Title of Invention

AN IMPROVED PROCESS FOR THE COATING AND FLAVOURING OF SNACK FOODS

Abstract

An improved process for the coating and flavouring of snack foods This invention relates to an improved process for the coating and flavouring of snack food.This ready-to-eat product can be prepared from expanded or puffed or extruded grain based products such as puffed rice, puffed pulses and popcorn. The process is also suitable for non-expanded products like dry-roasted cashew nut and peanut/groundnut. The specific advantage of the product lies in the flexibility of the taste, uniform coating/flavouring, attractive crispness of the finished product. Loss of coating/flavouring materials in form of salt/spice etc is negligible during handling and transportation that is very common in conventionally prepared products. The low-fat content in the finished product can be an added advantage for the developed products such that they can be used as a health food.

Full Text

This invention relates to an improved process for the coating and flavouring of snack foods. Cereals, pulses and their combinations constitute an important part of human diet in many parts of the world because of easy availability, low-cost, long shelf-life and nutritional balance. Several traditional foods as well as technologically improved products, either as a ready-to-eat or ready-to-prepare form, made from such combinations, are popular. A significant portion of them are made by fermentation or puffing or roasting, or by deep fat-frying the grain or dough pieces, and finally, they are used as a snack or as a breakfast food item. Usually, the manufacture of RTE snack involves frying and/or addition of fat to obtain convenience foods especially ready-to-eat snacks. Breakfast cereal is one of the many convenience foods and is generally marketed in the ready-to-eat (RTE) form. Puffed or expanded rice products and extruded cereal products, though ready-to-eat products, are usually bland to taste. This occurs due to heat treatment that takes away the inherent flavours along with escaping steam. Puffed or expanded rice is one of the widely used traditional products throughout India possibly due to its attractive crisp texture, low cost and convenience in use. Due to bland taste, the consumers often add salt and seasonings or mix with other condiments prior to consumption. Often several colouring matters such as turmeric is used to provide an attractive appearance instead of having an pale white colour of the expanded puffed product. At the same time, it is extremely difficult to prepare a product with uniform coloured and flavoured product from such expanded products. The main reason being the large surface-to-volume ratio or simply the low density of the product onto which flavouring/coating material is to be dispensed. The other drawback lies in the loss of salt and flavouring/coating materials during transportation, handling and storage due to physical segregation. The net result is the accumulation of such materials at the bottom of the packet, and therefore, the consumption of the bottom portion of the product gives an adverse effect to the consumer. There is a need to develop a cost effective process to produce an attractive uniformly coated crisp RTE cereal snack food. Further, if the developed product possesses highly crisp texture with an attractive mouth feel in combination with low-fat content, it can be considered as a health food. A few processes available for the production of snack products from cereals in different countries are described. It may be mentioned here that snacks are to ready-to-prepare or ready-to-eat forms of which the latter is more desirable considering the convenience of use. Reference may be made to the US Patent 6365203B2 (2002) on continuous coating of chewing gum materials wherein small cores or pieces of gum materials are introduced into inclined rotating drums in which heated air is circulated, and a coating solution is applied to obtain the coated product. The draw back of the process lies in the fact that raw material for coating as well as the finished product is not the same one used in the present work which is from expanded extrudates and puffed rice. Reference may be made to the US Patent 0031573 A1 (2002) on sugar coated products and process for the same wherein the coating material used is fruit flavoured sugar alcohol. The draw back of the process lies in the fact that the process of coating is not the same as the present attempt has been made. Further, the present invention does not use any sugar alcohol as the coating material. Reference may be made to the French Patent FR 2811913 A1 (2002) on the process for encapsulation of fine solid particles in the form of microcapsules, wherein a process was described for microencapsulation of fine solid particles including food ingredients. The mixture was sprayed through jets and thus the carrier liquid vaporizes, and the coating agent surrounds the particles to form microcapsules. The draw back of the process lies in the fact that coating process was done after mixing the coating agent with a carrier liquid at a pressure lower than its critical pressure which is difficult to maintain in addition to elevation of processing cost. In the present invention, coating was conducted at ambient pressure. Reference may be made to the European Patent EP 1170060 A1 (2002) on process for electrostatic spraying of fluids and dry materials onto food products via spray jets, wherein a process for uniform application of same emulsions and solid