The key processing parameters for yak milk and yogurt are not well established.To investigate the effects of physical processing methods on the physicochemical properties of yak milk and yogurt, ultrasonic treatment (30, 60, 90, 120, 150 W) and pressure treatment (10, 15, 20, 25, 30 MPa) were employed for the pre-processing of yak milk, which was then fermented to produce yak yogurt.By analyzing physicochemical indicators such as pH, titratable acidity, color variation, and turbidity of yak milk, the reasons for the changes in physicochemical properties caused by ultrasonic and pressure treatments were identified.Additionally, the pH, titratable acidity, color, antioxidant activity, stability, apparent viscosity, and texture properties of yak yogurt under different treatments were measured, and a comprehensive evaluation was conducted using correlation analysis to elucidate the impact of different processing methods on the physicochemical properties of yak yogurt.The mechanism by which ultrasonic and pressure treatments affected the quality of yak yogurt was elucidated.Results indicated that pressure treatment had a minimal impact on the physicochemical properties of yak milk.The process did not alter the composition of yak milk. The process did not alter the composition of yak milk but improved the stability of its components, therefore, it was suitable for the pre-processing of liquid yak milk.However, the stability, viscosity, and texture properties of yak yogurt were significantly improved by ultrasonic treatment. The water-holding capacity was increased by 22.33%, and the viscosity and hardness were increased by 17.08 Pa·s and 91.51 g, respectively.Correlation analysis clearly showed the relationships between various indicators of yak yogurt after ultrasonic and pressure treatments, which provided theoretical guidance for the quality control of yak yogurt.The results provided theoretical guidance and new methods for the initial processing of milk and the improvement of yogurt quality and stability.
[1] 杨国武, 张娟香, 路建卫, 等.美仁牦牛乳品质特性分析[J].中国草食动物科学, 2023, 43(2):28-32.
YANG G W, ZHANG J X, LU J W, et al.Analysis of milk quality characteristics in meiren yak[J].China Herbivore Science, 2023, 43(2):28-32.
[2] 雷昌贵, 孟宇竹, 陈锦屏, 等.冻藏条件对牦牛原料乳品质的影响[J].中国食品添加剂, 2023, 34(8):147-155.
LEI C G, MENG Y Z, CHEN J P, et al.Effect of freezing conditions on the quality of raw milk from yaks[J].China Food Additives, 2023, 34(8):147-155.
[3] 宋雪梅, 马安娜, 刘炫妍, 等.不同冷藏时间牦牛乳中细菌群落结构和理化性质比较[J].现代食品科技, 2022, 38(7):126-132; 62.
SONG X M, MA A N, LIU X Y, et al.Comparison of bacterial communities and physicochemical properties in yak milk with different cold storage durations[J].Modern Food Science and Technology, 2022, 38(7):126-132; 62.
[4] KENARI R E, RAZAVI R.Effect of sonication conditions:Time, temperature and amplitude on physicochemical, textural and sensory properties of yoghurt[J].International Journal of Dairy Technology, 2021, 74(2):332-343.
[5] SFAKIANAKIS P, TOPAKAS E, TZIA C.Comparative study on high-intensity ultrasound and pressure milk homogenization:Effect on the kinetics of yogurt fermentation process[J].Food and Bioprocess Technology, 2015, 8(3):548-557.
[6] CHOI I, ZHONG Q X.Physicochemical properties of skim milk powder dispersions after acidification to pH 2.4-3.0 and heating[J].Food Hydrocolloids, 2020, 100:105435.
[7] 卢野. 混合驴乳发酵配方优化及体外抗氧化研究[D].阿拉尔:塔里木大学, 2021.
LU Y.Optimization of fermentation formula and in vitro antioxidation of mixed donkey milk[D].Ala’er:Tarim University, 2021.
[8] 罗丽, 宋礼, 张晓梅.基于斑马鱼模型和体外抗氧化评价甘南牦牛乳抗氧化效果[J].食品与发酵工业, 2024,50(24):133-138.
LUO L, SONG L, ZHANG X M.Antioxidant effect of Gannan yak milk based on zebrafish model and antioxidant in vitro[J].Food and Fermentation Industries, 2024,50(24):133-138.
[9] 李爽, 刘小芳, 冷凯良, 等.大西洋鳕鱼骨胶原蛋白肽的抗氧化活性及稳定性研究[J].食品与发酵工业, 2024, 50(16):50-56.
LI S, LIU X F, LENG K L, et al.Antioxidant activity and stability of collagen peptides from Atlantic cod (Gadus morhua) bone[J].Food and Fermentation Industries, 2024, 50(16):50-56.
[10] 车皞祺, 艾连中, 夏永军, 等.嗜热链球菌胞外多糖EPS333对酸乳品质的影响[J].工业微生物, 2019, 49(2):25-31.
CHE H Q, AI L Z, XIA Y J, et al.Effects of Streptococcus thermophilus exopolysaccharide EPS333 on the quality of yogurt[J].Industrial Microbiology, 2019, 49(2):25-31.
[11] CALAMARI L, GOBBI L, BANI P.Improving the prediction ability of FT-MIR spectroscopy to assess titratable acidity in cow’s milk[J].Food Chemistry, 2016, 192:477-484.
