CA1191380A

CA1191380A - Flowable dried aromatic plant product and process for making same

Info

Publication number: CA1191380A
Application number: CA000421985A
Authority: CA
Inventors: Richard Kellermann; Klaus Bezner; Hans Bohrmann; Florian Biller
Original assignee: Unilever Bestfoods North America
Current assignee: Unilever Bestfoods North America
Priority date: 1982-02-20
Filing date: 1983-02-18
Publication date: 1985-08-06
Also published as: IE53865B1; JPS58158130A; FI75479B; YU39283A; EP0087717B1; DK70983A; EP0087717B2; GB8304575D0; DE3361882D1; MY8600484A; FI830507L; NO830564L; IE830181L; DK160176C; ES519899A0; AR231489A1; FI75479C; PT76209A; FI830507A0; TR21351A

Abstract

ABSTRACT

Flowable, dried aromatic plant products containing herbs or aromatic vegetables, which are prepared by stabilizing them in the freshly harvested state (or, if frozen products are used, during or immediately upon thawing) and drying them under mild conditions in the presence of a suitable carrier. As carriers, salts (electrolytes), proteins and carbohydrates may be used alone or in combination. The stabilization step consists of either heating to 50° - 150°C or mixing with an electrolyte or both.

Description

Case 3279 . SUMMA~Y OF T~E INVENTION

The present invention relates to flowable~ dried aromatic plant product and a proc~ss for making same. In particular, the present invention relates ~o a product containing dried aromatic plant materials, such as herbs, which have superior flavor and appearance. Such a product may be advanta~eously employed in commercial dehydrated food mixtures; particularly in dehydrated soups, dehydrated sauces or dehydrated stew mixtures.

BACRGROUND ~F T~E lNV~hl ION

One of the factors which ha~ always determined the qual-ity of a food or a prepared dish, reflecting therefore of the abilities of the cook who prepared itr has been the kind and variety of seasonings employed. Apart from such common and readily available ingredients as salt, sugar and vine~ar, ~arious herbs and vegetables which have a distinctly aromatic fl~vor (referred to colleotively hereinafter a~ "aromatic plants~) have always played a major role by providing more subtl2 but di~-tinctive flavor notes to prepared foods. In addition, ~ome aro mati~ plants particularly when fresh, provide a prepared ood wit~ a.more attractive appearance~ Such aromatic plants, when they are available, are often employed primarily for decoration.

Unfortunately, most aromatic plant~ do not keep well~ and their flavor and appearance suffer noticeably during periods of 3L3~

storage. In additiony freshly harvested aromatic plants are sometimes available only in certain regions, and because of their various climatic requirements, they are generally only available on a seasonal basisO Because the desire for such materials continues thro~ghout the year, various methods have been employed in order to overcomP the poor keeping properties of these materials.

The various approaches which have been pursued can be classif.ied into three general groups:

l) Supplement the local supply of freshly harvested aromatic plants by such methods as providing facilities for growing such plants independent of climatic conditions or high-speed transportation of plant materials from great distances.

2) Extend the storage life of such materials through various "wet pres~rvation" techniques, including stacking~
salting~ pot~ing, candying and more recently, freezing.

31 Extend the storage life of such materials by con-verting them into dried products9 that is dried aromatic plants or essences.

- While the first two of these approaches have shown remarkably good results for many applications, aromatic plants in these forms generally contain at least their original water content. As such, such materials are not suitable for use in dehydrated food products, ~uch as the dehyrated soups and ~auces which make up a ~ubstantial part of commercially produced foods.

Notwiths~anding the enormous development of technology in general and of food technology in particular over the last several decades, the procedures employed in drying aromatic plants have remained basically unchanged. The quality of such dried aromatic plants is practically unchanged from what it was hundreds of years ago.

Various aromatic plantsl particularly certain species of plant origin like cloves~ nutmeg, saffron or pepper, are-commonly and almo~t exclusively used in dried orm. There are even some, such as bay leaf r which are actually improved by the traditional drying process. Others, such as savory, are ef-fected little if at all, particularly with regard to flavor properties.

Traditional methods of drying, however, are no~ably un-successful with such aromatic herbs as-~hives, dill~ basil, lovage and especially parsley. When dried according to commonly known methods such herbs loose nearly all of their flavor and color and are little more than aromatic ~hayn. In truth, their use in dehydrated foods and in home cooking is more because of habi'c than the ~lavor or color such herbs contribute in the dried state.