ingredients, e.g., binding agents, flavourings or other seasonings by electrostatic spraying was described. The drawbacks of the process lie in the fact that the process is especially applicable to frozen vegetables. Moreover, quantities of same emulsion and dry ingredients applied are controlled by a method using computer linked weighing machine and flow sensors which is rather complicated and cost rendering process. Further, electrostatic coating process requires the application and maintenance of high voltage in the order of 10 or 20 kilo volts which makes the whole process complicated and cost intensive. Reference may be made to US Patent 6207207 B1 (2001) wherein claims have been made for the development of a coated confectionery with a crispy texture having starch as the base. The integrity of the coating is maintained even after storage for extended periods. The drawback of the process is the non-uniform coating of the starch based centre. Moreover, a continuous outer sugar shell coating was done surrounding the starch based centre, which is different from the present invention. Reference may be made to US Patent US 5 750 166 (1998) (Composition and method for flavoring popcorn product by S.R. Schellhaass) wherein claims have been made for a method of coating unpopped popcorn kernels in order to enhance their flavour. One application of the method involves adding an aqueous-based adhesive to unpopped popcorn kernels followed by addition of a dry flavouring component. Excess moisture can then be dried from kernels, after which a flavouring facilitator is applied in order to enhance the flavour of the product. A coated, unpopped popcorn product, which can be popped in a microwave oven with no added oil or fat, is also described. The draw back of the process lies in the fact that coating was done on the unpopped material after which a flavouring facilitator is applied which is not like the present method follows. Further, unpopped popcorn has a high density which is different from materials used here which typically possess a low density. Reference may be made to US Patent US 5 702 745 (1997) (Process for making shelf-stable, ready-to-eat rice) wherein claims have been made for a method of preparing shelf-stable, ready-to-eat rice products. The method involves coating pregelatinized rice grains with an emulsifier. A food acid and glucono-delta-lactone are then added to the coated rice to lower the pH to 4.6. The rice is then thermally treated at a temperature and for a time sufficient for sterilization. The resulting products have the same or superior texture, appearance and flavour when compared to other commercially produced, shelf-stable, ready-to-eat rice products. The limitation of the process lies in the fact to lower and maintain the coated rice pH to 4.6 which is again thermally treated for sufficient sterilization. A low pH also results in an undesirable sour taste. Reference may be made to US Patent US 5 514 399 (1996) (Method of applying particulates to baked goods and snacks) wherein claims have been made for uniform coating of the top and bottom of bakery and snack products with a particulate composition (e.g. seasoning or spice). The draw back of the process lies in the fact that the method involves applying the composition as a curtain or sheet via a series of adjustable nozzle openings which is entirely different method from the present one. Moreover, the raw material is not the expanded extrudates or puffed rice used in the present investigation. Reference may be made to electrostatic coating technology for savory snacks by G. Clark (Electrostatic coating technology for savoury snack. Food Technology Europe, 2(3), pages 90-96, 1995) wherein claims have been made for the use of electrostatic coating technology to achieve greater homogeneity and to reduce costs during the application of flavourings. Aspects considered include the extent of flavouring wastage, principles of electrostatic flavour application, methods of application, benefits of electrically coating products, systems to monitor mass flow variation and automatic modulation of flavouring additions, development of flavourings for use with electrostatic coating technology and electrostatic coating methods (Tribo charge, corona discharge and induction). The limitation of the literature is lying in the fact that the present process is not done by electrostatic coating that is not only a complicated process but also costly. Reference may be made to US Patent 49272645 and US313048 (1990) wherein claims have been made for the development of candy coated snack foods such as popcorn. The process involves popping corn kernels in a microwave oven and melting a candy bar of specified formulation and dimension over the popcorn. The drawback of the process is that the raw material is a microwaved popcorn and coated with a melted candy bar which is entirely different way of making the product. In addition, product flavoured in such methods produces a non-uniform coating and the flavoured particles tend to lose during transportation and handling. Reference may be made to US Patent US 4769247 (1988) (Method for adhering spices on the surface of pasta by Rothenberg et al) wherein claims have been made for a continuous process of preparing a non-segregating, free-flowing dried instant pasta and sauce dish. The processes used involve preheating, conveying the pre-heated pasta to a rotating coating reel, applying a 1st layer of melted fat to the pasta, contacting the fat-coated pasta with dry spice ingredients, applying 2 further layers of