第八章果蔬汁飲料生產(chǎn)1

1、2022-3-21第八章第八章 食品加工工藝食品加工工藝一、果蔬汁飲料一、果蔬汁飲料2022-3-21第一節(jié)第一節(jié) 果蔬汁飲料的生產(chǎn)果蔬汁飲料的生產(chǎn)輻照保藏的概念輻照保藏的概念以新鮮或冷藏果蔬(也有一些采用干果)為原料，經(jīng)過(guò)清洗、挑選后，采用物理的方法如壓榨、浸提、離心等方法得到的果蔬汁液，稱(chēng)為果蔬汁，因此果蔬汁也有“液體果蔬”之稱(chēng)。以果蔬汁為基料，通過(guò)加糖、酸、香精、色素等調(diào)制的產(chǎn)品，稱(chēng)為果蔬汁飲料。2022-3-21Orange Fruit Processing2022-3-21Commercially Important Orange Varieties Valencia - most

2、widely grown, late maturing, good for FCOJ Pineapple - mid season maturing, good fresh &processing qualities Hamlin - early maturing, beats the freeze Pera - late maturing, most popular in Brazil2022-3-21Fruit Quality Factors Soluble solids Acidity Brix/acid ratio Juice color Low level of bitter com

3、pounds Good flavor2022-3-21Juice Categories Fresh unpasteurized FCOJ Chilled orange juice Canned orange juice2022-3-21Fresh Unpasteurized Juice Minimal treatment after extraction before packaging and distribution Excellent flavor, but shelf life 3 days Must be stored at 10C, preferably cooler2022-3-

4、21Preparation for ProcessingWashingSortingFreshProcessedFungicide/waxExtractor2022-3-21Frozen Concentrated Orange Juice (FCOJ) Developed 1940s Initial product had poor flavor & color Development of high vacuum, low temperature evaporator improved quality Concentrate was added to a small quantity of

5、fresh “cut back” juice to restore flavor & aroma lost during concentration2022-3-21Frozen Concentrated Orange Juice (FCOJ) Original low temperature evaporators have been replaced by: A) multi-effect, multi-stage, high temperature, short time evaporators B) thermally accelerated short time evaporator

6、s (TASTE) Volatile aroma & flavors compounds are collected (aqueous essence or essence oil) 2022-3-21Concentrating JuicesSingle strength juicePulp discharge ascake or slurry for laterreconstitutionClarified serumConcentrated serum for subsequentreconstitutionCentrifuge3-effect thermal evaporator2-ef

7、fect thermal evaporatorHyperfiltrationHyperfiltration1232022-3-21Multiple- (two-) effect evaporatorS1F1V1P1C1F2V2C2P22022-3-21Chilled Orange Juice Fresh juice - pasteurized, either hot filled or aseptically filled after cooling into sterile containers Blending to achieve uniform quality FCOJ - juice

8、 is reconstituted, pasteurized & peel oil added for flavor, then filled into sterile packages2022-3-21Package Considerations Glass - deterioration of color, flavor and loss of ascorbic acid Plastic containers or plastic lined cartons - orange flavor compounds migrate into the plastic container2022-3

9、-21Canned Orange Juice Produced by reconstituting FCOJ or blending juices from several varieties Steps involved: . Deaeration . Deoiling . Pasteurization . Canning2022-3-21Juice Deaeration Reduces levels of dissolved oxygen Reduces flavor deterioration Prevents degradation of ascorbic acid Reduces f

10、rothing during the filling step2022-3-21StrawberryMango, papaya, pineappleGrapefruitBananaOrangeGrape02110515021105 15O2 %CO2%Cherry2022-3-21CO2eCO2iO2iO2ePlastic filmAreaVolumePermeability O2Permeability CO2ThicknessProduceWeightOxygen uptakeCO2 productionThe MAP System2022-3-21FilmGas and water va

11、por permeabilityDiffusionAdsorptionDesorptiongas fluxHigh concentrationLowconcentration2022-3-21O2eCO2eOxygen and carbon dioxide transfer from a fruitO2cO2iCO2i2022-3-21Air inFeed in Product outSpray Drier2022-3-21Post-harvest Handling The objective: To extend the shelf life of fresh horticultural c

12、ommodities. We must understand the biological and environmental factors involved in deterioration. Use Post-harvest technology procedures which will delay senescence and maintain the best possible quality2022-3-21Flow chart for Post-harvest handling operationsHarvestingWashingSortingPackingCoolingStorageTransportation to Retail Stores2022-3-21Flow chart for Fresh-cut processHarvesting