3~
Even the newly adopted techni~ue of 0freeze-drying", which is relatively complicated and costly, does not produce much of~an improvement.

In addition to the loss of their color, the appearance of most tradi~ionally dried aromatic plants suffers further because herbs dried in this manner unvariably show unsatis-factory mechanical properties. The impact of various shearing orces which are unavoidable during the manufacture, packaging and handling of dehydrated foods causes the brittle dried herbs to ~rumble, oten resulting in an unslightly p~wder.

Another approach which has proven to be unsatisfactory is the preparation of essences. Apart from their natural lack of eye appeal, e~perience has shown t~at such essences exhibi~
a flavor spectrum which is; as a rule, distinctly changed from the flavor of the original herbs, Objects of the Present Invention It is an object of the present invention to provide dried aromatic plant products which are superior to those of the prior art~

; It i~ a further o~ject of the present invention to provide dried aromatic plant product~ with improved me~hanical properties including increased resistance to shear forces.

It is a stil~ urther object of the present invention to provide dried aromatic piant products which exhibit improved fla~r.properties.

It is another object o~ the present invention to provide dried aromatic plant products which exhibit improved appearance propertiesO

It is still another object of ~he present inventton to provide dried aromatic plant products which exhibit greater storage stability.

The objects, features and advantages of the present invention will become more apparent in light of the following detailed description thereof.

According to the present invention, there is provided a process for the preparation o~ a flowable, dried aromatic plant product having an aromatic plant component and an edible, water-soluble carrier component, which process comprises the Qteps o~:

( a) treating an aromatic plant component comprised of one or more comminuted aroma~ic herbs or vegetables in at . least one stabilizing step selected from the group consisting of~
(1) mixing said aromatic plant component with an electrolyte selected from the group consis~:ing 3~3~

of alkaline and alkaline earth salts of organlc and inorganic acids, and ~2) quickly heatiny said arom~tic plant component to a temperat~re of from 50C to 150C and maintaining said temperature for a period of from 2 seconds to 1 hour, to form a stabilized ~omponent;
,, (b) adding to said stabiliæed component and uniformly mixing therewith a carrier component in a proportion which will yield from 10 ~o 90 percent by weight of the total dry matter of the final dried product, which carrier component c~mprises at least one edible, water-soluble compound select~d from the group consisting of:
(1) an electrolyte selected from the group consisting of alkaline and alkaline earth salts of organic and inorganic acids, all or any portion of which may have been previously added in s ep ~a~(l), : (2) proteins, and (3) hydrogenated and non-hydrogenated carbohydrates, to produce a stabilized plant/carrier mi~ture; and (c) drying the stabilized plant/carrier mixture for a suPfi-cient period of time to produce a flowable, dried aromatic plant product in such a manner that the temperature of the mixture is not permitted to exceed 70C~

~ 6 --Detailed Description of the Invention The advantages of the present invention are mo~t clearly demonstrated with aromatic plants which have previously been known for their poor properties when dried in the traditional manner. .In particular, these are such vegetables as leek, fennel, red and ~reen peppers, celery leafstalks and sweet marjoram as well as such herbs as thyme, chervilr ~ress, ~hives, dill, lovage, basil, tarragon and parsleyO

The central feature of the present Invention is the drying of aromatic herbs and vegetables in ~he presence of an edible, water-soluble carrier which may be any combina~ion of 1) an electrolyt2 chosen from the group consisting of alkaline and alkaline earth salts of orga~ic and inorganic acids, 2) proteinsy and 3) hydrogenated and non-hydrogenated carbohydrates~

Aromati~ herbs and vegetables prepared in this manner have better flavor and color ~roperties than herbs and vegetables prepared by the methods of the prior art.