fat, adding vegetable inlays and cooling for packaging. The limitation of the process lies in the fact that way of coating is entirely different from the present technique and the material under coating is not a low-density porous material like expanded extrudates or puffed rice. Reference may be made to US Patent US 4 755 390 (1988) (Process for the production of a flavored cereal product by Calandro et al.) wherein claims have been made for flavouring-coated cereal capable of releasing the coating on immersion in milk, produced by wetting the surface of a cereal product with a sugar solution, sprinkling a particulate flavouring composition (e.g. ground hard candy) onto the cereal product while it is still wet with the sugar solution, and then drying the cereal product. The draw back of the process lies in the fact that the method of coating is entirely different from the present one. Reference may be made to US Patent US 4 743 456 (1988) (Apparatus and method for applying a uniform coating to food by Spadafora et al.) wherein claims have been made for crackers by evenly coating with a viscous, spice-containing flavouring oil using the described spraying equipment. The draw back of the process lies in the fact that the equipment used in the present investigations are entirely different, and also the process of making is not the same one like used in the present work. Reference may be made to US Patent US 4 338 339 (1982) (Cocrystallization of dextrose and sucrose on cereal products) wherein claims have been made for dextrose and sucrose to be co-crystallized onto the surface of breakfast cereal products such as corn flakes, puffed wheat or puffed rice, by applying to the product surface a powdered crystalline material comprising any of sucrose, dextrose or their mixtures and coating the surface with a layer of a concentrated aqueous solution of dextrose and sucrose. The coated cereal product is then dried at a temperature below the browning temperature of the product. The resulting coated cereal product has a desirable frosted appearance. The main draw back of the process lies in the fact that the way of coating is not the same as employed in the present investigation. Moreover, it is a thick sugar coated product and has a frosted appearance while the present product is a salt-spice flavoured one. Reference may be made to the German Federal Republic Patent 2705 718 (1978) (Method for preparation of snacks from pre-roasted nuts which are sprinkled with a spice, coated with dry flour and the coated material is baked in an oil bath) wherein claims have been made for a type of confectionery of low calorie and high vitamin content. It is made from pre-roasted nuts and kernels, such as hazel-nuts, almonds, pine kernels, which are sprayed with a seasoning suspension of water, salt, condiments and flavourings, and then coated with a dry flour, possibly flavoured, and the coating is finally baked at 140-170°C. The draw back of the process lies in the fact that the method of coating is of a different kind where finally the coated product is baked in oil bath. Moreover, the raw material is different from the present one. Reference may be made to the British Patent 1 327 528 (1973) (Flavored rice product) wherein claims have been made for coated rice with shellac containing a flavouring agent such as a carbonyl compound. The film coating acts to prevent removal of the flavouring agent during washing prior to cooking. The draw back of the process lies in the fact that shellac is used as a coating media which is not a food material. Moreover, this is not a ready-to-eat food product. The main objective of the present invention is to provide an improved process for the coating and flavouring of snack foods. Another object is to provide an improved process for producing a low-fat snack foods. Another objective is to provide an improved process for low-density food products such as from expanded extruded products, puffed rice and popcorn, etc. Yet another object is to prepare uniformly coated puffed snack products. Yet another object is to prepare uniformly coated dry-roasted products like peanuts, cashew nuts and a mixture thereof. Yet another object is to provide a cost-effective process for the preparation of ready-to-eat flavoured puffed snack foods. Yet another object is to have an attractive crisp texture in the product. Yet another object is to have product that would not lose flavouring/coating material during handling and transportation. Accordingly, an improved process for the coating and flavouring of snack foods comprising: a) cleaning, grading and drying the material at 40 to 120°C for a period ranging 10 to 60 minutes b) adding flavor and binding ingredients in the form of maltodextrins to the dried material as obtained step a) and sprinkling 0-5 wt% of flavoring agent; c) polishing the surfaces of the mixture as obtained in step b) with 0-5 wt% oily materials; d) polishing the surfaces of the mixture as obtained in step b) with antioxidants to obtain coated and flavored ready to eat snack food. In an embodiment the snack food used is selected from group of extruded and/or puffed cereals, and mixture of cereals and pulses. The process is also suitable for dry pulses and roasted cereals and pulses, nuts like cashew nuts, peanuts or groundnut, and a mixture thereof. In an embodiment 0-50 wt% maltodextrin dispersion is used as a flavour binder. In yet an another embodiment 0-5 wt% of flavoring agent addition comprises of chili powder, turmeric powder, black pepper powder, oleoresin, sugar