Lihatoodete lihasisalduse vähendamise võimalusi köögiviljade lisamisega
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Kuupäev
2021
Kättesaadav alates
03.09.2021
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Tasakaalustatud toitumine tähendab, et inimene tarbib päevas piisavas koguses mikro- ja makrotoitaineid ning päevane tarbitud energiakogus ei ületa tema päevast energiavajadust. RTE (ingl. k. ready-to-eat) ehk kohe tarbimiseks valmis lihatooted on leidnud tähtsa koha tänapäeva inimese enamasti ebatervislikus toitumises. Köögiviljad jällegi sisaldavad kasulikke kiudaineid, vitamiine, mineraalaineid ning on enamjaolt madala rasvasusega.
Käesoleva töö eesmärgiks oli erialase kirjanduse läbitöötamise ja eksperimentaalse osa abil uurida, kas värskete või külmutatud köögiviljadega on võimalik vähendada lihatoodete lihasisaldust toodete üldkvaliteeti oluliselt mõjutamata ning kuidas need taimsed lisandid mõjutavad lõpptoote füüsikalis-keemilisi, mikrobioloogilisi ning sensoorseid omadusi.
Töö eksperimentaalse osa raames valmistati kolmes katseseerias neli erineva koostisega kotletisegu – ilma lillkapsata kontrollsegu (KP) ning 10 ja 90% (10/90), 30 ja 70% (30/70) ning 50 ja 50% (50/50) vastavalt lillkapsa ja seahakkliha omavaheliste protsentuaalsete jagunemistega segud. Kuumtöödeldud jahutatud kotlette säilitati pakendatuna katsepäevade lõpuni (15 päeva) ning kuumtöötlemata ja -töödeldud (osa termiliselt töödeldud partiist ka sügavkülmutati) toodetel mõõdeti või arvutati kindlatel päevadel tuha-, valgu-, rasva-, niiskuse-, kiudainete- ja süsivesikute sisaldused, mõõdeti pH-d, vee aktiivsust, värvust, lõiketugevust, arvutati kuumtöötlemiskadu ja hinnati mikroobide üldarvu. Kuumtöödeldud kotlettidega (k.a sügavkülmutatud) viidi läbi sensoorne hindamine. Põhitoorainena kasutatud seahakklihal ja lillkapsal mõõdeti pH-d ning niiskuse-, tuha- ja valgusisaldust, hakklihal veel lisaks rasva- ja lillkapsal kiudainete sisaldust. Tulemustest selgus, et lillkapsa sisalduse suurenemine tõstis oluliselt kuumtöötlemata ja -töödeldud kotlettide pH-väärtust ja niiskusesisaldust ning langetas oluliselt rasva-, valgu- ja tuhasisaldusi. Tulemused olid tingitud lillkapsa kõrgemast pH-väärtusest ja niiskusesisaldusest ning madalamast valgu-, rasva- ja tuhasisaldusest võrdluses seahakklihaga. Säilitamine langetas osalist kuumtöödeldud KP ja 50/50 pH-d, mis võis olla tingitud pakkegaasina kasutatud CO2 mõningase imendumisega toodetesse. Kuumtöötlemiskaos olulisi erinevusi ei tuvastatud. Kuumtöödeldud suurema lillkapsa osakaaluga toodetes tõusis vee aktiivsus ja langes lõiketugevus, mille põhjustas lihavalkude osakaalu vähenemine ning lillkapsas sisalduvate kiudainete väiksem võimekus vett siduda võrdluses lihavalkudega. Sügavkülmutatud toodete vee aktiivsus oli kõrgem, sest külmutamise tagajärjel muutus immobiliseeritud vesi vabaks veeks. Suurema lillkapsa osakaaluga kuumtöödeldud kotlettide välis- ja lõikepindade L*- ja b*-väärtused tõusid ning a*-väärtused langesid oluliselt, põhjustatuna lillkapsa valkjast värvusest. Osadel juhtudel tõstis säilitamine toodete heledust ning langetas punasust, mida võib osaliselt põhjendada pakendusgaasi CO2 mõjuga toodete värvusele, mis vähemalt liha puhul toob kaasa viimase värvuse helenemise. Samas peaks erinevatele allikatele tuginedes modifitseeritud atmosfääris pakendamine (CO2 ja N2) toodete värvust hoopis stabiliseerima. Kuumtöötlemata 50/50 segu mikroobide üldarv oli võrdluses KP-ga oluliselt madalam. Lillkapsa lisamine ei toonud kaasa kuumtöödeldud toodete mikroobide üldarvu kasvu (kõrgeimad näitajad KP ja 10/90 segul), mis võis olla tingitud lillkapsa teatud antimikroobsest mõjust. 8. säilituspäeva näitajad olid oluliselt kõrgemad 4. ja 15. päeva mikroobide üldarvust. Kõik valmistatud tooted olid kogu 15-päevase säilitamisperioodi vältel mikroobide üldarvu poolest mikrobioloogiliselt ohutud.