In order for this drying procedure to be efective, however, the herbs and vegetables must first be subjected to a ~tabiliza-tion step.

l :L91~

If the carrier chosen for the drying step is an electro-lyte~ such a compound has the ability to reduce the avaiiable water l~vel ~AW~ of an aqueous li~uid containing the herbs or veget~bles. If the quanti~y of such electrolyte is sufficient to reduce the AW-value enough, no further stabilization step is necessary. Thus, if the AW-value is below 0.9, preferably below 0.85 and still more preferably below 0.8, drying may be accomplished without further treatment~

Sodium chloride is the preferred electrolyte for this purposel although calcium chloride is also ef~ectivë. The problem inherent in this approach, however, lies in the high levels of such electrolytes which must be employed if adequate stabili2aticn is to be achieved solely in this manner, De-pending on the nature of the aromatic plant~ its natural water content and the like, the amount of electrolyte required may vary from about 25~ to as much as 300% by weight of the plant.
dry matter. Aromatic plants dried in this manner may not be suitable for some uses, as the electrolyte may be considered annoying~ Further~ such a preparation may be proscribed where low sodium diets are necessary~

; This problem may be avoided by replacing part or even all of the electrolyte with other carriers. Sugars, which may optionally be hydrogenated r are particularly useful for this purpose, and mixtures of salt and sugars~ when used in connec-v tion with vacuum drying, are particularly preferred becau ethe procedure is simple and provides particularly good flavor preservation.

Optionally~ the salt content of the products of this invention may be kept low or eliminated by replacing the ele~-trolyte carrier wholly or partially by protein(s) and/or optionally hydrogenated oligo~ and/or polysaccharides, option-ally hydrogenated maltopolysaccharides, more preferably malto-dextrins, pregelatinized starch and/or so-called soluble or thin-boiling starch. In this case care should be ~ken, as already noted, to ensure that where little or no electrolyte is added the necessary thermal treatment is carried out ~o stabili~e flavor and-color.

This thermal treatment involves a fast and uniform heating of the aromatic plant. The aromatiç plant is firs~
mixed with a carrier, such as a carbohydrate~ protein and/or caseinate, together with very little water~ The resulting viscous liquid will uniformly encapsulate the aromatic plant particles. This method provides a shear-stable dried product which, probably due to an "encapsulating effect~, shows a high degree of storage stability. In addition, an exact, uniform and precise temperature control is possible during the thermal treatment because the viscous liquid ensures good heat trans~erD

_ g _ Carriers which have proved to be particularly suitable for this embodiment of the invention are optionally hydrogenated maltopolysaccharides like maltodextrin and pregelatinized starch as ~ell as, in particular, so-called soluble, liquefied or thin-boiling starches.

It has also been found to be advantageous to buffer the mixture to be dried by adding other alkaline and/or alkaline earth salt(s) of inorganic and/or organic acids, in particular monosod.ium glutamate, sodium citrate, a lactatev carbonate andjor phosphate, and/or a protein~ in particular albumin, and/or ~ caseinate~ The p~ of the cell liquor of the aromatic plan~(s), which is normally within a natural ran~e of from about

4 to 5~ and tends to go down in the process of dryin~. It has been found to be advantageous to raise the pH to range ~rom 4~5 to 7~5, preferably from 5.0 to 7.0 and more pre~erably from

5.4 to 6.7, and maintain the p~ within this range during ~he drying procesæ~ This appears to provide increased sta~ilization with regard to flavor and, in particul~r, colorO

. A substance that has proved to be particularly advantageous for this purpose is monosodium glutamate which also provides the finished dried aromatic plant products with its previously known taste-intensifying properties~

It is noted here that some of the starting materials des-cribed above as being suitable for use in the invention may haYe several functions at the same time~ Most of the above-mentioned buffers, for instance, are also carriers.

On the other hand, it is possible to have the ~unction of carrier fulfilled by several substances at the same time.
It is preferable as a rule to employ such mixtures.

~ his is exemplified by the following batch proportions, which have proved to be excellent for embodiments involving electrolyte carriers (parts by weight):

Fresh ~erb Salt Sugar MSG

With other types of carriers, in particular, so-called ~soluble starch" (e.g. SNOWPLAKE(R~ 6598, a product of Maizena ~;mbH) the advantages of using mixtures as carriers are not a~
apparent. It is s~iIl preferable, however, to add small amounts of salt and monosodium glutamate to the mixture that is to be dried I

As far as drying itself is concerned, it is possible, in principle, to apply any of .the ~ommon drying processes for the.purposes of this invention, but vacuum drying has thus far been found to yield the best results.

