The aim of this study was to incorporate astaxanthin to yogurts with different fat content to match apricot (Prunus armeniaca L.) color. The samples containing astaxanthin were stored at 5 ± 3 °C, and color stability and astaxanthin content were determined by colorimetry and high performance liquid chromatography (HPLC), respectively. Yogurt samples were analyzed in triplicate every 24 hours for one week and subsequently every week for 3 more weeks There were no significant differences (p < 0.05) between astaxanthin concentration values at 0 and 28 days for both samples; therefore, it can be said that the fat content in the yogurt had not effect on the stability of pigment. The low dispersion of the data showed uniformity in the three chromaticity coordinates L*, a*, b* throughout the storage period for both types of yogurt. Values of ∆E ≥ 5.0 were not obtained at any time during storage, indicating high stability of the pigment.

The goal of the present work was to produce lactic silage from food wastes. A factorial 2³ experimental design was applied using the following factors and levels: yogurt inoculum concentration (1 and 15%), sucrose (2 and 15%) and temperature (22 and 35 ºC) and as response variable, the soluble nitrogen content (SNC) at the end of the fermentation was considered. The best SNC output was for the treatment with 1 % of inoculum, 2 % of sucrose and temperature of 22ºC. The increase of SNC with regards to its initial content, from 0.17 % to 1.67 % for protein contents (PC) < 5 % corresponded to 882 % and from 0.65 % to 2.36 % for PC > 5 % represented 263 %. It was possible to produce a lactic silage and keep it stable for up to 30 days, which was enough storage time before being sent to a drying process for future use in animal feeding or compost.