Sensoorsel hindamisel selgus, et suurema lillkapsa osakaaluga toodete heledam värvus, suurem niiskusesisaldus ja madalam lõiketugevus langetasid oluliselt vastavalt nende välimuse ja lõikepinna värvuse hindeid ning tõstsid mahlasuse ja tekstuuri hindeid. Lillkapsa lisamine tõstis teatud määrani (kuni 30/70 seguni) oluliselt toodete maitse ja üldise meeldivuse hindeid.
Täiendavalt tuleks teostada enim aktsepteeritud toodetele (30/70) pikemad säilivuskatsed, uurida täpsemalt lillkapsa mõju lihatoodete kiudainete sisaldusele ning köögiviljade mõju lihatoodete vitamiinisisaldusele ja oksüdatsiooniprotsessidele.
A balanced diet is based on the fact that a person consumes sufficient amounts of micro- and macronutrients per day, and the daily amount of energy consumed does not exceed its daily energy needs. RTE (ready-to-eat) meat products have found an important place in today’s people’s mostly unhealthy diets. Vegetables, on the other hand, contain useful fibers, vitamins and minerals and are predominantly low in fat. The aim of this master’s thesis was to find out with the help of scientific literature and experimental part whether fresh or frozen vegetables can reduce meat content in meat products without significantly affecting the overall quality of the products and how these plant additives affect the physico-chemical, microbiological and sensory properties of the final product. In the experimental part of the thesis, four cutlet mixes of different compositions were prepared in three series of experiments – control mixture without cauliflower (KP) and 10 and 90% (10/90), 30 and 70% (30/70) and 50 and 50% (50/50) mixtures with the percentages showing the percentage distributions between cauliflower and minced pork, respectively. The thermally treated cutlets were cooled, packaged and stored for 15 days and on certain days for both raw and cooked (part of the heat-treated batch was also frozen) cutlets ash, protein, fat, moisture, fiber and carbohydrate contents were measured or calculated, the pH, water activity, colour and shear force were measured, cooking loss was calculated and the total viable count (TVC) was evaluated. Sensory evaluation was performed with thermally treated cutlets (including frozen). The pH and moisture, ash and protein content of the minced pork and cauliflower used as the main raw materials were measured, also the fat content in minced pork and fiber content in cauliflower were found. The results showed that the increase in cauliflower content significantly increased the pH and moisture content of uncooked and cooked cutlets and significantly reduced the fat, protein and ash contents. The results were due to the higher pH and moisture content and the lower protein, fat and ash content of cauliflower compared to minced pork. Storaging partially lowered the pH of heat-treated KP and 50/50, which may be due to some absorption of CO2 used as packaging gas into the products. No significant differences were found in cooking loss. The water activity and shear force of heat-treated products with a higher proportion of cauliflower increased and decreased, respectively, due to a decrease in the proportion of meat proteins and a lower water binding capability of the fibers in cauliflower compared to meat proteins. The water activity of frozen products was higher because of the alteration of immobilized water to free water. The L*- and b*-values of the outer and cutting surfaces of heat-treated cutlets with a higher proportion of cauliflower increased and the a*-values decreased significantly due to the whitish colour of cauliflower. In some cases, storage increased lightness and reduced redness of the products, which can be partly explained by the effect of the packaging gas (CO2) on the colour of products, which, at least for meat, causes the lightening of aforementioned. However, based on various sources, packaging in a modified atmosphere (CO2 and N2) should instead stabilize the colour of the products. TVC in the raw 50/50 mixture was significantly lower compared to KP. The addition of cauliflower did not cause an increase in TVC in the heat-treated products (highest values in KP and 10/90), which may have been due to the antimicrobial effect of cauliflower. TVC on storage day 8 was significantly higher than on days 4 and 15. All products were microbiologically safe in terms of TVC throughout the 15-day storage period. Sensory evaluation revealed that the brighter colour, higher moisture content and lower shear force of the products with a higher proportion of cauliflower significantly lowered their appearance and cutting surface colour scores and increased the juiciness and texture scores, respectively. The addition of cauliflower significantly increased the taste and overall acceptability scores of the products to a certain extent (up to 30/70). In addition, longer shelf-life studies should be performed on the best-received products (30/70), also the effect of cauliflower on the fiber content of meat products and the effect of vegetables on the vitamin content and oxidation processes of meat products should be thoroughly scrutinized.
