刺梨火棘混合果汁饮料的加工工艺

本文介绍了刺梨、火棘果实的取汁方法以及刺梨、火棘混合果汁的配比和制作方法。     

变温发酵法生产双歧杆菌大豆酸奶的研究

根据乳酸菌和双歧杆菌的最适发酵温度存在差异的特点,进行变温发酵试验,生产双歧杆菌大豆酸奶.采用正交试验优化配方及发酵工艺条件,并测定其双歧杆菌活菌数.试验结果表明,在40℃下发酵4 h,然后降温到37℃发酵2.5 h,主发酵完成后在4℃条件下后发酵24 h.最终产品双歧杆菌活菌数达107个/mL,较同一配方恒温发酵产品增加了100倍.     

双歧杆菌发酵胡萝卜汁酸乳贮藏稳定性研究

从健康人体中选育出2株发酵活力高、耐氧性和抗逆性强的双歧杆菌优良发酵菌株两歧双歧杆菌Bbm和长双歧杆菌Blm作为试验菌株,制备了双歧杆菌纯种及双歧杆菌与乳酸菌混种发酵胡萝卜汁酸乳,考察了发酵产品在室温(20~30℃)和冷藏(0~4℃)条件下的贮藏稳定性。试验结果表明:0~4℃冷藏21d,活菌含量仍可达1×109cfu/mL以上,pH值降至4.2~4.3,酸甜适宜。因此,确定发酵产品0~4℃下贮藏期为21d。     

新型功能性红曲调味品的研究

本研究以红曲霉，米曲霉为菌种，用不同配比的大米，豆粕，麸皮等为原料，分别进行单菌种及混合菌种培养，培养成熟后，并对其进行发酵，结果表明：可用大米，豆粕为原料培养红曲，米豆比例1．5：1，温度30℃，培养时间6d时为最佳。以红曲霉，米曲霉混合菌种培养，原料以米：豆粕：麸皮比例为1：2：1，温度30℃，培养时间3d为最佳。通过对两种发酵比较：混合菌种培养发酵工艺酿制的新型调味品，在感官及理化指标等方面均优于单菌种培养混合发酵工艺所酿制的调味品。℃     

近红外光谱法测定混合汁中还原糖含量

采用近红外光谱法测定混合汁中还原糖含量 ,获得良好效果 ,所建模型标准误差小而决定系数高。定标决定系数 R2 、交互定标标准误差 (SECV)、交互定标决定系数 (1-VR)分别为 0 .95 1,0 .0 74 ,0 .85 0 ,具有较好的相关性。用 5 2个随机混合汁样品检验该模型 ,近红外法预测结果与传统滴定法测定结果的检验工作标准误差 (SEP(C) )为 0 .0 75 ,检验决定系数 RSQ为 0 .85 0 ,证明测定所建近红外法定标模型具有较好的稳定性。     

影响丙酸菌生长和产酸因素的初步研究

研究了培养方式和各种培养条件对丙酸杆菌的生长、丙酸生物量及环境酸度变化的影响,初步确定丙酸杆菌发酵的初步优化培养方式、培养基的始初pH及不同浓度的营养成分对丙酸杆菌的生长和产酸量的影响,初步优化的培养基成分为葡萄糖3.0%,酵母膏2.0%,蛋白胨0.3%,氯化钴6ppm;培养方式静置有氧培养好;灭菌前pH7.0~7.5。     

Strain-hardening properties of physical weak gels of biopolymers

Weak gels of biopolymers are frequently used in food applications. Dynamic rheological measurements, performed at low strain in the linear domain are useful to characterize the network properties, e.g. gelation, ageing and mechanical recovery after shearing. However, the rupture properties of these gels are also of great interest to complete their characterization.Several weak gels containing carrageenan, xanthan–locust bean gum, pectin or alginate–pectin were investigated. The behaviour of these gels under large strain was studied either in dynamic mode or under constant low shear rate conditions. In many cases, a strain-hardening behaviour was observed: above the upper limit of the linear domain, the stress increased more than proportionally to the strain. A good agreement in stress–strain variations was observed between the results from dynamic and constant shear rate modes.This hardening effect, generally associated with a large deformability, gave to these gels a large resistance to rupture, with regards to their modulus. This can be related to the functionality of the biopolymer systems in terms of texture or suspension properties. As an example, in fluid gels, it allows the suspension of particles with a very weak network (typically a modulus of 1 Pa).     

The effect of multiple yeasts co-inoculations on Sauvignon Blanc wine aroma composition,sensory properties and consumer preference

Consumer acceptance testing has been only recently applied in wine research, to assess wine sensory attributes that affect hedonic liking. The aim of this study was to investigate the effect of Saccharomyces yeast co-inoculations on wine volatile composition and sensory profiles, and to determine if differences were sufficient enough to affect consumer acceptance. Fermentations were conducted using two- and three-yeast co-inoculations, and single strains. Yeast inocula differed substantially in volatile thiols and other flavour compounds, and in their sensory properties. Wines from four yeast inocula which showed large sensory differences were subjected to consumer testing by 120 consumers, with differences in overall liking found. Four clusters of consumers were identified, with one group strongly preferring the two-yeast co-inoculated wine with an intermediate sensory profile, while another group favoured the wine made using the three-yeast co-inoculation. This study has demonstrated that the yeast inoculum used to conduct fermentation affects consumer acceptance.     

莲藕、茅根、菊花复合清凉饮料的研制

研究了莲藕、茅根、菊花复合饮料的制作过程,并对生产工艺技术进行了探讨。     

Gelled vegetable desserts containing pea protein, κ-carrageenan and starch

Due to recent animal diseases, cholesterol intake worries and strong demand for healthy food, there is a greater pressure for the direct consumption of vegetable proteins in food products. In this work, the objective is to develop alternative of strictly vegetable origin desserts based on gelled systems with required physical structure and perceived texture. For this reason, it is important to control the properties of the biopolymer mixtures and understand the phase separation behaviour under different physicochemical conditions. The firmness and storage modulus of different formulations of pea protein/κ-carrageenan/starch systems processed and cooled at different conditions are compared with those parameters obtained for commercial products. Formulation and thermal conditions were determined to influence the texture and storage modulus of the mixed systems. Confocal microscopic images showed that phase separation between pea protein and κ-carrageenan takes place, leading to the formation of two network systems. The binding of water effect, of the starch swollen granules, promotes the concentration of pea protein and κ-carrageenan, reinforcing the gel structure.