Chapter 3
Process Flavors and Precursor Systems Commercial Preparation and Use Charles H . Manley
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Takasago International Corporation (USA), 100 Green Street, Teterboro, N J 07608
Flavors developed by using thermal treatment of selected precursor materials have become standard commercial flavors sold around the world. More than thirty years ago the f i r s t prototype based on the modification of simple hydrolyzed vegetable proteins (HVP) with various amino acids and sugar led the way to the current practice of the industry. Today, the degree of our current knowledge, as reinforced by the chapters in this book, has allowed precise selection of the precursors and processing conditions needed to create high quality flavors. European regulators are establishing a special class of flavors, designated as "process flavors," and are currently establishing regulatory guidelines for the class. The class of flavors represents a material that i s closer to food stuffs in their composition than traditional flavors and, therefore, present a unique problem in establishing regulatory standards. Man has long used thermal processing or cooking of food as a means to develop a desirable flavor in his food stuff. In the last 25 years the s c i e n t i f i c community has discovered the chemical mechanisms and identified the precursor chemicals that selectively give r i s e to aromas and taste similar to those of cooked foods. The thermal generation of aroma has been the subject of many s c i e n t i f i c papers and symposia and has enabled flavor industry to create a line of flavors known as process flavors < 1> 2).
0097-6156/94/0543-0016$06.00/0 © 1994 American Chemical Society Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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3. MANLEY
Process Flavors and Precursor Systems
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Process flavors are flavor c r e a t i o n s w h i c h mimic c o o k e d f o o d f l a v o r s , b u t a r e u s e d a t a low d o s a g e because of the high concentration of the f l a v o r components. The f l a v o r and aroma profile may be r e m i n i s c e n t o f a r o a s t e d c h i c k e n , a Dutch c h o c o l a t e o r any f o o d p r o d u c t w h i c h h a s been a l t e r e d o r c r e a t e d by heat. The s o p h i s t i c a t i o n and demands f o r t h e s e f l a v o r s have steadily increased over the years as flavor s c i e n c e , f o o d t e c h n o l o g y and t h e d e v e l o p m e n t o f new f o o d products have expanded. This product class currently represents significant business growth and creative development opportunity f o r the Flavor Industry. I t a l s o r e p r e s e n t s a c h a l l e n g e ; l i k e f o o d s t u f f s themselves, problems e x i s t i n i d e n t i f y i n g and d e f i n i n g t h e p r o d u c t and e v a l u a t i n g i t s s a f e t y i n u s e . Flavor Manufacturing
Practices
For the last ten years the Flavor and Extract Manufacturers' Association (FEMA) h a s had a w o r k i n g c o m m i t t e e w h i c h h a s d e a l t w i t h many b a s i c i s s u e s r e l a t e d to process flavors. This c o m m i t t e e was i n s t r u m e n t a l , by working through the I n t e r n a t i o n a l Organization of Flavor I n d u s t r i e s (IOFI), i n establishing a guideline f o r the manufacturer of process f l a v o r s . That g u i d e l i n e i s p a r t o f I O F I ' s Code o f P r a c t i c e s and t h e b a s i s o f t h e c u r r e n t European Industry/Government d i s c u s s i o n s r e l a t e d to the regulation of process f l a v o r s i n Europe ( 3 ) . T h e s e f l a v o r s have been d e s i g n a t e d a s a s e p a r a t e c l a s s o f f l a v o r known a s " p r o c e s s f l a v o r s . " Unlike the basic t e r m " f l a v o r " which r e p r e s e n t s t h e e x t r a c t s o f b o t a n i c a l or food m a t e r i a l s o r pure a r o m a t i c c h e m i c a l s approved f o r f l a v o r use, t h e " p r o c e s s f l a v o r s " a r e i d e n t i f i e d a s complex m i x t u r e s w h i c h have been c o n v e r t e d t o f l a v o r s by heat p r o c e s s i n g s t e p ( s ) . In t h e U n i t e d States, the focus on t h e d e f i n i t i o n and r e g u l a t i o n o f p r o c e s s f l a v o r s h a s n o t been a s c l e a r . They a r e c o n s i d e r e d f