Effect of processing and accelerated storage on the volatile composition and sensory profile of a tomato soup

The volatile and sensory profile of pasteurized(95℃,18 min)and sterilized(120℃,14 min)tomato soup and its changes at accelerated storage conditions(37℃and 42℃)were identified,characterized,and correlated by predictive models.Sterilization led to more profound changes over storage compared to pasteurisation,showing enhanced levels of‘dark'odour,‘burnt'flavour,and‘complexity',while pasteurized soup had more pronounced‘green'odour,‘vegetables'flavour,‘harmony',and‘freshness'.Over time,‘dark'and‘burnt'significantly increased for sterilized soups,whereas‘green'decreased significantly only for sterilized soup stored at 42℃.The changes of‘dark',‘green',‘off-flavour,‘burnt',‘har mony',and‘freshness'were associated with formation of furans(furfural and 2-acetyl-5-methylfuran),and decline of unsaturated aldehydes like E-2-octenal and E,E-2,4-heptadienal.These compounds were identified to represent potential shelf-life markers,yet more studies on their odour activity in the tomato soup matrix are necessary to understand their contribution to the sensory quality.The construction of partial least squares models allowed the prediction of‘green',‘off-flavour',‘burnt',and‘freshness'based on selected volatiles.These models will be important tools in the process of predicting the end of shelf life,but need to be supplemented with consumer acceptability levels.

Evaluation of probiotic yoghurt by the mixed culture with Lactobacillus plantarum A3

Lactic acid bacteria(LAB)fermentation is the simplest and safest way of food preservation,and the use of probiotics in yoghurt could provide dairy products with unique flavors,textures and health benefits.In this study,Lactobacillus bulgaricus,Streptococcus thermophilus,L.reuteri DSMZ 8533 and the potential probiotic strain L.plantarum A3 were used for the milk fermentation.Results found the texture properties such as hardness,consistency,and viscosity of the yoghurt were enhanced in the mixed culture condition.Furthermore,components like amino acid(leucine),vanilla(vanillin),C;(unsaturated fatty acids)were also accumulated in L.plantarum A3 fermented yoghut,which leads to the significant sensory profiling difference compared with the former plain yoghurt.All these results proved L.plantarum A3 is a potential probiotic stom winch could enhance the sensory and nutrition profiling of the fermented milk.Future work still needs to be done on the synergistic interaction between the traditional strains and the probiotics during the fermentation process.

Comparison of Physicochemical,Organoleptic and Nutritional Abilities of Eight Sweet Potato(Ipomoea batatas)Varieties

In Martinique (F.W.I.), biodiversity of vegetable varieties remain unexploited due to public unawareness or supply problems. To further enhance the sweet potato, physicochemical, sensory and nutritional characteristics of eight varieties of sweet potato were established. The eight sweet potatoes cultivars were noticeably diverse with phenotypic, sensory, physicochemical and nutritional characteristics which were very varied. The eight cultivars grown in Martinique were advantageously positioned in relation to the globally identified sweet potato, regarding fibre, starch, potassium, copper, vitamin B1, B3 and B9 contents. Compared to the ordinary potato, Martiniquan sweet potatoes have a much better nutritional potential. Energy value and vitamin C levels were twice as much as in normal potatoes. Martiniquan sweet potatoes cultivars were also richer in minerals and vitamins, with 2.7 times more vitamin B9 and 63 times more beta-carotene than the ordinary potato.