipase activity, or other hydrolytic actions. FFA is produced in oil during heating by hydrolysis reaction as a result of the moisture released by the products fried. The level of FFA in oils depends on the frying time, temperature and moisture of the food during frying. FFA are less stable than neutral oil and more prone to oxidation. Hence, it is a key feature linked with the quality of oil during frying. The maximum specified limit for FFA in frying oil is 1.0 and is expressed in percentage.
The results of FFA with 200ppm current invention’s formulation were found to be similar to that of TBHQ in both RBD palm olein oil and Sunflower oil . A remarkable difference was not noted in the FFA content which always fell within the quality limit of the respective oil. But looking deep into each, it can be seen that the presence of ascorbic acid and citric acid contributed for an increase in FFA values in formulations eventhough the values were within the limits. As FFA is very crucial in determining the quality of oil, increaseing the concentration of ascorbic acid beyond the limit used can reflect to an increased acid content that can degrade the oil.

Table:3 FFA of oil during frying in RBD Palm olein oil
FREE FATTY ACID VALUE (%)

Sample Frying Time in Hours
0 2 4 6 8 10
PO + 200ppm TBHQ 0.14 0.24 0.33 0.45 0.56 0.60
PO + 200ppm Current Invention’s Formulation (Formulation A) 0.14 0.22 0.34 0.44 0.55 0.62
PO + 200ppm Formulation B 0.14 0.22 0.33 0.44 0.54 0.61
PO + 200ppm Formulation C 0.14 0.23 0.34 0.44 0.56 0.62
PO + 200ppm Formulation D 0.14 0.23 0.35 0.45 0.55 0.63

Table:4 FFA of oil during frying in Sunflower oil
FREE FATTY ACID VALUE (%)

Sample Frying Time in Hours
0 2 4 6 8
SFO + 200ppm TBHQ 0.05 0.07 0.11 0.14 0.16
SFO + 200ppm Current Invention’s Formulation (Formulation A) 0.05 0.08 0.11 0.13 0.16
SFO + 200ppm Formulation B 0.05 0.07 0.11 0.12 0.15
SFO + 200ppm Formulation C 0.05 0.08 0.12 0.13 0.16
SFO + 200ppm Formulation D 0.05 0.07 0.12 0.14 0.17

Peroxide value (PV)
Peroxide value (PV) is yet other quality parameters for vegetable oils which indicate the rancidity. It is the amount of peroxide oxygen in oil and is hence directly related to the oxidative status of frying oil. It is expressed as mille equivalence of oxygen per kg of oil. Oxidation of oil is happening during the heating of oils. The amount of peroxides indicates the degree of primary oxidation and therefore is linked to the rancidity. The steady increase in peroxide indicates the formation of hydro peroxides during the oxidation of oils or fats.
Here in our study it was noted that the peroxide value of the control oil with TBHQ in both palm olein oil and sunflower oil had more peroxide content than the oil treated with current invention’s formulation.
The importance of ascorbic acid in the blend is very clearly observed from the results of peroxide value as the formulation B, the current invention’s formulation attained a peroxide content of only 2.48meq/kg after 10:00 hrs of frying in palm olein oil. Almost a close result (2.63meq/kg) was observed with formulation C which contains ascorbic acid. The result of formulation D which is a blend with mixed tocopherol and citric acid had a slight higher Pv which is 2.78meq/kg and formulation B, the blend without ascorbic acid that is the combination of rosemary extract and tocopherol reached to peroxide value of 2.88meq/kg (10:00 hrs) a significantly higher range but still the values were lesser than that of TBHQ added oil. This strongly supports the effect of natural antioxidant in controlling the frying stability with perspective to peroxide control in oil than the synthetic antioxidant.
The pattern was almost similar in frying conducted with sunflower oil also. The Formulations B, C and D reached to peroxide content of 3.79meq/kg, 2.80meq/kg and 3.54meq/kg respectively after 8:0 hrs. The results of current invention’s formulation -A was comparable to that of formulation C, indicating the presence of ascorbic acid in both blends, for the lower peroxide content in them. Here the peroxide content was low as 2.39meq/kg in blend with current invention’s formulation but TBHQ added oil reached to 4.13meq/kg on 8:00 hrs of frying. Even though ascorbic acid did not show effect in controlling the FFA values, its mechanism in controlling the peroxide formation was very well noticed.

