Milk is an important food substance and has a complex polydisperse system. The main components of milk consist of lactose, protein, and lipids. Mineral substances and vitamins are also present in milk as minor nutrients. Lactose known as milk sugar is the only carbohydrate in milk and it consists of glucose and galactose. The content of lactose in milk has varied according to milk types. Moreover, it is the most important energy source during the first years of human life, providing almost half of the total energy needed by newborns. Lactose is obtained industrially from the residues of cheese and casein production processes. Lactulose, lactitol, lactobionic acid, galactooligosaccharide, lactosucrose, epilactose, and tagatose are commonly known lactose derivatives. These derivates are produced from lactose using various methods such as epimerization, oxidation, and reduction. In this review, up-to-date information about lactose, lactose derivatives, and the production methods of lactose derivatives are given.

The aim of this study was to evaluate the dough proofing activity of Kluyveromyces lactis (ATCC 8585) in different dough formulations and to compare it with the commercial active dry bakery yeast Saccharomyces cerevisiae. Leaving ability of yeasts was tested in lean and rich dough. For both cultures, lean and rich dough mixtures containing 0.3 g of yeast biomass (on dry weight basis) and wheat flour in 15 ml of water was prepared. Rich dough contained also either 2.0 g of sucrose, 2.0 g of lactose or 2.5 g of whey powder. Dough mixtures were incubated at 29°C and volume increase was recorded every 15 min. We determined that Kluyveromyces lactis had higher volume and leavening rates compared to commercial bakery yeast strain in lactose-rich or whey-rich dough. These results demonstrated the potential of Kluyveromyces lactis yeast strain as a suitable culture for whey fortified bread making.

The aim of this study was to evaluate the dough proofing activity of Kluyveromyces lactis (ATCC 8585) in different dough formulations and to compare it with the commercial active dry bakery yeast Saccharomyces cerevisiae. Leaving ability of yeasts was tested in lean and rich dough. For both cultures, lean and rich dough mixtures containing 0.3 g of yeast biomass (on dry weight basis) and wheat flour in 15 ml of water was prepared. Rich dough contained also either 2.0 g of sucrose, 2.0 g of lactose or 2.5 g of whey powder. Dough mixtures were incubated at 29°C and volume increase was recorded every 15 min. We determined that Kluyveromyces lactis had higher volume and leavening rates compared to commercial bakery yeast strain in lactose-rich or whey-rich dough. These results demonstrated the potential of Kluyveromyces lactis yeast strain as a suitable culture for whey fortified bread making.

South Anatolian Red (SAR) and Native Southern Yellow (NSY) cattle are commonly reared in the southern region of Turkey. Although physical characteristics of these significant races that are under protection are similar, it is determined in various studies that they have different racial characteristics. The goal of this study is to evaluate lactation characteristics of two different breeds in the same region. It is observed that NSY milk has higher dry matter (%), fat (%), protein (%), lactose (%), total saturated and unsaturated fatty acids (g 100g-1) ratios than SAR milk. In the study, eight volatiles (indoles, ketones, terpenes, aromatic hydrocarbons, esters, carboxylic acids, aldehydes, alcohols) of the cattle types are researched and analyzed and they are compared during lactation periods. At the end of lactation, esters and carboxylic acids increased in NSY milk, while ketones and aldehydes in SAR milk increased. It is seen that alcohols are the most abundant volatile components found in milk of cattle. On the other hand, it is observed that lactation stages, forage type and botanical diversity affect milk flavor and quality.