Cashew Apple Juice as Substrate for Lactic Acid Production

The aim of the present work was to investigate the use of cashew apple juice as a low cost substrate for Lactobacillus casei B-442 cultivation and lactic acid production. Ammonium sulfate was employed as the only exogenous nitrogen source. The effect of cashew apple juice reducing sugars and ammonium sulfate concentration and the fermentation pH and temperature on biomass formation, lactic acid production, and productivity were evaluated. The highest productivity (2.36 g/L.h) was obtained applying 50 g/L of reducing sugar from the cashew apple juice supplemented with 6 g/L of ammonium sulfate. The process yield was about 95% when fermentation was carried out at 37 °C with pH controlled at pH 6.5 using NaOH (120 g/L).     

Investigation of Cashew Apple Juice as a Substrate for Single Cell Protein Production

Cashew juice was investigated for its ability to support the growth of Saccharomyces cerevisiae. A characteristic of the juice showed that it contained a mixture of fermentable sugars of which glucose, fructose and sucrose have been identified. Also the concentration of reducing sugars was as high as 15% w/v. Growth studies were carried out in a 7-L batch fermentor at a pH of 5.0 and 30°C with and without nutrient supplementation. The corresponding yields were 0.50 and 0.39 gram cells/gram reducing sugar consumed, respectively. While about 10% of the reducing sugar was consumed in the unsupplemented medium 43% was consumed in the medium with supplementation.     

Spray-Drying of Probiotic Cashew Apple Juice

Data on spray-drying of fruit juices containing probiotic bacteria are scarce. The main challenge is to avoid the viability losses of the microorganism during drying and storage. In the presented study, the dehydration by spray-drying of cashew apple juice containing Lactobacillus casei NRRL B-442, and the influence of the storage temperature (25 and 4 °C) on the viability of L. casei NRRL B-442 and on the physical properties of the powder during 35 days of storage were evaluated. Probiotic cashew apple juice was dehydrated according to the following conditions: inlet temperature of the drying air (120 °C), feed flow rate of juice (0.3 L/h), hot air flow (3.0 m³/min), and pressurized air flow (30 L/min). The outlet temperature was 75 °C. The carriers used were 20 % (w/v) maltodextrin or 10 % (w/v) maltodextrin + 10 % (w/v) gum arabic. Microbial survival rates higher than 90 % were obtained for the powder stored at 4 °C for 35 days (both carriers) and higher than 70 % up to 21 days for the powder obtained using only maltodextrin at 25 °C. Higher yields were obtained only by maltodextrin which was used as carrier (72 %) compared to the yield obtained when the mixture of maltodextrin and gum arabic was applied (60 %). The water activity was kept low (Aw?<?0.30) during the storage, and the characteristic color of the product was maintained.     

Dextransucrase Stability in Cashew Apple Juice

The use of agriculture waste as substrate for biotechnological process became an interesting alternative to reduce production costs and the negative impact of agricultural wastes disposal in the environment. In Brazil, cashew tree cultivation is done aiming the cashew nut production, and tons of cashew apples are wasted in the field after the nut removal. Thus, cashew apple juice can be used as low cost substrate for biotechnological process. In this study, the stability of dextransucrase produced in a fermentation medium using cashew apple juice as substrate was evaluated. The crude enzyme was stable at 30 °C for 30 h at pH ranging from 4.5 to 5.5. The partially purified enzyme was stable in non-fermented cashew apple juice at pH 5.0 for 96 h at 30 °C. The high stability of the enzyme in cashew apple juice at room temperature allows its industrial use without needing the enzyme purification, consequently reducing process costs.     

Storage Stability and Acceptance of Probiotic Beverage from Cashew Apple Juice

The stability of nonfermented cashew apple juice (control) and the fermented juice with Lactobacillus casei NRRL B-442 (sweetened and nonsweetened samples) was investigated along the storage at 4 °C for 42 days. The viability of the probiotic bacteria, sugars, lactic acid, and vitamin C content besides color, antioxidant activity, enzyme activity, and sensory characteristics of probiotic cashew apple juice was evaluated. It was observed that viable cell counts increased in the probiotic cashew apple containing sucrose (8 % w/v) along the storage period. Viable cell counts were always higher than 8.00 Log CFU/ml throughout the storage period. Ascorbic acid loss was higher in the nonfermented juice (40 %) compared to the fermented juice (23 %). The same behavior was observed for antioxidant activity and total polyphenolic compounds content, conferring nutritional benefits to this functional food. Browning reactions and nutritional breakdown caused by enzymes were minimized in the fermented samples during storage. In the fermented sample, higher reduction (>70 %) in the polyphenol oxidase enzyme activity was observed. During storage, the increase in the chroma values from 3.2 to 5.0 indicated that the yellow color became more vivid. Sensory analysis of the fermented cashew apple juice revealed that the product was well-accepted, with acceptance percentages above 80 % for the sweetened juice at the end of the storage period.     