Table:5 Peroxide value of oil during frying in RBD Palm olein oil
PEROXIDE VALUE (MEQ O2/KG)

Sample Frying Time in Hours
0 2 4 6 8 10
PO + 200ppm TBHQ 1.03 2.39 3.04 3.42 2.59 3.49
PO + 200ppm Current Invention’s Formulation (Formulation A) 1.03 0.9 1.44 1.97 1.3 2.48
PO + 200ppm Formulation B 1.03 1.63 2.12 2.54 1.93 2.88
PO + 200ppm Formulation C 1.03 1.18 1.87 2.28 1.70 2.63
PO + 200ppm Formulation D 1.03 1.52 2.04 2.42 1.87 2.78

Table:6 Peroxide value of oil during frying in Sunflower oil
PEROXIDE VALUE (MEQ O2/KG)

Sample Frying Time in Hours
0 2 4 6 8
SFO + 200ppm TBHQ 0.21 1.89 3.16 4.1 4.13
SFO + 200ppm Current Invention’s Formulation (Formulation A) 0.21 1.26 1.32 2.27 2.39
SFO + 200ppm Formulation B 0.21 1.73 2.87 3.63 3.79
SFO + 200ppm Formulation C 0.21 1.39 1.75 2.81 2.80
SFO + 200ppm Formulation D 0.21 1.61 2.53 3.46 3.54

p-Anisidine value
Lipid oxidation is one of the important causes of spoilage in vegetable oils. Hydroperoxides, the major initial reaction products of lipid oxidation, which are quantified by determining the peroxide value content are highly unstable and decompose spontaneously to form other compounds such as aldehydes, ketones, alcohols, acids, hydrocarbons, etc. These secondary carbonyl breakdown products causing rancidity are mainly measured by the p-anisidine value.
The secondary oxidative degraded products have a major role in extending the shelf life of oil during frying. TBHQ the synthetic antioxidant is reported to be unstable at high temperature and on prolonged heating of oil. This does not provide any effect towards the frying stability of the oil. Whereas the natural antioxidant formulation is capable of withstanding the higher temperature and significantly controls the vegetable oil during continuous frying at 1800C for even more than 10:0 hrs. From the table it can be noted that there is a continual increase in p-anisidine value for all the samples. Refined palm olein oil with current invention’s formulation showed less p-anisidine value compared to the TBHQ added oil. The secondary oxidation products were more random in sunflower oil in which the TBHQ added sample crossed 98.61 in 4:00hrs of frying mean time the sample with current invention’s formulation attained a value of 49.82 in the 4:00 hrs. This can further add to the statement that the current invention’s formulation very effectively plays a role in controlling the degradation product in oil.

Table:7 p-Anisidine value during frying in Palm olein oil
p-ANISIDINE VALUE

Sample Frying Time in Hours
0 2 4 6 8 10
PO + 200ppm TBHQ 3.02 41.49 62.96 70.05 70.64 72.5
PO + 200ppm Current Invention’s Formulation (Formulation A) 3.02 19.06 30.55 37.39 49.22 50.4
PO + 200ppm Formulation B 3.02 27.35 42.24 54.39 60.64 67.81
PO + 200ppm Formulation C 3.02 22.13 36.39 41.84 52.03 54.71
PO + 200ppm Formulation D 3.02 23.08 59.48 64.76 65.17 68.49

Table:8 p-Anisidine value during frying in Sunflower oil
p-ANISIDINE VALUE

Sample Frying Time in Hours
0 2 4 6 8
SFO + 200ppm TBHQ 3.32 55.15 98.61 114.22 134.1
SFO + 200ppm Current Invention’s Formulation (Formulation A) 3.32 31.64 49.82 58.54 72.33
SFO + 200ppm Formulation B 3.32 49.68 58.54 78.39 92.13
SFO + 200ppm Formulation C 3.32 36.38 52.76 67.40 83.13
SFO + 200ppm Formulation D 3.32 47.03 64.23 79.37 97.17

