Formula, Dough Mixing Methods, and Keeping Qualities of a Sweet Yeast

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Formula, Dough Mixing Methods, and Keeping Qualities of a Sweet Yeast lPORLtULA, DOUGH MIXING METHODS, AND KEEPING Q,UALITIES OF A SWEET YEAST RO.LL MIX b7 BARBARA ANN ROBINS .A. THESIS submitted to OREGON STATE OOI.I.JnE tn partial tultillment or tbe requirements tor the degree or MASTER OF SCIENCE June 1954 qfri lrilrlr| if ,'|t& Redacted for Privacy !il(t)r filml'ra ,. In o Redacted.firilo for il;ilroPrivacy lrrFe tr rrstlgD Redactedt;rtt{lrl for ilrr Privacy rt tr Jo I Redacted. rilrf ,Ir for ilfiqO Privacy rt i-\; 'j: r.trt&trtr tsr l}oiai ro fumirrl rtiltil{fT The writer wishes to express her sincere apprecia­ tion to Dr~ Andrea 14acUcey tor the stimulating way in which she directed this study and tor the t~e and ettort given, beyond the call ot duty, in preparation ot this manuscript. Appreciation is expressed to the author's husband, Charles s. Bobins, tor the interest and oontidence he has shown in her work and tor the many ways in which he made 1t possible. Acknowledgment is gratefully made to Belen Charley, Grace Goertz. Alta Garrison, 14er1anne Strauss and Emogene Veal tor their assistance in evaluating the products. TABLE OJ' CONTENTS CHAPTER Page I IBTRODUCTION • • • • • • • • • • • • • • • 1 II REVIEW OP Ll'l'EBJ.TURE • • • • • • • • • • • 5 Yeast • • • • • • • • • • • • • • • • • 5 Controlling Dough DeTelopaent • • • • • ll By'drogen-Ion Oonoentration. • • • • • • 21 Colloidal Properties ot Doughs. • • • • 24 III EIPERDIENTAL PROCEDURE • " . • • • • • • • Zl Introduotion. • • • • • • • • • • • • • 31 Ingredients • • • • • • • • • • • • • • 34 :rorm.ulas. • • • • • • • • • • • • • • • 35 Mixing Methods. • • • • • • • • • • • • 36 Handling Kethods Atter Mixing • • • • • 38 Equipment tor Preparing Rolls • • • • • 40 Equipaent tor Measurements. • • • • • • 40 Measurements to Determine Mix Properties • • • • • • • • • • • • • 41 Measurements to Determine Dough Properties • .. • • • • • • • • • • • 42 Measurements to Determine Roll Properties • • • • • • • • • • • • • 45 IV RESULTS AND DISCUSSION • • • • • • • • • • Properties ot the Mixes • • • • • • • • 47 Doughs. • • • • • • • • • • • • • • • • 57 Bolla • • • • • • • • • • • • • • • • • 66 v • • • • • • • '/7 BIBLIOGRAPHY. • • • • • • • • • • • • • • • • • • • • eo APPENDIX ••• • • • • • • • • • • • • • • • • • • • • 84 LIST or TABLES TABLE Page 1 Methods tor Mixing Doughs • • • • • • • • • 37 2 Meaaureaents ot Mixogram Patterns in Units ot 1/~0 InOh •••••• . • • • • 49 (Appendix) I ATerage Carbon Dioxide Production, pH Values and Ratio ot Active to InactiTe Yeast Cells tor Each Mix at o, 5, and 10 eeka Storage • • • • • • • • • • • • 85 II ATerage Proofing T~ea 8Dd Fermentation Timea tor Doughs at O, 5, and 10 eeka Storage. • • • • • • • • • • • • • • • • 86 III Ezpanaib1lit7 of Doughs as Indicated by Volume Attained and Ttme Required tor Maxlmum Expansion. • • • • • • • • • • • 87 IV Average pH Values at iach Storage Period ot Standard and Mix Dougha When Firat Prepared, After lermentation, and After Proot1na • • • • • • • • • • • • • 88 v Analysis ot Variance ot Scores tor Roll Palatability •••••••••••• • • 89 VI ATer ge Soores tor Rolle ade From Rolls Made by Three Methods From Freshly Prepared Mix • • • • • • • • • • • • • • 90 VII ATerage Soores tor Rolls Jlade by- Three Methods Jrom Mixes Stored 5 eeka. • • • 91 VIII Average Scores tor Rolla Made by Three Methods From ixes Stored 10 eeks • • • 92 IX Analya1s ot Variance ot Roll Cross­ Section Areas. • • • • • • •••• • • • 93 X ATerage Cross-Section Areas ot Standard Rolls and Rolls Made by Three Methods From Mixes Stored 0, 5, and 10 Weeks •• LIST OJ' J'IGURES liGURE Page 1 Looat1on ot M1::mgr8lll Meaaurements • • • • • 48 2 Relationship ot Aot1ve-InaotiYe Yeast Oella to Extent ot Break in Mi::mgrem Patterns During Storage. • • • • • • • • 55 Relationship ot the Total Oarbon Dioxide Production to the Total J'er.mentation Time ot Eaoh Mix • • • • • • • • • • • • 55 Relationship or Total Carbon Dioxide Production to Dough Expansion at Eaoh Storage Period • • • • • • • • • • • • • &l Relationship During St.orage ot Dough Expansion to Kixogrea Measurements; . Height to Peak and Length to Peak. • • • 61 6 Relationship of Roll Cross-section Area to Mixogram Extent of Break tor Mix II at Eaoh Storage Period. • • • • • • • • • • 63 7 Relationship of Dough Expansion to Total ~ermentation Ttme at Eaoh Storage Period 63 e Relationship ot Final Dough pH to Dough Expansion tor Eaoh Mix • • • • • • • • • 65 9 Relationahip ot J'inal Dough pH to Total J'ermentat1on T~e at Eaoh Storage Period 65 10 Relationabip ot Cross-Seotion Area to Dough Expansion tor Eaoh Klx • • • • • • 11 Belat1onah1p ot Cross•Seotion Area to Total J'ermentat1on Ttme ot Bolls Prepared by lour Mixing Methods :rrom Jlixes I end II . • • . • • • • • • . • • • 12 Relationship ot Total Crumb Springiness Soorea to Total Fermentation Time of Rolla Prepared by Four Dough Mixing Methods. • • • • • • • • • • • • • • • • 71 LIST OF J'IGURBS (Coo.t.) J'IGURB Page 13 Belat.ionshlp ot Total Crumb Oolor Sool"•• to Total Fermentation Time Gt Rolls PJ.'epared by Four Mixing Methods From. 141xe.s I end II • • • • • • • • • • • .. 