l a v o r s , and t h e i r u s e i n f o o d i s based upon t h e assumed s a f e t y of the f l a v o r and i t s relationship t o foods. Because of the complexity of process flavors, i t i s more related t o f o o d s and, therefore, is i n contrast to safety reviews and evaluations given t o pure chemicals used to flavor foods. These traditional flavor materials are the so-called "GRAS" or g e n e r a l l y recognized as s a f e m a t e r i a l s used by t h e USA m a n u f a c t u r e r s of a r t i f i c i a l flavors. To g i v e t h e r e a d e r a b e t t e r p e r s p e c t i v e o f what a process f l a v o r i s and how i t f u n c t i o n s , l e t u s draw a n a l o g i e s o f p r i o r a r t and t h e p r a c t i c e o f t h e c h e f and Grandma. The c h e m i c a l bases of f l a v o r c r e a t e d by t h e r m a l t r e a t m e n t w i l l be t h e f o c u s o f many c h a p t e r s i n this book and h a s been covered i n many previous symposia. The c o m m e r c i a l r e a s o n s f o r t h e u s e o f
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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THERMALLY GENERATED FLAVORS
preparing fine sauces and g r a v i e s goes back to the b e g i n n i n g o f t h e g r e a t c u l i n a r y s c h o o l s o f E u r o p e and the Orient. I t was t h e c h e f who e x p e r i m e n t e d w i t h many i n g r e d i e n t s t o produce a f l a v o r p r o f i l e which f i t t h e n e e d s o f t h e e n t r e e he was s e r v i n g . The c u l i n a r y a r t t o c h o s e t h e p r o p e r i n g r e d i e n t and c o o k i n g c o n d i t i o n s h a s led to the great gustatory delights such as Bearnaise sauce and o t h e r great s a u c e s o f Germany, F r a n c e and C h i n a . They a r e a l l b a s e d on t h e d e v e l o p m e n t o f f l a v o r s by t h e c a r e f u l s e l e c t i o n and p r o c e s s i n g o f i n g r e d i e n t . So t o o a r e t h e s a u c e s and g r a v i e s c r e a t e d by Grandma o r today's homecooks and t h e Food Technologists of the world's food industry. A l l this creativity was b a s e d upon i n t u i t i o n a true a r t form. T h i s symposium, and others l i k e i t , will d i s c u s s t h e s c i e n t i f i c knowledge which identifies t h e key i n g r e d i e n t s and p r o c e s s i n g temperature and t i m e needed to develop that aromatic b l e n d o f v o l a t i l e s u b s t a n c e s t h a t we c a l l f l a v o r . F i g u r e 1 shows t h a t a c h e f may u s e i n g r e d i e n t s I t o 110 to create the gustatory delight while the food product developer o r Grandma a t home has a s i m p l e r a p p r o a c h and knows that selected ingredients I, 14, 15 and 110 a r e key t o c r e a t i n g a u s e f u l , although not award-winning, sauce. They use those i n g r e d i e n t s and p r o c e s s , o r "cook" them a t a given temperature for a g i v e n time. The s c i e n t i s t now l o o k s a t what h a s been c r e a t e d and i s o l a t e s t h e key a r o m a t i c components w h i c h make up the flavor. He or she a l s o studies the chemical mechanisms and p r e c u r s o r c h e m i c a l s which g i v e rise to the v o l a t i l e a r o m a t i c components. By l e g a l d e f i n i t i o n , f l a v o r s a r e i n g r e d i e n t s added t o f o o d a t low q u a n t i t i e s for flavor effect and make l i t t l e o r no s i g n i f i c a n t contribution to the n u t r i t i v e content of t h e food. Therefore, the f l a v o r chemist w i l l f o c u s on r e c r e a t i n g t h e f l a v o r p r o f i l e by t h e u s e o f v e r y s p e c i f i c c h e m i c a l precursors or food components. The f l a v o r c h e m i s t knows t h a t c e r t a i n key i n g r e d i e n t s o r i s o l a t e s f o r t h e s e i n g r e d i e n t s used by t h e c h e f o r Grandma w i l l create a "flavor" which may be u s e d by t h e f o o d industry to enhance t h e q u a l i t y o f t h e prepared food. He o r s h e , t h e r e f o r e , c h o o s e s I, a component o f 13, 14 and 15 and 110 t o make t h e f l a v o r . Such a f l a v o r may l o o k l i k e t h i s qualitative formulation: • Heat e x t r a c t • Onion e x t r a c t • Cystein + Thiamine + Glucose + Beef F a t « Heated a t 120°C f o r 60 m i n u t e s at a c o n c e n t r a t i o n o f 70% s o l i d s . * The product i s a strong meat-like aroma.
