猕猴桃发酵果醋研制

研究了以猕猴桃为原料液态发酵法生产猕猴桃果醋的工艺条件。实验确定了酒精发酵的最佳工艺条件、醋酸发酵的最佳工艺条件。制品既能直接作为调味品,又能调配成果醋饮料。     

水果捞

休闲食品的生产企业应抓住年前市场休闲食品热销的这股势头,将自己的优点亮出,并扩大自己的宣传来吸引更多经销商的注意。而眼下正值新年市场前的储备期,企业应在这时抓住经销商心态,为他们提供一款好的产品同时也要给他们一个丰厚的利润空间,这样他们才能腾出更多的货仓来储存新品。     

Anthocyanin-rich fruit vinegar from Grewia and Cantaloupe fruit blends

Grewia is a tropical berry rich in anthocyanins and antioxidants but highly perishable in nature. In this study, desirable composite blend of overripe Grewia (Phalsa) berries and cantaloupe was sought for conversion to acetic acid. Composition of raw macerate, and the alcoholic and acetic ferments was analysed for sugars, alcohol and acetic acid. The primary alcohol yield varied significantly (5.75–99.44%) with blend composition. Vinegar from select blend attained 4.98% acidity with 138.57 mg mL⁻¹ of phenols and high anthocyanins retention (74.77%). Gompertz model was used to fit the growth curves of S. cerevisiae and A. aceti (R²> 0.92) during fermentation. Presence of ethyl acetate, iso-pentyl alcohols explained pleasant sweet fruity aroma of resulting vinegar. Thus, high quality functional red fruit vinegar can be obtained to prevent spoilage and utilise the functional potential of this delicate and nutritious berry.     

Moulds and yeasts in fruit salads and fruit juices

Thirty-eight fruit salad samples including cantaloupe, citrus fruits, honeydew, pineapple, cut strawberries and mixed fruit salads, and 65 pasteurized fruit juice samples (apple, carrot, grapefruit, grape and orange juices, apple cider, and soy milk) were purchased from local supermarkets in the Washington, DC area and tested for fungal contamination. The majority of fruit salad samples (97%) were contaminated with yeasts at levels ranging from <2.0 to 9.72 log10 of colony forming units per gram (cfu/g). Frequently encountered yeasts were Pichia spp., Candida pulcherrima, C. lambica, C. sake, Rhodotorula spp., and Debaryomyces polymorphus. Low numbers of Penicillium spp. were found in pineapple salads, whereas Cladosporium spp. were present in mixed fruit and cut strawberry salads. Twenty-two per cent of the fruit juice samples tested showed fungal contamination. Yeasts were the predominant contaminants ranging from <1.0 to 6.83 log10 cfu/ml. Yeasts commonly found in fruit juices were C. lambica, C. sake, and Rhodotorula rubra. Geotrichum spp. and low numbers of Penicillium and Fusarium spp. (1.70 and 1.60 log10 cfu/ml, respectively) were present in grapefruit juice.     

全球果汁及果汁饮料消费状况

来自Euromonitor的资料显示,自1992年至2007年,全球果汁及果汁饮料消费市场大多呈现平稳的增长势头.     

欧洲果品市场简况

在欧洲水果制品市场上的产品品种繁多,为不断进入买方市场的水果产品制造商提供了新的商机。由于人们对健康的广泛关注,促进了对新鲜水果制品的消费。一些经过加工的水果,例如     

果酒中有机酸及其对果酒作用的研究

介绍了果酒中主要有机酸的来源及其在发酵过程中的变化,综述了果酒中有机酸的分析检测方法以及有机酸对果酒风味、口感、稳定性等方面的影响,为果酒酿造过程中酸的控制提供了依据,以期达到通过控制酿造过程中有机酸的含量和比例改善并且进一步提高果酒质量之目的。     

黑加仑果与果酒香气成分的GC-MS分析

采用顶空-固相微萃取法(HS-SPME)和气相色谱-质谱联用仪(GC-MS)萃取检测鉴定黑加仑果实和果酒酵母1399酿造的黑加仑果酒芳香物质的成分和含量,对比黑加仑果实和黑加仑果酒的香气成分变化。从果实中鉴定出50种成分,占峰面积的84.22%,香气成分主要为2-甲基-3-丁烯-2-醇、4-甲基-1-戊醇、辛酸乙酯、癸酸乙酯、正戊烯、正辛醛、壬醛、己醛、戊醛等;从果酒中鉴定出48种成分,占峰面积的92.65%,主要香气成分为苯乙醇、3-甲基-1-丁醇、乙酸乙酯、辛酸乙酯、正己酸乙酯、癸酸乙酯、乙酸苯乙酯、苯乙醛等。     

Evaluation of fruit authenticity and determination of the fruit content of fruit products using FT-NIR spectroscopy of cell wall components

