Sous vide meetodi rakendamine veiseliha töötlemisel
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Kuupäev
2018
Kättesaadavus
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Magistritöös uuriti erinevatel temperatuuridel (55, 60, 65 ja 70 ℃) ja aegadel (4, 5, 6, 24,
48 tundi) töödeldud veiserümba välisfilee füüsikalis-keemilisi muutuseid.
Töö eesmärgiks oli uurida eelnevalt mainitud aegadel ja temperatuuridel tekkinud
muutuseid liha omadustes ja lisaks uuriti, kas liha eelnev pruunistamine toob välja olulisi
muutuseid liha omadustes.
Eksperimentaalses osas viidi läbi veiserümba välisfilee kuumtöötlemine sous vide
meetodil eelnevalt mainitud temperatuuride ja aegade kombinatsioonidel, millest sooritati
kolm korduskatset. Töötlemata lihast mõõdeti pH-väärtus, määrati värv ja
veesiduvusvõime. Kuumtöötlusel jälgiti loggeritega lihas toimuvaid temperatuuri
muutuseid. Töödeldud lihast arvutati küpsetuskadu, määrati värvus, lõiketugevus,
keemiline koostis NIR-analüüsiga ja sooritati sensoorne hindamine. Tulemustest selgus,
et liha eelnev pruunistamine tulemustes suurt muutust ei toonud. Täheldati küpsetuskao
vähenemist vaid 60 ℃ juures 4, 5 ja 6 tundi töödeldud lihadel, kus kahel pikemal
töötlusajal küpsetuskadude vahe kahanes. Oodatust erinevad tulemused saadi
lõiketugevuse osas, kus kirjanduses on toodud välja, et pikenenud küpsetusaeg peaks
märgatavalt liha pehmust suurendama. On leitud, et 24 tundi 50-60 ℃ töödeldud veiseliha
tulemused olid 26-72% pehmemad, kui neid võrreldi näiteks ühe tunni jooksul töödeldud
lihaga. Vastupidiselt käesolevas lõputöös läbiviidud katsetes kahel pikemal ajal (24 ja 48
tundi) töödeldud lihade pehmused oluliselt ei erinenud. Lühematest töötlusaegadest
pehmemad tulemused saadi vaid 70 ℃ töödeldud lihadest. Liha värvus muutus võrreldes
toore lihaga heledamaks. Sealjuures liha punasuse väärtus võrreldes toore lihaga oli
3
suurem 55 ℃ töödeldud lihal. Üle 60 ℃ liha punasus vähenes, kuna sel temperatuuril
toimub müoglobiini denatureerumine.
Sensoorses hindamises, kus osales 24 inimest, hindasid töödeldud lihade välimust, lõhna,
maitset, õrnust, mahlasust ja kummisust. Kahel madalamal temperatuuril ja ajal töödeldud
lihad on punasemad ja mida kõrgemaks tõusis töötlustemperatuur, seda pruunimaks liha
muutus. Lõhna ja maitset hinnati madalamatel temperatuuridel vere ja/või metalli ning
maksa maitset meenutavaks. Töötlusaja pikenedes leiti sarnasusi pigem veise ja keeduliha
lõhna ja maitsega. 55 ℃ ja 60 ℃ töödeldud lihad olid degustaatorite jaoks pehmed ja väga
pehmed, kuid kahel kõrgemal temperatuuril hinnati õrnust pigem vintskeks. Sarnased
muutused olid ka mahlasuse ja kummisuse hindamisel.
Täiendavalt tuleks veel läbi viia korduskatseid leidmaks ajast ja temperatuurist sõltuvaid
muutuste trende.