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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3. MANLEY
Process Flavors and Precursor Systems
This i s the e v o l u t i o n path from a purely empirical approach (the a r t of cooking) to the s c i e n t i f i c approach (the s c i e n c e of c r e a t i n g a f l a v o r ) . The classical approach for making a "flavor" r e q u i r e s t h e use o f n a t u r a l extracts or distillates and/or synthetic aromatic chemicals (typically those found i n nature). These m a t e r i a l s are blended t o g e t h e r to c r e a t e the f l a v o r p r o f i l e . However, i t i s n e a r l y i m p o s s i b l e to c r e a t e the c o r r e c t f l a v o r p r o f i l e of a cooked, roasted food without s u b j e c t i n g i n g r e d i e n t s or precursors to a thermal treatment. The classical approach allows the f l a v o r chemist t o use m a t e r i a l s which a r e pure (synthetic chemicals) or are natural e x t r a c t s o r d i s t i l l a t e s w h i c h have been u s e d f o r some t i m e and a r e c o n s i d e r e d s a f e f o r use. T h e s e m a t e r i a l s a r e c o n s i d e r e d by t h e 1958 A c t a s " g e n e r a l l y r e c o g n i z e d a s s a f e " o r GRAS. Dr. L a w r e n c e L i n ' s c h a p t e r i n t h i s book and h i s p r e v i o u s p u b l i c a t i o n h a v e i n d i c a t e d the p r i n c i p a l s o f t h e GRAS c o n c e p t ( 4 ) . Our p r o c e s s f l a v o r is different from these well known s u b s t a n c e s . Our p r o c e s s f l a v o r becomes u n i q u e , a s a m o d i f i e d s a u c e o r gravy. It i s a complex mixture with substantially different characterization from its individual components, and as prepared foods, i t would be difficult to d e f i n e the product except i t s r e c i p e or formulation p r i o r to processing. The
GRAS
Concept
In 1958 t h e Food A d d i t i v e s Amendment t o t h e F e d e r a l Food, Drug and C o s m e t i c A c t o f 1938 c r e a t e d a c o n c e p t o f e v a l u a t i n g t h e s a f e t y o f s u b s t a n c e s added t o f o o d s . The Act d e f i n e s a food additive as any substance whose i n t e n d e d u s e r e s u l t s i n i t s becoming a component o f f o o d or otherwise a f f e c t i n g the c h a r a c t e r i s t i c s of food i f the substance is not "generally recognized, among e x p e r t s q u a l i f i e d by s c i e n t i f i c t r a i n i n g and e x p e r i e n c e t o e v a l u a t e i t s s a f e t y , a s h a v i n g been a d e q u a t e l y shown through scientific procedures to be s a f e under the c o n d i t i o n o f i t s i n t e n d e d use. " This p r o v i s i o n i s the c o n c e p t e x c e p t i o n t h a t p l a y e d a major r o l e i n t h e s a f e t y e v a l u a t i o n o f f l a v o r i n g s u b s t a n c e s u s e d t o make f l a v o r s (5). C l a s s i c a l f l a v o r i n g components a r e a u n i q u e s e t o f s u b s t a n c e s t h a t f i t e a s i l y i n t o t h e GRAS c o n c e p t . They a r e t y p i c a l l y u s e d a t l e v e l s below 10 ppm i n f o o d and i n many c a s e s less than 1 ppm. T h i s i s an order of magnitude less than traditional food additives (6). T y p i c a l t h r e s h o l d l e v e l s f o r v a r i o u s components known t o o c c u r i n p r o c e s s f l a v o r s i s shown i n T a b l e I. The l e v e l of the use of f l a v o r s and flavoring components are u s u a l l y s e l f - l i m i t i n g because of the i n t e n s i t y of the p r o d u c t . Most o f t h e m a t e r i a l s a r e e x t r a c t s o f f o o d s ,
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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20
THERMALLY GENERATED FLAVORS
CHEF...
