Sensory Evaluation of Freeze-Dried Facial Mask and Analysis of User Profile

To thoroughly understand market opportunity of freeze-dried facial mask and deeply get insight of consumers’usage behavior and needs,evaluate sensory feelings of 10 screened commercial freeze-dried facial mask products,group test products according to the differences of sensory attributions via Principal Component Analysis(PCA)and Agglomerative Hierarchical Clustering(AHC),pick up the representative products.Freeze-dried facial mask users evaluate satisfaction degree of picked up products and participate survey of usage behavior/cognition.Analyze consumer data by AHC to get consumer segmentations and their profile.The test results show that,sensory data and consumer data,which is from consumers test of screened representative products by performing PCA and AHC on sensory data,can be verified mutually.It is helpful to understand the needs of consumer segmentations and reason to buy by combining sensory data and consumer test.

Ag/TiO_2/freeze-dried graphene nanocomposite as a high performance photocatalyst under visible light irradiation

Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, reduction of graphene oxide and loading of Ag/TiO2nanoparticles on graphene sheets were achieved. Investigation of chemical state of products showed that covering of Ag/TiO2surface with higher weight ratio of graphene resulting in that Ag metals in Ag/TiO2were oxidized to Ag2 O in nanocomposite structure after solvothermal process. Degree of photocatalytic activity enhancement strongly depends on the coverage of Ag/TiO2surface by porous graphene. The sample of 1 wt% porous graphene hybridized Ag/TiO2showed the highest photocatalytic activity, which is related to high migration efficiency of photoinduced of electrons and reduction of electron–hole recombination rate due to high electrical conductivity of graphene. Expanding of absorption to visible light region was ascribed to surface plasmon resonance effect of Ag metals and presence of graphene. Investigation of photocatalytic performance of formic acid as a dye-less organic pollutant showed that dye sensitization effect of Rh B molecules during evaluation of photocatalytic performance was negligible.

Study of self-made freeze-dried bilayered fibrin-binding amniotic membrane in ocular trabeculectomy in rabbits

AIM: To investigate the antifibrotic effect of freeze-dried bilayered fibrin-binding amniotic membrane on trabeculectomy in a rabbit model. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with natural bilayered fibrin-binding amniotic membrane) and the blank group (single trabeculectomy). Clinical observation, hematoxylin-eosin staining, Massion staining, real-time PCR and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. RESULTS: Statistical differences were noted in survival. analysis and intraocular pressure(IOP) among groups on days 7, 14, 21 and 30 following surgery. Histology, immunohistochemistry and real-time PCR further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane resulted in good wound healing and no scar formation. CONCLUSION: Self-made freeze-dried bilayered fibrin-binding amniotic membrane may inhibit the formation of scarring in glaucoma after trabeculectomy.

Efficacy of Yiqi Fumai (Freeze-Dried Powder) on Ischemic Diastolic Heart Failure

Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) were selected randomly. 52 patients with TCM syndrome of qi-yin deficiency were divided into Chinese and Western combination therapy group. 48 patients have no TCM syndrome of qi-yin deficiency, and were treated with standard western medicine. After treatment, Seattle Angina Questionnaire Evaluation, ECG, conventional and stress echocardiography (SE) index, NT-proBNP were compared between before and after treatment. Results: The differences of PL, TS, DP between before and after treatment by YFP were statistically significant

Component Analysis of Shuanghuanglian Freeze-dried Powder and Its Effects on Human Hepatocyte Function when Combined with Cefradine

[Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in combination with cefradine.[Methods]High performance liquid chromatography(HPLC)was used to detect the contents of baicalin,wogonin,chlorogenic acid and forsythin,the main components of Shuanghuanglian freeze-dried powder.HL-7702 cells were cultured with Shuanghuanglian freeze-dried powder and the main components of Shuanghuanglian freeze-dried powder alone or in combination with cefradine.Enzyme linked immunosorbent assay(ELISA)was used to detect the contents of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in the cell supernatant after culture,and HPLC was used to detect the expression level of adenosine diphosphate(ADP)and adenosine triphosphate(ATP);agarose gel electrophoresis was used to detect the expression of cyclooxygenase 2(COX-2)and heme oxygenase-1(HO-1)in HL-7702 cells.[Results]In Shuanghuanglian freeze-dried powder for injection,the content of baicalin was the highest,and the content of wogonin was the lowest.Compared with the control group,the expressions of AST and ALT in human hepatocytes(HL-7702)in high-dose baicalin group,forsythin group and wogonin group decreased(P<0.05,P<0.01),while the expression of ALT in chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)increased(P<0.05,P<0.01),and the expression of AST had no significant difference(P>0.05);the results in the low-dose group were similar to those in the high-dose group.Compared with the control group,ATP expression in chlorogenic acid group,chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)in the high-dose group decreased(P<0.05,P<0.01),and ADP expression was not significantly different(P>0.05);in the low-dose group,the expression of ATP and ADP increased in baicalin group(P<0.05),but decreased in wogonin group,baicalin+cefradine group(0.046 mg/mL)and wogonin group+cefradine group(0.046 mg/mL)(P<0.05,P<0.01).Compared with the control group,the expressions of COX-2 and HO-1 in HL-7702 cells in the cefradine group showed no significant difference(P>0.05).The expression of HO-1 and COX-2 in the different dose groups of Shuanghuanglian and the group combined with cefradine increased,and the difference was significant(P<0.05,P<0.01).[Conclusions]The components of Shuanghuanglian freeze-dried powder for injection had effects on hepatocytes,of which baicalin had a significant effect,and the effect of cefradine on hepatocytes was increased when used in combination with cefradine.

Viability of Two Freeze-dried Strains of Bifidobacterium Preparations at Various Temperatures during Prolonged Storage

Viability of bifidobacteria in freeze-dried probiotic products at various temperatures during prolonged storage was assessed. Bifidobacterium longum and Bifidobacterium infantis were freeze-dried. The freeze-dried preparations were stored at -18 , 4 , and 20 ℃. Cell counts were enumerated using BS agar at 37 ℃ for 48 h under anaerobic conditions at 0, 45 and 120 days. Storage at 20 ℃ showed the greatest decline in the viability of bifidobacteria, whereas that at -18 ℃ showed the least decrease.

Trial productions of freeze-dried Lactobacillus plantarum culture using dairy by-products as cryoprotectants:Viability and characterization of cultures

This study is a research on the utilization of dairy industry by-products in the practical production and long-term preservation of industrial microbial cultures.Accordingly,lyophilized cultures were obtained by freeze-drying of Lactobacillus plantarum bacteria in large quantities and for a constant period of time in skimmed milk-based medium containing 5%acid casein,rennet casein,whey and demineralized whey.The cryoprotectants did not have significant protection against freeze-drying process,moreover,the use of rennet casein significantly reduced viability.The efficiency of the preservatives in preserving the viability during storage was very successful compared to the control culture.Casein-enriched cultures had high water activity and moisture,but high viability was maintained during storage.The powder morphologies of the cultures were differentiated by the use of different cryoprotectants.Particle sizes of the cultures were parallel to the moisture content.Particle size and distribution increased with storage.By thermogravimetric analysis(TGA)and differential scanning calorimetry(DSC)analysis,it was determined that the addition of casein protein increased the degradation temperature of the cultures.The production of freeze-dried cultures became difficult with the use of casein.However,it was generally concluded that the protective properties of skimmed milk used for the preservation of L.plantarum could be improved by the addition of dairy by-products as a protective agent.

