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The research of the brewer’s spent grain on the example of one small Estonian enterprise
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Toiduainete tehnoloogia õppekavalÕlleraba on peamine pruulimise jääkaine. Viimase aastakümne jooksul hakkati seda nimetama õllepruulimise väärtuslikuks kõrvalproduktiks, sest oma keemilise koostise poolest suudab õlleraba konkureerida mõne muu teraviljaga. Peamine valdkond, kus õlleraba kasutatakse, on loomakasvatus. Õlleraba on väärtuslik ja odav söödalisand. Tänu õlleraba sisaldusele söödas võtavad loomad kehakaalu kiiremini juurde, lehmade piimajõud kasvab, samuti paraneb ka liha kvaliteet. Viimasel ajal aga otsitakse võimalusi kasutada seda ka inimtoiduks. Hea keemilise koostise tõttu saab õlleraba kasutada jahutoodete, lihatoodete tootmiseks, rikastades seeläbi lõpptoote toiteväärtust. Käesoleva bakalaureusetöö ülesandeks oli kirjeldada lühidalt õlle tootmistehnoloogiat; uurida selle protsessi jooksul tekkiva õlleraba keemilist koostist; võrrelda õlleraba sarnaste toodetega, nagu nisujahu, oder ja granola ning kirjeldada ka õlleraba kasutusvõimalisi. Töö eesmärgiks oli uurida ühes Eesti väikeettevõttes tekkiva õlleraba keemiline koostis ning pakkuda välja, millised tegurid võivad mõjutada õlleraba koostisese näitajaid. Katsematerjalina kasutati ühe Eesti väikeettevõtte poolt saadud õlleraba. Sellest analüüsiti niiskusesildust (nii toor- kui ka kuivatutud õllerabas), valkude, rasva , süsivesikute ning mõnede mineraalainete sisaldust. Tulemused näitasid, et kuivatatud õlleraba niiskusesisaldus sõltub suurel määral kuivatusmeetodist. Keskmised õlleraba keemilised näitajad olid sarnased kirjanduses toodud andmetega. Õlleraba keemiline koostis sõltub konkreetse pruulikorra jaoks kasutatud linnaste vahekorrast. Süsivesikutesisaldus sõltub ka õlle valmistamise koostisosadest ja õlle tüübist. Katses leiti, et kõrgeim suhkrutesisaldus oli proovides, mis võeti pärast tumeda õlle valmistamist. Proovides, mille koostis sisaldas palju otra, valke oli rohkem kui teistes samasugustes proovides. Kõrgeim kiudainesisaldus oli õlleraba proovis, kus odrasisaldus oli 100%.Brewer’s spent grain is the main brewing waste. Over the last decade, it has been described as a valuable by-product of brewing, because it can compete with other cereals based on its chemical composition. The main area where brewer’s spent grain is used is in livestock farming. Brewer’s spent grain is a valuable and inexpensive feed additive. If brewer’s spent grain has been added to animal feed then the animals gain weight faster, produce more milk and also, the quality of their meat improves. Recently, research has sought ways related to using brewer’s spent grain on human food products. Due to its good chemical composition, it could be used for the production of flour products and meat products, thus enriching the nutritional value of the final product. This thesis aimed to briefly describe the technology of beer-brewing; to study the chemical composition of the brewer’s spent grain formed during this process; compare the brewer’s spent grain with similar products such as wheat flour, barley and granola and also describe the possible uses of the brewer’s spent grain. The aim of the thesis was to study the chemical composition of brewer’s spent grain in one of Estonia’s small companies and to suggest which factors may affect the composition of the brewer’s spent grain. The brewer’s spent grain from one Estonian small company was used as a test material. The author analysed its moisture content (both raw and dried), protein, fat, carbohydrates and some minerals. The results showed that the moisture content of the dried brewer’s spent grain depends to a large extent on the drying method. The average chemical parameters of