I - INGREDIENTS
• 1-1 • I-2 • I-3... l-n
(COOK)
»
SAUCES
GRANDMA OR FOOD TECHNOLOGIST... CONCENTRATED SAUCE
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. |-1 • |-4 • I-6 • 1-12 (PROCESS)
(PREPARED FOOD) FLAVOR CHEMIST... * 1-1 • I-4 AND COMPONENTS OF I-2, I-3, I-5 AND 1-12 (HIGH TEMP)
• FLAVOR
Figure 1. Use of ingredients to produce flavors.
Table I. Threshold values of some flavor components found in cooked meats PPM
PPB
PPT COMPOUND CLASS THIAZOLINES PYRAZINES FURANONES FURANS ALDEHYDES POLY SULFIDES THIOPHENES 1 1 Mill
1.0
10
1 1 Mill
i i mill
100
i i mm
1.0
i i iiilu
10
l IIIIIII
100
i i
inn
1 i mill
i i
1.0 10
THRESHOLD RANGES
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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Process Flavors and Precursor Systems
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herbs or spices or are chemicals which a r e found i n those foods, herbs or s p i c e s . These f a c t o r s put f l a v o r s i n t o a s p e c i a l c l a s s of i n g r e d i e n t s used i n f o o d s and s u g g e s t a much lower exposure and/or r i s k t o consumers than the functional food additives. The GRAS concept as p r a c t i c e d by t h e f l a v o r industry requires that a panel of experts review c e r t a i n toxicology data on c h e m i c a l components and d e t e r m i n e by knowledge o f t h e additives' structure, available toxicology d a t a and e s t i m a t e d human e x p o s u r e i f t h e r e i s r e a s o n a b l e c o n c e r n f o r t h e s a f e t y o f t h e consumer a t t h e i n t e n d e d u s e o f the substance. While t h i s procedure does n o t g u a r a n t e e c o m p l e t e s a f e t y , i t d o e s e s t a b l i s h a p r e s u m p t i o n o f no harm ( 7 ) . Congress, when i t established t h e 1958 Food A d d i t i v e s Amendment t o t h e 1938 Food Drug and C o s m e t i c Act, recognized the i m p o s s i b i l i t y of determining with absolute certainty t h a t no harm s h a l l r e s u l t from t h e i n t e n d e d u s e o f an a d d i t i v e . Therefore, the l e g i s l a t i o n did not follow a standard of absolute safety. There e x i s t s a l i s t o f GRAS m a t e r i a l s i n t h e Food and Drug A d m i n i s t r a t i o n r e g u l a t i o n u n d e r T i t l e 21 o f t h e Code of Federal Regulation (CFR) ( 8 ) . The f l a v o r i n d u s t r y a l s o m a i n t a i n s a l i s t o f s u b s t a n c e s a p p r o v e d by t h e F l a v o r and E x t r a c t M a n u f a c t u r e r s ' A s s o c i a t i o n (FEMA) Expert Panel (9). B o t h l i s t s a r e u s e d by t h e i n d u s t r y to s e l e c t m a t e r i a l s f o r use i n c r e a t i n g f l a v o r . Both l i s t s a r e considered t o c o n t a i n l e g a l substances f o r use in t h e American food system. As n o t e d , the c l a s s i c f l a v o r s a r e compounds/mixtures of these materials. Just as f o o d s a r e complex mixtures o f i n g r e d i e n t s so, too, a r e f l a v o r s . The f i n a l f l a v o r i s c o n s i d e r e d t o be s a f e and l e g a l b e c a u s e i t i s composed o f m a t e r i a l s w h i c h a r e c o n s i d e r e d t o p r o d u c e no harm a t t h e i n t e n d e d u s e . The
D e f i n i t i o n of a Process
Flavor
In t h e USA a l l flavors are considered and titled "flavors'* with no r e g a r d on how they a r e produced. However, i n Europe, t h e E u r o p e a n Community (EC) h a s i d e n t i f i e d and t i t l e d a number o f t y p e s o f f l a v o r s b a s e d on p r o c e s s i n g , i n c l u d i n g " p r o c e s s flavors" and "smoked flavors". The EC definition of process flavors i d e n t i f i e s the types o f m a t e r i a l s which may be u s e d a s p r e c u r s o r s and t h e t i m e / t e m p e r a t u r e treatment that the mixture may be g i v e n . Table II presents t h e key features of the International Organization of Flavor Industries' (IOFI) guideline f o r the manufacture o f process f l a v o r s . I t i s i n t e r e s t i n g t o note that the United State Department of Agriculture in a final regulation issued March 1991 identified certain materials used t o make process flavors a s component w h i c h need t o be i d e n t i f i e d i n t h e l a b e l s t a t e m e n t (10.). Note, however, t h a t t h e USDA d i d n o t s e t a g u i d e l i n e f o r
