[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,v...[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,vacuum freeze drying,microwave vacuum drying,drum drying and spray drying were measured and analyzed to explore the effects of different drying methods on quality characteristics of Chinese wolfberry powder. [Results] The total sugar content and reducing sugar contents of product: vacuum freeze drying > spray drying > microwave vacuum drying > drum drying > hot air drying; carotene and total flavonoid contents: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; after drying process,the dietary fiber content of product obtained by drum drying and spray drying was relatively higher,while the Vc content of Chinese wolfberry powder prepared by vacuum freeze drying was the highest. a~*value( redness to greenness) of color: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; the Chinese wolfberry powder prepared by vacuum freeze drying had the best solubility,hygroscopicity and rehydration ratio. [Conclusions] Microwave vacuum drying was the best method to prepare Chinese wolfberry powder,in order to keep its quality and consider the cost of production.展开更多
Two-year-old Medicago sativa at budding initial stage was taken as research materials.Five methods were used to make green hay,including flatting stems + spraying 2.5% K2CO3,flatting stems,sun curing,drying in shade ...Two-year-old Medicago sativa at budding initial stage was taken as research materials.Five methods were used to make green hay,including flatting stems + spraying 2.5% K2CO3,flatting stems,sun curing,drying in shade and drying under 105 ℃ condition(CK).Besides,effects of different green hay making methods on dry characteristics and nutritional quality of M.sativa green hay were studied,and a comprehensive evaluation of M.sativa green hays was conducted.Results showed that,except CK,the drying rates in other making methods were all fast at first,and then slow down.Both of drying under 105 ℃ condition and flatting stems + spraying K2CO3 could speed up drying rate and reduce nutritional losses of green hay.Sun curing could also speed up drying rate,but it could not maintain the quality of green hay.The results of Grey Relational Analysis on five green hay making methods indicated that CK had the best comprehensive performance,followed by green hays made by flatting stems + spraying K2CO3.Therefore,flatting stems + spraying K2CO3 was a quick and easy method to make green hay,and it was worth to be recommended in practical production.展开更多
In this study kokum rind dried by different methods,i.e.open air sun drying,solar drying and the convective hot air drying(60℃)was taken after being packaged in gunny bags,nylon bags and plastic jars for storage stud...In this study kokum rind dried by different methods,i.e.open air sun drying,solar drying and the convective hot air drying(60℃)was taken after being packaged in gunny bags,nylon bags and plastic jars for storage study upto nine months.The effect of different drying methods on quality parameters i.e.acidity,pH,TSS,reducing sugar,non-reducing sugar,colour(L,a and b)and calorific value of the stored product were evaluated.The quality parameters were tested at three-month intervals.Among three packaging materials,plastic jar was found best for kokum rind storage upto nine months as compared with nylon and gunny bags.Deterioration occurred as changes in acidity,non-reducing sugar,lightness,redness and calorific value over the storage period from the 0^(th) to the 9^(th) month.However,the TSS and b value increased as storage duration extended.展开更多
基金Supported by National Science and Technology Support Plan Program(2016-YFD0400704-3)
文摘[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,vacuum freeze drying,microwave vacuum drying,drum drying and spray drying were measured and analyzed to explore the effects of different drying methods on quality characteristics of Chinese wolfberry powder. [Results] The total sugar content and reducing sugar contents of product: vacuum freeze drying > spray drying > microwave vacuum drying > drum drying > hot air drying; carotene and total flavonoid contents: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; after drying process,the dietary fiber content of product obtained by drum drying and spray drying was relatively higher,while the Vc content of Chinese wolfberry powder prepared by vacuum freeze drying was the highest. a~*value( redness to greenness) of color: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; the Chinese wolfberry powder prepared by vacuum freeze drying had the best solubility,hygroscopicity and rehydration ratio. [Conclusions] Microwave vacuum drying was the best method to prepare Chinese wolfberry powder,in order to keep its quality and consider the cost of production.
基金Supported by Tibet High Quality Freeze Resistance Bluegrass Varieties Breeding(Z2013C02N02_02)National Wool Sheep Grazing Grassland Ecological Position of Scientific Research Project(CARS-40-09B)
文摘Two-year-old Medicago sativa at budding initial stage was taken as research materials.Five methods were used to make green hay,including flatting stems + spraying 2.5% K2CO3,flatting stems,sun curing,drying in shade and drying under 105 ℃ condition(CK).Besides,effects of different green hay making methods on dry characteristics and nutritional quality of M.sativa green hay were studied,and a comprehensive evaluation of M.sativa green hays was conducted.Results showed that,except CK,the drying rates in other making methods were all fast at first,and then slow down.Both of drying under 105 ℃ condition and flatting stems + spraying K2CO3 could speed up drying rate and reduce nutritional losses of green hay.Sun curing could also speed up drying rate,but it could not maintain the quality of green hay.The results of Grey Relational Analysis on five green hay making methods indicated that CK had the best comprehensive performance,followed by green hays made by flatting stems + spraying K2CO3.Therefore,flatting stems + spraying K2CO3 was a quick and easy method to make green hay,and it was worth to be recommended in practical production.
文摘In this study kokum rind dried by different methods,i.e.open air sun drying,solar drying and the convective hot air drying(60℃)was taken after being packaged in gunny bags,nylon bags and plastic jars for storage study upto nine months.The effect of different drying methods on quality parameters i.e.acidity,pH,TSS,reducing sugar,non-reducing sugar,colour(L,a and b)and calorific value of the stored product were evaluated.The quality parameters were tested at three-month intervals.Among three packaging materials,plastic jar was found best for kokum rind storage upto nine months as compared with nylon and gunny bags.Deterioration occurred as changes in acidity,non-reducing sugar,lightness,redness and calorific value over the storage period from the 0^(th) to the 9^(th) month.However,the TSS and b value increased as storage duration extended.