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The f a t was decidedly yellow and rancid smelling - espec ia l ly on the controls. Mold gmwth was abundant and was present i n f a i r l y large amounts even on the shank portion. Penicil l ium expansum and Penicillium viridicatum again were the predominant fungi with Aspergil lus ruber and Aspergil lus repens a l so appearing as a r e s u l t of t he considerably lower water ac t iv i ty . only a few Bacillus, Micrococcus and yeasts were found on the in t e r io r . This would indicate t h a t the s a l t concentration and. decreased water a c t i v i t y were inh ib i tory t o a great extent.

No bac ter ia were found on the surface of t he hams while

Conclusions

On the basis of these findings, it may be concluded t h a t fungi do play a ro l e i n t h e preservation of aged sausages and hams. Their contribution t o re ten t ion of moisture and color has been noted f o r both types of meat. The use of molds i s in ten t iona l f o r many European gourmand sausages but i s inc identa l f o r most country cured hams.

Salami overgrovrn by molds develop an a t t r a c t i v e greyish white f e l t - l i k e surface t h a t pro tec ts the meat from spoilage fungi and serves a s a f a i r l y impermeable coating t o moisture vapor and oxygen transmission. A s a consequence, these sausages r e t a i n more moisture, develop more in- tense color, have reduced estraneous microbial growth and can be pre- served f o r longer t i nes without development of rancidi ty .

Hams cure s a t i s f a c t o r i l y without any mold a c t i v i t y but when these meats remain i n storage f o r 6-9 months and lose 25-30$ of t h e i r o r ig ina l weight, growth of Pen ic i l l i a and Asperg i l l i appear as a r e s u l t of t he reduced water ac t iv i ty . The f a t of these hams i s l e s s yellow and rancid than t h a t of meat f r e e of mold growth.

DR. BLUMER: O u r next speaker i s Director of Research of John Morrell and Company. So, he w i l l make a few remarks concerning the paper which was presented by Dr. Deibel. D r . Brown.

DR. BROkJN: Thank you, Tom. I t ' s always a pleasure t o be back and meet with you. Deibel ' s paper. minutes about some spec i f ic things t h a t we do t o control t h e microbial content of f inished products. slaughter ourselves, because we have ra ther good control from t h e l i v e animal a l l t h e way through t o the f inished product. of meats from outside; we c a l l these extra-purchase meats. We have our own intercompany spec i f ica t ion for these inccming neats. Now we found out long ago t h a t you can ' t give numbers t o your super- visory and operating people t o use. So, you don ' t report r e s u l t s t o them on these meats as so many per gram. You simply send them a report a f t e r t he m e a t has been properly sampled and the analysis has been made. You say t h a t it i s very good, good, questionable, or excessive. We

I was very much in te res ted i n hearing D r . This w i l l give me a chance t o t a l k t o you fo r a few

I won't t a l k about the animal we

But we buy a l o t

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th ink t h a t anything up t o t e n thousand should be c l a s s i f i ed a r e a l good product. one hundred thousand t o one million. If i t ' s over one mill ion, i t ' s excessive, and we want t o have something t o say about where the product i s f i n a l l y used. Another area t h a t we're qu i te concerned about i s the bac ter io logica l condition of food contact areas , Any place where the meat touches a piece of equipment, we're concerned about. l o t of work with swabs. t ha t , i f we use the same method of report ing here, t h i s a l so i s e f fec t ive . If we f ind l e s s than s ix microorganisms per square inch, we consider t h i s r e a l good. Six t o f i f t e e n we consider good. F i f teen t o seventy-five i s fair . i s excessive, and we need t o do some clean-up work. of course, r e l a t ive , and they, I'm sure, would not be the same ones t h a t our good f r iends from S w i f t and the r e s t of t h e meat industry would use, but I ' m sure they'd have a s imilar system.