the brewer’s spent grain were similar to the data reported in the literature. The chemical composition of the brewer’s spent grain depends on the proportion of malt used for the particular brewing procedure. The carbohydrate content also depends on the ingredients of the beer and the type of beer. The experiment found that the highest sugar content was in the samples taken after the dark beer was made. Samples with a high barley content contained more proteins than other similar samples. The brewer’s spent grain had the highest fibre content where the barley content was 100%
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Laktoosi klasterdumine ja kristalliseerumine: Puhta laktoosi lahuse ja ricotta juustu vadaku eksperimentaaluuring
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ScienceCrystallisation is the main process in lactose production technology. It consists of several steps including formation of primary clusters of molecules, nucleation, growth of nuclei, and further formation of crystals. The aim of the current research work was to improve our knowledge about nucleation process and subsequent growth of lactose primary clusters depending on the temperature and concentration of the solution. The dependence of the lactose crystal final size and shape on the solution pH level and concentration, crystallization temperature and cooling profile were also investigated. The novelty of the present work was in the application of particularly sensitive optical technique (Zetasizer Nano ZS) to measure lactose particle size. This technique enables to measure the size of the smallest lactose particle and trace the growth of primary clusters without altering the original conditions of the sample. Investigation of clustering and crystallisation, using new techniques, will provide answers to numerous questions related to crystallisation of lactose and other sugars, as well as crystallography in general. The second aspect was that ricotta cheese whey was used as a raw material to explore the influence of environmental conditions on crystal shape and size. This raw material is rarely used in lactose production, but recently, stricter environmental requirements have increased interest to it. In Estonia, ricotta cheese whey was studied for the first time. The investigation and use of less traditional source of lactose will have a positive impact on the environment and provide substantial valorisation of these dairy by-products, and thus, have an added value for dairy production in generalLaktoosi tootmise tehnoloogiline põhiprotsess on kristalliseerimine. See sisaldab molekulidest esmaste kogumite ehk klastrite moodustumist, kristallituumade teket, kristallituumade suurenemist ja neist kristallide kujunemist. Käesoleva teadustöö põhieesmärk oli saada uusi teadmisi laktoosi kristalliseerimise algfaasist – laktoosimolekulide võimest moodustada esmaseid klastreid (kristallide algeid) sõltuvalt temperatuurist ja kontsentratsioonist. Samuti uuriti, kuidas mõjutavad laktoosikristallide kasvu ja lõppkuju lahuse pH ning kontsentratsioon, kristalliseerimise temperatuur ja temperatuuri alandamise kiirus. Käesoleva töö uudsus seisneb selles, et esmaste klastrite uurimiseks kasutati ülitäpseid mõõtmisi võimaldavat aparatuuri (Zetasizer Nano ZS), mille tõttu sai määrata üksiku laktoosimolekuli suurust ja jälgida lahusesse sekkumata laktoosiosakeste liitumisprotsessi. Selle protsessi uurimine uue meetodiga annab vastuseid paljudele kristalliseerimisprotsessiga seotud küsimustele nii suhkrute kristalliseerimise kui ka üldiselt kristallograafia alal. Teine aspekt on see, et analüüsides, mille abil uuriti lahuse parameetrite mõju laktoosi kristallide lõppkujule, kasutati toormaterjalina ricotta juustu vadakut, mida seni on laktoosi tööstuslikuks tootmiseks kasutatud suhteliselt harva. Viimastel aastakümnetel on huvi selle tooraine vastu suurenenud. Eestis ei ole seni ricotta vadaku kasutamise problemaatikaga tegeldud. Selle ebatraditsioonilise toormaterjali uurimine ja kasutamine aitab täiuslikumalt väärindada piimandussektoris tekkivaid kõrvalsaadusi ja vähendada keskkonnakoormust