71 14 Relationship or Total Odor Scores to 'rotal F rm.e.u ...e.tion Time of Rolla Prepared 'by re't.Ul' Kixlng Methods. • • • • '14 15 Relationship ot Total 7la•or Scores to Total J'erm.entati~ul Time ot Bolle Prepared by Four Mi•lns Methods From Mixes I and III. • • .. • • , • • • • • • 11 Belat1oneh1p ot Total Odor and Flavor soores to Final ;Dough pH at Baoh Storage Period • • .. .. • .. " , • • • • • 75 (Appendix) I Bttect ot Ditterent Yeasts on t.ftxosram. Patterns • • • • • • • • • • • • • • 95 I ,I . Etteot ot Freshly Prepared Mixes on Mtxogram ~att•rna. • • • ~ • • • • • • • 96 III Etteot ot Kixes on JUxogrem. Patterns After 10 Weeks ot Stol'"age. • • • • • • • 97 · IV External end Internal Appearance ot Standard and Mix Rolls Alter 10 Weeks Storage. • • • • • • • • • • • • • • • • 98 FORMULA, DOUGH MIXING METHODS , AND KEEPING UALITIES OF A SWEET YEAST ROLL MIX CHAPTER I INTRODUCTION A "mix" may be defined (16. p.l075) as an assemblage ot substances that are thoroughly diffused among one an­ other. The word "mix" when a pplied to a food product 1m­ plies an intimate blend ot ingredients or tood materials. The current popularity of tood ready..:mixes may be attributed largely to the convenience associated with their use. M8DY . Of the ingredients necessary tor prepar­ ing the desired tood product have been assembled, measured and combined in advance. Thus, the steps involved at the time of rood preparation e.re reduced in number. The chief' object of the present investigation was to develop a yeast ready-mix formula which the homemaker could prepare and store at home. and use as a convenient shortcut for the preparation of a variety of yeast­ leavened products. Previous to this investigation, no yeast ready-mix formula had been developed. The mix here­ in reported is the first to omit flour and include yeast as an essential ingredient. It retains the aspect ot con­ venience, at the same time eliminating several problems heretofore associated with the home preparation end stor­ ase ot mixes. 2 Ot the mixes whioh haTe been developed tor home prep­ aration, ell involTe the sitting together ot the dry in­ gredients which oonsiet ot tlour, baking powder, dried milk, salt and sugar. The shortening is then blended with these combined ingredients. A cumbersome aapeot in the preparation ot these mixes ia the handling ot large quan­ tities ot dry ingredients wh1oh must be aitted together several times. Another is blending the tat into auoh quantities of dry ingredients. A further problem 1a the storage ot the completed mix. Ita large bulk introduces the necessity of finding numerous suitable containers as well as shelt or refrigerator spaoe. In oontre.at to the problema inherent in the usual home-prepared mix, the yeast ready-mix tormula described in this paper 1a easy to prepare and store. The omission ot flour reduces the bulk, thus simplifying both the preparation and storage ot the mix. The formula includes shortening, sugar, aalt, powdered egg, powdered milk end active dry yeast. These ingredients are blended together to form e. oreamy, attractive mix or smell volume. Beoaus or their many adTante.ges, mixes have won a permanent plaoe in the baking industry. They make pos­ sible real savings in labor, storage space, and time. They reduce the possibility or error by limiting the num­ ber ot ingredients that must be soaled. They help to 3 insure the uniformity and high quality ot the finished product•. Laster {24, p.ll4) states that there have been sever­ al types ot yeast bread mixes available tor use in commer­ cial bakeries. The tirst ot these mixes was designed to produce a basic sweet-yeast dough trom which a variety ot goods were made. Certain disadvantages were tound to be associated with the basic dough. It was essentially a . compromise dough yielding several products ot acceptable quality. However, none ot these were ot optimum quality. Because ot this shortcoming ot baste doughs, mixes have been developed tor 1nd.1vidua.l yeast-leavened products suoh as doughnuts and cottee cake. By adding eggs or tlour to these mixes opt~um doughs were obtained tor still other specific products. For example, eggs added to the oottee cake mix gave an optim.um dough tor Danish pas­ try. The baker, theretore. used several mixes plus tlour and eggs in order to obtain optimum quality doughs tor all ot his products. Although the mix reported herein was developed pri­ marily .tor home preparation and use, 1ts possible
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