Ten thousand t o a hundred thousand i s good; questionable i s

We do qui te a We take a swab of a square inch area. We f ind

Seventy-five t o th ree hundred i s poor. And more than three hundred These values are ,

We work on packaging material; we've establ ished standards fo r items l i k e cartons, paper, pan l i n e r s , can l i n e r s , l abe ls , various p l a s t i c bags, a l l t he films, o f f i ce labe ls , i n se r t s , overwraps, t ags and s t r ing . You may not think t h a t s t r i n g i s a hazard; but we've had some p r e t t y high counts on s t r i n g used on manufacturing meat, casing ends, e tc . We're a l so concerned with ingredients. We've es- tab l i shed standards f o r items l i k e mustard, ol ives , pimento, pickles , gelat in?, soy f lou r , binders, s a l t , sugar, dr ied milk, sauces, s ta rch and, of course, water. Pepper i s another one t h a t we ge t i n t o t rouble on qui te frequently. Microbiology. They've j u s t completed analysis of t h i r t y samples. On eleven samples they made a t o t a l count, and they averaged mi l l ion per gramwith a range of 8,300,000 t o 704,000,000 organisms per gram. t h a t gives you an example of t h e kind of counts you can run in to . always concerned with personnel. We've used p l a s t i c gloves qui te successfully. To extend storage l i f e , we've t e s t ed p l a s t i c aprons and we l i k e them p r e t t y well. We use germicidal soaps, of course, and we do a l o t of checking on the a i r movement through the plant . We check espec ia l ly f o r mold spores i n smoked meat areas. We have t r a in ing ses- sions s e t up f o r supervisory personnel. We put out reminder bu l l e t in s t o the various departments, espec ia l ly i n the springtime, because they ge t a l i t t l e care less about leaving the meat out i n warm areas. So, it i s necessary t o st imulate them i n the springtime. And we t r y t o make everybody conscious of t h e f a c t t h a t we must have low temperatures and we must have fast handling. I th ink t h i s supplements Eob's statements a b i t . I think, Tom, i f we have time f o r a question or two, w e ' l l do t h a t now.

Pa i l s , l i d s fo r

I ' v e clipped out an a r t i c l e i n the May issue of Applied

So, We're

DR. BLUMER: I bel ieve on the microphone s i tua t ion , we'd be b e t t e r of f t o cover each panel i s t a t t h i s time, and then have questions f romthe f loor . Our next pane l i s t i s Dr. R. B. Tompkin, Bruce Tompkin, chief microbiologist f o r Swift and Company. I met him f o r the f i r s t t i m e yesterday evening, and I said, lrBruce, you're not very old." said, "Well, I grew r e a l f a s t and got a l o t of breaks." D r . Tornpkin w i l l speak of t he second paper or Dr. Riemann's paper. Dr. Tompkin.

He So, Bruce,

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DR. TOMPKIN: Thank you, Tom. I have the make on D r . Riemann's paper. I th ink t h a t f o r lack emphasis of t he paper dea l t pr imari ly with avoiding He only b r i e f l y mentioned t h a t t he basic pr inc ip les microbial species. Perhaps it should be emphasized t e s t s can and should be made which w i l l predict the

following comments t o of time the overa l l public hea l th problems. could apply t o any fu r the r t h a t s imilar acceptable shelf l i f e