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The Filtration Capacity of Buckwheat Malt and the Yield of Wort
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Toiduainete tehnoloogia õppekavalÕlu on kääritatud alkohoolne jook, mida tarbitakse üle maailma. Traditsiooniliselt
valmistatakse õlut gluteeni sisaldavatest odralinnastest, mis ei sobi tsöliaakiat põdevatele
inimestele. Paraku on gluteenivabade toitude ja jookide valik piiratud. Tatar (Fagopyrum
Mill.) on gluteenivaba taimeperekond tatraliste sugukonnas, millest tehtud õlu sarnaneb
maitse, lõhna ja mõruduse poolest tavaõllele. Eestis toodavad gluteenivaba õlut vaid
mõned tööstused ja väikesed pruulikojad. 100%-list tatraõlut Eestis ei toodeta ja tatart
lisatakse enamasti maitselisandina. Antud magistritöö eesmärk oli uurida tatralinnastest
tehtud meski filtreerimisvõimet virde eraldamisel ja virde kadu, et välja selgitada, kas
tatart on optimaalne kasutada ainutoorainena, et toota gluteenivaba õlut. Selleks on
katsetatud erinevate odra- ja tatralinnaste koguste vahekordadega ning uuritud virde
saagist, et leida tatralinnase mõju virde omadustele. Toorainena olid kasutusel
odralinnased „IREKS Pale Ale“ ning tatralinnased „Château Buckwheat“, lisanditeks
maisihelbed, tatrakestad ja ensüümipreparaat Ceremix® Flex. Virdest määrati
suhkrusisaldus, pH, erikaal, värvus EBC skaalal, erinevate süsivesikute sisaldus ja
viskoossus. Rabast määrati niiskus- ja süsivesikute sisaldus. Samuti mõõdeti virde saagist
liitrites. Tatralinnastega meskitud virde pH oli püsivalt üsna kõrge: leiti, et koguvirde pH
(lisatud veega) on vahemikus 6,26-6,53, ja ilma lisatud veeta 6,16-6,45. Tatralinnaste
osakaalu suurendamine tõstab virde pH-d, mis viitab nõrgale ensüümide toimele, selle
vastu aitab mingil määral ensüümide lisamine, mis alandab koguvirde pH-d. Tatralinnase
osakaalu tõstmine vähendas statistiliselt algvirde ja koguvirde suhkrusisaldust (r = -0,99,
p = 0,002 ja r = -0,91, p = 0,034). 50, 75 ja 100%-lise tatravirde puhul suurendavad
lisandid nagu maisihelbed ja ensüüm suhkrusisaldust. Tatrakestade kasutamine ei
avaldanud märkimisväärset mõju. Kõige väiksem kaoprotsent saadi kasutades 50%
tatralinnaseid ja 50% odralinnaseid, millesse oli lisatud ensüümipreparaati (8,6%).
Üleüldine kaoprotsent kõikides katsetes jäi 9-24% vahele. Tatralinnaste osakaalul ja kao
suurenemisel on tugev positiivne seos: r = 0,93, p < 0,05. Kadude vähenemisele aitab
kaasa nii maisihelveste kui ka ensüümi lisamine, kusjuures on ensüümi lisamisel 100%-
lise tatravirde kadu vaid ~17%. Maltoosisisaldus rabas vähenes tatralinnase suurema osakaaluga (r = -0,96, p < 0,05), kusjuures 100%-lise tatravirde puhul puudus maltoos
täielikult. Maltoosisisalduse parandamiseks kasutati ensüümipreparaati, mis tõstis
maltoosisisalduse 9,43%-ni. Tulemustest selgus, et gluteenivaba 100%-list tatraõlut on
võimalik pruulida ainult sel juhul, kui meskimisel kasutada ensüümipreparaati. 75%-list
tatraõlut saab pruulida ilma ensüümita, kuid esinevad maitse-, lõhna- ja viskoossusevead.
Virde omadused sõltuvad suuresti meskimisparameetritest, seega oleks tatralinnaste
filtreerimisvõime ja virde saagise täpsemaks hindamiseks tarvis läbi viia veel täiendavaid
uurimusi, kasutades kirjanduses leiduvaid optimaalsemaid meskimisparameetreid, mis
võiksid suurendada virde suhkrusisaldust ja saagist.Beer is a fermented alcoholic beverage that is consumed around the world. It is traditionally
brewed from gluten-rich barley malt, which is not suitable for people with coeliac disease.