复合乳酸菌发酵西瓜-番茄果蔬汁的工艺优化

本研究以自主分离筛选的植物乳杆菌S3-10和干酪乳杆菌R10作为发酵菌株,通过单因素和正交实验探讨了菌种配比、果蔬汁含量、蔗糖含量、葡萄糖含量、温度等参数对西瓜-番茄果蔬发酵的影响。结果表明,2株乳酸菌复合发酵西瓜-番茄果蔬汁的最佳工艺参数为:S3-10和R10菌株配比1:2、果蔬汁44.4%、蔗糖5%、葡萄糖6%、发酵温度40℃,在此条件下获得的活菌数为4.79×108cfu/m L,总产酸量为12.42g/L,比初始总酸含量提高21%。通过HPLC法对乳酸菌发酵过程中的有机酸进行分析,发现2株乳酸菌单独发酵或复合发酵西瓜-番茄过程中有机酸的种类及变化相似,2株乳酸菌复合发酵产乳酸和总酸含量明显高于单一菌株发酵。综合考虑乳酸菌S3-10和R10复合发酵西瓜-番茄性能优异,在开发果蔬发酵产品及其他功能益生产品方面具有较大潜力和应用前景。     

气相色谱-质谱法分析乳酸菌发酵苹果汁香气成分

以乳酸菌单一菌种和多菌组合分别发酵苹果汁,采用紫外-可见分光光度计测定发酵过程中苹果汁光密度(optical density,OD)的变化,采用顶空固相微萃取和气相色谱-质谱联用技术检测9组发酵苹果汁的香气成分,结合不同香气物质的阈值与香气值分析特征香气成分,并对各组苹果汁进行感官评价。结果表明:在发酵过程中苹果汁的OD值呈对数上升趋势。各组苹果汁中共鉴定出48种香气成分,主要包含醇类、酯类、醛类、酮类和酚类,其中酯类是各发酵组中种类最多且含量最大的香气类别,其次是醇类。9组苹果汁的主要香气成分和香气值较大并有突出贡献的特征香气成分均为丁酸乙酯、2-甲基丁酸乙酯、2-甲基丁基乙酸酯和乙酸己酯等。多菌发酵和单菌发酵苹果汁的香气成分含量及香气值差异显著(P0.05),说明多菌发酵中醇类、酯类和其他类香气物质的总含量明显高于单菌发酵,且赋予苹果汁更强烈的果香、青香和花香。多菌发酵组的总体感官评分高于单菌发酵组,当副干酪乳杆菌20241、动物双歧杆菌6165、嗜热链球菌6063、嗜酸乳杆菌6005活菌数比为1∶1∶1∶1时,感官评分最优。研究结果为今后乳酸菌在发酵果蔬汁方面的研究和应用提供理论依据。     

Modeling of Apple Juice Filtrations

In cake filtration of apple juice, usage of filter aid increased filtration rates. Precoating the filter medium with diatomaceous earth increased filter medium resistance, but cloudy juice was produced in its absence. There was an inverse relation between filtration rates and resistances. Although these were expected results, they did not agree with most of the present filtration theories. De La Garza and Boulton's “exponential model” of wine filtrations simulated the data satisfactorily. Our results show that the common filtration theories, adapted from the other disciplines, may not be appropriate for food engineering analysis.     