With this * pe of drying it is recommended to maintain a layer thickness of drying material of about 20 to 30 mm and to dry the product down to a residual moirture of 2 to 3%, at a temperature of about 60~C. ~t is also advantageous to stop heating the material during the last third of the drying period, thereby allowirlg the material to gradually cool to about 40C.

Va~uum drying produces mostly solid blocks which are, however, easy to comminute.

The following examples will illustrate the practlce o~
the invention. The stabilization step ~i.e~ heating or combining with the electrolyte) took place wi hin 5 to lO hours of harvest ing where fresh aromatic plant products were used. The products resulting from the examples were all characterized by excellent flavors and colors, and were virtually indistinguishable ~rom fresh products.

.- Six hundred grams (60Qg) of fresh deseeded red bell pepper was first blanched in water at 90~C - 95C, 5ubsequently, the pepper was mixed with three hundred ~rams ( 300g~ of a conuner-~r~ cially available protein ( "Seralbin" ) containing sixty-~ive per~
cent (65%) by weight whey protein and twenty percent (20%) lactose,.
and comminuted for 2 to 3 minutes in a laboratory cutterO The mix~ure was then vacuum dried in a layer of two to three centi-meters (2 to 3 cm). The temperature of the heatin~ plate was ~ ~racQe rV1a~/~

11''3~

60C, the pressure was about ~even millimeters of mercury 17~m ~9~, and the drying ~ime was about 6 hours.

The dried product obtained was then grated to the de~ired particle size, and compared favorably to the fresh pepper.

Six hundred grams (600g) of fresh deseeded red bell pepper were blanched in water a~ 90C and subsequently mixed with three hundred grams ~3GOg) of sodium caseinate, The mixture obtained was then filled in tray~ and further processed in the same manner as in Example 1. The final product compared favorably to the fres~ pepper.

Fresh parsley leaves were blanched for 1 minute in a boiling solution of 100 parts by weight sucrose in 100 parts water~ After draining off the excess liquid, the blanched parsley was dried in the same manner as in Example 1. The dry product contained about 15 - 20~ by weight parsley dry substance, and compared favorably to the fresh product.

- One hundred kilograms (lOOkgj of commercially available deep-frozen basil was first tempered for twenty-four hours at -10C. Thirty-two kilograms (32kg) of sodium chloride, nine ~ 3~
kilograms (9kg) of monosodium glutamate and nin~ kilograms (9kg) of sucro~e were mixed in a laboratory cutter for thirty ~econds.
Then, fifty kilograms (50kg) of the basil were added and the mixing continued for anQther thirty seconds. Finally~ the re-maining fifty kilograms (50k~) of basil was added and mixing continued for an additional thirty to forty seconds. The basil thawed fully during the mixing.

The mixture, in portions of appr~ximately five kilograms (5kg) each, was spread onto plastic trays in layers approximately three centimeters (3cm) deep. The product was then vacuum dried, with the heating plates at a constant temperature of SOC, for a period of fifteen to seventeen hours. During the drying process the pressure was initially ~et at twenty millimeters of mercury (20mm~g) and was reduced to about seven to ten milli-meters of mercury (7 to lOmmHg) during the last stage of the drying.

The resulting dried herb mix contained about two to three percent (2 to 3%) moisture; and was in the form of cakeg.
These cakes were easily broken to the desired particle size in a Frewitt strainer. The final product was appro~imately thirty-nine to forty percent (39 to 40~) by weight basil dry su~stance, and compared favorably to fresh product.

3~

One hundred grams (lOOg) of fresh lovage leaves were rinsed wi~h resh water and drained. Then, twelve hundred grams (1200g~ of sodium chloride was placed in a laboratory cutter and the washed lovage leaves were added while the cutter was running on low speed. Mixing continued for about three minutes.

The mixture was then spread onto a plastic tray in a layer approximately ~wo centimeters (2cm) deep, and dried for --seven hours under a vacuum of ten millimeters of mercury (lOmmHg3O
The heating plate was kept at a constant temperature of about 65C.

The final product was approximately seven and seven-tenths percent (7.7%) by weight lovage dry substance, and compared favorably to the fresh product.

Six hundred grams (600g) of fresh parsley leaves were washed with fresh water and drained. ~hen, two hundred grams ~200g) of sodium chloride and fifty grams (50g) of sodium caseinate were pre-mixed in a laboratory outter. The washed and drained parsley was then added while the cutter was still running and mixing continued for about two to three minutes.