A balanced diet is based on the fact that a person consumes sufficient amounts of micro- and macronutrients per day, and the daily amount of energy consumed does not exceed its daily energy needs. RTE (ready-to-eat) meat products have found an important place in today’s people’s mostly unhealthy diets. Vegetables, on the other hand, contain useful fibers, vitamins and minerals and are predominantly low in fat. The aim of this master’s thesis was to find out with the help of scientific literature and experimental part whether fresh or frozen vegetables can reduce meat content in meat products without significantly affecting the overall quality of the products and how these plant additives affect the physico-chemical, microbiological and sensory properties of the final product. In the experimental part of the thesis, four cutlet mixes of different compositions were prepared in three series of experiments – control mixture without cauliflower (KP) and 10 and 90% (10/90), 30 and 70% (30/70) and 50 and 50% (50/50) mixtures with the percentages showing the percentage distributions between cauliflower and minced pork, respectively. The thermally treated cutlets were cooled, packaged and stored for 15 days and on certain days for both raw and cooked (part of the heat-treated batch was also frozen) cutlets ash, protein, fat, moisture, fiber and carbohydrate contents were measured or calculated, the pH, water activity, colour and shear force were measured, cooking loss was calculated and the total viable count (TVC) was evaluated. Sensory evaluation was performed with thermally treated cutlets (including frozen). The pH and moisture, ash and protein content of the minced pork and cauliflower used as the main raw materials were measured, also the fat content in minced pork and fiber content in cauliflower were found. The results showed that the increase in cauliflower content significantly increased the pH and moisture content of uncooked and cooked cutlets and significantly reduced the fat, protein and ash contents. The results were due to the higher pH and moisture content and the lower protein, fat and ash content of cauliflower compared to minced pork. Storaging partially lowered the pH of heat-treated KP and 50/50, which may be due to some absorption of CO2 used as packaging gas into the products. No significant differences were found in cooking loss. The water activity and shear force of heat-treated products with a higher proportion of cauliflower increased and decreased, respectively, due to a decrease in the proportion of meat proteins and a lower water binding capability of the fibers in cauliflower compared to meat proteins. The water activity of frozen products was higher because of the alteration of immobilized water to free water. The L*- and b*-values of the outer and cutting surfaces of heat-treated cutlets with a higher proportion of cauliflower increased and the a*-values decreased significantly due to the whitish colour of cauliflower. In some cases, storage increased lightness and reduced redness of the products, which can be partly explained by the effect of the packaging gas (CO2) on the colour of products, which, at least for meat, causes the lightening of aforementioned. However, based on various sources, packaging in a modified atmosphere (CO2 and N2) should instead stabilize the colour of the products. TVC in the raw 50/50 mixture was significantly lower compared to KP. The addition of cauliflower did not cause an increase in TVC in the heat-treated products (highest values in KP and 10/90), which may have been due to the antimicrobial effect of cauliflower. TVC on storage day 8 was significantly higher than on days 4 and 15. All products were microbiologically safe in terms of TVC throughout the 15-day storage period. Sensory evaluation revealed that the brighter colour, higher moisture content and lower shear force of the products with a higher proportion of cauliflower significantly lowered their appearance and cutting surface colour scores and increased the juiciness and texture scores, respectively. The addition of cauliflower significantly increased the taste and overall acceptability scores of the products to a certain extent (up to 30/70). In addition, longer shelf-life studies should be performed on the best-received products (30/70), also the effect of cauliflower on the fiber content of meat products and the effect of vegetables on the vitamin content and oxidation processes of meat products should be thoroughly scrutinized.
Kirjeldus
Magistritöö
Toiduainete tehnoloogia õppekaval
Märksõnad
magistritööd, sealiha, kotlet, lillkapsas, mikroobide üldarv, sensoorika