The statement is more justified from the results obtained from the oil containing Formulations B, C and D in both set of oils Palmolein and sunflower. The efficacy of ascorbic acid in controlling the degradation products can be observed from the results of Formulation B (without ascorbic acid) having a p-anisidine value of 67.81 and Formulation D having 68.49 after 10:00 hrs of frying in Palmolein oil. In sunflower at the same time, after 8:0hrs of frying the p-anisidine values were 92.13 and 97.17 respectively for Formulation B and Formulation D containing oils. It can be noted that the citric acid included formulation gave remarkably very little role in adding stability but was better compared to mixed tocopherol added Formulation C. Comparing the citric acid formulation and ascorbic acid formulation it is the ascorbic acid that gave better results. Together ascorbic acid and mixed tocopherol along with rosemary extracts significantly controlled the secondary oxidation products during frying.
Further to this it can be stated that the degradation product of the current invention’s formulation breaks down to safe phenolic acids which in turn play a significant role in adding frying stability to the vegetable oil.

TOTOX Value
TOTOX Value indicates the overall oxidation of oil, which is calculated using the formula Anisidine Value + (2 x Peroxide Value). Better quality of oil has less Totox value. Increase in peroxide value and p-anisidine value gradually increases the Totox value of the oil samples. As there was steady increase in values after the 4:00th hrs of frying, this consequently attributed for the increase in Totox value On 10:00hrs of continuous frying current invention’s formulation added palm olein oil reached only 55.36 but TBHQ added oil attained 79.48, which almost, corresponds to an increase of 50% more degradation. The pattern was almost similar in sunflower oil samples also. Here the Totox value crossed 100 in the 4:0th cycle of frying in the TBHQ added oil, whereas the sunflower oil with current invention’s formulation was still at a value of 52.46, which is remarkably very safe in frying. Among the Formulations studied Totox value was highest in Formulation D in both set of oils but was much lower values than TBHQ added oil.

Table:9 Totox value during frying in RBD Palm olein oil
TOTOX VALUE

Sample Frying Time in Hours
0 2 4 6 8 10
PO + 200ppm TBHQ 5.08 46.27 69.04 76.89 75.82 79.48
PO + 200ppm Current Invention’s Formulation (Formulation A) 5.08 20.86 33.43 41.33 51.82 55.36
PO + 200ppm Formulation B 5.08 30.61 46.48 59.47 64.5 73.57
PO + 200ppm Formulation C 5.08 24.49 40.13 46.40 55.43 59.97
PO + 200ppm Formulation D 5.08 29.12 63.56 69.60 68.91 74.05

Table:10 Totox value during frying in Sunflower oil
TOTOX VALUE

Sample Frying Time in Hours
0 2 4 6 8
SFO + 200ppm TBHQ 3.74 58.93 104.93 122.42 140.36
SFO + 200ppm Current Invention’s Formulation (Formulation A) 3.74 34.16 52.46 63.08 77.11
SFO + 200ppm Formulation B 3.74 53.14 64.28 85.65 99.71
SFO + 200ppm Formulation C 3.74 39.16 56.26 73.02 88.73
SFO + 200ppm Formulation D 3.74 50.25 69.29 86.29 104.25