High-concentration dispersions of exfoliated MoS2 sheets stabilized by freeze-dried silk fibroin powder

Liquid-phase exfoliation （LPE） is an attractive method for the scaling-up of exfoliated MoS2 sheets compared to chemical vapor deposition and mechanical cleavage. However, the MoS2 nanosheet yield from LPE is too small for practical applications. We report a facile method for the scaling-up of exfoliated MoS2 nanosheets using freeze-dried silk fibroin powders. Compared to MoS2 dispersion in the absence of silk fibroin powder, sonicated MoS2 dispersions with silk fibroin powder （MoSJSilk dispersion） show noticeably higher exfoliated MoS2 nanosheet yields, with suspended MoS2 concentrations in MoS2/Silk dispersions sonicated for 2 and 5 h of 1.03 and 1.39 mg.mL-1, respectively. The MoS2 concentration in the MoS2/Silk dispersion after centrifugation above 10,000 rpm is more than four times that without the silk fibroin. The size of the dispersed silk fibroin is controlled by the change of centrifugation rate, showing the removal of silk fibroin above tens of micrometers in size after centrifugation at 2,000 rpm. Size-controlled silk fibroin biomolecules combined with MoS2 nanosheets are expected to increase the practical use of such materials in fields related to tissue engineering, biosensors and electrochemical electrodes. Atomic force microscopy and Raman spectroscopy provide the height of the MoS2 nanosheets spin-cast from MoS2/Silk dispersions, showing thicknesses of 3--6 nm. X-ray photoelectron spectroscopy and X-ray diffraction indicate that the outermost surface layer of the hydrophobic MoS2 crystals interact with oxygen-containing functional groups that exist in the hydrophobic part of silk fibroins. The amphiphilic properties of silk fibroin combined with the MoS2 nanosheets stabilize dispersions by enhancing solvent-material interactions. The large quantities of exfoliated MoS2 nanosheets suspended in the as-synthesized dispersions can be utilized for the fabrication of vapor and electrochemical devices requiring high MoS2 nanosheets contents.

Experimental study on rehydration conditions of freeze-dried platelets

A rehydration process for freeze-dried human platelets was studied on 1 ml of samples. The effects of prehydration duration, prehydration temperature, an rehydration solution on the recovery rate, mean platelet volume （MPV）, and platelet distribution width （PDW） were investigated. The mass changes during the prehydration process were also studied. Three prehydration durations： 0, 1.5, and 3.5 h, and two rehydration solutions： platelet-poor plasma and phosphate-buffered saline （PBS）, were tested. It was found that： （1） the prehydration was of significance; （2） 1.5 h of prehydration had better effects than 3.5 h of prehydration; （3） as a rehydration solution, the platelet-poor plasma behaved better than the PBS. The impacts of prehydration duration and temperature on the results were studied. There was almost no difference between 35 and 37 ℃. Among all the prehydration durations tested, 15, 30, 60, 90, and 120 min, the best result was achieved with the time duration of 15 min. The weights of prehydrated platelets at the end of each test were measured and the water contents were calculated. After 15 min ofprehydration, the water contents in the samples were about （4.8±0.01）% and （5.27±0.29）% （w/w） corresponding to the conditions of 35 and 37 ℃, respectively. These results will be helpful for further studies on the freeze-drying of mammalian cells.

Rapid Detection of Serum Procalcitonin by Immunochromatograghy Technology Based on Freeze-dried Up-conversion Nanoparticles/Antibody Conjugates

Procalcitonin （PCT） is a sensitive and specific biomarker for sepsis diagnosis and widely used as a biomarker to improve the diagnosis of bacterial infections and to guide the antibiotic therapy. In our work, an improved up-converting nanoparticle （UCP） technology based on the immunochromatographic assay （UPT-ICA） was developed for rapid and quantitative detection of PCT. In order to further improve the accuracy, sensitivity and stability of the assay on the basis of our previous study, the UCP coupling with rnonoclonal antibody of PCT （UCP-Abl） was freeze-dried under certain conditions. And the detections of PCT levels with UCP-Abl conjugates before and after freeze-drying were evaluated. The results show that, compared to the UCP-Abl conjugates without freeze-drying, the detection sensitivity of freeze-dried UCP-Abl is slightly improved, having a lower immunochromatogragh background and better stability. This improved method can provide a rapid, accurate, and relatively easy way for the clinical detection of PCT.