of new products and products produced under new processes or put up i n new packaging concepts. It i s not impossible f o r a new concept t o f a i l i n the l a t e developmental stages a f t e r un rea l i s t i c preliminary t e s t s . t h i s might occur when the normal b a c t e r i a l l e v e l of meat produced a t t he p lan t l e v e l might be higher than t h a t f o r meat produced under acceptional conditions i n the laboratory. A s a r e s u l t it lowers shelf l i f e of a product more than might be expected. This a l so t i e s i n with D r . Riemann's point t h a t inoculated packs must simulate the ac tua l processing condition, Icoculated -- pack work f o r food-poisoning organisms and s h e l f - l i f e t e s t s f o r normal spoilage organisms should be integrated with the developmental program f o r new products. done a s l a t e as possible i n the developmental program. w i l l be changes i n e i t h e r t he formulation of t he product or i n the packaging concept which could eventually r a i s e a b i g question mark on t h e t e s t s t h a t were developed up t o t h a t time. My next coment concerns the past more than the future . should review already ex is t ing products. past might not be acceptable..at present. Times change. For example, t he old process of producing head cheese by cooking the ingredients, f i l l i n g i n t o a pork stomach o r beef bung, and then giving a mild heat t o cook the casing has been shown t o be po ten t i a l ly hazardous from the standpoint of Salmonella in fec t ions , Now t h i s i s primarily j u s t a matter of s an i t a t ion i n the operation. segments of t he industry f o r producing cooked turkey r o l l s . Thus, t o me t h i s means t h a t we have t o look backward a s wel l a s forward i f we a re t o make the nost of our research e f fo r t s . One other point, while we must be forever conscious of t he hazard of botulism i n our canned foods, it should be pointed out t h a t one of t h e major problems facing the canning industry i s t h a t of highly hea t - res i s tan t thermophilic anaerobic spore formers. Many of these spore formers a re more hea t - res i s tan t than clostridium botulinum. And fo r t h i s reason alone the thermo-process f a r exceeds the minimum bo tu l ina l cook f o r a la rge number of food products. above approximately 3 a re of ten considered fo r closteridium botulinum; but I wonder j u s t how many products would survive on the shelves with such a process. And I r a i s e the question i s a pH of 6 so comlon.

Specif ical ly ,

I bel ieve t h i s bac te r io logica l work should be Invariably there

A s information becomes avai lable , we What had been accepted i n the

A s imi la r process i s current ly being used i n some

And pH's

Final ly , I ' d l i k e t o point out t h a t it vas apparent from Dr. Riemann's paper t h a t whenever we 8re i n doubt about t h e sa fe ty of a new product o r process, we should always conduct an inoculated-pack t e s t . Tom.

DR. BLUMER: Thank you, Bruce. Now very few people know the next pane l i s t , Nr. W. L. Sulzbacher, A. R. S., U.S.D.A. He's the chief a l so -- Chief of t he Meats Laboratory there , and B i l l has a unique pos i t ion -- He's a pa r t of the project of which Dr. Ayres spoke, So, I hope we can ge t him shut of f i n time. B i l l .

MR. SULZEACHER: Thank you, Tom. . . .It 's nice t o know t h a t I 'm not too wel l known, because I have some fea r s about t h a t . the chief .

He sa id I was We have one i r reverent employee whose name I won't t e l l you,

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but who c a l l s t h e "chief meathead." pa r t t o play i n t h e pro jec t t h a t D r . Ayres described, except t h a t we went t o him a few years ago. research on fungi and meat, and we knew tha t John had some experience a s a mycologist, and we asked him i f he'd be in te res ted i n working on t h i s kind of a project . He admitted t h a t he would be and so, t h a t ' s about my pa r t of it. The man who r e a l l y supervises it from our standpoint i n t h a t the supervision i s extremely meager i s John Allford who i s i n charge of our microbiology group whom I th ink you a l so know. But I was qui te pleased; I must say, by the way, t h a t D r . A p e s presented t h i s very complicated subject. whole s to ry e i the r , because t h e r e ' s a l o t t o some of the other chemical data t h a t i s a l so very in te res t ing . f o r t h i s , but we j u s t d idn ' t have enough time. I would l i k e t o emphasize two things t h a t John covered i n h i s paper. One i s the ra ther i n t e re s t ing a c t i v i t y of microorganisms i n changing the cha rac t e r i s t i c s of fat. And these a re things t h a t we are j u s t beginning t o become aware of. a fellow i n our laboratory who's working, not qui te along these l i nes , but he ' s come up with information t h a t ' s complementary t o what John's people have found out. This chap t h a t I ' m r e f e r r ing t o i s Dr. Smith i n our group, and he has shown recent ly t h a t various microorganisms change the carbonyls found i n oxidized fa t i n various ways. I n some groups, f o r instance, w e ' l l knock out a l l t he saturated aldehydes. I n other organ- i s m s w e ' l l knock out t h e two-four dieneals. I n c ther organisms w e ' l l knock out 2-enols. And then i n some organisms w e ' l l knock out a l l the carbonyls. But regardless of these things which have an i n t e r e s t t o bac ter io logis t s , there remains the c l ea r implication t h a t microorganisms growing on food products t h a t a re kept f o r long periods of time such as these sausages, and hams, w i l l a l t e r t he kinds of f lavors which you would get from t h e oxidation t h a t ord inar i ly would occur i n t h i s period of time. Some years ago a t Be l t sv i l l e when we were experimenting with cured hams, we observed t h a t i f we aged these hams at f o r t y degrees Fahrenheit, they were qui te unpalatable and had a very, very, poor s o r t of a f lavor . them a t seventy degrees, t he f lavor was highly acceptable. t h a t what's happened i s t h a t t he molds and possibly some other micro- organisms grown a t the higher temperature have a l t e r ed the kinds of f lavors t h a t a re produced by the oxidizing f a t .