Oxidative Stability Study by measuring the Oil Stability Index (OSI)
The Rancimat method is considered as an accelerated determination of oxidation by conductimetric method evaluating the stability of vegetable oil by measuring the induction time. To determine the oil stability in the oils that are highly stable under normal conditions, the oxidation process is accelerated by introducing the oil sample to higher temperature in the presence of an excess amount of air or oxygen. This easily makes the oil rancid and hence the stability can be studied. Palm olein oil being saturated oil is stable at normal temperature and hence the Rancimat study was conducted at 1200C. Sunflower oil which is unsaturated oil is more prone to oxidation and hence the study was done at 1000C, in order to obtain a sufficient induction time to do a comparison.
The oxidative degradation of the fried oil was analyzed using Rancimat instrument –Metrohm 743, at an air flow rate of 20.0 liter per hour.
The effect of the current invention’s formulation, antioxidant in providing thermal stability can be further concluded from the set of studies. Here fresh RBD palm oelin oil with 200ppm TBHQ on initial blending (before frying) and palm olein oil with 200ppm current invention’s formulation on initial blending (before frying) were analyzed for obtaining its oxidative stability. Later, when frying was carried, the oil samples after frying (2 hours interval)were kept for measuring the oxidative stability. Here it can be seen that fresh oil had induction time of about 15.17 hrs, were as the synthetic antioxidant added palm olein oil reached to an induction time of about 28.58 hrs and current invention’s formulation added palm olein oil could reach an induction time of about 16.41hrs in Rancimat when the oils were analyzed before frying. Here we can notice that TBHQ is actively contributing for its oxidative stability. But the pattern was entirely changed when the oils used for frying were analyzed for its stability. The 2:00hr fried oil with TBHQ reached only to a time period of 9:00 hrs whereas the same oil with current invention’s formulation after 2:00 hrs of frying could reach to an induction time of 13.16 hrs. The induction time for the samples with 200ppm TBHQ during the the 4:00th hr, 6:00th hr and 8:00th hours after frying are 3.33, 1.99 and 1.43 hrs respectively. The fried oil with current invention’s formulation after the 4:00th, 6:00th and 8:00th hours of frying reproduced a data of 12.12, 11.88 and 11.17 hours as the induction time for being rancid. From this data it is very well clear that on frying TBHQ (at 200ppm the maximum permitted limit) do not add its contribution in improving the stability of oil imparting more oxidation and rancidity. The greater the induction time the greater is the stability of the oil. Even though the control palm olein oil with current invention’s formulation before frying did not show a better induction time when compared to TBHQ, the same could impart stability during deep fat frying. The data also thoroughly emphasize that TBHQ is highly unstable at higher temperature but current invention’s formulation is stable during the entire frying process.
The same pattern was followed with sunflower oil samples also were the oil with TBHQ before frying showed significant induction time but on frying the oil showed poor thermal stability. As mentioned before the sunflower oil being more easily oxidized the study was conducted at 1000C in the Rancimat. The induction time of TBHQ added Sunflower before frying was 39.61 and that of current invention’s formulation added sunflower oil was 14.18.
The oil after frying when kept for Rancimat produced the data which agree again to the conclusion that current invention’s formulation could significantly provide a role in thermal stability during frying.
When having a close focus on the oils with Formulations A, B,C and D, the role of each ingredient in enhancing the frying stability can be observed from the Rancimat results. On addition of antioxidant formulations (A,B,C) the oil before frying had an induction time around 16:0 hrs in Palmolein oil and around 14:00 hrs in sunflower oil, which was almost close with to their respective fresh oil. This gradually reduced after frying but the values were better than that observed for TBHQ. The oil samples after 8:00 hrs of frying with oil containing Formulation B,C and D had induction time of around 10:00 hrs in Palmolein oil, which was almost closer to the results of current invention’s formulation (Formulation A) which was 11:17 hrs. At the same time the 8:00 hrs fried oil containing TBHQ gave only 1.43 hrs indicating its poor stability and more oil degradation. In case of sunflower oil, 8:00 hrs fried oil containing formulations B, C and D attained around 7:00 hrs among which the formulation with mixed tocopherol proving higher induction time compared to the others.