An analytical procedure using Fourier transform near infrared (FT-NIR) spectroscopy and chemometrics with multivariate techniques for the rapid determination of the fruit authenticity and for the quantification of the fruit content was developed, based on the cell wall constituents (alcohol-insoluble residue, AIR, and hemicellulose, HC). The contents of rhamnose, fucose, arabinose, xylose, mannose, galactose, and glucose in the hemicellulose fraction of apricots, peaches, and pumpkins determined by gas chromatography were used as references. Furthermore, spectral information was correlated with the fruit content and the gravimetric data obtained from sequential fractionation of the alcohol-insoluble residue. Samples of self-made and commercial apricot and peach fruit preparations, jams, and spreads were included in the investigations. Hemicellulose from 109 samples and AIR from 92 samples was recorded, and principal component regression was used to create calibration models relating chemical and gravimetrical reference values to spectral data. The calibration models provided a good predictability in comparison with the results obtained by reference methods. Good agreement was also obtained for the prediction of the neutral sugar composition of the HC and the fruit content from the AIR. FT-NIR spectroscopy allowed a rapid, accurate and non-destructive assignment of specified fruit from spectral data of the HC fraction and the AIR. Thus, FT-NIR could be applied for investigations on quality control complementing, or even replacing, gas chromatography as the most widespread method for the determination of neutral sugars. Furthermore, preliminary investigation on classification of fruit blends was performed. The probability of belonging to a specific fruit was significantly lowered or precluded for samples with fraudulent admixture like peach or pumpkin to apricot, or pumpkin to peach.     

高效液相色谱法测定浓缩果汁及水果果糖中5-羟甲基糠醛

建立了浓缩苹果汁、浓缩梨汁和水果果糖中的5-羟甲基糠醛的高效液相色谱（HPLC）检测方法。样品用甲醇溶解后,经水稀释,Inetrsil ODS-3 C18（250mm×4．6mm,5μm）色谱柱分离,紫外检测器在282nm处进行检测;5-羟甲基糠醛在1．0-25．0mg／L范围内线性关系良好,相关系数为0．9998,回收率为82．2％～103.3％,精密度（RSD）为0．62％-1．25％,方法的检出限（LOD）为0．2mg／kg。本方法具有快速、简单、灵敏度高、适用范围广等特点,可以满足果汁中5-羟甲基糠醛的分析要求。     

Determination and the hygienic-toxicologic significance of patulin in fruit and fruit products]

The combination of extracting, chromatographic and fluorescence densitometric steps permits to determine patulin in fruits and fruit products with great precision and sensitivity. The limit of detection is 10 microgram/kg; the recovery rates range from 86 to 92% with a variation coefficient lying between 5.6 and 13.6%. Interferences due to patulin-simulating substances are widely excluded. Patulin concentrations ranging from 0.3 to 42 mg/kg were found in the brown-rotten portions of apples. Juices domestically prepared from healthy fruits and fruits rid of rotten portions, respectively, contained no patulin. On the contrary, patulin concentrations ranging from 0.02 to 0.3 mg/l were observed in commercial apple juices. As to products with subsequent mould infection, patulin values up to 50 mg/l were found in apple juices, and up to 0.4 mg/kg in peach preserves. In a further 24 commercial fruit and vegetable juices, patulin was not detectable even not in cider, in cereals which had gone mouldy spontaneously, and in bread samples. The fruits and fruit products were analysed not only for patulin, but also for aflatoxin and ochratoxin; the latter two, however, were found in none of the samples examined. The possibilities of manufacturing patulin-free products are discussed.     

采用夹持果梗方法的水果检测分级机设计

采用夹持水果果梗的方法,设计一套能够适应当前水果在线检测分级需求的水果检测分级机,主要包括水果果梗夹持装置、输送装置、旋转装置以及分级卸果装置。其中果梗夹持装置是本设计的核心部件,它不仅能够独立完成果梗的夹持功能,还能够在其他辅助装置的配合下完成水果的输送、旋转及卸果功能。该果梗夹持装置实现了水果夹持部分与水果的共同旋转,有效避免了水果与机械装置之间的摩擦,使得整个水果检测分级机对水果的机械损伤大大降低,能够很好地满足水果在线检测分级的需求,具有较高参考价值和应用前景。     

冷破碎工艺对猕猴桃果浆品质的影响

以海沃德、华优、红阳三个不同品种的猕猴桃为原料,利用冷破碎专利设备制取猕猴桃果浆。采用化学方法分析其营养特性指标(包括可滴定酸、总糖和还原糖、果胶、蛋白质、维生素C及多酚含量),同时与经传统工艺制取的果浆相比较,探讨冷破碎技术的优劣。实验结果表明,冷破碎工艺使海沃德、华优、红阳猕猴桃果浆酸度分别提高了69.9%、105%、34.2%,多酚及多酚氧化酶含量下降了49.4%、30.5%、43.8%和42.3%、48.3%、51.7%;总糖和还原糖变化不大,果胶、蛋白质含量变化显著。所以,采用冷破碎工艺获得的果浆比较好地保留了猕猴桃原果的营养品质,从防止营养品质劣变的角度看,冷破碎工艺是值得推广应用的果品加工先进技术。      

Texture analysis of Red Delicious fruit: Towards multiple measurements on individual fruit