powder, food colour, garlic powder, cinnamon powder, cardamom powder, vanilla or mixture thereof. In yet an another embodiment the oils for polishing is selected from a group of edible oil or hydrogenated fat with permitted antioxidants. In yet an another embodiment uniformly coated or flavoured ready-to-eat puffed snack food having a savoury taste that does not come out during handling and transportation that frequently happens with conventionally flavoured product using oil as a binding agent for powdered flavours. In yet an another embodiment the antioxidant used is 0-0.02 % w/w of fats/ oils and the said antioxidant is selected from a group of butylated hydroxy anisole, tertiary butyl hydroquinone or mixture thereof. In yet an another embodiment the fat content of the product is in the range of 1 to 5% w/w. In yet an another embodiment the coated and flavored snack food is used as ready-to-eat snack, breakfast cereal and as a health food. Novelty Novelty and inventive steps of this invention lie in the fact that an improved process of coating method is developed to obtain smooth and uniform coated ready-to-eat puffed snack foods of attractive crisp texture by employing the principle of special technique of coating technology particularly for low-density expanded or puffed or extruded cereal products. The summary of the steps of the process of the present invention is: a) Cleaning, grading of the expanded or puffed or extruded cereal product, b) toasting the product at 40 to 120°C for 10 to 60 min to obtain a crisp product and to bring down moisture content to a safe moisture of range 1 to 6 wt%, and c) employing a special technique of coating technology with other desired ingredients to obtain uniformly coated or flavoured ready-to-eat puffed snack foods. The product is then packed in a suitable moisture-proof packaging material. The process is further illustrated by the examples given below which should not however be construed to limit the scope of the invention. Example 1 Process for salt-spicy coated or flavoured readv-to-eat puffed snack food from expanded rice Two kg of cleaned expanded rice with a bulk density of 112 kg/m3 was dried in a tray drier at 70°C for 30 min to attain a moisture content of about 5%. The dried rice product, while in motion, was coated with a thin slurry of maltodextrin to adhere the sprinkled salt and spice powders in a rotary coating pan with hot air blowing facility to obtain salt-spice adhered snack. The product, while in motion, was then finally polished or glazed by warm (55-60°C) hydrogenated fat along with permitted antioxidant. The products were packed in moisture-proof polypropylene packets. The colour of the uncoated product was enamel white whereas the finished product possesses a uniform bright yellowish white colour. The bulk density of the finished product is between 100 to 120 kg/m3. The proximate composition for spiced product is moisture 5.6%, protein 4.5% and fat 2.6%. The loss of salt-spice mix during the simulated vibration-cum-mixing study were between 0.31 and 0.65% (based on the total net weight of product) for commercially procured samples that had been manufactured following the conventional coating/flavouring processes, while it was less than 0.04% for the products developed in this investigation. Puffed Bengal gram dhal, roasted groundnut and sliced copra (dry coconut kernel) pieces, coated/ flavored separately in a similar fashion, were mixed with the main bulk of puffed rice to get the finished salt-spicy mix. Example 2 Process for garlic flavoured readv-to-eat expanded rice and popcorn Two kg of cleaned expanded rice was toasted in a hot air toaster at 80°C for 2 minutes. The toasted expanded rice was then coated with thin slurry of maltodextrin to adhere salt-spice powder and garlic powder, as mentioned in example 1, in a rotary coating pan to obtain salt-spiced snack. The product is then finally polished with warm hydrogenated fat along with oleoresins and antioxidant followed by packaging in moisture-proof polyethylene packets. The colour of the uncoated product is a dull white whereas the finished product possessed a uniform attractive bright orange colour. In a similar manner, popcorn was also coated and flavoured with garlic powder along with other ingredients such as salt, spices and oleoresins as described earlier. The finished product has an attractive bright yellow colour. Example 3 Process for readv-to-eat puffed extruded snack food Two kg of highly expanded extruded corn curls, obtained by single-screw extrusion of a blend of corn grit (95%) and rice grit (5%), was toasted and then coated with maltodextrin dispersion in a rotary coating pan while blowing hot air, sprinkling with salt-spice mixtures, addition of fat followed by cooling and packaging (Figure 1). Texture of the extruded products (before and after coating) was determined using a Universal testing machine under compressive loading. The force-deformation curve of the finished product indicated that the product is crisp showing multiple major and minor fractures at a low load (Figure 2). (Figure Removed) Figure 1. Flow-chart for the production of coated/flavoured corn snacks (Figure Removed) Figure 2. Force-deformation curve for the developed coated/flavoured extruded corn snack The sensory assessment of the product was conducted according to QDA method where the panelists were instructed to rate the samples for overall quality. A 15 cm QDA scale, anchored at 1.25cm as low and 13.75cm as high was used to evaluate the extruded product. The very high overall