The aim of this master’s thesis was to study beef sirloin physical-chemical properties based on different temperatures (55, 60, 65 and 70 ℃) and times (4, 5, 6, 24, 48 hours). In addition, to determine if meat pre-searing would bring out any important changes in meat properties. In experimental part of the thesis, the beef sirloin was sous vide cooked at predefined temperature and time combinations three times per combination. pH-value, colour and water-holding capacity were measured from raw material. Sous vide cooked meat temperature changes were tracked with data loggers. Cooking loss, colour, shear-force and chemical composition were measured from thermally treated meat. Also sensory evaluation was carried out. Results showed that pre-searing meat did not have any affect on it’s physical-chemical properties. Reduction in cooking loss was noted only at 60 ℃ temperature, at 4, 5 and 6 hours cooking time, where at two longest cooking times the difference of cooking loss decreased between pre-seared and not seared meats. The results of shear-force differed from the ones expected. In articles it was brought out that longer treatment time should noticeably increase tenderness of meat. It was found that cooking for 24 hours at 50-60 ℃ increased meat tenderness by 26-72%, in comparison with one hour cooking time. Contrary to this, the result found in this study showed that longer treatment (24 and 48 hours) time did not bring out significantly higher tenderness. Out of the shorter cooking times more tender results were achieved at 70 ℃. Meat colour turned lighter compared to raw meat. Thereby, meat redness in comparison to raw meat was 5 highest at 55 ℃. Over 60 ℃ treated meat redness decreased because at this temperature myofibrillar proteins start denaturating. 24 people participated in the sensory evaluation, where they assessed sous vide cooked meat appearance, smell, taste, tenderness, moisture and rubberiness. At two lowest treating temperatures and times meats were more red and the higher the temperature rised the more brown meats became. Smell and taste were evaluated at lower temperatures resembled blood/metal and liver. At longer treatments that property changed to beef and boiled meat. 55 and 60 ℃ treated meats tenderness was rated tender and very tender, but at two higher temperatures tenderness was judged tough. Same trends were observed for moisture and rubberiness evaluation. Further research should be conducted to find time and temperature related property trends.
The aim of this master’s thesis was to study beef sirloin physical-chemical properties based on different temperatures (55, 60, 65 and 70 ℃) and times (4, 5, 6, 24, 48 hours). In addition, to determine if meat pre-searing would bring out any important changes in meat properties. In experimental part of the thesis, the beef sirloin was sous vide cooked at predefined temperature and time combinations three times per combination. pH-value, colour and water-holding capacity were measured from raw material. Sous vide cooked meat temperature changes were tracked with data loggers. Cooking loss, colour, shear-force and chemical composition were measured from thermally treated meat. Also sensory evaluation was carried out. Results showed that pre-searing meat did not have any affect on it’s physical-chemical properties. Reduction in cooking loss was noted only at 60 ℃ temperature, at 4, 5 and 6 hours cooking time, where at two longest cooking times the difference of cooking loss decreased between pre-seared and not seared meats. The results of shear-force differed from the ones expected. In articles it was brought out that longer treatment time should noticeably increase tenderness of meat. It was found that cooking for 24 hours at 50-60 ℃ increased meat tenderness by 26-72%, in comparison with one hour cooking time. Contrary to this, the result found in this study showed that longer treatment (24 and 48 hours) time did not bring out significantly higher tenderness. Out of the shorter cooking times more tender results were achieved at 70 ℃. Meat colour turned lighter compared to raw meat. Thereby, meat redness in comparison to raw meat was 5 highest at 55 ℃. Over 60 ℃ treated meat redness decreased because at this temperature myofibrillar proteins start denaturating. 24 people participated in the sensory evaluation, where they assessed sous vide cooked meat appearance, smell, taste, tenderness, moisture and rubberiness. At two lowest treating temperatures and times meats were more red and the higher the temperature rised the more brown meats became. Smell and taste were evaluated at lower temperatures resembled blood/metal and liver. At longer treatments that property changed to beef and boiled meat. 55 and 60 ℃ treated meats tenderness was rated tender and very tender, but at two higher temperatures tenderness was judged tough. Same trends were observed for moisture and rubberiness evaluation. Further research should be conducted to find time and temperature related property trends.
Kirjeldus
Magistritöö
Liha- ja piimatehnoloogia õppekaval
Märksõnad
magistritööd, veiseliha, sous vide, kvaliteediparameetrid, metoodikad