(Laugh). I haven't had much of a

We were in te res ted i n someone doing some

And I can assure you t h a t he d idn ' t t e l l you t h e

We should have had the whole time

We have

But i f we aged It now appears

Another point t ha t I wanted t o make was t h a t t h i s s o r t of work t h a t JohnAyres has reported here points out a new area of research f o r some of t he r e s t of us t h a t might be in te res ted i n new kinds of products. You know t h a t the meat curer today wants t o ge t high f lavor and maybe unusual flavors; but he has t o do it i n a minimum period of time. Not very many meat processors a re so geared t h a t they can spend months and even years i n producing a, product fo r sale . Now I know t h a t , Tom, the re a re those fellows down i n North Carolina and i n other places. of t he country i s not t h a t l e i s u r e l y anymore, and we want t o ge t these kinds of products i n weeks r a the r than months.

But most

DR. BLUMER: You're misinformed. (Laugh).

MR. SULZBACKER: So, I bel ieve t h a t more invest igat ions of the fungal enzymes, and how they can be used i n meat processing, may br ing us a whole new family of meat products and ce r t a in ly new f lavors t h a t can be

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incorporated in to rreats. This i s j u s t a s o r t of challenging idea t h a t occurs t o me, and I thought maybe some of you might want t o do a l i t t l e work on microbialbiochemistry along with meats and might l i k e t o pick t h i s up. from Virginia. A few years ago I was i n h i s c e l l a r fo r some reason or another. And there hanging i n h i s coalbin were some ra ther odd-looking things. I a.sked him a question about t h a t . He t o l d me t h a t those were four hams produced on h i s place down i n Virginia, and he w a s saving them f o r t h e i r f i f t i e t h wedding anniversary.

I ' d j u s t l i k e t o say one more thing. I have a f r iend who's

DR. BLUMER: No comment. (Laugh). Now we would l i k e t o have audience pa r t i c ipa t ion and questions.

IbTR. BEERY: (Penn. S ta te ) . This i s directed t o Dr. Ayres. Do the microbial changes take place i n the center of t h e hams a s wel l a s on t h e outside?

DR. AYRES: No, +re found very l i t t l e microbial change i n the center, except where you had bad cracks i n the ham. Then you would have migration of t he molds t o the center. We've shown no associat ion between the yeast and the f lavor of t he aged ham.

&E. SWIFT: What i s water a c t i v i t y ? You were t a lk ing about some growth was d i f f e ren t than another on account of t he water ac t iv i ty .

DR. AYRES: A s the ham ge ts older, I ' d say it loses twenty- f i v e t o t h i r t y per cent of i t s o r ig ina l weight. And because you have a higher s a l t content, you have l e s s water per gram of ham. You have necessar i ly more s a l t y mater ia l and less water, and where you encounter some of these molds such as Aspergillus Ruber, t h i s organism w i l l grow down to a water a c t i v i t y of 0.85. Does t h i s hel?? You contrast t h i s with what you f ind with Staphalococcus aureus. i f you take Salmonella. it won't grow below 0.95. And i f you take Pseudorronas, they won't grow below 0.89. Therefore, you have t o have a wet surface f o r Pen ic i l l i a t o produce colonies and, therefore , slime. And i f you have a s l i g h t l y sa l ted product, you won't have much trouble with Salmonella. t rouble with Staph.

It won't grow below 0.9. And

If you have a heavily sa l t ed product, you won't have too much But you w i l l have t o leach the s a l t back out t o ea t it.