Unfortunately, the variety of gluten-free foods and beverages is limited. Buckwheat
(Fagopyrum Mill.) is a gluten-free plant in the Polygonaceae family, the beer of which is
similar in taste, aroma and bitterness to ordinary beer made from barley. Only a few industries
and small breweries produce gluten-free beer in Estonia. Beer made only from buckwheat is
not produced in Estonia, and when it is buckwheat is usually added as an adjunct. The aim of
this master’s thesis was to study the filtration capacity of buckwheat mash during the
separation of wort from brewers’ spent grain (BSG) and the loss of wort, to find out whether
buckwheat can be used optimally as a sole raw material to produce gluten-free beer. To this
end, different ratios of barley and buckwheat malt were used, and the yield of wort was
examined, to characterise the effect of buckwheat on the quality of wort. The raw materials
used were barley malt “IREKS Pale Ale” and buckwheat malt “Château Buckwheat”, with
the addition of cornflakes, buckwheat husks and Ceremix® Flex enzyme. The sugar content,
pH, specific gravity, colour in EBC units, content of carbohydrates and viscosity were
measured from wort. Moisture content and the content of carbohydrates were measured from
BSG. The yield of wort was measured in litres. The pH of buckwheat wort was consistently
quite high: the pH of wort (with added water during filtration) was found to be in the range
of 6.26-6.53, and without added water 6.16-6.45. Increasing the proportion of buckwheat
malt raised the pH of the wort, which indicates little enzymatic activity, while the addition of
enzymes helped to some extent, and lowered the pH of the wort. Increasing the proportion of
buckwheat malt statistically reduced the sugar content of the initial and total wort (r = -0.99,
p = 0.002 and r = -0.91, p = 0.034). For mash with 50, 75 and 100% buckwheat malt, additives
such as cornflakes and enzymes increased the sugar content of wort. The use of buckwheat
husks did not have a significant effect. The highest yield (91,4%) was obtained using 50%
buckwheat malt and 50% barley malt with added enzymes. The overall loss rate in all
experiments ranged from 9% to 24%. There was a statistically strong relationship between
the proportion of buckwheat malt and the increase of losses: r = 0.93, p < 0.05. The addition of both cornflakes and enzymes contributed to the reduction of losses, whereas the addition
of enzymes resulted in a loss of only ~17% of wort made solely from buckwheat. The maltose
content in BSG decreased with a higher proportion of buckwheat malt (r = -0.96, p < 0.05),
whereas maltose was completely absent in the case of 100% buckwheat BSG. For this, an
enzyme was used to improve the maltose content, which increased it to 9.43%. The results
showed that gluten-free beer made solely from buckwheat malt can only be brewed if an
enzyme preparation is used in the brewing process. Beer made with 75% of buckwheat malt
can be brewed without added enzymes, but there are defects of taste, smell and viscosity. The
properties of the wort depend largely on the parameters of mashing, so further studies would
be needed to better assess the filtration capacity of buckwheat mash and the yield of wort,
using more optimal mashing techniques, as proposed in the literature
Determination of fermentation-acidification parameters in kvass
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Toiduainete tehnoloogia õppekavalKali on enamasti pärmi toimel kääritatud jook, kuid varasemalt kasutati protsessis ka
piimhappebaktereid (LAB). Käesoleva töö esmärk on selgitada välja, kuidas
piimhappebakterid mõjutavad nii üksi kui ka koos pärmiga kaljavirde käärimist 16 tunni
käärimise jooksul. Töös tehti selgeks üldine kalja tootmistehnoloogia ning võimalused