The mixture was then dried for about five hours according to the conditions set out in Example 1.

3:~31~

The final product was approximately thirty-five to thirty-six percent (35 to 36~) by weight parsley dry substance, and compared favorably to the fresh product.

Other features, advantages and specific embodiment~ of this invention will become readily apparent to those exerci~ing ordinary skill in the art after readiny the foregoing disclo~
sure~. These specific embodiments are within the scope o~ the claimed subject matter unless otherwise expressly indicated to the contrary. Moreover, while specific embodiments of this invention have been described in considerable ~etail, variations and modifications of these embodiments can be effected without departing from the spirit and scope of this invention as dis closed and claimed.

. - 16 -

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for the preparation of a flowable, dried aromatic plant product having an aromatic plant component and an edible, water-soluble carrier component, which process comprises the steps of:

(a) treating an aromatic plant component comprised of one or more comminuted aromatic herbs or vegetables in at least one stabilizing step selected from the group consisting of:
(1) mixing said aromatic plant component with an electrolyte selected from the group consisting of alkaline and alkaline earth salts of organic and inorganic acids, and (2) quickly heating said aromatic plant component to a temperature of from 50~°C to 150°C and maintaining said temperature for a period of from 2 seconds to 1 hour, to form a stabilized component;

(b) adding to said stabilized component and uniformly mixing therewith a carrier component in a proportion which will yield from 10 to 90 percent by weight of the total dry matter of the final dried product, which carrier component comprises at least one edible, water-soluble compound selected from the group consisting of:

(1) an electrolyte selected from the group consisting of alkaline and alkaline earth salts of organic and inorganic acids, all or any portion of which may have been previously added in step (a)(1), (2) proteins, and (3) hydrogenated and non-hydrogenated carbohydrates, to produce a stabilized plant/carrier mixture; and (c) drying the stabilized plant/carrier mixture for a sufficient period of time to produce a flowable, dried aromatic plant product in such a manner that the temperature of the mixture is not permitted to exceed 70°C.

2. The process of claim 1 wherein the aromatic plant com-ponent comprises a freshly harvested aromatic herb or vegetable and the stabilization step is effected no later than 12 hours after havesting and no later than 4 hours after comminution.

3. The process of claim 1 wherein the aromatic plant component comprises a fresh-frozen aromatic herb or vegetable and the stabilization step is effected immediately upon thawing.

4. The process of claim 1 further characterized in that the stabilized plant/carrier mixture is buffered to a pH-value in the range of 4.5 to 7.5.

5. The process of claim 4 further characterized in that the stabilized plant/carrier mixture is buffered to a pH-value in the range of 5.4 to 7Ø

6. The process of claim 5 further characterized in that the stabilized plant/carrier mixture is buffered to a pH-value in the range of 5.4 to 6.7.

7. A flowable, dried aromatic plant product prepared by the process of claim 1.

8. The flowable, dried aromatic plant product of claim 7 wherein the aromatic plant component is chosen, at least in part, from the group consisting of basil, parsley, lovage, dill, chives, chervil, sweet marjoram, thyme, celery, pakrika, fennel and leek.

9. The flowable, dried aromatic plant product of claim 7, wherein the carrier component comprises, at least in part sodium or potassium chloride in the amount of twenty-five to three hundred percent (25 to 300%) by weight based on plant dry matter.

10. The flowable, dried aromatic plant product of claim 7, wherein the carrier component comprises, at least in part, at least one soluble maltopolysaccharide.

11. The flowable, dried aromatic plant product of claim 10, wherein the maltopolysaccharide is hydrogenated.

12. The flowable, dried aromatic plant product of claim 10 wherein the maltopolysaccharide is chosen from the group consisting of maltodextrin, soluble starch, thin-boiling starch and pregelatinized starch.

13. The flowable, dried aromatic plant product of claim 7 wherein the carrier component comprises, at least in part, an electrolyte selected from the group consisting of mono-sodium glutamate, sodium citrate, and lactate, carbonate and phosphate.

14. The flowable, dried aromatic plant product of claim 7 wherein the carrier component comprises, at least in part, a protein selected from the group consisting of albumin and a caseinate.