DR. HEIJRICKSON: I n rela.tion t o t h e top ic of control of microbial f l o r a i n raw material , when a company poceeds t o e s t ab l i sh a new plant , how do you proceed t o survey the micro-flora t h a t would be present i n the a i r i n t h a t area t o determine the extent of contamination t h a t you might expect?

bR. SULZEACKER: I th ink t h i s i s going t o depend upon, a t l e a s t t o some extent , what products a re involved, and, secondly, i f you want t o get a rough idea a s t o t h e extent of a i rborn contamination, you could use t h e exposure-plate techcique. go on t o some of these forced-air or sli t-samplers and ac tua l ly def in i - t i v e l y determine the number of bac te r ia or spores t h a t a re i n a given a i r volume. I th ink t h a t , generally speaking, f o r most sausage operations and things of t h i s nature, a i r contamination i s not a major consideration i n reference t o san i ta t ion of t he l i n e i t s e l f . Although a t times it can be a problem with spore -formers.

If you wanted t o become more refined, you could

Have I answered your question?

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DR. HENRICKSON: Yes, I was j u s t wondering. Do you take the analyses of various s t r a t a of the a i r ?

MR. SULZBACHER: Generally, what you're concerned w i t h i s the surface area t h a t you're working with--the surface area t h a t the product i s going through. And you can make your exposure p la tes fo r your a i r samplings a t t ha t level . I f e e l t h a t w i t h forced a i r there i s a f i l t e r associated with your a i r system. Generally, t h i s i s a good place t o sample, and t h i s w i l l d i c t a t e the necessity f o r change or frequency of change of t he f i l t e r . I th ink the milk people a re extremely concerned with air-born contamination and the dr ied milk operations a re now. contamination and environmental contamination i n general, and air- f i l t r a t i o n seems t o be a cazdinal consideration i n t h i s type of plant .

They are becoming acutely aware of a i r -born

UNIDEhTIFIED VOICE: One more comment -- i f you're ta lk ing about a smoked-meat plant , you've got t o be concerned about mold- spore contamination. This i s the r e a l problem. I th ink D r . Deibel answered haw t o determine the numbers, but i f you're ta lk ing about smoked meat, mold spores w i l l be your pr inc ipa l problem.

UNIDENTIFIED VOICE: Bob has broken down the problem in to The one i s the milk-drying p lan t , where you're ac tua l ly two types.

us ing a large volume of a i r t o dry the product. plant t h i s i s done i n c e r t a i n instances, but I f e e l , personally, t h a t the problem i n the meat-packing industry l i e s more w i t h what i s i n a person's hands and what i s on the equipment used and the condition of the raw mater ia l i s question. These a re the areas i n which we should put the grea tes t emphasis f o r t h e majority of t h e products and processes i n the meat plants .

I n the meat-packing

MR. HOKE: I ' d l i k e t o d i r ec t a question t o D r . Brown. You mentioned t h a t on your imported meats or the purchased meats t h a t you br ing i n t o your p lan t , t h a t you sample these. these a re carcasses. What pa r t of t he carcass do you take your sample from?

I assume t h a t most of

DR. BROWN: Well actual ly , OUT biggest percentage of products a re not carcasses; t hey ' r e individual cuts. A l o t of them are r a w mater ia ls f o r sausage -- i r r egu la r trimmings and a l l kinds of beef. Pork materials a r e used for sausage, We a l so buy primal cuts . We've developed various techniques for sampling, depending upon the product. We've even devised some techniques f o r sampling frozen products and I would be glad t o discuss w i t h you a f t e r the meeting. your product before you define your sampling technique.

We use a l o t of hams.

Bu t you almost have t o define

DR. ALSMEYER: I ' d l i k e t o d i r ec t a question t o Dr. Brown. How do you bes t reduce the microbial contamination i n packaging mater ia ls and black pepper. Do you use dry heat or how do you do t h i s ?

I th ink you mentioned ra ther high counts.