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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manufacture, but e s t a b l i s h e s labeling criteria for m a t e r i a l s used t o produce the process f l a v o r . Table I I I g i v e s t h e key f e a t u r e s o f t h a t r e g u l a t i o n . Therefore, a process f l a v o r i s reasonably unique as a f l a v o r s i n c e i t has i t s f l a v o r p r o f i l e developed a f t e r it h a s been compounded and s u b j e c t e d to cooking or roasting conditions. Process f l a v o r s are sold to the food industry a s t h e f l a v o r , whereas microwave f l a v o r may be sold as precursor mixture prior to the development of f l a v o r . The h e a t / e n e r g y e f f e c t s of the microwave oven would produce and r e l e a s e the f i n a l f l a v o r . M i c r o w a v e f l a v o r " p r e c u r s o r s " s y s t e m s a r e needed in c e r t a i n prepared f o o d t o c r e a t e t h e aroma p r o f i l e which would n o t be d e v e l o p e d because of t h e lower t e m p e r a t u r e and s h o r t e r t i m e o f t h e microwave t r e a t m e n t . Other c h a p t e r s i n t h e book w i l l review the chemical basis and i n d i c a t e t h e c h e m i s t r y f o r p r o d u c i n g good f l a v o r p r o f i l e s from p r e c u r s o r s . These f l a v o r s e x i s t t o g i v e prepared f o o d s a cooked or roasted profile, f o r example, i n d r y mix i n s t a n t soups. Add h o t w a t e r and e n j o y t h e f l a v o r . Or s t a r t from scratch where the precursors (ingredients) are added and t h e n cooked t o d e v e l o p t h e f l a v o r . The r a p i d p a c e o f o u r modern l i v e s h a s mandated t h e f o r m e r method as t h e f o o d o f c o n v e n i e n c e . T h i s i s the basis of our "ready-to-eat" s o c i e t y - i n s t a n t prepared foods. Process f l a v o r s and m i c r o w a v e p r o d u c t s were i n v e n t e d t o s a t i s f y t h a t need. L i k e t h e concept of food s a f e t y accepts the b e l i e f that, i f the i n d i v i d u a l components a r e s a f e , t h e n t h e f i n a l p r e p a r e d f o o d s h o u l d a l s o be s a f e . Then t h e s a f e t y concept a l s o f i t s t h e development o f p r o c e s s f l a v o r s . Modern S a f e t y E v a l u a t i o n The requirements of the food law i s that the manufacturer does not i n t r o d u c e a p o t e n t i a l hazardous material into the food system. This p r o b l e m h a s been demonstrated a number of times where certain c o n s t i t u e n t s o f a f o o d have been f o u n d t o be a h a z a r d . For example, aflatoxins i n peanuts, nitrosamins i n malted grain f o r beer production, and s o l a n i n e i n potatoes, t o mention o n l y a few p r o m i n e n t c a s e s . Upon f i n d i n g a substance or substances i n a food that possess a h a z a r d t o man, an e f f o r t must be made t o remove t h e hazard or lower t o a l e v e l which e x p e r t s would a g r e e t h a t i t would p o s s e s s no g e n e r a l t h r e a t t o t h e consumer. In t h e c a s e s above, p r o c e s s i n g c h a n g e s have been made s o that the foods do n o t r e p r e s e n t a problem. Regulatory groups around t h e world w i l l s e t l e v e l s f o r these types of c o n s t i t u e n t s found i n foods. T h i s i s also true of food a d d i t i v e s , even when the trace contaminants a r e recognized as c a r c i n o g e n s while the additive has not been shown t o have t h e s e p r o p e r t i e s .
