Heat treatment of cream affects the physicochemical properties of sweet buttermilk

Abstract

-The objective of this work was to investigate the effect of heat treatment of sweet creams on the physicochemical properties of sweet industrial buttermilks. Creams with three different heat treatments: low, medium and high, were churned and the corresponding buttermilks were characterised. Furthermore, buttermilks were renneted and centrifuged to obtain insoluble pellets and supernatants. The physicochemical properties such as the particle size measured by laser light scattering and composition of creams, buttermilks, pellets and supernatants were determined and compared. Buttermilk had a composition close to that of skim milk but it contained more phospholipids (PL): 958 (± 137) mg·kg −1 , compared with 120 mg·kg −1 in milk. The heat treatment induced a significant decrease in soluble protein contents in creams, buttermilks and soluble fractions as well as an increase in the buttermilk PL/fat ratio, and an increase in supernatant protein and total solids. Buttermilk and supernatant particle sizes ranged from 0.03 to 200 μm, with a maximum at 130 nm, which may correspond to small milk fat globules, phospholipid vesicles or protein aggregates. Fat and PL in buttermilks were recovered in supernatants. The use of buttermilk enzymatic coagulation combined with centrifugation may constitute a means to fractionate milk PL.buttermilk / phospholipid / protein / heat treatment / particle size crèmes, babeurres, sérums et culots, ainsi que la taille des particules ont été déterminées et comparées. L'augmentation de l'intensité des traitements thermiques conduit à une diminution significative de la concentration en protéines solubles dans les crèmes, babeurres et surnageants, à une augmentation du ratio phospholipides/matière grasse du babeurre, ainsi que de l'extrait sec et de la matière azotée totale des surnageants. Les babeurres avaient des compositions proches de celle du lait écrémé, mais avec une concentration plus importante en phospholipides : 958 (± 137) mg·kg −1 contre 120 mg·kg −1 . Les particules des babeurres et des surnageants avaient un diamètre compris entre 0,03 et 200 μm avec un maximum centré sur 130 nm. Ces particules pourraient correspondre à des globules gras de petite taille, des vésicules de phospholipides et/ou des agrégats de protéines. La totalité des lipides contenus dans les babeurres a été retrouvée dans la fraction soluble des surnageants. Techniquement, une coagulation enzymatique du babeurre suivie d'une centrifugation pourrait constituer un moyen de fractionnement des phospholipides.babeurre / phospholipide / protéine / traitement thermique / taille de particule

Evaluation of physicochemical, microbiological and sensorial characteristics of fermented milk beverages with buttermilk addition

“…Buttermilk pH, in general, ranges from 6.4 to 6.8 (Sodini et al. 2006,; Gassi et al. 2008), values near to the ones found in milk and in the present study.…”

“…These differences are probably due to the composition of the cream and the processing parameters to manufacture the butter, such as time and temperature of churning, which can differ from one industry to another. Buttermilk pH, in general, ranges from 6.4 to 6.8 (Sodini et al 2006;Gassi et al 2008), values near to the ones found in milk and in the present study.…”

Effect of cream pasteurization, microfiltration and enzymatic proteolysis on in vitro cholesterol-lowering activity of buttermilk solids

“…Moreover, the impact of different buttermilk processing technologies and enzymatic hydrolysis has not yet been studied. It is known that heat processing of cream modifies the composition and structure of MFGM to a considerable extent [8,24]. Heat treatment denatures whey and MFGM proteins, resulting in the formation of various complexes with caseins [3,5,8,29].…”

Buttermilk ice cream—New method for buttermilk utilization

“…Both cited authors, analogous to our research, obtained buttermilk from sweet cream. According toSodini, Morin, Olabi, and Jiménez-Flores (2006), the use of ether sweet or sour cream for butter production influences the buttermilk composition Gassi et al (2008). pointed out that buttermilk properties depend on origin of milk, heat treatment of cream, and butter technology (slow or rapid churning).…”