DR. BROWN: Well, we generally t r y t o leave t h i s up t o the supplier. I n t h e case of black pepper, we buy s t e r i l i z e d spices t h a t

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have e i t h e r been through ethylene or propylene oxide s t e r i l i za t ion . And we have a p r e t t y good supply of' these, materials you've got t o work with the suppliers. We don ' t run i n t o too much problem on p l a s t i c films. s t r ings and s tockinet tes and with t h i s kind of product occasionally.

I n t h e case of packaging

We do run i n t o problems with

UNIDEhTIFIED VOICE: B i l l , can you specify t h a t these products can be s t e r i l i z e d ?

DR. BRGWN: Yes. The black pepper t h a t we used i n a l o t of contract.work. It s t a t e s t h a t we w i l l use spices of good bac ter io logica l qual i ty , and i n case we get i n t o l imi ta t ions on what we can use, we buy s t e r i l i z e d spices. but you can see from these counts t h a t I quoted e a r l i e r , t h a t black pepper can contribute t o t h e t o t a l microorganisms i n your products.

They cost a l i t t l e more,

MR. BRATZLER: Dr. Ayres, i n t he heal th aspects, a consumer c a l l s i n and says t h a t there i s mold on t h i s product ( w e ' l l say dr ied sausage or even commercial hams of today) and she ' s worried whether i t ' s f i t t o ea t . What do you from your experience t e l l t h e consumer? What should she do with the product?

DR. AYRES: Well, I used t o speak ra ther g l i b l y about t h i s . anything, because (laugh) t h i s mycotoxin problem has everyone worried. What i s the government spending on the program now? year on t h e Nycotoxin Program?

I put my tongue i n my cheek now, and I ' d t r y t o avoid saying

This i s , per

UNIDEJ!iTIFIED VOICE: Nearly two mil l ion.

DR. AYRES: I th ink many people are worried about what food products may have mycotoxins, and I would say t o be safe, don ' t touch it. But we know tha t most of t h i s r e f e r s t o symptoms they have found under ra ther strange exot ic conditions. It does not r e f e r t o a r e a l food product. molds a re e n t i r e l y harmless, and I ce r t a in ly hope so as f a r as blue cheese i s concerned.

The probabi l i ty i s t h a t most of t he

DR. BLWER: I have one question, I would l i k e t o d i r ec t t h i s question t o D r . Riemann. What percentage of our color problems i s due t o microorganisms i n our packaged meats?

DR. RIEmNN: Well, I don ' t think I 'm the r igh t one t o answer t h i s question. It probably ought t o be directed t o D r . Tompkin. Are you ta lk ing about f resh meat or processed meat? I can give you any f igures or any numbers. Maybe D r . Brown or Dr. Tompkin or Dr. Sulzbacher can give you a b e t t e r answer.

I don ' t think

UNIDENTIFIED VOICE: Your question, I ' d l i k e t o repeat it t o make sure it comes out r igh t . VJhat percentage of t h e problems of color a re associated with b a c t e r i a l growth? a l l I can say i s t h a t frequently, I don't know what percentage t h i s i s , wherever we do have off-color, we have a high b a c t e r i a l count. I t ' s more o r l e s s d i r e c t l y associated. They're hand i n hand. Whether or not t he bac ter ia cause the color changes, per se, some work needs t o be done on t h a t .

Is t h a t r i gh t? Well,

175.

UNIDENTIFIED VOICE: I'll make one comment here. I think you have t o divide your question i n t o cured color and fresh color. If you're talking about the cured color of a vacuum-packaged product, I would guess that your b a c t e r i a l growth has very l i t t l e e f f ec t on whether or not t h i s vacuum-packed product holds i t s color i n the r e t a i l display case. On the other hand I would have t o agree t h a t on fresh meat your bac te r i a l growth w i l l have a marked e f f ec t on the colored product.

DR. BLUMER: I wish t o thank the speakers and the panel f o r appearing on our program. If you ' l l t u r n t o page th i r teen , you ' l l note the Microbiological Committee, who helped formulate the program, and R. B. Sleeth i s coordinator of t h i s par t icu lar section. Lunch i s i n the Omaha Room here a t the Center, If there a re no announcements, we're adjourned u n t i l a f t e r lunch.

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