发酵沙棘原果汁的乳酸菌筛选及工艺优化

该研究以沙棘原果汁为原料,利用乳酸菌进行发酵,筛选出转化黄酮苷元含量高的菌株以及发酵工艺。以发酵后的黄酮苷元含量（以异鼠李素计）的变化为筛选标准,先利用26株单菌进行筛选,再进行复配,得到植物乳植物杆菌L23、戊糖片球菌P27和植物乳植物杆菌L21复配效果最好。并利用正交试验对pH值、温度、碳源添加量以及接种比例进行发酵工艺条件的优化。优化后得到的3株乳酸菌在pH值为4,温度30 ℃,添加碳源6%（m/V）,接菌比例为1:2:1时发酵得到的黄酮苷元含量较高,同时检测沙棘原果汁发酵前后总黄酮、总酚酸、有机酸以及粗多糖含量。发酵后的黄酮苷元含量提升约90%,总黄酮提升约108%,粗多糖、有机酸和总酚酸含量与沙棘原果汁相比,具有显著性差异。该研究得出3株乳酸菌发酵沙棘黄酮,黄酮苷元含量明显提升,其他基本指标的含量显著增加,为研究黄酮苷转化为黄酮苷元的机制提供数据参考,为中国沙棘工业产业化深加工提供指导。     

Optimization and Modeling of Apple Juice Cross-flow Microfiltration with a Ceramic Membrane

The performance of a 0.2 μm ceramic membrane for clarification of depectinized apple juice was studied. The results showed that the flux was higher at high feed velocities (14.6 m/seC) and high temperatures (50°C), and the transmembrane pressure was a positive factor only at high temperatures. The juice flux at optimal conditions was between 400–500 kg/hr.m². Filtration of juice with pectin resulted in flux decreases of 40–50% compared to deoectinized juice. Periodic back-flushing during processing at optimal conditions, i.e., high temperature, high feed velocity and low pressure, did not significantly increase the juice flux.     

Optimization of Apple Juice Production by Single Pass Metallic Membrane Ultrafiltration

Apple puree was treated with various amounts of commercial liquefaction enzyme (0%– 0.066%) for 2 hr at 50°C. To produce clarified juice purees were pumped through a metallic oxide membrane ultrafiltration system, consisting of 3.27 ft² (0.304 m²) of membrane coated internally onto a l–1/4 inch (i.d.) × 10 ft (3.12 cm × 3.04 m) sintered stainless steel tubing. All enzyme treatments reduced viscosity 70–80% within 1 hr but steady state flux increased with higher concentrations of enzyme. Alcohol insoluble solids (AIS) and total pectins of the apple puree after enzyme treatment decreased as enzyme concentration increased to 0.044%. A large scale system, l–1/4 inch (i.d.) × 120 ft (3.12 cm × 36.48 m), was operated at 86% juice yield with minimal pressure drops as predicted by a mathematical model.     

乳酸及其代谢工程生产

乳酸是一种具有重要工业价值的有机酸。在体内,乳酸不仅是一种能源物质,而且可能作为一种信号分子,对维持机体代谢网络的平衡起到了重要作用。本文分析了目前乳酸生产存在的主要问题,介绍了近年来应用代谢工程改进乳酸生产的一些实践,并展望了代谢工程用于乳酸生产的潜能及发展趋势。     

乳酸菌发酵芦笋汁

乳酸菌发酵芦笋汁最佳工艺组合为:芦笋汁中加入10%蔗糖,接种量10%,发酵温度35℃,发酵时间20 h。将蔗糖、葡萄糖、麦芽糖、甘油、可溶性淀粉、玉米粉作为添加碳源时,对pH均有不同程度影响,蔗糖对其pH影响最显著;乳酸菌接种量是影响pH的重要参数之一,接种量较低时,菌体在发酵过程中生长较慢,但接种量过大时也不利于后期次级代谢产物合成;发酵温度是影响发酵成败的关键因素,温度过低或过高乳酸菌生长受到限制。     

乳酸菌发酵鸭梨汁工艺优化及风味研究

以鸭梨为原料,自选戊糖片球菌和乳双歧杆菌HN019按体积比1∶1混合作为发酵剂制得发酵鸭梨汁,为鸭梨深加工开辟新途径.在单因素试验基础上进行Box-Behnken响应面优化试验,以产品含酸量和超氧化物歧化酶(superoxide dismutase,SOD)酶活力为响应值,对发酵工艺条件进行优化.结果表明:接种量3.5...     