tootmiseks. Vaadeldi teiste autorite tulemusi seoses kalja või pärmide/piimhappebakterite
uurimisega. Valiti LAB-kultuurid: Nordwise Lactobacillus plantarum TAK69, Wildbrew
Sour Pitch L. plantarum, Wildbrew Helveticus Pitch L. helveticus. Töös leiti, et
happeliseim oli Sour Pitch, järgnes Helveticus Pitch ning viimaseks Nordwise. Koos
pärmiga käärimisel oli suurim happesus (g/L sidrunhapet) enamasti 80/20 vahekorras
LAB-pärm käärimisega ning enim sidrunhapet leidus Sour Pitchiga (2,84 g/L), veidi
vähem Helveticus Pitch-iga (2,24 g/L) ning Nordwise puhul oli suurim happesus 50/50
puhul, 80/20 happesus sel puhul 1,45 g/L. 50/50 vahekorraga oli madalaim suhkrusisaldus,
kuid võrreldes 80/20 vahekorraga Sour Pitch ja Helveticus Pitch puhul veidi kõrgem pH
ja madalam sidrunhappe sisaldus: Sour Pitch 2,58 g/L; Helveticus Pitch 2,09 g/L;
Nordwise 1,62 g/L. 100% LAB-iga käärimisel suhkrusisalduse näitaja ei langenud, pH oli
kõrgeim ja sidrunhappe sisaldus madalaim, välja arvatud Sour Pitchiga, kus pH oli madalaim (3,57), kuid sidrunhappe sisaldus samuti madalaim (2,34 g/L). Poekalja pH-ga
(3,45) võrreldes oli saadud kaljade pH kõrgem ning sidrunhappe sisaldus (poekaljal 1,15
g/L) samuti kõrgem. Tulemustest leidus, et kalja füüsikalis-keemilised näitajad olenevad
enim kasutatavast LAB-kultuurist, väiksemal määral LAB-pärm vahekorrast juhul kui
kasutati nii pärmi kui LAB-i. Ainult LAB-i kasutades oli käärimise kiirus väga aeglane
ning näitajad muutusid väiksemal määral, välja arvatud Sour Pitch. Edasised uuringud ja
katsed piimhappebakteritega võimaldaksid leida optimaalsed LAB-kultuurid ning
meetodid hapendatud kalja tootmiseks.Kvass is a drink usually fermented with yeast but in the past lactic acid bacteria (LAB)
have also been used. The purpose of this research is to monitor how LAB affect the
fermentation process of kvass with or without the presence of yeast during 16 hours of
fermentation. Technology and methods for kvass production were studied, along with
prior research of kvass production and use of yeasts/LAB from authors. Three LABcultures were chosen: Nordwise Lactobacillus plantarum TAK69, Wildbrew Sour Pitch
L. plantarum and Wildbrew Helveticus Pitch L. helveticus. In the study, Sour Pitch made
for the most acidic kvass, followed by Helveticus Pitch and Nordwise was the least acidic.
With the addition of yeast in fermentation, the greatest acidity (g/L citric acid) was found
mostly with 80/20 proportion of LAB/yeast and the most citric acid was found with Sour
Pitch (2,84 g/L), followed by Helveticus Pitch (2,24 g/L), for Nordwise, 50/50 had the
highest acidity, 80/20 citric acid value was 1,45 g/L. The 50/50 proportion had the lowest
sugar content but compared to 80/20, in the case of Sour Pitch and Helveticus Pitch, the
pH was higher and acidity lower: Sour Pitch 2,58 g/L; Helveticus Pitch 2,09 g/L;
Nordwise 1,62 g/L. In the case of 100% LAB fermentation, sugar content did not decrease,
pH was the highest and acidity the lowest, except for Sour Pitch, which had the lowest pH
(3,57) but also the lowest citric acid content (2,34 g/L). Compared to the pH of commercial
kvass (3,45), kvass made in this research hag higher pH and also higher citric acid content (for commercial kvass 1,15 g/L). The results show, that physical-chemical indicators of
kvass are most affected by the choice of LAB-cultures, less so by LAB-yeast proportions
if yeast is used. When using only LAB, the speed of fermentation was slow and the
indicators varied less, except for Sour Pitch. Further research and experiments with lactic
acid bacteria could yield optimal LAB-cultures to use in production of acidified kvass
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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