quality score of 12.0 (Table 1) indicated the acceptance of the product. (Table Removed) Table 1 Sensory quality of extruded snacks Example 4 Process for dry roasted salt-spiced coated groundnut and cashew nuts Two kg of peanut or groundnut kernels with outer red skin was toasted in a hot air batch toaster at 120°C for 8 minutes. The toasted groundnut was then coated with a thin slurry of maltodextrin to adhere salt-spice powder, as mentioned in example 1, in a rotary coating pan to obtain salt-spiced groundnuts. The product is then finally polished with warm hydrogenated fat along with antioxidant followed by packaging in moisture-proof polyethylene packets. In a similar manner, 2 kg of cashew nuts were dry-toasted at 70°C for 4 minutes followed as coating with salt and spice powders as mentioned earlier. The colour of the uncoated cashews was dull in appearance while that of the finished product possessed a uniform attractive bright white colour. Example 5 Process for coated peanut/groundnut and puffed Bengal gram (chickpea)ed garlic flavoured readv-to-eat expanded rice and popcorn Two kg of cleaned expanded rice was warmed in a tray drier at 80°C for 2 minutes. These expanded rice was then coated with thin slurry of maltodextrin to adhere salt-spice powder and garlic powder, as mentioned in example 1, in a rotary coating pan to obtain salt-spiced snack. The product was then finally polished with warm hydrogenated fat along with oleoresins and antioxidant followed by packaging in moisture-proof polyethylene packets. The colour of the uncoated product is a dull white whereas the finished product possessed a uniform attractive bright orange colour. In a similar manner, popcorn was also coated and flavoured with garlic powder along with other ingredients such as salt, spices and oleoresins as described earlier. The finished product has an attractive bright yellow colour. Advantages of the invention The developed process of making RTE puffed snack food provides an attractive crisp texture, bright surface and has a good acceptability. The process of toasting/drying helps in developing attractive crispness to the products. The process of preparation involves technologically simple steps like drying and flavouring/coating and does not require any sophisticated and costly equipment like electrostatic coating etc. The product can be introduced as a snack food or RTE breakfast item; it is also suitable as a health food due to low fat contents. The raw materials for processing can be of different origin such as cereals and pulses. The process can be used for different products with low density such as puffed or expanded or extruded cereal products, puffed rice, popcorn etc. The process is also suitable for non-puffed products including dry roasted cereals and pulses, nuts like cashew nuts, peanuts or groundnut, and a mixture thereof. The present process provides uniformly coated/flavoured products that is highly desirable for the commercial success. The process gives a product from where the flavoured/coated material does not come out during handling and transportation. The claimed present process provides a method to coat/flavour expanded or puffed products that has a very high surface to mass ratio. We claim: 1. An improved process for the coating and flavouring of snack foods comprising e) cleaning, grading and characterized in that drying the snack food material as herein described at 40 to 120°C for a period ranging 10 to 60 minutes, f) adding flavour binder 0 to 50 wt% in the form of maltodextrins to the dried material as obtained step a) and sprinkling 0-5 wt% of flavoring agent as herein described, g) polishing the surfaces of the mixture as obtained in step b) with 0-5 wt% oily materials; h) polishing the surfaces of the mixture as obtained in step b) with antioxidants 0-0.02 % w/w of fats/oils to obtain coated and flavored ready to eat snack food. 2. A process as claimed in claim 1, wherein the snack food material used is selected from group of extruded and/or puffed cereals, mixture of cereals and pulses, dry pulses, roasted cereals and pulses, nuts like cashew nuts, peanuts or groundnut, and a mixture thereof. 3. A process as claimed in claims 1 to 2,wherein flavoring agent addition comprises of chili powder, turmeric powder, black pepper powder, oleoresin, sugar powder, food colour, garlic powder, cinnamon powder, cardamom powder, vanilla or mixture thereof. 4. A process as claimed in claims 1 to 3, wherein the oily material for polishing is selected from a group of edible oil or hydrogenated fat with permitted antioxidants. 5. A process as claimed in claims 1 to 4, wherein the antioxidant used is selected from a group of butylated hydroxy anisole, tertiary butyl hydroquinone or mixture thereof. 6. A process as claimed in claims 1 to 5, wherein the fat content of the product is in the range of 1 to 5% w/w. 7. An improved process for the coating and flavouring of snack foods substantially as herein described with reference to the examples accompanying this specification.

Documents:

482-DEL-2004-Abstract-(07-09-2009).pdf

482-del-2004-abstract.pdf

482-DEL-2004-Claims-(07-09-2009).pdf

482-del-2004-claims.pdf

482-DEL-2004-Correspondence-Others-(07-09-2009).pdf

482-del-2004-correspondence-others.pdf

482-del-2004-correspondence-po.pdf

482-DEL-2004-Description (Complete)-(07-09-2009).pdf

482-del-2004-description (complete).pdf

482-del-2004-form-1.pdf

482-del-2004-form-18.pdf

482-del-2004-form-2.pdf

482-DEL-2004-Form-3-(07-09-2009).pdf

482-del-2004-form-3.pdf

482-del-2004-form-5.pdf