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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Process Flavors and Precursor Systems
Table II. Process flavor manufacture guidelines
• WITH THE FOLLOWING EXCEPTIONS, AND UNDER THE CONDITIONS DESCRIBED BELOW, INGREDIENTS CONSUMED IN THE REACTION MAY BE LISTED COLLECTIVELY AS REACTION (PROCESS) FLAVORS
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/
EXCEPTIONS: • ALL INGREDIENTS OF ANIMAL ORIGIN • ALL NON-ANIMAL PROTEINACEOUS SUBSTANCES (INCLUDING MSG HVP AND AYE) • THIAMINE HYDROCHLORIDE, SALT AND C O M P L E X CARBOHYDRATES • ANY OTHER INGREDIENT THAT IS NOT CONSUMED IN THE REACTION
7 CONDITIONS: • REACTION CONTAINS AMINO ACIDS(S), REDUCING SUGAR(S), AND PROTEIN SUBSTRATES • TREATED WITH HEAT 100 C OR GREATER FOR A MINIMUM OF 15 MINUTES
Table III. U S D A regulation for ingredient labeling • INTERNATIONAL ORGANIZATION OF FLAVOR INDUSTRIES (IOFI) CODE OF PRACTICE GUIDELINES- P R O C E S S FLAVORS: • ARE PRODUCTS OF A MIXTURE PREPARED FOR ITS FLAVORING PROPERTIES • ARE PRODUCED FROM INGREDIENTS OR MIXTURES OF INGREDIENTS WHICH ARE THEMSELVES PERMITTED FOR USE IN F O O D S T U F F S • OR ARE NATURALLY IN FOODSTUFFS • OR ARE PERMITTED FOR USE IN P R O C E S S FLAVORS • AND ARE GENERATED BY A PROCESS USED FOR THE PREPARATION OF FOODS FOR HUMAN CONSUMPTION • THE DEFINITION DOES NOT APPLY TO E X T R A C T S , P R O C E S S E D NATURAL FOOD SUBSTANCES OR MIXTURES OF FLAVORING SUBSTANCES
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
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THERMALLY GENERATED FLAVORS
Recently c e r t a i n c h l o r i n a t e d g l y c e r i d e s have been found hydrolyzed vegetable proteins (HVP). HVP's have been used f o r more than 100 y e a r s to add m e a t - l i k e flavor to prepared foods. They r e p r e s e n t one of the e a r l i e s t f o r m s o f p r o c e s s f l a v o r s , and t h e y a r e composed o f amino a c i d s g e n e r a t e d by t h e h y d r o l y s i s o f v e g e t a b l e p r o t e i n w i t h HC1. The h e a t u s e d t o h y d r o l y z e t h e p r o t e i n a l s o p r o d u c e s a r o a s t - l i k e f l a v o r c h a r a c t e r (1J^). D u r i n g t h e r e a c t i o n t h e HC1 c h l o r i n a t e s g l y c e r i n e which r e s u l t s from trace amounts of fats found in the vegetable p r o t e i n . Changes i n t h e method o f p r o c e s s i n g w i l l l o w e r t h e amount o f t h e c h l o r i n a t e d g l y c e r i n e t o a s a f e l e v e l . Some E u r o p e a n c o u n t r i e s have s e t 50 ppm a s a s a f e l e v e l . A number o f r e s e a r c h e r s have r e c e n t l y r e p o r t e d t h a t certain amino acids, specifically creatine and c r e a t i n i n e , form a number of h e t e r o c y c l i c a m i n e s when heated i n the presence of other amino acids. These substituted i m i d a z o q u i n o l i n e s have been f o u n d t o be genotoxic and carcinogenic (12.). Creatine and c r e a t i n i n e are found i n muscle p r o t e i n and may permit the development of the h e t e r o c y c l i c a m i n e s when meat i s cooked or p r o c e s s f l a v o r s , based on meat e x t r a c t s or these s p e c i f i c amino acids, are prepared. The f l a v o r i n d u s t r y r e p o r t e d , at the l a s t T o x i c o l o g y Forum h e l d i n Aspen, C o l o r a d o , t h a t a j o i n t F l a v o r I n d u s t r y / F o o d Drug Administration Task F o r c e was s t u d y i n g the l e v e l s of h e t e r o c y c l i c a m i n e s i n p r o c e s s f l a