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The whipped cream dispenser is a foaming tool that is an increasingly applied for on-site whipped cream consumption. It creates foams by incorporating nitrous oxide (N2O) or carbon dioxide (CO2) into protein dispersions, while other foaming methods such as agitation and aeration create foam by incorporating air and nitrogen (N2). In this study, a whipped cream dispenser was used to investigate the effects of different gases and proteins on the foaming properties of protein dispersions. Four gases (CO2, N2O, air, N2) and five proteins were used. The results show that a higher foaming capacity was obtained for all the protein dispersions that were prepared with more soluble gases (N2O and CO2). The foam that was prepared with the more soluble N2O was less stable than that prepared with air and N2. Although the impact of proteins on the foam stability was lower than that of gases, the applying different proteins also significantly changed the foam stability.

Japanese apricot and avocado powders without chemical modification or complicated processing were firstly applied for stabilizing food emulsions containing soybean oil as a source of clean label ingredients. In this work, Japanese apricot and avocado powders as fiber-rich and lipid-rich emulsifiers, respectively, were studied for evaluating emulsifying properties of the fruit powders. Each powder was dispersed in a water or an oil phase, followed by emulsifying with the other immiscible phase to produce emulsions. A more remarkable effect on emulsifying properties was found when fiber-rich powders were dispersed in a water phase and oil-rich powders were dispersed in an oil phase. In addition, avocado powder-based emulsions showed the high stability against creaming (no phase separation) for at least 24 h stored at 4 °C, and both Japanese apricot and avocado powder-based emulsions presented high stability against coalescence for 14-day storage. The results suggested high possibility that fruit powders can be used as food-grade emulsifiers to stabilize emulsions with high physical stability.

The alkaline extract of Enoki mushroom (Flammulina velutipes) has been shown to have ice crystal growth inhibiting activity, and its beneficial effect on the quality preservation of frozen foods is highly expected. The purpose of this study was to investigate the effect of Enoki mushroom extract which has an ice recrystallization inhibiting activity on the quality of frozen whipped creams. Whipping creams with different milk/vegetable fat compositions were prepared. The proportion of % milk fat and % vegetable fat was given as follows; 0:37, 10:28, 20:20 and 40:0, respectively. Whipped foam samples were frozen and stored at −20 °C, then the effect of adding 0.1% Enoki mushroom extract was tested. Fresh dairy flavor and smooth melt in mouth texture was deteriorated during the course of frozen storage for 37 days, and the frequency is higher in whipped creams with high milk fat content. Addition of 0.1% Enoki mushroom extract ameliorated these quality changes and significantly retained moisture content. Microscopic observation of the internal structure of frozen foam samples by cryo-SEM revealed that the ice crystal aggregates grown in the emulsified solid phase were reduced by adding Enoki mushroom extract. GC/MS analysis of the flavor components revealed that the content of furan compounds (furfural and 2-furanmethanol) was increased by 1.7 times in control foam samples during frozen storage, whereas the furan compounds in whipped foam sample containing Enoki mushroom extract did not increase after frozen storage. Based on these findings, it is proposed that ice crystal growth at the emulsified solid phase causes the sublimation of water on the surface of frozen whipped cream and destruction of the network structure of fat globules results in the quality changes after thawing. Enoki mushroom extract was found to retard ice crystal growth in whipped cream, thus supposed to reduce the quality changes during frozen storage.

For milk-based emulsion products such as canned coffee or tea, the addition of bacteriostatic emulsifiers is necessary to inhibiting the growth of heat-resistant sporeformers. Since bacteriostatic emulsifiers often cause the destabilization of emulsions, other type of emulsifiers, such as stability-enhancing ones, are necessary for the long-term stability of emulsions. Four milk-based emulsions were prepared from powdered milk combined with several types of emulsifiers. The long-term stability of emulsions, which was detected by the occurrence of a creaming layer after 3 months of storage, differed according to the composition of emulsifiers. To understand the reason for the differences in the stability of emulsions, particle size, distribution, ζ-potential, and the amount of proteins and phospholipids present in the cream layer (separated oil droplets) in the emulsions were measured. Only the amount of proteins adsorbed onto oil droplets was found to be closely related to the difference in emulsion stability, that is, the more proteins adsorbed, the higher the emulsion stability. SDS–PAGE analyses revealed that κ-casein and β-lactoglobulin play an important role in emulsion stability by adsorbing onto the oil droplet surface.