[12] PEGU K, ARYA S S.Comparative assessment of HTST, hydrodynamic cavitation and ultrasonication on physico-chemical properties, microstructure, microbial and enzyme inactivation of raw milk[J].Innovative Food Science & Emerging Technologies, 2021, 69:102640.
[13] 范小雪. 超声辅助添加寡肽的羊乳制品品质及功能特性的研究[D].济南:齐鲁工业大学, 2023.
FAN X X.Study on the quality characteristic and functionality of goat milk products with the additive of oligopeptides assisted by ultrasound[D].Jinan:Qilu University of Technology, 2023.
[14] JIA D, YOU J, HU Y, et al.Effect of CaCl2 on denaturation and aggregation of silver carp myosin during setting[J].Food Chemistry, 2015, 185:212-218.
[15] KHAIRUNNISA S, KAYAPUTRI I L, UTAMA G L.Study of the addition hull of mung bean sprouts extract to pH and characteristic of sensory yogurt probiotic[J].Jurnal Ilmu Dan Teknologi Hasil Ternak, 2019, 14(2):99-106.
[16] 庞幸, 梁燕子, 胥保辉, 等.不同贮藏温度对常见低温酸奶品质的影响[J].中国乳业, 2024(6):96-102; 108.
PANG X, LIANG Y Z, XU B H, et al.Effects of different storage temperatures on common low-temperature yogurt quality[J].China Dairy, 2024(6):96-102; 108.
[17] RIENER J, NOCI F, CRONIN D A, et al.The effect of thermosonication of milk on selected physicochemical and microstructural properties of yoghurt gels during fermentation[J].Food Chemistry, 2009, 114(3):905-911.
[18] 张燕, 陈志飞, 赵颂宁, 等.蛋清源抗氧化肽对HEK293细胞氧化应激损伤的抑制作用及机制[J].中国食品学报, 2019, 19(10):11-22.
ZHANG Y, CHEN Z F, ZHAO S N, et al.The anti-oxidative effects and mechanism of antioxidant peptides from egg white against oxidative stress injury in human embryonic kidney 293 cells[J].Journal of Chinese Institute of Food Science and Technology, 2019, 19(10):11-22.
[19] GHOLAMHOSSEINPOUR A, HASHEMI S M B, SAFARI F, et al.Impact of ultrasonicated Lactobacillus delbrueckii subsp.bulgaricus, Streptococcus thermophilus and Lactiplantibacillus plantarum AF1 on the safety and bioactive properties of stirred yoghurt during storage[J].Ultrasonics Sonochemistry, 2024, 102:106726.
[20] GHOLAMHOSSEINPOUR A, HASHEMI S M B.Ultrasound pretreatment of fermented milk containing probiotic Lactobacillus plantarum AF1:Carbohydrate metabolism and antioxidant activity[J].Journal of Food Process Engineering, 2019, 42(1):e12930.
[21] HATMAL M M, NUIRAT A, ZIHLIF M A, et al.Exploring the influence of culture conditions on kefir’s anticancer properties[J].Journal of Dairy Science, 2018, 101(5):3771-3777.
[22] 付丽, 刘旖旎, 陈丹雅, 等.乳清蛋白粉对凝固型酸奶品质的影响[J].食品工业科技, 2020, 41(13):39-45.
FU L, LIU Y N, CHEN D Y, et al.Effect of whey protein powder on the quality of solidified yogurt[J].Science and Technology of Food Industry, 2020, 41(13):39-45.
[23] SARKER A, ALI SIDDIQUI R.Effects of ultrasonic processing on the quality properties of fortified yogurt[J].Ultrasonics Sonochemistry, 2023, 98:106533.
[24] AKDENIZ V, AKALιN A S.Power ultrasound affects physicochemical, rheological and sensory characteristics of probiotic yoghurts[J].International Dairy Journal, 2023, 137:105530.
[25] ZHANG D, PALMER J, TEH K H, et al.Identification and selection of heat-stable protease and lipase-producing psychrotrophic bacteria from fresh and chilled raw milk during up to five days storage[J].LWT, 2020, 134:110165.
[26] JOON R, MISHRA S K, BRAR G S, et al.Instrumental texture and syneresis analysis of yoghurt prepared from goat and cow milk[J].AkiNik Publications, 2017, 6(7):971-974.
[27] JALILZADEH A, HESARI J, PEIGHAMBARDOUST S H, et al.The effect of ultrasound treatment on microbial and physicochemical properties of Iranian ultrafiltered feta-type cheese[J].Journal of Dairy Science, 2018, 101(7):5809-5820.
[28] 田硕, 王晋伟, 孔祥云, 等.挤压处理的麦麸对酸奶品质的影响[J].食品研究与开发, 2024, 45(9):127-133.
TIAN S, WANG J W, KONG X Y, et al.Effect of extruded wheat bran on the quality of yogurt[J].Food Research and Development, 2024, 45(9):127-133.
[29] 李阳, 陈树兴.单、双峰骆驼酸奶品质与风味的比较[J].食品与机械, 2024, 40(5):173-179.
LI Y, CHEN S X.A comparative study on the quality and flavor of dromedary and bifocal camel yogurt[J].Food & Machinery, 2024, 40(5):173-179.
[30] DELGADO K, VIEIRA C, DAMMAK I, et al.Different ultrasound exposure times influence the physicochemical and microbial quality properties in probiotic goat milk yogurt[J].Molecules, 2020, 25(20):4638.