Chemical characterization, release, and bioactivity of Eucalyptus camaldulensis polyphenols from freeze-dried sodium alginate and sodium carboxymethyl cellulose matrix

Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, morphology, physicochemical parameters, and micromeritics properties. Antioxidant and antimicrobial activities of the microcapsules were also demonstrated. Results revealed an irregular-shaped microparticles with a mean diameter ranging from 6.7 to 26.6 μm. Zeta potential and polydispersity index ranged from −17.01 to 2.23 mV and 0.34 to 0.49, respectively. Percentage yield ranged between 70.4 and 81.5 per cent whereas encapsulation efficiency ranged between 74.2 ± 0.011 and 82.43 ± 0.77 per cent. Swelling index and solubility varied inversely with extract concentration, with a range of 54.4%-84.0% and 18.8%-22.2%, respectively. Antioxidant activities varied directly with the concentration of the extract. Minimum inhibitory and minimum bactericidal concentrations of the microcapsules against Gram-positive foodborne pathogens ranged from 0.19 to 3.12 and 0.19-12.25 mg/ml, respectively. The Higuchi model indicated a time-dependent, delayed, and regulated release of polyphenols at 37°C. The results suggested that alginate-CMC possessed good encapsulant properties that preserved the bioactive extract, thus might be employed for application of natural products in food systems.

Moisture sorption characteristics of freeze-dried human platelets

Freeze-drying is a promising method for a long-term storage of human platelets.The moisture sorption characteristics of freeze-dried human platelets(FDHPs) were studied in this paper.The moisture sorption isotherms of FDHPs and freeze-dried lyophilization buffer(FDLB) were measured at 4,25,and 37°C.The experimental data were fitted to Brunauer-Emmett-Teller(BET) and Guggenheim-Anderson-de Boer(GAB) equations.There were no sig-nificant statistical differences(P>0.05) between the sorption characteristics of FDHPs and FDLB at 4 and 25°C,while FDHPs absorbed more water at 37°C.The net isosteric heat of sorption was derived.The heat for FDHPs showed an abnormal negative value at low moisture contents when 25 and 37°C data were used.Dynamic sorption experiments were carried out at 25°C with environmental water activity controlled at 0.75,0.85,and 0.90.The moisture diffusion coefficient was fitted to be 8.24×10 -12 m 2 /s when experimental data at initial time were used.These results would be helpful in choosing prehydration and storage condition for FDHPs.

Preparation technology of ultra-fine powders of Auricularia auricular

Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine powders of edible fungus (Auricularia auricular). The content of basic nutrients, amino acid, micro structure and their properties of raw edible fungus and the edible fungus powders obtained with the two methods were analyzed and compared. The granularity size and micro-structure of the pulverized samples were analyzed by SEM and TEM technology. The average granularity size of the edible fungus powder obtained with mechanical method was 1–5 μm, while that obtained with mechanical method combined with vacuum freeze-drying process was 0.5–1 μm. The ultra-fine powders of edible fungus obtained with the two methods had better water recovery capability and quality, and their preserving time was longer than that of raw edible fungus. All the properties of the ultra-fine powders of edible fungus obtained with the vacuum freeze-drying technology were evidently superior to that of the conventional mechanical method. Keywords Auricularia auricula - Edible fungus - Ultra-fine powders - Vacuum freeze-drying CLC number TS205 Document code B Biography: YANG Chun-yu (1975), female, Ph. D. in Engineering Technology Center of Forestry and Wood Workine, Machinery, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong

Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia

Aim： To determine the effect of two different extracts of red maca in male rats. Methods： Prostatic hyperplasia was induced in male rats with testosterone enanthate （TE）. The study comprised six groups： one control group （group 1）, one group treated with TE （group 2）, two groups treated with TE and aqueous extract of red maca （groups 3 and 4）, one group treated with hydroalcoholic extract of red maca （group 5） and one group treated with finasteride （0.1 mg, group 6）. Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates （0.02-0.08 mg） in red maca extracts was assessed. Results： Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion： The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.

