blanching is a process similar to pasteurization but with specific application to vegetables and .
following the blanching step, the vegetable is packaged and the temperature is reduced to .
following the blanching step, the vegetable is packaged and the temperature is reduced to .
most of food processing history is based on of the food product, either to control human health concerns or to extend the product shelf life.
the arrhenius equation and similar expressions are very useful in describing the impact of on the rate of change in product quality during processing and storage.
the main cause of food spoilage is
the purpose of processing is to .
unit operations includes .
food preservation methods includes .
the main purpose of food processing is
general speaking, which can inhibit the growth of microbial reproduction or kill microbes, and slow food decaying chemical or biological metaboli, are referred to as a preservative.
all microbial fermentation is for food preservation.
this general objective implies that the processing operation meets the minimum requirement of ensuring any human health safety concerns associated with microbial activity.
what are the concepts related to food processing in this chapter?and how are the principles of these processing concepts to achieve extended foods shelf-life?
pretreatments are designed to enhance , usually through reduction in the initial microbial content.
the d-value will decrease with increasing .
the temperature increase required to cause a one log cycle reduction in the decimal reduction time is defined as .
thermal processes include .
factors influence the heat resistance of microbial included .
food substrates can be ided into .
when a microbial population in a food is exposed to an elevated temperature, microbial population increased with time.
quality attributes of food are no more resistant to thermal processes than the microbial populations.
the slope of the decimal reduction curve increases as the magnitude of the elevated temperature reduces.
explain the meaning of each symbol in f = nd.
blanching is usually used for food, and pasteurization is usually used for food.
factors affect blanching process not includes:
higher quality attributes could obtained under:
in the processing of pasteurized milk, the minimum processing is to destroy
purpose for pasteurization and blanching includes:
continuous htst blanching system includes:
continuous pasteurization system includes:
usually pretreatments can reduction the initial microbial content .
the two key factors in establishing process time for pasteurization are the length of holding tube and the velocity of the fastest moving particle .
what are the stages of the continuous high-temperature short time pasteurization system?
if the ph value of foods is in the range of 3.7 to 4.5, we can call this kind of foods as food.
ph below 3.7, thermal process is based on the thermal resistance of .
thermal processes include , and .
during thermal sterilization of canned foods, the heating rate curve is affected by
influence of sterilization on product quality?
the heating characteristics of food products in containers are ided into three categories: conduction heating,convection heating,mixed or intermediate heating.
according to the regulatory of the food and drug administration, clostridium botulinum must be destroyed on sterilization, and 6d values is required.
explain the reason of obtaining a product in high quality people can use high temperature short time process during pasteurization of milk.
several factors must be controlled for efficient refrigerated storage.these include:
external factors that influence growth of microorfanis in refrigerated foods not include: .
the prumary purpose of refrigerating foods is to extend shelf-life by and .
factors influencing shelf life of refrigerated foods include:
talk about cooling methods for solid foods
in food freezing, there are some factors which damage the food quality, because of .
there many factors would influence the freezing time, including: .
food freezing systems can be ided in to two systems,inclued .
freezing can improve the quality or texture of any food.
a key factor in food freezing is how fast the food is frozen.
why the frozen foods storage temperature should be kept in constant?
the principle of freeze concentration is based on 。
according to the principles of separation, in food industry there are three different techniques used in liquid food concentration ,these techniques are ,respectively.
the principle of membrane separation concentration is based on .
why freeze concentration can be obtained high quality of product?
there are essential components in a spray dryer, they are .
during the convection drying process, the water gradient in the material is opposite to that in the temperature gradient, while in the microwave drying process, the water gradient in the material is the same as the temperature gradient.