Table 11: Rancimat analysis data of Palm olein oil samples (*PO-Palm olein oil)
SAMPLE DESCRIPTION INDUCTION TIME (Hrs)
Fresh Palm olein oil (PO) 15.17
PO + 200ppm TBHQ (before frying) 28.58
PO + 200ppm TBHQ (after 2 hrs frying @180 °C) 9.14
PO + 200ppm TBHQ (after 4 hrs frying @180 °C) 3.33
PO + 200ppm TBHQ (after 6 hrs frying @180 °C) 1.99
PO + 200ppm TBHQ (after 8 hrs frying @180 °C) 1.43
PO + 200ppm current invention’s Formulation A
(before frying) 16.41
PO + 200ppm current invention’s Formulation A
(after 2 hrs frying @180 °C) 13.16
PO + 200ppm current invention’s Formulation A
(after 4 hrs frying @180 °C) 12.12
PO + 200ppm current invention’s Formulation A
(after 6 hrs frying @180 °C) 11.88
PO + 200ppm current invention’s Formulation A
(after 8 hrs frying @180 °C) 11.17
PO + 200ppm Formulation B (before frying) 16.35
PO + 200ppm Formulation B (after 2 hrs frying @180 °C) 12.42
PO + 200ppm Formulation B (after 4 hrs frying @180 °C) 11.70
PO + 200ppm Formulation B (after 6 hrs frying @180 °C) 11.09
PO + 200ppm Formulation B (after 8 hrs frying @180 °C) 10.43
PO + 200ppm Formulation C (before frying) 16.22
PO + 200ppm Formulation C (after 2 hrs frying @180 °C) 12.09
PO + 200ppm Formulation C (after 4 hrs frying @180 °C) 11.48
PO + 200ppm Formulation C (after 6 hrs frying @180 °C) 10.87
PO + 200ppm Formulation C (after 8 hrs frying @180 °C) 10.18
PO + 200ppm Formulation D (before frying) 16.28
PO + 200ppm Formulation D (after 2 hrs frying @180 °C) 12.60
PO + 200ppm Formulation D (after 4 hrs frying @180 °C) 11.72
PO + 200ppm Formulation D (after 6 hrs frying @180 °C) 11.11
PO + 200ppm Formulation D (after 8 hrs frying @180 °C) 10.52

Table 12: Rancimat analysis data of Sunflower oil samples (*SFO- Sunflower oil)
SAMPLE DESCRIPTION INDUCTION TIME (Hrs)
Fresh Sunflower oil (SFO) 11.77
SFO + 200ppm TBHQ (before frying) 39.61
SFO + 200ppm TBHQ (after 2 hrs frying @180 °C) 8.52
SFO + 200ppm TBHQ (after 4 hrs frying @180 °C) 7.8
SFO + 200ppm TBHQ (after 6 hrs frying @180 °C) 7.21
SFO + 200ppm TBHQ (after 8 hrs frying @180 °C) 7.19
SFO + 200ppm current invention’s Formulation A
(before frying) 14.18
SFO + 200ppm current invention’s Formulation A
(after 2 hrs frying @180 °C) 9.93
SFO + 200ppm current invention’s Formulation A
(after 4 hrs frying @180 °C) 9.22
SFO + 200ppm current invention’s Formulation A
(after 6 hrs frying @180 °C) 9.1
SFO + 200ppm current invention’s Formulation A
(after 8 hrs frying @180 °C) 9.02
SFO + 200ppm Formulation B (before frying) 13.92
SFO + 200ppm Formulation B (after 2 hrs frying @180 °C) 8.98
SFO + 200ppm Formulation B (after 4 hrs frying @180 °C) 8.65
SFO + 200ppm Formulation B (after 6 hrs frying @180 °C) 8.12
SFO + 200ppm Formulation B (after 8 hrs frying @180 °C) 7.92
SFO + 200ppm Formulation C (before frying) 14.09
SFO + 200ppm Formulation C (after 2 hrs frying @180 °C) 8.71
SFO + 200ppm Formulation C (after 4 hrs frying @180 °C) 8.34
SFO + 200ppm Formulation C (after 6 hrs frying @180 °C) 7.99
SFO + 200ppm Formulation C (after 8 hrs frying @180 °C) 7.71
SFO + 200ppm Formulation D (before frying) 13.88
SFO + 200ppm Formulation D (after 2 hrs frying @180 °C) 9.08
SFO + 200ppm Formulation D (after 4 hrs frying @180 °C) 8.59
SFO + 200ppm Formulation D (after 6 hrs frying @180 °C) 8.21
SFO + 200ppm Formulation D (after 8 hrs frying @180 °C) 7.88

Conclusion:
Thermal degradation of oils at frying temperature results in a number of chemical reactions which includes hydrolysis, oxidation, thermal decomposition and polymerization. Prolonged heating also reduces organoleptic and nutritive quality of oils and the shelf life of food fried in it. Hence, antioxidant addition is necessary in vegetable oils to extent oil stability. Addition of synthetic antioxidants like TBHQ which is common in vegetable oils only attributes to its shelf life but do not provide stability during deep frying. The synthetic antioxidants also possesses great health concern in people, this can be easily overcome by using plant based alternatives.