Comparisons of the effects of different drying methods on soil nitrogen fractions:Insights into emissions of reactive nitrogen gases(HONO and NO)

Reactive nitrogen(Nr)emission from soils,e.g.,nitrous acid(HONO)and nitric oxide(NO),is a key process of the global nitrogen(N)cycle and has significant implications for atmospheric chemistry.To understand the underlying mechanisms of soil Nr emissions,air-dried or oven-dried soils are commonly used in the laboratory.To date,few studies have compared the effects of different drying methods on soil Nr gas fluxes and N fractions.Here,the authors studied soil water content,pH,(in)organic N content,and Nr gas fluxes of air-dried,freeze-dried,oven-dried,and fresh soils from different land-use types.The results showed that the soil pH of air-dried and oven-dried samples was significantly lower compared with fresh soil from farmland and grassland,but higher compared with forest soil.The difference in soil pH between freeze-dried and fresh soil(mean±standard deviation:0.52±0.31)was the lowest.In general,all drying methods increased the soil NH4+-N,NO3−-N,and dissolved organic N contents compared with fresh soil(P<0.05).The maximum HONO and NO flux and total emissions during a full wetting–drying cycle of fresh soil were also increased by air-drying and oven-drying(P<0.001),but comparable with freeze-dried soil(P>0.2).In conclusion,all drying methods should be considered for use in studies on the land–atmosphere interface and biogeochemical N cycling,whereas the freeze-drying method might be better for studies involving the measurement of soil Nr gas fluxes.

Homemade lyophilized cross linking amniotic sustained-release drug membrane with anti-scarring role after filtering surgery in rabbit eyes

AIM: To investigate the antifibrotic effect of the freeze-dried bilayered fibrin-binding amniotic membrane as a drug delivery system on glaucoma surgery in rabbit model. The aim of this study was to prepare a novel local delivery system for the sustained and controllable release of 5-Fu. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with 5-Fu loaded freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with 5-Fu) and the blank group (single trabeculectomy). HE staining, massion staining and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. The concentration of 5-Fu in rabbit aqueous humor was examined by high performance liquid chromatography (HPLC) 3 days after the surgery. RESULTS: Statistical differences were noted in intraocular pressure among groups on day 7, 14, 21 and 30 following surgery. Histology further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane yielded well wound healing and no scar formation and was beneficial for long term effect. CONCLUSION: HPLC showed a good slow-release effect with freeze-dried bilayered fibrin-binding amniotic membrane.

Extraction of Phenolic Compounds from Olive Leaf Extracts and Their Effect on Proliferation of Human Carcinoma Cell Lines

The aim of this work was to evaluate the effect of different olive leaf extracts (OLE) from different leaf growing stages on human carcinoma cell lines. OLE were tested in human carcinoma cell lines in vitro and cells were plated in 96-microtiter culture plates for each OLE concentration. Fresh (F) and freeze-dried (FD) leaves exhibited phenolic compounds in the range of 2.09 ± 0.10 to 8.44 ± 0.64 and 7.72 ± 0.56 to 24.65 ± 1.9 mg gallic acid equivalents/g leaves, respectively. OLE from several Portuguese olive tree cultivars were found to inhibit the growth of human carcinoma cell lines in a range of 2.09 - 8.44 μg phenolic compound/well (209 - 844 μg/ml) and 0.07 - 2.40 μg phenolic compounds/well (7 - 240 μg/ml) for fresh and freeze-dried leaves, respectively. Young (Y) leaves have revealed the highest cell growth inhibition ranging from about 95% for Cobran?osa, followed by 90% for Cobran?osa, 90% for Arbequina and 75% for Arbequina for cell lines A549, HeLa, A431 and OE21, respectively. The lowest cell growth inhibition (35%) was observed for Galega (Y) leaf extract on cell line A549. However, FD samples exhibited a distinctive pattern since cell growth inhibition was highest at highest extract dilution tested, for A431 (Galega Y) followed by A549 (Cobran?osa Y) with cell inhibition of 75% and 70%, respectively. The data presented in this work strongly suggest that OLEs inhibit the growth of human carcinoma cell lines.