苹果浊汁加工中果实成熟度的选择

以生理成熟和完全成熟 2种成熟度的苹果为原料制取浊汁 ,对苹果汁的褐变情况、苹果汁PPO酶的热失活条件、浊汁理化性状以及悬浮稳定性进行比较 ,试验结果表明 :完全成熟的苹果更适宜用作制取浊汁的原料。文中还就苹果果肉细胞的微观形态、影响悬浮稳定性的因素进行了探讨 ,以深入探究完全成熟的苹果更加适宜制取浊汁的机理。     

黄秋葵汁乳酸菌混菌发酵条件优化

为制备风味优良的乳酸发酵黄秋葵汁,研究了肠膜明串珠菌和植物乳杆菌以不同组合在发酵黄秋葵汁中的生长、产酸、感官品质以及挥发性风味成分。结果表明：植物乳杆菌单菌发酵黄秋葵汁可以在24 h内将pH值降到4.5以下,活菌数可达107 CFU/mL。肠膜明串珠菌单菌发酵黄秋葵汁无法顺利产酸。肠膜明串珠菌和植物乳杆菌以其菌液体积比2∶1混合发酵黄秋葵汁,可迅速将pH值降到4.5以下,活菌数可达108 CFU/mL,且感官品质优于植物乳杆菌单菌发酵。气相色谱-质谱联用方法分析可知,混菌发酵生成的挥发性成分比植物乳杆菌单菌发酵种类更多、含量更高。黄秋葵汁乳酸发酵最佳工艺条件为：肠膜明串珠菌和植物乳杆菌菌液以2∶1比例混合、接种量5%、发酵温度35 ℃、发酵时间72 h。     

Clarified Natural Apple Juice: Production and Storage Stability of Juice and Concentrate

Thermal treatment (90°C, 20 sec) of Red Delicious apple mashes followed by Pectinase (0.02%;v/w), centrifugation, bentoniting and filtration resulted in a clear natural apple juice. Whole apple mash juice was faintly pink due to extracted skin anthocyanins and the 70° Brix concentrate prepared from the juice was ruby red. Pink juice browned extensively over 648 hr storage at 37°C and browning was associated with development of an absorption maximum at 446 nm. The ruby red concentrate stored at 37°C, turned orange (167 hr) darkening to brown (648 hr) and gave visible spectral scan typical of Maillard browning development.     

复合乳酸菌发酵枸杞汁的工艺优化

以枸杞干果为主要原料,研究了肠膜明串珠菌(Leuconostoc mesenteroides)和植物乳杆菌(Lactobacillus plantarum)作为复合乳酸菌发酵剂对枸杞汁品质的影响,并采用响应面法对枸杞汁的发酵工艺进行优化,旨在开发一种富含功能因子的发酵枸杞汁,以提高枸杞产品的多样性。通过对发酵过程中pH、可溶性固形物、乳酸、蛋白质、总黄酮、总糖与乳酸菌菌落总数含量及感官指标进行测定分析,以乳酸含量和感官评分为评价指标,探讨发酵过程中枸杞汁品质的变化规律。结果表明,复合乳酸菌最佳发酵工艺条件为:肠膜明串珠菌:植物乳杆菌1:1,接种量5%,白砂糖加量5%,发酵时间10 h。其发酵枸杞汁pH4.01、可溶性固形物8%、乳酸342 mg/100 mL、蛋白质20 μg/100 mL、总黄酮410 mg/100 mL、总糖124 mg/100 mL、乳酸菌菌落总数2.1×10⁸ CFU/mL,感官评分92.01分。所得复合乳酸菌枸杞汁发酵饮品组织均匀、口感细腻、酸甜适中、具有枸杞特有的滋味和芳香。     

混浊苹果汁生产工艺改进的研究

考察了苹果破碎时果浆所达到的最高温度对果汁的颜色、Vc、酚类物质、色泽和混浊稳定性等的影响,确定破碎温度为95℃。热处理增加了果胶的聚合度,促进果胶从果浆中释放,从而增加了果汁的黏度。热处理还可减小果汁中悬浮颗粒的尺寸。用新工艺生产出的产品有较高的浊度和较好的颜色。     

试论如何做好我国小型食品加工企业的销售工作

在我国市场经济日益发展的今天,销售环节成为企业的生命线,尤其对于小型食品加工业（特别说明,是指自产自销的小型食品加工业）,市场形势相对更为严峻。如何把企业的产品尽快地销售出去,销售策略制定的是否正确,决定了企业的经济效益和发展能力,也决定了企业是否能够生存下去。正像马克思所说：“商品的出售,是商品所有者最惊险的跳跃。”在我国,十一届三中全会以前,那种只承认计划经济而不承认商品经济的经济条件下．企业是感觉不到这种“跳跃”的“惊险”性的。应该承认,伴随着商品经济的日益发展,这种“惊险”性越来越增加了,有人说企业的发展取决于消费者的“货币投票”,如何让消费者投你的票是每个企业必须下一凡功夫思考的问题