The sensory texture of Red Delicious apples was studied using single point and time–intensity (TI) methods together with penetrometers and in vivo techniques. Testing was performed in two trials on a per fruit basis, not with fruit batches. The standard penetrometer was significantly correlated (p < 0.05) to sensory hardness, juiciness, mealiness, crunchiness and degree of breakdown, but not to skin toughness. Facial muscle activity during chewing was collected with electromyography (EMG) together with spit outs for individuals. Parameters such as work done during chewing were extracted from the full EMG signals, and some were found to be related significantly (p < 0.05) to the penetrometer data and to sensory hardness. The aspect ratio of expectorated particles related significantly (p < 0.05) to sensory hardness and skin toughness.Principal component analysis shows that 76% of the variance in the combined data set was explained by seven components in Trial 1 and 73% by six components in Trial 2. The first component in both trials was described, principally by hardness, mealiness and the penetrometer value. The second component was described by the EMG signal parameters in Trial 1, and the apple skin properties in Trial 2. Sensory terms hardness, mealiness, crunchiness and juiciness were inter-correlated which may indicate that the texture of Red Delicious apples is perceived as mainly one-dimensional.     

Preservation of oil palm fruit and oil palm fruit mesocarp by gamma irradiation

Experiments were conducted to determine the potential of gamma radiations in the extension of the shelf-life of oil palm fruit and oil palm fruit mesocarp. In the course of the experiment, it was observed that even though palm fruits in their harvested form, went bad within 3 days post-harvest, their shelf-life can be extended to at least 2 months through preparation of dry oil palm fruit mesocarp. Furthermore, despite the fact that gamma radiation cannot be used to prolong the shelf-life of oil palm fruit proper, it can be used to drastically reduce the mould load in the dry palm fruit mesocarps, thereby further enhancing their keeping quality and consumer acceptance. Chemical and organoleptic analyses of fat extracted from irradiated, dry oil palm fruit mesocarp show that there is practically no radiation effect. The significance of these observations is discussed in relation to the possible acceptance of radiation-preservation of oil palm fruit mesocarp commercially.     

Consumer perceptions of novel fruit and familiar fruit: a repertory grid application

To explore how consumers perceive novel and familiar fruit, repertory grid interviews were carried out with 60 New Zealand women. Participants described their perceptions of nine fruit varying in familiarity. The data analysis established a two‐dimensional stimuli space that separated samples with respect to familiarity and the amount of preparation required. Fruit that was familiar was characterised as being well liked, easily available in shops and by a number of different use situations. The primary association with novel fruit was that it was expensive. The participants could not readily think of use situations for fruit they were unfamiliar with. Consumers were separated into groups according to the trait of food neophobia, which pertains to an individual's stable propensity to approach or avoid novel foods. When comparing the most neophobic (n = 14; avoids novel foods) and most neophilic (n = 14; approaches novel foods), individuals perceptual differences were uncovered pertaining to which of the fruit were considered novel and to the suitability of some usage situations (cooking and for children). This finding contributed to the growing evidence of the relationship between food neophobia and consumers' everyday food‐related behaviour. Copyright © 2004 Society of Chemical Industry     

Determination of the fruit content of cherry fruit preparations by gravimetric quantification of hemicellulose

A method recently developed for the determination of the fruit content of strawberry fruit preparations by gravimetric quantification of hemicellulose was extended to cherry fruit preparations. Isolation of the alcohol-insoluble residue (AIR) and sequential fractionation of the cell wall compounds from cherries (Prunus cerasus L. cv. ‘Oblacinska’) was performed yielding the amount of fresh cherries per gram hemicellulose. Cherry fruit preparations with varying fruit contents (30–40%) were produced using different hydrocolloid systems (pectin, starch, guar gum, xanthan gum, carrageenan, and combinations thereof). After separation of the hydrocolloids by enzymatical digestion and successive extraction, the fruit preparations were subjected to AIR isolation. The AIR was fractionated to yield the hemicellulose fraction, which was quantified gravimetrically for the calculation of the fruit content. Compared to strawberries, modifications including additional extraction steps for the sequential fractionation were required to separate the pectin of the cherries exhaustively. Calculated and initial fruit contents were in good agreement for the single hydrocolloid components pectin and starch as well as for the combinations pectin/xanthan gum and pectin/carrageenan (26.8% vs. 30%, 38.6% vs. 40%, 42.5% vs. 40%, 37.6% vs. 40%, and 41.2% vs. 40%), whereas the preparations produced with more complex hydrocolloid systems (pectin/xanthan gum/guar gum and starch/xanthan/guar gum) showed larger deviations in their contents (46.2% vs. 40%, 49.6% vs. 40%). It is concluded that the novel method is generally suitable for the determination of the fruit content of fruit preparations, but steps of sample preparation need to be individually adapted to the different fruit matrices.     

果醋开发意义、工艺研究及果酣类型

概述了果醋开发的意义,果醋开发不仅能充分利用水果资源,节约粮食,而且提供了营养价值高、具保健功效的新型饮品。论述了果醋工艺研究进展,列出了几类发酵方法生产果醋的工艺流程,较系统地总结了果醋类型,并展望了果醋的开发前景。