Physicochemical Properties and Sensory Evaluation of Sponge Cake Supplemented with Hot Air and Freeze Dried Oyster Mushroom (<i>Pleurotus sajor-caju</i>)

The study was aimed to enhance the nutritional quality of sponge cakes with oyster mushroom (Pleurotus sajor-caju). In this study, the physicochemical, functional, and sensory properties of cake supplemented with five different levels of mushroom powder (0 as control, 5%, 7%, 10%, and 12%) were evaluated. The results revealed that both hot air dried (HD) and freeze dried (FD) mushroom powder contained a higher amount of protein, fat, ash and fiber ontent compared with wheat flour used in cake, but the carbohydrate and moisture content showed the reverse trend. The study also found that increasing the level of fortification from 0% to 12% mushroom powder also increased the protein, fat, ash, and fiber content in the cake. FD mushroom powder significantly (p ≤ 0.05) recorded the highest protein (11.72% - 15.16%), fat (20.01% - 21.9%), ash (1.75% - 1.92%), and fiber (1.39% - 1.74%) with increasing the level of supplementation from 5% - 12%. In contrast, carbohydrate content of cake decreased from 34.13% - 31.15% with increasing the level of FD mushroom from 5% - 12%. Also, the volume and weight of the cake with FD mushroom were higher compared to HD and control sample. The results of sensory evaluation indicated that sponge cake with 10% FD oyster mushroom was rated the most acceptable after the control.

Facile synthesis of Li3V2（PO4）3/C cathode material for lithium-ion battery via freeze-drying

In this work, we report a facile route for the synthesis of Li3V2(PO4)3/C cathode material via freezedrying and then calcination. The effect of calcination temperature on the electrochemical properties of the Li3V2(PO4)3/C is also investigated. When used as a lithium-ion battery cathode, the optimized Li3V2(PO4)3/C (LVP-800) through calcination at 800 ℃ exhibits a high initial charge and discharge capacity. The excellent electrochemical performance of LVP-800 is attributed to the good crystallinity and uniform morphology of the electrode material. In addition, the residual carbon can also improve the conductivity and buffer the volume expansion during the Li-ion extraction/reinsertion. Meanwhile, charge compensation also plays an important role in excellent electrochemical performance.

Optimizing the Chemical Compositions of Protective Agents for Freeze-drying Bifidobacterium longum BIOMA 5920

Freeze drying has a deleterious effect on the viability of microorganisms. In front of this difficulty, the present study adopts response surface methodology to optimize the chemical compositions of protective agents to seek for maximum viability of Bifidobacterium longum BIOMA 5920 during freeze-drying. Through the compara- tive analysis of single protectant, the complex protective agents show better effect on the Bifidobacterium viability. Human-like collagen (HLC), trehalose and glycerol are confirmed as significant factors by Box-Behnken Design. The optimized formula for these three variables is tested as follows: HLC 1.23%, trehalose 11.50% and glycerol 4.65%. Under this formula, the viability is 88.23%, 39.67% higher in comparison to the control. The viable count is 1.07×10 9 cfu·g-1 , greatly exceeding the minimum viable count requirement (10 6 cfu·g-1 ).