The natural antioxidant for vegetable oil is able to provide better thermal stability when compared with the common synthetic antioxidants. These stabilizers for frying are a composite of natural active ingredients in the form of plant extracts, which offers sustainable, safer and healthier oil preservation. The formulations could control the major oil quality parameters like Total Polar Compounds (TPC), Free Fatty Acid (FFA), Peroxide value (PV), Totox Value and para-anisidine value. The antioxidant formulations greatest advantage is that it needs to be added only once as it is stable at 1800c. Hence repeated addition like synthetics after a period of time is not required. The natural antioxidant is easily soluble in oil and mixes well with normal stirring and hence there needs no additional processing steps. Being easily miscible in oil, it does not settle down unlike the synthetic ones. The stabilizer works well in RBD palm olein, corn, canola, rice bran, mustard, gingelly, sunflower, ground nut, cotton seed and soya bean oil.

Here current invention’s formulation provided better frying stability making the oil at a safer level of consumption. Besides it advantage as antioxidant the formulation being a combination of natural extracts, provides nutraceutical benefits. Hence, the product can be considered as a sustainable green label alternative for synthetic antioxidant at the same concentration. Furthermore to add, better oil in frying with increased antioxidant status, enhances the antioxidant status of food products fried and hereby the shelf life of the product is also observed more. That is the products when fried in current invention’s formulation will therefore get rancid slowly than the one fried with synthetic antioxidant. In conclusion this green label alternative, antioxidant formulation current invention’s formulation is capable of delaying the formation of total polar content, primary oxidation product like peroxides and secondary oxidation products answering the p-Anisidine value. It gave better frying stability when compared with the synthetic antioxidant TBHQ, when the oils were heated at 180°C.

In another embodiment, the formulation is analyzed for its efficacy as an antioxidant by preparing different concentration, according to an embodiment of the present technical disclosure.

In another implementation, thermal stability of the plant-based antioxidant formulation is analyzed by frying food product at predetermined temperature for predefined time, according to an embodiment of the present technical disclosure. The thermal stability study of the vegetable oil is done by comparing the quality parameters of the vegetable oil used for frying as well as the products fried in the vegetable oil. The comparison is performed between the vegetable oil with predetermined concentration of the plant-based antioxidant formulation prepared according to present technical disclosure and oil with addition of the conventional synthetic antioxidant of predetermined concentration. Vegetable oil without the addition of any antioxidant is used as a control. In another embodiment, the study is done in frying chamber with temperature controller and samples are withdrawn at an interval of 2:00 hours of frying. The oil used for frying and product fried are also analyzed for quality parameters. In another embodiment, the vegetable oils are analyzed for the Total Polar Compounds (TPC), Free Fatty Acid Content (FFA), Peroxide value (PV), Para-anisidine value (P-AV), Totox value (Tv) and the fried product is analyzed for its oil content and peroxide value.

In one embodiment the frying process is carried out by frying suitable product in an electric fryer. The frying process is continued till the Total Polar Compounds (TPC) reached at standard value (as per Food Safety and Standards Authority of India (FSSAI)). The quality parameters of frying oil namely TPC, Free Fatty Acid, Peroxide value, Totox Value and para-anisidine value are analyzed at periodic intervals to analyze its degradation. In yet another embodiment, oxidative stability of the fried oil is also analyzed using standard Rancimat instrument for further cross checking its extent of degradation.

In another embodiment the plant-based formulation which is used as a stabilizer works well in various types of vegetable oils such palm olein oil, corn oil, cotton seed oil and soya bean oil and the like.