v o r s by e s t a b l i s h i n g a standard analytical method via HPLC for the q u a n t i f i c a t i o n of the h e t e r o c y c l i c a m i n e s (13.). Such a method w i l l allow the FDA t o d e t e r m i n e whether u n s a f e l e v e l s of h e t e r o c y c l i c amines exist in process f l a v o r and i f so, t o e s t a b l i s h g u i d e l i n e s as has been done i n the past. Conclusions Process flavors and precursor systems r e p r e s e n t new s c i e n t i f i c a d v a n c e s on t h e o l d c u l i n a r y a r t o f p r e p a r i n g f i n e s a u c e s , g r a v i e s and o t h e r s i m i l a r f o o d s . J u s t as a f o o d r e p r e s e n t s a complex m i x t u r e o f c h e m i c a l s u b s t a n c e s so, t o o , do p r o c e s s f l a v o r s . They r e p r e s e n t a new class of f l a v o r s and are being designated also i n Europe. Guidelines exist for t h e i r m a n u f a c t u r e and t h e EC w i l l be a d o p t i n g them as o f f i c i a l standard procedures f o r t h i s c l a s s of f l a v o r s . As a n o t h e r example of r e g u l a t i n g a "new" food, the FDA Commissioner, Dr. David Kessler, has recently proposed t h a t f o o d s c r e a t e d by f o o d b i o t e c h n o l o g y need not undergo a premarket review unless the new f o o d r e p r e s e n t s some type of p o s s i b l e hazard. The FDA has i n d i c a t e d t h e s e new f o o d s s h o u l d be r e g u l a t e d u n d e r i t s postmarket authority which leave the premarket evaluation of safety and nutritional concerns to industry with guidelines established by the a d m i n i s t r a t i o n (14).
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.
3. MANLEY
Process Flavors and Precursor Systems
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Regulation of foods, new and old, and flavors based on food concepts such as process flavors are reasonably regulated by the same policy. Safety concerns, as noted, should be focused on the identification and evaluation of containment which may be considered hazardous to the consumer. Literature Cited
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1.
2.
3. 4. 5. 6. 7. 8. 9. 10. 11.
12. 13. 14.
Waller, G. R.; Feather, M.S. The Maillard Reaction in Foods and Nutrition; ACS Symposium Series No. 215; American Chemical Society: Washington, DC, 1983. Parliment, T.H.; McGorrin, R . J . ; Ho, C-T. Thermal Generation of Aromas; ACS Symposium Series No. 409; American Chemical Society: Washington, DC, 1989. Code of Practice; 2nd Ed., International Organization of the Flavor Industry: Geneva, Switzerland, 1990. Lin, L . J . Food and Drug Cosmetic Law Journal. 1991, 46, pp 877-884. Woods, L . A . ; Doull, J. Regulatory Toxicol. Pharmicol. 1991; 14, 48. Fors, S. Servics-serie, 1981; The Swedish Food Institute, Sweden Oser, B . L . ; Ford, R.A. Food Tech. November 1991, pp 84-97. Code of Federal Regulation (CFR), 21 Section 172.515 and 182.60. Flavor and Fragrance Materials 1991, Allured Publishing Co.: Wheaton, Il., 1991. Fed. Regis. Vol.. March 1, 1991. Manley, C.H.; McCann, J . S . ; Swaine, J r . , R.L. In Quality of Foods and Beverages Vol. 1,. G. Charalambous and G. Inglett (ed), Academic Press: New York, 1981; pp 61-82. Sugimura, T., Mutat. Res. 150: 33-41. Proc. of the Toxicology Forum 1992, Aspen, Co. Coulston, F . ; Kolbye, A.C. (Ed), Regulatory Toxicology and Pharmicology; December 1990, 12: s1-s190.
RECEIVED
January 8,1993
Parliment et al.; Thermally Generated Flavors ACS Symposium Series; American Chemical Society: Washington, DC, 1993.