ADVANTAGES
• The plant-based formulation which acts as a thermal stabilizer for vegetable oil is effectively used as an antioxidant at minimum concentration of 200 ppm. The formulation gives better frying stability to oil when compared with same concentration of the synthetic antioxidant such as but not limited to TBHQ (the comparison is done at the maximum permitted level of antioxidant allowed as per regulatory standards of international food standards body).
• The formulation prepared as per the present disclosure is suitable for a wide range of vegetable oils like RBD Palm olein, Soy bean, Cotton seed, Sunflower, Corn, Ground Nut, Canola, Rice Bran, Mustard, Gingelly, Mixed edible Oils, and the like.
• The formulation prepared as per the present disclosure effectively controls TPC, FFA, PV and P-AV of oil.
• The formulation prepared as per the present disclosure is stable at high temperature, providing better stability during frying than TBHQ, the synthetic antioxidant.
• The formulation prepared as per the present disclosure is easily soluble in oil.
• The formulation prepared as per the present disclosure does not degrade into unsafe polymerized hydrocarbons on heating.
• The formulation prepared as per the present disclosure requires only single addition that can stabilize the frying process, whereas any synthetic antioxidant requires additional dosage on frying after the initial hours
• The formulation prepared as per the present disclosure reduces oil splattering and smoking of oil. It was observed that smoking in current inventions’s formulation added oil was not common during frying but TBHQ added oil started smoking when TPC of oil reached above 20.0. The data can be supported by stating that as the seconadry oxidation products are found less, there is only a minimum polymerisation happening in oil added with the current invention’s formulation which can cause reduced smoke on frying.
• The formulation prepared as per the present disclosure delays oil color change on an extra 1to 2 days in frying.
• The formulation prepared as per the present disclosure provides better sensory attributes to fried products in terms of texture, color, and mouthfeel.
• Shelf life of fried product prepared in the vegetable oil with the plant -based formulation of the present disclosure increased 3 times when compared with the control.
• The formulation prepared as per the present disclosure reduces the risk of carcinogens during frying as they do not degrade into unsafe products.
• The formulation prepared as per the present disclosure is easily miscible in oil. No additional machinery or process cost involved as a result of the addition of formulation present in the present disclosure. Hence no capital investment required during any stage of addition into oil whether at refineries or at frying industries.
It should be noted that the description merely illustrates the principles of the present invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present invention. Furthermore, all examples recited herein are principally intended expressly to be only for explanatory purposes to help the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass equivalents thereof.
,CLAIMS:WE CLAIM:

1. A plant-based formulation for enhancing frying stability of a vegetable oil; said formulation comprises:
g) rosemary extracts in an amount of 40 to 60% w/w;
h) rosemary oleoresin in an amount of 5 to 10% w/w;
i) lecithin in an amount of 2 to 10% w/w;
j) ascorbic acid an amount of 1 to 5% w/w;
k) mixed Tocopherol an amount of 8 to 15% w/w; and
l) glycerides an amount of 45 to 70% w/w.

2. The formulation as claimed in claim 1, wherein rosemary extracts comprises 50% carnosic acid

3. The formulation as claimed in claim 1, wherein rosemary oleoresin comprises 8% carnosic acid.

4. The formulation as claimed in claim 1, wherein the formulation comprises 2 to 6 % of 50% carnosic acid and 12 to 18% of 8% carnosic acid.

5. The formulation as claimed in claim 1, wherein the formulation comprises 4 to 5 % of 50% carnosic acid and 15 to 16% of 8% carnosic acid.

6. The formulation as claimed in claim 1, wherein the amount of lecithin in an amount of 6 to 7% w/w;

7. The formulation as claimed in claim 1, wherein the amount of ascorbic acid an amount of 3 to 4% w/w.

8. The formulation as claimed in claim 1, wherein the amount of mixed Tocopherol is 10 to 11%w/w.

9. The formulation as claimed in claim 1, wherein the glycerides comprise mono and di glycerides in an amount of 55 to 65% w/w.

10. A process for preparing a plant-based formulation, wherein said process comprises the following steps:

i. taking rosemary oleoresin with 8% carnosic acid in a vessel and adding rosemary extract with 50.0% carnosic acid to said vessel followed by mixing thoroughly with an agitator rod to obtain a mixture;
ii. adding ascorbic acid and a portion of mono and diglycerides to said mixture followed by mixing to obtain a blend;
iii. transferring said blend to a ball mill to grind and obtain a second mixture having particle size in the range of 200 to 250 micro meter;
iv. adding lecithin to said second mixture followed by blended for 30 to 90 minutes to obtain a mass;
v. adding mixed tocopherol and a portion of mono and diglycerides followed by mixing to obtain a pre-formulation; and
vi. passing said formulation through a homogenizer to obtain the formulation.